Search

Održiva poljoprivreda podrazumeva efikasnu proizvodnju visokokvalitetnih poljoprivrednih proizvoda, sa ciljem da se zaštiti životna sredina, obezbedi zdravlje i dobrobit životinja, održivih društvenih i ekonomskih uslova za farmere, radnike i lokalne zajednice. Sa brzim razvojem globalne ekonomije, nivo potrošnje i potražnje za proizvodima životinjskog porekla kao što su meso, mleko i jaja se po glavi stanovnika značajno povećavaju. Uporedo sa razvojem stočarstva, potrebe za kvalitetnom hranom za životinje se takođe povećavaju. Osnova savremenog koncepta ishrane preživara zasniva se na balansiranoj upotrebi hraniva i kvalitetne nutritivno visoko vredne kabaste hrane u vidu sena, senaže ili silaže. Fermentisana hrana za životinje, silaža, se vrlo često uvodi u ishranu stoke, jer je brojnim studijama i praksom potvrđeno da ovakva hrana ima pozitivan uticaj na kvalitet (sadržaj hranljivih materija, uključujući proteine), ukus i izgled mesa, poboljšava se mramornost mesa i smanjuje se sadržaj vode. Fermentacija je proces u kome se ugljeni hidrati rastvorljivi u vodi (eng. water soluble carbohydrates – WSC) pod anaerobnim uslovima pretvaraju u organske kiseline, uglavnom mlečnu kiselinu, pomoću bakterija mlečne kiseline (lactic acid bacteria – LAB). Raznovrsnost mikrobioma biljnih useva može tok fermentacije da usmeri u negativnom smeru, tačnije da se podstakne rast patogenih mikroorganizama kao što su E. coli, B. cereus, Clostridium botulinum, L. monocytogenes, kvasci i plesni tokom siliranja, što daje nekvalitetnu hranu koja može biti izvor teških bolesti kod ljudi i životinja. Pronalaženje pravog rešenja za siliranje je i dalje veliki izazov, iako na tržištu postoje izvesni preparati koji daju dobre rezultate kada je u pitanju spravljanje silaže. Inokulanti se dodaju u toku procesa siliranja da bi se povećala brojnost pozitivnih bakterija u poređenju sa prirodnom populacijom bakterija koja se nalazi na biljnom materijalu koja prouzrokuje gubitke suve materije usled ne

Održiva poljoprivreda podrazumeva efikasnu proizvodnju visokokvalitetnih poljoprivrednih proizvoda, sa ciljem da se zaštiti životna sredina, obezbedi zdravlje i dobrobit životinja, održivih društvenih i ekonomskih uslova za farmere, radnike i lokalne zajednice. Sa brzim razvojem globalne ekonomije, nivo potrošnje i potražnje za proizvodima životinjskog porekla kao što su meso, mleko i jaja se po glavi stanovnika značajno povećavaju. Uporedo sa razvojem stočarstva, potrebe za kvalitetnom hranom za životinje se takođe povećavaju. Osnova savremenog koncepta ishrane preživara zasniva se na balansiranoj upotrebi hraniva i kvalitetne nutritivno visoko vredne kabaste hrane u vidu sena, senaže ili silaže. Fermentisana hrana za životinje, silaža, se vrlo često uvodi u ishranu stoke, jer je brojnim studijama i praksom potvrđeno da ovakva hrana ima pozitivan uticaj na kvalitet (sadržaj hranljivih materija, uključujući proteine), ukus i izgled mesa, poboljšava se mramornost mesa i smanjuje se sadržaj vode. Fermentacija je proces u kome se ugljeni hidrati rastvorljivi u vodi (eng. water soluble carbohydrates – WSC) pod anaerobnim uslovima pretvaraju u organske kiseline, uglavnom mlečnu kiselinu, pomoću bakterija mlečne kiseline (lactic acid bacteria – LAB). Raznovrsnost mikrobioma biljnih useva može tok fermentacije da usmeri u negativnom smeru, tačnije da se podstakne rast patogenih mikroorganizama kao što su E. coli, B. cereus, Clostridium botulinum, L. monocytogenes, kvasci i plesni tokom siliranja, što daje nekvalitetnu hranu koja može biti izvor teških bolesti kod ljudi i životinja. Pronalaženje pravog rešenja za siliranje je i dalje veliki izazov, iako na tržištu postoje izvesni preparati koji daju dobre rezultate kada je u pitanju spravljanje silaže. Inokulanti se dodaju u toku procesa siliranja da bi se povećala brojnost pozitivnih bakterija u poređenju sa prirodnom populacijom bakterija koja se nalazi na biljnom materijalu koja prouzrokuje gubitke suve materije usled ne

Qymyz is a traditional acidic and ethanolic beverage in central Asian countries made from mare milk fermentation with lactic acid bacteria (LAB) and yeasts. Modeling the growth of microorganisms during fermentation is one of the methods used to control the quality of fermented products. The objective of the study was, firstly, to model the growth kinetics of Kazachstania unispora found in qymyz, and, secondly, to understand their interaction with Lacticaseibacillus casei and Lactobacillus kefiri during the fermentation of mare milk. The K. unispora optimum values of pH and temperature were 4.81 ± 0.22 and 30.16 ± 0.53 °C, respectively, with an optimal growth rate (µopt) of 0.56 ± 0.02 h−1. K. unispora had an ethanol production rate of 6.1 × 10−8 mg·CFU−1. Growth, in terms of limiting substrates showed a lower Ks value for galactose at 0.13 ± 0.04 mg·mL−1 with µopt of 0.45 ± 0.01 h−1, while, for glucose, the Ks was 0.24 ± 0.03 mg·mL−1 with the same µopt. Cocultures of K. unispora were conducted with L. casei and L. kefiri in a synthetic medium and mare milk. The results showed that K. unispora growth was limited and, thus, its ethanol production capacity was inhibited. VOC analysis of mare milk fermented with the studied strains and their cocultures resulted in 37 major volatile compounds. Statistical analysis of the VOC profiles showed that K. unispora modulates the aroma production in coculture with LAB.

Adverse storage conditions impair the quality of stored grain, contribute to the growth and propagation of the fungi leading to an even greater deterioration of the grain quality. Antifungal biopreparations can help preserve grain quality. Lactic acid bacteria (LAB) and their metabolites with antifungal properties can potentially be used in storage conditions or for the decontamination of stored products. The aim of this study was to determine the antifungal activity of Lactobacillus casei, Lactobacillus brevis and Leuconostoc mesenteroides on the inhibition of mycelial growth of pathogenic fungi Aspergillus niger, Penicillium chrysogenum and Fusarium graminearum. The biocontrol potential of LAB against fungi was tested under laboratory conditions in culture media as an ideal substrate for fungal growth and wheat grains as a model of natural substrate. A liquid culture media (MRS broth) was inoculated with cells or cell-free supernatants (CFS) of each LAB species and the fungal spores. The fungal growth was evaluated by measuring the increase in mycelial biomass after 7, 14, 21 and 28 days of incubation. The second antifungal assay was performed on the wheat grain treated with LAB CFS and inoculated with fungal spores. Biopreparation containing cells or CFS of all LAB species significantly inhibited the fungal growth of P. chrysogenum (mean inhibition 69-75% LAB cells and 80-81% LAB CFS) and F. graminearum (mean inhibition 60-83% LAB cells and 83-88% LAB CFS) in the culture media. In the treatment with wheat grain, the CFS of all the tested LAB species significantly inhibited only the growth of F. graminearum (83-90% mean inhibition). There is inconsistency in the efficiency of LAB preparations when comparing assays. The results indicate that media used in the experiment affect the activity or tolerance of the tested bacteria and fungi. L. casei, L. brevis and L. mesenteroides proved their antifungal properties in the culture media and natural substrate. F. graminea

The application of electrical impedance spectroscopy (EIS) is a technique used to monitor, detect and quantify microorganisms of biotechnological interest, with the measurement of electrical parameters of rapid response of a medium inoculated at temperature and constant agitation by submerged electrodes. By making a comparison of the growth model and the plate count with the electrical response parameters, a correlation can be made to break the technological barrier between classical microbiology and rapid detection methods. The comparison of both techniques was performed to determine the maximum growth of Lactobacillus casei (L. casei) ATCC 393. It was found that after inoculation, after 24 h under microaerophilic conditions (37 °C), the maximum microbial growth was recorded by medium of the EIE, using the parameters |Z| (29,1057) and Deg-Deg0 (24,555°). In contrast to the plate count technique, maximum growth was estimated at 9 h. The experimental data obtained through the EIE were adjusted by a series RC circuit; later, the generated curves were adjusted to the growth models of Gompertz and Boltzman. Using the EIE technique, the impedance of the medium was the most efficient parameter for the estimation of the maximum exponential growth peak of L. casei. It was demonstrated that the EIE constitutes an alternative for the rapid detection of the microbial concentration in biomass production processes for the elaboration of probiotic food products., La aplicación de espectroscopia de impedancia eléctrica (EIE), es una técnica que se utiliza para monitorear, detectar y cuantificar microorganismos de interés biotecnológico, con la medición de parámetros eléctricos de respuesta rápida de un medio inoculado a temperatura y agitación constante mediante electrodos sumergidos. Realizando una comparación del modelo de crecimiento y el recuento en placa con los parámetros eléctricos de respuesta, se puede dar una correlación para romper la barrera tecnológica entre la microbiología clásica y los métodos rápidos de detección. La comparación de ambas técnicas fue realizada para determinar el máximo crecimiento de Lactobacillus casei (L. casei) ATCC 393. Se encontró que tras la inoculación, después de 24 h en condiciones microaerofílicas (37 °C), el máximo crecimiento microbiano fue registrado por medio de la EIE, mediante los parámetros |Z| (29,1057) y Deg-Deg0 (24,555°). En contraste con la técnica de conteo en placa, el crecimiento máximo se estimó a las 9 h. Los datos experimentales obtenidos mediante la EIE fueron ajustados por un circuito RC en serie, posteriormente, las curvas generadas fueron ajustadas a los modelos de crecimiento de Gompertz y Boltzman. Usando la técnica de EIE, la impedancia del medio resultó el parámetro más eficiente para la estimación del pico máximo exponencial de crecimiento de L. casei. Se demostró que la EIE constituye una alternativa para la detección rápida de la concentración microbiana en procesos de producción de biomasa para la elaboración de productos alimenticios probióticos.

Objective Pebrine, caused by the microsporidium Nosema bombycis, is one of the severe diseases in Thai polyvoltine strains of the silkworm Bombyx mori. Studies showing the presence of Lactobacillus species in the silkworm gut, where the Nosema parasites enter, suggests that these bacteria may have a protective effect. The aim of this study was to investigate the effect of supplementation of Lactobacillus casei on the survival ratio of silkworm larvae challenged with N. bombycis. Results A group of silkworm larvae of the commercial Thai polyvoltine hybrid strain DokBua was supplemented with L. casei on the second day of the 2nd, 3rd, 4th, and 5th instar. When a control group of silkworm larvae were challenged with N. bombycis on the second day of the 4th instar, the survival rate was 68%, but it was 91% for larvae supplemented with L. casei. For those larvae that survived the treatments until pupation, we determined the growth characters larval weight, cocooning ratio, and pupation ratio, and the economic characters cocoon weight and cocoon shell weight. When infected with N. Bombycis, growth characters were significantly higher in larvae also receiving L. casei.

Objective Pebrine, caused by the microsporidium Nosema bombycis, is one of the severe diseases in Thai polyvoltine strains of the silkworm Bombyx mori. Studies showing the presence of Lactobacillus species in the silkworm gut, where the Nosema parasites enter, suggests that these bacteria may have a protective effect. The aim of this study was to investigate the effect of supplementation of Lactobacillus casei on the survival ratio of silkworm larvae challenged with N. bombycis. Results A group of silkworm larvae of the commercial Thai polyvoltine hybrid strain DokBua was supplemented with L. casei on the second day of the 2nd, 3rd, 4th, and 5th instar. When a control group of silkworm larvae were challenged with N. bombycis on the second day of the 4th instar, the survival rate was 68%, but it was 91% for larvae supplemented with L. casei. For those larvae that survived the treatments until pupation, we determined the growth characters larval weight, cocooning ratio, and pupation ratio, and the economic characters cocoon weight and cocoon shell weight. When infected with N. Bombycis, growth characters were significantly higher in larvae also receiving L. casei.

Objective Pebrine, caused by the microsporidium Nosema bombycis, is one of the severe diseases in Thai polyvoltine strains of the silkworm Bombyx mori. Studies showing the presence of Lactobacillus species in the silkworm gut, where the Nosema parasites enter, suggests that these bacteria may have a protective effect. The aim of this study was to investigate the effect of supplementation of Lactobacillus casei on the survival ratio of silkworm larvae challenged with N. bombycis. Results A group of silkworm larvae of the commercial Thai polyvoltine hybrid strain DokBua was supplemented with L. casei on the second day of the 2nd, 3rd, 4th, and 5th instar. When a control group of silkworm larvae were challenged with N. bombycis on the second day of the 4th instar, the survival rate was 68%, but it was 91% for larvae supplemented with L. casei. For those larvae that survived the treatments until pupation, we determined the growth characters larval weight, cocooning ratio, and pupation ratio, and the economic characters cocoon weight and cocoon shell weight. When infected with N. Bombycis, growth characters were significantly higher in larvae also receiving L. casei.

The application of electrical impedance spectroscopy (EIS) is a technique used to monitor, detect and quantify microorganisms of biotechnological interest, with the measurement of electrical parameters of rapid response of a medium inoculated at temperature and constant agitation by submerged electrodes. By making a comparison of the growth model and the plate count with the electrical response parameters, a correlation can be made to break the technological barrier between classical microbiology and rapid detection methods. The comparison of both techniques was performed to determine the maximum growth of Lactobacillus casei (L. casei) ATCC 393. It was found that after inoculation, after 24 h under microaerophilic conditions (37 °C), the maximum microbial growth was recorded by medium of the EIE, using the parameters |Z| (29,1057) and Deg-Deg0 (24,555°). In contrast to the plate count technique, maximum growth was estimated at 9 h. The experimental data obtained through the EIE were adjusted by a series RC circuit; later, the generated curves were adjusted to the growth models of Gompertz and Boltzman. Using the EIE technique, the impedance of the medium was the most efficient parameter for the estimation of the maximum exponential growth peak of L. casei. It was demonstrated that the EIE constitutes an alternative for the rapid detection of the microbial concentration in biomass production processes for the elaboration of probiotic food products., La aplicación de espectroscopia de impedancia eléctrica (EIE), es una técnica que se utiliza para monitorear, detectar y cuantificar microorganismos de interés biotecnológico, con la medición de parámetros eléctricos de respuesta rápida de un medio inoculado a temperatura y agitación constante mediante electrodos sumergidos. Realizando una comparación del modelo de crecimiento y el recuento en placa con los parámetros eléctricos de respuesta, se puede dar una correlación para romper la barrera tecnológica entre la microbiología clásica y los métodos rápidos de detección. La comparación de ambas técnicas fue realizada para determinar el máximo crecimiento de Lactobacillus casei (L. casei) ATCC 393. Se encontró que tras la inoculación, después de 24 h en condiciones microaerofílicas (37 °C), el máximo crecimiento microbiano fue registrado por medio de la EIE, mediante los parámetros |Z| (29,1057) y Deg-Deg0 (24,555°). En contraste con la técnica de conteo en placa, el crecimiento máximo se estimó a las 9 h. Los datos experimentales obtenidos mediante la EIE fueron ajustados por un circuito RC en serie, posteriormente, las curvas generadas fueron ajustadas a los modelos de crecimiento de Gompertz y Boltzman. Usando la técnica de EIE, la impedancia del medio resultó el parámetro más eficiente para la estimación del pico máximo exponencial de crecimiento de L. casei. Se demostró que la EIE constituye una alternativa para la detección rápida de la concentración microbiana en procesos de producción de biomasa para la elaboración de productos alimenticios probióticos.

Objective Pebrine, caused by the microsporidium Nosema bombycis, is one of the severe diseases in Thai polyvoltine strains of the silkworm Bombyx mori. Studies showing the presence of Lactobacillus species in the silkworm gut, where the Nosema parasites enter, suggests that these bacteria may have a protective effect. The aim of this study was to investigate the effect of supplementation of Lactobacillus casei on the survival ratio of silkworm larvae challenged with N. bombycis. Results A group of silkworm larvae of the commercial Thai polyvoltine hybrid strain DokBua was supplemented with L. casei on the second day of the 2nd, 3rd, 4th, and 5th instar. When a control group of silkworm larvae were challenged with N. bombycis on the second day of the 4th instar, the survival rate was 68%, but it was 91% for larvae supplemented with L. casei. For those larvae that survived the treatments until pupation, we determined the growth characters larval weight, cocooning ratio, and pupation ratio, and the economic characters cocoon weight and cocoon shell weight. When infected with N. Bombycis, growth characters were significantly higher in larvae also receiving L. casei.

The development of new or improved fermented products is significantly stimulated due to the increasing demand for tasty and healthy foods. Libyan soft white cheese is a very popular traditional dairy product in Libya which is made from fresh or pasteurized milk. There is currently no documented research on the manufacture of fresh Libyan white cheese using Lactic acid bacteria. Thus, the present study is to develop a white cheese using the traditional Libyan manufacturing procedure as well as using Lactobacillus spp. Two cultures of lactobacilli (L. acidophilus La-5 and L. casei 431) were evaluated for their proteolytic activity using spectrophotometric assay, and the volatile organic compounds (VOCs) were specified by using headspace solid-phase microextraction coupled to gas chromatography (HS-SPME-GC) on milk fermentation to select the best strain. Both strains were able to exhibit extracellular proteolytic activities in a broad pH range in a liquid medium. L. casei 431 had high extracellular proteolytic activity in an acidic environment (10.50 and 3.31 U/mg in MRS media and whole cow milk, respectively). According to the findings of this study, the analysis of the VOCs produced during the milk fermentation with L. casei 431 and L. acidophilus La-5 led to the identification of a wide range of VOCs. L. casei 431 was able to create more common flavour compounds than L. acidophilus La-5, including 2,3-butanedione, 2-heptanone, 3-hydroxy-2-butanone, and 2-nonanone. The white cheese was made by adding L. casei 431 in the milk and curd. In this study the physico-chemical, microbial, texture parameters, volatile composition and sensory qualities and the effects of cold storage (5 C) on the characteristics of white cheese with the different inoculating stage of starter cultures were evaluated. The white cheese samples made with L. casei 431 kept the microbial quality during storage study. The L. casei 431 resulted in lower springiness, gumminess and chewiness of the wh

The development of new or improved fermented products is significantly stimulated due to the increasing demand for tasty and healthy foods. Libyan soft white cheese is a very popular traditional dairy product in Libya which is made from fresh or pasteurized milk. There is currently no documented research on the manufacture of fresh Libyan white cheese using Lactic acid bacteria. Thus, the present study is to develop a white cheese using the traditional Libyan manufacturing procedure as well as using Lactobacillus spp. Two cultures of lactobacilli (L. acidophilus La-5 and L. casei 431) were evaluated for their proteolytic activity using spectrophotometric assay, and the volatile organic compounds (VOCs) were specified by using headspace solid-phase microextraction coupled to gas chromatography (HS-SPME-GC) on milk fermentation to select the best strain. Both strains were able to exhibit extracellular proteolytic activities in a broad pH range in a liquid medium. L. casei 431 had high extracellular proteolytic activity in an acidic environment (10.50 and 3.31 U/mg in MRS media and whole cow milk, respectively). According to the findings of this study, the analysis of the VOCs produced during the milk fermentation with L. casei 431 and L. acidophilus La-5 led to the identification of a wide range of VOCs. L. casei 431 was able to create more common flavour compounds than L. acidophilus La-5, including 2,3-butanedione, 2-heptanone, 3-hydroxy-2-butanone, and 2-nonanone. The white cheese was made by adding L. casei 431 in the milk and curd. In this study the physico-chemical, microbial, texture parameters, volatile composition and sensory qualities and the effects of cold storage (5 C) on the characteristics of white cheese with the different inoculating stage of starter cultures were evaluated. The white cheese samples made with L. casei 431 kept the microbial quality during storage study. The L. casei 431 resulted in lower springiness, gumminess and chewiness of the wh

The application of electrical impedance spectroscopy (EIS) is a technique used to monitor, detect and quantify microorganisms of biotechnological interest, with the measurement of electrical parameters of rapid response of a medium inoculated at temperature and constant agitation by submerged electrodes. By making a comparison of the growth model and the plate count with the electrical response parameters, a correlation can be made to break the technological barrier between classical microbiology and rapid detection methods. The comparison of both techniques was performed to determine the maximum growth of Lactobacillus casei (L. casei) ATCC 393. It was found that after inoculation, after 24 h under microaerophilic conditions (37 °C), the maximum microbial growth was recorded by medium of the EIE, using the parameters |Z| (29,1057) and Deg-Deg0 (24,555°). In contrast to the plate count technique, maximum growth was estimated at 9 h. The experimental data obtained through the EIE were adjusted by a series RC circuit; later, the generated curves were adjusted to the growth models of Gompertz and Boltzman. Using the EIE technique, the impedance of the medium was the most efficient parameter for the estimation of the maximum exponential growth peak of L. casei. It was demonstrated that the EIE constitutes an alternative for the rapid detection of the microbial concentration in biomass production processes for the elaboration of probiotic food products., La aplicación de espectroscopia de impedancia eléctrica (EIE), es una técnica que se utiliza para monitorear, detectar y cuantificar microorganismos de interés biotecnológico, con la medición de parámetros eléctricos de respuesta rápida de un medio inoculado a temperatura y agitación constante mediante electrodos sumergidos. Realizando una comparación del modelo de crecimiento y el recuento en placa con los parámetros eléctricos de respuesta, se puede dar una correlación para romper la barrera tecnológica entre la microbiología clásica y los métodos rápidos de detección. La comparación de ambas técnicas fue realizada para determinar el máximo crecimiento de Lactobacillus casei (L. casei) ATCC 393. Se encontró que tras la inoculación, después de 24 h en condiciones microaerofílicas (37 °C), el máximo crecimiento microbiano fue registrado por medio de la EIE, mediante los parámetros |Z| (29,1057) y Deg-Deg0 (24,555°). En contraste con la técnica de conteo en placa, el crecimiento máximo se estimó a las 9 h. Los datos experimentales obtenidos mediante la EIE fueron ajustados por un circuito RC en serie, posteriormente, las curvas generadas fueron ajustadas a los modelos de crecimiento de Gompertz y Boltzman. Usando la técnica de EIE, la impedancia del medio resultó el parámetro más eficiente para la estimación del pico máximo exponencial de crecimiento de L. casei. Se demostró que la EIE constituye una alternativa para la detección rápida de la concentración microbiana en procesos de producción de biomasa para la elaboración de productos alimenticios probióticos.

Objective Pebrine, caused by the microsporidium Nosema bombycis, is one of the severe diseases in Thai polyvoltine strains of the silkworm Bombyx mori. Studies showing the presence of Lactobacillus species in the silkworm gut, where the Nosema parasites enter, suggests that these bacteria may have a protective effect. The aim of this study was to investigate the effect of supplementation of Lactobacillus casei on the survival ratio of silkworm larvae challenged with N. bombycis. Results A group of silkworm larvae of the commercial Thai polyvoltine hybrid strain DokBua was supplemented with L. casei on the second day of the 2nd, 3rd, 4th, and 5th instar. When a control group of silkworm larvae were challenged with N. bombycis on the second day of the 4th instar, the survival rate was 68%, but it was 91% for larvae supplemented with L. casei. For those larvae that survived the treatments until pupation, we determined the growth characters larval weight, cocooning ratio, and pupation ratio, and the economic characters cocoon weight and cocoon shell weight. When infected with N. Bombycis, growth characters were significantly higher in larvae also receiving L. casei.

Degradation of undesirable biogenic amines (BAs) in foodstuffs by microorganisms is considered one of the most effective ways of eliminating their toxicity. In this study, we designed two sets of primers for the detection and quantification of the multicopper oxidase gene (MCO), which encodes an enzyme involved in BAs degradation, and endogenous (glyceraldehyde-3-phosphate dehydrogenase) gene (GAPDH) in Lactobacillus casei group by real-time PCR (qPCR). We tested 15 Lactobacillus strains in the screening assays (thus, MCO gene possessing assay (PCR) and monitoring of BAs degradation by HPLC-UV), in which Lactobacillus casei CCDM 198 exhibited the best degradation abilities. For this strain, we monitored the expression of the target gene (MCO) in time (qPCR), the effect of redox treatments (cysteine, ascorbic acid) on the expression of the gene, and the ability to degrade BAs not only in a modified MRS medium (MRS/2) but also in a real food sample (milk). Moreover, decarboxylase activity (ability to form BAs) of this strain was excluded. According to the results, CCDM 198 significantly (P < 0.05) reduced BAs (putrescine, histamine, tyramine, cadaverine), up to 25% decline in 48 h. The highest level of relative expression of MCO (5.21 ± 0.14) was achieved in MRS/2 media with cysteine. © 2020 Elsevier Ltd

The Effect of Ionic Silver Nanoparticles Concentrations on the Inhibition of Lactobacillus casei and pH of MilkABSTRACTTechnological developments support the creation of various nanoparticles that can be utilized, one of which is silver nanoparticles. This study aims to determine the effect of ionic silver nanoparticle concentration on Lactobacillus casei growth inhibition, pH change and curdling of UHT milk. Variation in the concentration of ionic silver nanoparticles of 5, 10, 15, and 20 ppm was tested for their characteristics through UV-VIS spectrophotometry, showing the wave peaks at 413–430 nm, and through the PSA test resulting in the Z-average of 87.2 nm. Ionic silver nanoparticles were tested against L. casei using the Kirby-Bauer diffusion method for 72 hours. The test results showed a change in the clear zone that tended to increase for the concentration of silver nanoparticles 5, 10, 15 and 20 ppm with the gradient values of 0,0032; 0,0280; 0,0395; dan 0,0317, respectively. Tests for pH and UHT milk curdling were carried out for 78 hours and showed that ionic silver nanoparticles tended to be more able to maintain milk pH ±30 hours and curdling ±24 hours longer than milk that was not treated with ionic silver nanoparticles.Keywords: electrolysis; Lactobacillus casei; milk; nanoparticles; silver ABSTRAKPerkembangan teknologi mendukung terciptanya berbagai nanopartikel yang dapat dimanfaatkan, salah satunya nanopartikel perak. Penelitian ini bertujuan untuk mengetahui pengaruh konsentrasi nanopartikel perak ionik terhadap daya hambat Lactobacillus casei, kadar pH, dan penggumpalan pada susu UHT. Variasi konsentrasi nanopartikel perak ionik 5, 10, 15, dan 20 ppm diuji karakteristiknya melalui spektrofotometri UV-VIS dengan hasil puncak gelombang serapan berada pada kisaran 413–430 nm dan uji PSA dengan hasil Z-average berada pada 87,2 nm. Sampel larutan nanopartikel perak ionik diujikan terhadap bakteri L. casei menggunakan metode difusi Kirby-Bauer

The Effect of Ionic Silver Nanoparticles Concentrations on the Inhibition of Lactobacillus casei and pH of MilkABSTRACTTechnological developments support the creation of various nanoparticles that can be utilized, one of which is silver nanoparticles. This study aims to determine the effect of ionic silver nanoparticle concentration on Lactobacillus casei growth inhibition, pH change and curdling of UHT milk. Variation in the concentration of ionic silver nanoparticles of 5, 10, 15, and 20 ppm was tested for their characteristics through UV-VIS spectrophotometry, showing the wave peaks at 413–430 nm, and through the PSA test resulting in the Z-average of 87.2 nm. Ionic silver nanoparticles were tested against L. casei using the Kirby-Bauer diffusion method for 72 hours. The test results showed a change in the clear zone that tended to increase for the concentration of silver nanoparticles 5, 10, 15 and 20 ppm with the gradient values of 0,0032; 0,0280; 0,0395; dan 0,0317, respectively. Tests for pH and UHT milk curdling were carried out for 78 hours and showed that ionic silver nanoparticles tended to be more able to maintain milk pH ±30 hours and curdling ±24 hours longer than milk that was not treated with ionic silver nanoparticles.Keywords: electrolysis; Lactobacillus casei; milk; nanoparticles; silver ABSTRAKPerkembangan teknologi mendukung terciptanya berbagai nanopartikel yang dapat dimanfaatkan, salah satunya nanopartikel perak. Penelitian ini bertujuan untuk mengetahui pengaruh konsentrasi nanopartikel perak ionik terhadap daya hambat Lactobacillus casei, kadar pH, dan penggumpalan pada susu UHT. Variasi konsentrasi nanopartikel perak ionik 5, 10, 15, dan 20 ppm diuji karakteristiknya melalui spektrofotometri UV-VIS dengan hasil puncak gelombang serapan berada pada kisaran 413–430 nm dan uji PSA dengan hasil Z-average berada pada 87,2 nm. Sampel larutan nanopartikel perak ionik diujikan terhadap bakteri L. casei menggunakan metode difusi Kirby-Bauer

The Effect of Ionic Silver Nanoparticles Concentrations on the Inhibition of Lactobacillus casei and pH of MilkABSTRACTTechnological developments support the creation of various nanoparticles that can be utilized, one of which is silver nanoparticles. This study aims to determine the effect of ionic silver nanoparticle concentration on Lactobacillus casei growth inhibition, pH change and curdling of UHT milk. Variation in the concentration of ionic silver nanoparticles of 5, 10, 15, and 20 ppm was tested for their characteristics through UV-VIS spectrophotometry, showing the wave peaks at 413–430 nm, and through the PSA test resulting in the Z-average of 87.2 nm. Ionic silver nanoparticles were tested against L. casei using the Kirby-Bauer diffusion method for 72 hours. The test results showed a change in the clear zone that tended to increase for the concentration of silver nanoparticles 5, 10, 15 and 20 ppm with the gradient values of 0,0032; 0,0280; 0,0395; dan 0,0317, respectively. Tests for pH and UHT milk curdling were carried out for 78 hours and showed that ionic silver nanoparticles tended to be more able to maintain milk pH ±30 hours and curdling ±24 hours longer than milk that was not treated with ionic silver nanoparticles.Keywords: electrolysis; Lactobacillus casei; milk; nanoparticles; silver ABSTRAKPerkembangan teknologi mendukung terciptanya berbagai nanopartikel yang dapat dimanfaatkan, salah satunya nanopartikel perak. Penelitian ini bertujuan untuk mengetahui pengaruh konsentrasi nanopartikel perak ionik terhadap daya hambat Lactobacillus casei, kadar pH, dan penggumpalan pada susu UHT. Variasi konsentrasi nanopartikel perak ionik 5, 10, 15, dan 20 ppm diuji karakteristiknya melalui spektrofotometri UV-VIS dengan hasil puncak gelombang serapan berada pada kisaran 413–430 nm dan uji PSA dengan hasil Z-average berada pada 87,2 nm. Sampel larutan nanopartikel perak ionik diujikan terhadap bakteri L. casei menggunakan metode difusi Kirby-Bauer

The Effect of Ionic Silver Nanoparticles Concentrations on the Inhibition of Lactobacillus casei and pH of MilkABSTRACTTechnological developments support the creation of various nanoparticles that can be utilized, one of which is silver nanoparticles. This study aims to determine the effect of ionic silver nanoparticle concentration on Lactobacillus casei growth inhibition, pH change and curdling of UHT milk. Variation in the concentration of ionic silver nanoparticles of 5, 10, 15, and 20 ppm was tested for their characteristics through UV-VIS spectrophotometry, showing the wave peaks at 413–430 nm, and through the PSA test resulting in the Z-average of 87.2 nm. Ionic silver nanoparticles were tested against L. casei using the Kirby-Bauer diffusion method for 72 hours. The test results showed a change in the clear zone that tended to increase for the concentration of silver nanoparticles 5, 10, 15 and 20 ppm with the gradient values of 0,0032; 0,0280; 0,0395; dan 0,0317, respectively. Tests for pH and UHT milk curdling were carried out for 78 hours and showed that ionic silver nanoparticles tended to be more able to maintain milk pH ±30 hours and curdling ±24 hours longer than milk that was not treated with ionic silver nanoparticles.Keywords: electrolysis; Lactobacillus casei; milk; nanoparticles; silver ABSTRAKPerkembangan teknologi mendukung terciptanya berbagai nanopartikel yang dapat dimanfaatkan, salah satunya nanopartikel perak. Penelitian ini bertujuan untuk mengetahui pengaruh konsentrasi nanopartikel perak ionik terhadap daya hambat Lactobacillus casei, kadar pH, dan penggumpalan pada susu UHT. Variasi konsentrasi nanopartikel perak ionik 5, 10, 15, dan 20 ppm diuji karakteristiknya melalui spektrofotometri UV-VIS dengan hasil puncak gelombang serapan berada pada kisaran 413–430 nm dan uji PSA dengan hasil Z-average berada pada 87,2 nm. Sampel larutan nanopartikel perak ionik diujikan terhadap bakteri L. casei menggunakan metode difusi Kirby-Bauer

A new virulent bacteriophage (MLC-A) was recently isolated in Argentina from a probiotic dairy product containing a strain of Lactobacillus paracasei. Observation of the lysate with an electron microscope revealed bacteriophage particles with an icosahedral capsid of 57 ± 2 nm; with a collar and a noncontractile tail of 156 ± 3 nm terminating with a baseplate to which a tail fiber was attached. Therefore, phage MLC-A belongs to the Siphoviridae family. This phage was able to survive the pasteurization process and was resistant to alcohols and sodium hypochlorite (400 mg/kg). Only peracetic acid could inactivate high-titer suspensions of phages in a short time. The maximum rates of phage adsorption to its host cells were obtained at 30°C with a pH between 5 and 7, and in the presence of calcium or magnesium ions. The host range of phage MLC-A encompassed L. paracasei and Lactobacillus casei strains, but it was not able to infect Lactobacillus rhamnosus or Lactobacillus gasseri strains. One-step growth kinetics of its lytic development revealed latent and burst periods of 30 and 135 min, respectively, with a burst size of about 69 ± 4 plaque-forming units per infected cell. Phage MLC-A had a distinctive restriction profile when compared with the 2 well-studied Lactobacillus phages, PL-1 and J-1. The genome size of the MLC-A phage was estimated to be approximately 37 kb. This study presents the description of the first phage specific for L. paracasei isolated in Argentina. The isolation of phage MLC-A indicates that, beside lactic acid bacteria starters, probiotic cultures can also be sensitive to virulent phages in industrial processes.

Degradation of undesirable biogenic amines (BAs) in foodstuffs by microorganisms is considered one of the most effective ways of eliminating their toxicity. In this study, we designed two sets of primers for the detection and quantification of the multicopper oxidase gene (MCO), which encodes an enzyme involved in BAs degradation, and endogenous (glyceraldehyde-3-phosphate dehydrogenase) gene (GAPDH) in Lactobacillus casei group by real-time PCR (qPCR). We tested 15 Lactobacillus strains in the screening assays (thus, MCO gene possessing assay (PCR) and monitoring of BAs degradation by HPLC-UV), in which Lactobacillus casei CCDM 198 exhibited the best degradation abilities. For this strain, we monitored the expression of the target gene (MCO) in time (qPCR), the effect of redox treatments (cysteine, ascorbic acid) on the expression of the gene, and the ability to degrade BAs not only in a modified MRS medium (MRS/2) but also in a real food sample (milk). Moreover, decarboxylase activity (ability to form BAs) of this strain was excluded. According to the results, CCDM 198 significantly (P < 0.05) reduced BAs (putrescine, histamine, tyramine, cadaverine), up to 25% decline in 48 h. The highest level of relative expression of MCO (5.21 ± 0.14) was achieved in MRS/2 media with cysteine. © 2020 Elsevier Ltd

As a by-product of juice industry, blueberry pomace is still a rich source of phytochemicals with potential benefits for human health. However, studies about blueberry pomace utilization are insufficient. In this study, the blueberry pomace was fermented by the probiotic Lactobacillus casei and the potential function of fermented blueberry pomace (FBP) was evaluated, including the antioxidant activity, the regulation of fecal microbiota and the production of short chain fatty acids (SCFA). The results showed that FBP obtained improved antioxidant activity which was positively correlated with the content of polyphenols. The microbiota community structure was improved by FBP through inhibiting Escherichia coli, Enterococcus and the ratio of Firmicutes and Bacteroidetes as well as improving Bifidobacterium, Ruminococcus, Lactobacillus, Akkermansia and butyrate-producing bacteria. The SCFA, especially acetic, butyric and lactic acids, were remarkably increased because of FBP-supplementation. Further, UPLC-MS analysis showed that forty-six phenolic compounds were detected in FBP while only thirty-eight in non-fermented blueberry pomace (NFBP), explaining the speculation of this study that the phytochemicals in FBP might increase the gut-improving function. This study suggested that the Lactobacillus casei-fermentation was useful for utilizing blueberry pomace as a potential candidate for functional foods.

En esta investigación se buscó obtener Ácido Poliláctico (PLA) utilizando Ácido Láctico de origen biológico fermentado por cepas nativas de Lactobacillus casei y Staphylococcus aureus en un biorreactor PFTR. El biorreactor diseñado tiene un volumen total de 1.236 litros, trabajó a una temperatura de 36 °C. El procedimiento se inició con el aislamiento, caracterización e identificación de dos microrganismos. Las cepas bacterianas fueron Lactobacillus casei y Staphylococcus aureus que se sembraron en sus respectivos medios de cultivos selectivos, que fueron para Lactobacillus casei el medio Rogosa y para Staphyloccocus aureus el medio Manitol Salado. Posteriormente se procedió a determinar la cinética de cada cepa de acuerdo al conteo celular directo mediante el uso de una Cámara de Neubauer dando como resultado, 16.000 Cel/mm3 para la cepa de Lactobacillus casei y 28.000 Cel/mm3 para la cepa de Staphylococcus aureus. Las cepas nativas de Lactobacillus casei y Staphylococcus aureus se adaptaron a un medio especial de producción específico para Ácido Láctico. Una vez reunido estos datos, se procedió al encapsulamiento en perlas de Alginato de sodio con mezcla de CaCl2, que posteriormente fueron llenadas en el Biorreactor PFTR, dicho reactor biológico fue diseñado y construido según las exigencias de las bacterias y de la producción requerida de Ácido Láctico (AL). Para ello se diseñaron modelos en 2D y 3D que simulaban la construcción del reactor biológico tipo Flujo Pistón (PFTR). Luego de producir Ácido Láctico fermentado, posteriormente se realizó un análisis de Espectrofotometría Infrarroja (FT-IR) en donde declara que la cepa de Lactobacillus casei, dio una probabilidad de 80% mientras que la cepa de Staphylococcus aureus, dio una probabilidad de 73% a Ácido Láctico, según la biblioteca espectral de la Universidad Nacional de San Agustín, lo cual permitió concluir que la cepa nativa de Lactobacillus casei aislada presentó mayor performance para generar Ácido Lácti

[ES] La leche humana es un fluido biológico complejo que contiene glicanos bien como oligosacáridos libres (OLH) o bien formando parte de glicoproteínas y glicolípidos. Todos ellos atraviesan el tracto gastrointestinal y llegan intactos al colon, donde son utilizados por bacterias beneficiosas para la salud del bebé. Entre estas bacterias, es de especial relevancia el género Lactobacillus, que se encuentra comúnmente en el tracto gastrointestinal de los lactantes e incluye varias cepas con propiedades probióticas. La N,N’-diacetilquitobiosa (ChbNAc) es un disacárido que forma parte del núcleo de la Nglicosilación de las glicoproteínas presentes en la leche humana y en la mucosa intestinal. Ha sido demostrado con anterioridad que la ChbNAc es utilizada como fuente de carbono por Lactobacillus casei cepa BL23 y que el operón chb está implicado en su metabolismo. Los genes chbRCDE codifican para un hipotético regulador transcripcional, un dominio IIC del sistema de transporte de la fosfotransferasa dependiente de fosfoenolpiruvato (PTS) y dos proteínas hipotéticas D y E, respectivamente, mientras que el cluster de genes chbBAF codifica para los dominios IIB y IIA del PTS, y para una hipotética N-acetiltransferasa. En este trabajo se ha construido un vector para inactivar el gen chbR y se ha obtenido una cepa mutante de L. casei BL23 deficiente en este gen. Se ha observado que este mutante es capaz de utilizar tanto la ChbNAc como el trisacárido N,N’,N’’-diacetilquitotriosa como fuentes de carbono en el medio de cultivo, sugiriendo que el regulador ChbR es un represor transcripcional., [EN] Human milk is a complex biological fluid that contains glycans such as free human milk oligosaccharides (HMO) or forming part of glycoproteins and glycolipids. All of them transit through the gastrointestinal tract and arrive intact to the colon where they are used by beneficial bacteria in order to improve babys’ health. Among these bacteria, especial relevance is according to Lactobacillus genus, which is commonly found at the gastrointestinal tract of infants and includes various strains with probiotic properties. The N,N'-diacetylchitobiose (ChbNAc) is a disaccharide forming part of the N-glycosylation core of the glycoproteins present in human milk and intestinal mucosae. It has been previously shown that the ChbNAc is used as a carbon source by Lactobacillus casei BL23 strain and that the chb operon is involved in its metabolism. The chbRCDE genes encode a hypothetical transcriptional regulator, a IIC domain of the phosphotransferase system (PTS) and two hypothetical proteins, D and E, respectively, whereas the chbBAF gene cluster encodes IIB and IIA PTS domains, and a hypothetical N-acetyltransferase. In this work, a vector has been constructed to inactivate the chbR gene and a mutant strain of L. casei BL23 deficient in this gene has been obtained. It has been observed that this mutant is able to use both ChbNAc and the trisaccharide N,N’,N’’-diacetylchitotriose as carbon sources in the culture medium, suggesting that the chbR regulator is a transcriptional repressor.

Esta investigación tiene como objetivo fundamental evaluar la eficacia del efecto inhibitorio in vitro de un queso artesanal enriquecido con cepas probióticas de Saccharomyces boulardii, Lactobacillus casei y Lactobacillus acidophilus, sobre el crecimiento de Candida albicans. El cual es un hongo causante de la candidiasis oral y otras infecciones que se diseminan por el organismo llegando a ser incluso fatal. El estudio correspondiente fue de corte experimental, prospectivo, transversal, comparativo y de nivel experimental, para el cual se diseñaron tres grupos, uno por cada probiótico, con 10 repeticiones respectivamente. Para la realización de este trabajo se dispuso de cepas certificadas ATCC 10231 de Candida albicans, la cual fue activada e inoculada en los medios de cultivo: Agar Sabouraud, Caldo de tioglicolato, Agar sangre, se procedió a replicar las bacterias en las placas petri posteriormente se colocó los discos de inhibición que contenían los probióticos, mediante el método de Kirby – Bauer o discos de difusión, se incubaron en la cámara de anaerobiosis a 37°C y 6% de CO2 por el lapso de 24 horas. Se realizó las lecturas de los halos de inhibición e interpretación de resultados, utilizando un calibrador de Vernier o una regla milimetrada. Los resultados evidenciaron la efectividad inhibitoria de los probióticos mencionados sobre el crecimiento de Candida albicans, donde el queso artesanal inoculado con Saccharomyces boulardii presentó mayor efectividad inhibitoria. Palabras clave: Probióticos, candidiasis oral, Saccharomyces.boulardii, Lactobacillus casei y Lactobacillus acidophilus

[ES] Los sistemas de transducción de señal de dos componentes (TCS) están típicamente constituidos por una proteína sensor, normalmente anclada en la membrana celular, y un regulador de la respuesta (RR) citoplásmico que generalmente actúa como regulador transcripcional. La detección de un estímulo específico por parte del sensor activa su autofosforilación y subsiguiente transferencia del grupo fosforilo al RR. El estado de fosforilación de este último modula su actividad reguladora, aumentando o reduciendo su afinidad por sus secuencias diana. Aunque una célula puede contener múltiples TCS, la transferencia entre sensores y reguladores asociados suele ser muy específica. Algunos RR pueden también ser fosforilados por metabolitos como el acetil-fosfato, que son indicadores del estado energético celular. PrcR es un RR de Lactobacillus casei que controla la expresión de un gran número de genes en este organismo, especialmente genes implicados en la captación de fuentes de nitrógeno (Alcántara et al. 2016; https://doi.org/10.1111/mmi.13299). En un estudio previo llevado a cabo en el laboratorio de Bacterias Lácticas y Probióticos se ha observado que PrcR puede ser fosforilado independientemente de su sensor asociado PrcK. Con el fin de determinar si PrcR es fosforilado por acetil-fosfato, se plantea la alteración de las rutas de síntesis de acetil-fosfato en este organismo con el objeto de determinar su efecto sobre el estado de fosforilación de PrcR. En Lb. casei los niveles de acetil-P están controlados por las actividades de piruvato oxidasas, fosfotransacetilasa, acetato quinasas y acilfosfatasa. Se dispone de datos transcriptómicos que permiten estimar la expresión de los genes implicados en las condiciones típicas de cultivo de este organismo. El trabajo propuesto planteó en primer lugar, a partir de los datos transcriptómicos, obtener cepas mutantes deficientes de acetato quinasa y fosfotransacetilasa por recombinación homóloga. Con este fin fueron usados vecto, [EN] Two-component signal transduction systems (TCS) are generally constituted by a protein sensor, normally anchored to the cell membrane, and a cytoplasmic response regulator (RR) that generally functions as a transcriptional regulator. The detection of a specific stimulus by the sensor activates its autophosphorylation and subsequent transfer of the phosphoryl group to the RR. The state of phosphorylation of the latter modulates its regulatory activity, increasing or reducing its affinity for its target sequences. Although a cell can have multiple TCS, the transfer between the sensors and the associated regulators are usually very specific. Some of them can also be phosphorylated by metabolites such as acetyl-phosphate, which are indicators of the cellular energy status. PrcR is a RR of Lactobacillus casei that contols the expression of a large number of genes in this organism, especially genes involved in the uptake of nitrogen sources (Alcántara et al., 2016; https://doi.org/10.1111/mmi. 13299). In a previous study carried out in the Laboratory of Lactic Acid Bacteria and Probiotics, it has been observed that PrcR can be phosphorylated independently of its associated sensor PrcK. In order to determine if PrcR is phosphorylated by acetyl-phosphate, it was decided to test the alteration of the routes of synthesis of acetyl-phosphate in this organism in order to determine its effect on the state of the phosphorylation of PrcR. In Lb. casei the levels of acetyl-P are controlled by the activities of pyruvate oxidases, phosphotransacetylase, acetate kinases and acyl phosphatase. Transcriptional data are available to estimate the expression of the genes involved in the typical culture conditions of this organism. The proposed work first raised, from the transcriptomic data, mutant deficient strains of acetate kinase and phosphotransacetylase by homologous recombination. To this end, non-replicative vectors were used following common laboratory methods, the results of

En esta investigación se buscó obtener Ácido Poliláctico (PLA) utilizando Ácido Láctico de origen biológico fermentado por cepas nativas de Lactobacillus casei y Staphylococcus aureus en un biorreactor PFTR. El biorreactor diseñado tiene un volumen total de 1.236 litros, trabajó a una temperatura de 36 °C. El procedimiento se inició con el aislamiento, caracterización e identificación de dos microrganismos. Las cepas bacterianas fueron Lactobacillus casei y Staphylococcus aureus que se sembraron en sus respectivos medios de cultivos selectivos, que fueron para Lactobacillus casei el medio Rogosa y para Staphyloccocus aureus el medio Manitol Salado. Posteriormente se procedió a determinar la cinética de cada cepa de acuerdo al conteo celular directo mediante el uso de una Cámara de Neubauer dando como resultado, 16.000 Cel/mm3 para la cepa de Lactobacillus casei y 28.000 Cel/mm3 para la cepa de Staphylococcus aureus. Las cepas nativas de Lactobacillus casei y Staphylococcus aureus se adaptaron a un medio especial de producción específico para Ácido Láctico. Una vez reunido estos datos, se procedió al encapsulamiento en perlas de Alginato de sodio con mezcla de CaCl2, que posteriormente fueron llenadas en el Biorreactor PFTR, dicho reactor biológico fue diseñado y construido según las exigencias de las bacterias y de la producción requerida de Ácido Láctico (AL). Para ello se diseñaron modelos en 2D y 3D que simulaban la construcción del reactor biológico tipo Flujo Pistón (PFTR). Luego de producir Ácido Láctico fermentado, posteriormente se realizó un análisis de Espectrofotometría Infrarroja (FT-IR) en donde declara que la cepa de Lactobacillus casei, dio una probabilidad de 80% mientras que la cepa de Staphylococcus aureus, dio una probabilidad de 73% a Ácido Láctico, según la biblioteca espectral de la Universidad Nacional de San Agustín, lo cual permitió concluir que la cepa nativa de Lactobacillus casei aislada presentó mayor performance para generar Ácido Lácti

[ES] La leche humana es un fluido biológico complejo que contiene glicanos bien como oligosacáridos libres (OLH) o bien formando parte de glicoproteínas y glicolípidos. Todos ellos atraviesan el tracto gastrointestinal y llegan intactos al colon, donde son utilizados por bacterias beneficiosas para la salud del bebé. Entre estas bacterias, es de especial relevancia el género Lactobacillus, que se encuentra comúnmente en el tracto gastrointestinal de los lactantes e incluye varias cepas con propiedades probióticas. La N,N’-diacetilquitobiosa (ChbNAc) es un disacárido que forma parte del núcleo de la Nglicosilación de las glicoproteínas presentes en la leche humana y en la mucosa intestinal. Ha sido demostrado con anterioridad que la ChbNAc es utilizada como fuente de carbono por Lactobacillus casei cepa BL23 y que el operón chb está implicado en su metabolismo. Los genes chbRCDE codifican para un hipotético regulador transcripcional, un dominio IIC del sistema de transporte de la fosfotransferasa dependiente de fosfoenolpiruvato (PTS) y dos proteínas hipotéticas D y E, respectivamente, mientras que el cluster de genes chbBAF codifica para los dominios IIB y IIA del PTS, y para una hipotética N-acetiltransferasa. En este trabajo se ha construido un vector para inactivar el gen chbR y se ha obtenido una cepa mutante de L. casei BL23 deficiente en este gen. Se ha observado que este mutante es capaz de utilizar tanto la ChbNAc como el trisacárido N,N’,N’’-diacetilquitotriosa como fuentes de carbono en el medio de cultivo, sugiriendo que el regulador ChbR es un represor transcripcional., [EN] Human milk is a complex biological fluid that contains glycans such as free human milk oligosaccharides (HMO) or forming part of glycoproteins and glycolipids. All of them transit through the gastrointestinal tract and arrive intact to the colon where they are used by beneficial bacteria in order to improve babys’ health. Among these bacteria, especial relevance is according to Lactobacillus genus, which is commonly found at the gastrointestinal tract of infants and includes various strains with probiotic properties. The N,N'-diacetylchitobiose (ChbNAc) is a disaccharide forming part of the N-glycosylation core of the glycoproteins present in human milk and intestinal mucosae. It has been previously shown that the ChbNAc is used as a carbon source by Lactobacillus casei BL23 strain and that the chb operon is involved in its metabolism. The chbRCDE genes encode a hypothetical transcriptional regulator, a IIC domain of the phosphotransferase system (PTS) and two hypothetical proteins, D and E, respectively, whereas the chbBAF gene cluster encodes IIB and IIA PTS domains, and a hypothetical N-acetyltransferase. In this work, a vector has been constructed to inactivate the chbR gene and a mutant strain of L. casei BL23 deficient in this gene has been obtained. It has been observed that this mutant is able to use both ChbNAc and the trisaccharide N,N’,N’’-diacetylchitotriose as carbon sources in the culture medium, suggesting that the chbR regulator is a transcriptional repressor.

[ES] La leche humana es un fluido biológico complejo que contiene glicanos bien como oligosacáridos libres (OLH) o bien formando parte de glicoproteínas y glicolípidos. Todos ellos atraviesan el tracto gastrointestinal y llegan intactos al colon, donde son utilizados por bacterias beneficiosas para la salud del bebé. Entre estas bacterias, es de especial relevancia el género Lactobacillus, que se encuentra comúnmente en el tracto gastrointestinal de los lactantes e incluye varias cepas con propiedades probióticas. La N,N’-diacetilquitobiosa (ChbNAc) es un disacárido que forma parte del núcleo de la Nglicosilación de las glicoproteínas presentes en la leche humana y en la mucosa intestinal. Ha sido demostrado con anterioridad que la ChbNAc es utilizada como fuente de carbono por Lactobacillus casei cepa BL23 y que el operón chb está implicado en su metabolismo. Los genes chbRCDE codifican para un hipotético regulador transcripcional, un dominio IIC del sistema de transporte de la fosfotransferasa dependiente de fosfoenolpiruvato (PTS) y dos proteínas hipotéticas D y E, respectivamente, mientras que el cluster de genes chbBAF codifica para los dominios IIB y IIA del PTS, y para una hipotética N-acetiltransferasa. En este trabajo se ha construido un vector para inactivar el gen chbR y se ha obtenido una cepa mutante de L. casei BL23 deficiente en este gen. Se ha observado que este mutante es capaz de utilizar tanto la ChbNAc como el trisacárido N,N’,N’’-diacetilquitotriosa como fuentes de carbono en el medio de cultivo, sugiriendo que el regulador ChbR es un represor transcripcional., [EN] Human milk is a complex biological fluid that contains glycans such as free human milk oligosaccharides (HMO) or forming part of glycoproteins and glycolipids. All of them transit through the gastrointestinal tract and arrive intact to the colon where they are used by beneficial bacteria in order to improve babys’ health. Among these bacteria, especial relevance is according to Lactobacillus genus, which is commonly found at the gastrointestinal tract of infants and includes various strains with probiotic properties. The N,N'-diacetylchitobiose (ChbNAc) is a disaccharide forming part of the N-glycosylation core of the glycoproteins present in human milk and intestinal mucosae. It has been previously shown that the ChbNAc is used as a carbon source by Lactobacillus casei BL23 strain and that the chb operon is involved in its metabolism. The chbRCDE genes encode a hypothetical transcriptional regulator, a IIC domain of the phosphotransferase system (PTS) and two hypothetical proteins, D and E, respectively, whereas the chbBAF gene cluster encodes IIB and IIA PTS domains, and a hypothetical N-acetyltransferase. In this work, a vector has been constructed to inactivate the chbR gene and a mutant strain of L. casei BL23 deficient in this gene has been obtained. It has been observed that this mutant is able to use both ChbNAc and the trisaccharide N,N’,N’’-diacetylchitotriose as carbon sources in the culture medium, suggesting that the chbR regulator is a transcriptional repressor.

Esta investigación tiene como objetivo fundamental evaluar la eficacia del efecto inhibitorio in vitro de un queso artesanal enriquecido con cepas probióticas de Saccharomyces boulardii, Lactobacillus casei y Lactobacillus acidophilus, sobre el crecimiento de Candida albicans. El cual es un hongo causante de la candidiasis oral y otras infecciones que se diseminan por el organismo llegando a ser incluso fatal. El estudio correspondiente fue de corte experimental, prospectivo, transversal, comparativo y de nivel experimental, para el cual se diseñaron tres grupos, uno por cada probiótico, con 10 repeticiones respectivamente. Para la realización de este trabajo se dispuso de cepas certificadas ATCC 10231 de Candida albicans, la cual fue activada e inoculada en los medios de cultivo: Agar Sabouraud, Caldo de tioglicolato, Agar sangre, se procedió a replicar las bacterias en las placas petri posteriormente se colocó los discos de inhibición que contenían los probióticos, mediante el método de Kirby – Bauer o discos de difusión, se incubaron en la cámara de anaerobiosis a 37°C y 6% de CO2 por el lapso de 24 horas. Se realizó las lecturas de los halos de inhibición e interpretación de resultados, utilizando un calibrador de Vernier o una regla milimetrada. Los resultados evidenciaron la efectividad inhibitoria de los probióticos mencionados sobre el crecimiento de Candida albicans, donde el queso artesanal inoculado con Saccharomyces boulardii presentó mayor efectividad inhibitoria. Palabras clave: Probióticos, candidiasis oral, Saccharomyces.boulardii, Lactobacillus casei y Lactobacillus acidophilus

[ES] Los sistemas de transducción de señal de dos componentes (TCS) están típicamente constituidos por una proteína sensor, normalmente anclada en la membrana celular, y un regulador de la respuesta (RR) citoplásmico que generalmente actúa como regulador transcripcional. La detección de un estímulo específico por parte del sensor activa su autofosforilación y subsiguiente transferencia del grupo fosforilo al RR. El estado de fosforilación de este último modula su actividad reguladora, aumentando o reduciendo su afinidad por sus secuencias diana. Aunque una célula puede contener múltiples TCS, la transferencia entre sensores y reguladores asociados suele ser muy específica. Algunos RR pueden también ser fosforilados por metabolitos como el acetil-fosfato, que son indicadores del estado energético celular. PrcR es un RR de Lactobacillus casei que controla la expresión de un gran número de genes en este organismo, especialmente genes implicados en la captación de fuentes de nitrógeno (Alcántara et al. 2016; https://doi.org/10.1111/mmi.13299). En un estudio previo llevado a cabo en el laboratorio de Bacterias Lácticas y Probióticos se ha observado que PrcR puede ser fosforilado independientemente de su sensor asociado PrcK. Con el fin de determinar si PrcR es fosforilado por acetil-fosfato, se plantea la alteración de las rutas de síntesis de acetil-fosfato en este organismo con el objeto de determinar su efecto sobre el estado de fosforilación de PrcR. En Lb. casei los niveles de acetil-P están controlados por las actividades de piruvato oxidasas, fosfotransacetilasa, acetato quinasas y acilfosfatasa. Se dispone de datos transcriptómicos que permiten estimar la expresión de los genes implicados en las condiciones típicas de cultivo de este organismo. El trabajo propuesto planteó en primer lugar, a partir de los datos transcriptómicos, obtener cepas mutantes deficientes de acetato quinasa y fosfotransacetilasa por recombinación homóloga. Con este fin fueron usados vecto, [EN] Two-component signal transduction systems (TCS) are generally constituted by a protein sensor, normally anchored to the cell membrane, and a cytoplasmic response regulator (RR) that generally functions as a transcriptional regulator. The detection of a specific stimulus by the sensor activates its autophosphorylation and subsequent transfer of the phosphoryl group to the RR. The state of phosphorylation of the latter modulates its regulatory activity, increasing or reducing its affinity for its target sequences. Although a cell can have multiple TCS, the transfer between the sensors and the associated regulators are usually very specific. Some of them can also be phosphorylated by metabolites such as acetyl-phosphate, which are indicators of the cellular energy status. PrcR is a RR of Lactobacillus casei that contols the expression of a large number of genes in this organism, especially genes involved in the uptake of nitrogen sources (Alcántara et al., 2016; https://doi.org/10.1111/mmi. 13299). In a previous study carried out in the Laboratory of Lactic Acid Bacteria and Probiotics, it has been observed that PrcR can be phosphorylated independently of its associated sensor PrcK. In order to determine if PrcR is phosphorylated by acetyl-phosphate, it was decided to test the alteration of the routes of synthesis of acetyl-phosphate in this organism in order to determine its effect on the state of the phosphorylation of PrcR. In Lb. casei the levels of acetyl-P are controlled by the activities of pyruvate oxidases, phosphotransacetylase, acetate kinases and acyl phosphatase. Transcriptional data are available to estimate the expression of the genes involved in the typical culture conditions of this organism. The proposed work first raised, from the transcriptomic data, mutant deficient strains of acetate kinase and phosphotransacetylase by homologous recombination. To this end, non-replicative vectors were used following common laboratory methods, the results of

En esta investigación se buscó obtener Ácido Poliláctico (PLA) utilizando Ácido Láctico de origen biológico fermentado por cepas nativas de Lactobacillus casei y Staphylococcus aureus en un biorreactor PFTR. El biorreactor diseñado tiene un volumen total de 1.236 litros, trabajó a una temperatura de 36 °C. El procedimiento se inició con el aislamiento, caracterización e identificación de dos microrganismos. Las cepas bacterianas fueron Lactobacillus casei y Staphylococcus aureus que se sembraron en sus respectivos medios de cultivos selectivos, que fueron para Lactobacillus casei el medio Rogosa y para Staphyloccocus aureus el medio Manitol Salado. Posteriormente se procedió a determinar la cinética de cada cepa de acuerdo al conteo celular directo mediante el uso de una Cámara de Neubauer dando como resultado, 16.000 Cel/mm3 para la cepa de Lactobacillus casei y 28.000 Cel/mm3 para la cepa de Staphylococcus aureus. Las cepas nativas de Lactobacillus casei y Staphylococcus aureus se adaptaron a un medio especial de producción específico para Ácido Láctico. Una vez reunido estos datos, se procedió al encapsulamiento en perlas de Alginato de sodio con mezcla de CaCl2, que posteriormente fueron llenadas en el Biorreactor PFTR, dicho reactor biológico fue diseñado y construido según las exigencias de las bacterias y de la producción requerida de Ácido Láctico (AL). Para ello se diseñaron modelos en 2D y 3D que simulaban la construcción del reactor biológico tipo Flujo Pistón (PFTR). Luego de producir Ácido Láctico fermentado, posteriormente se realizó un análisis de Espectrofotometría Infrarroja (FT-IR) en donde declara que la cepa de Lactobacillus casei, dio una probabilidad de 80% mientras que la cepa de Staphylococcus aureus, dio una probabilidad de 73% a Ácido Láctico, según la biblioteca espectral de la Universidad Nacional de San Agustín, lo cual permitió concluir que la cepa nativa de Lactobacillus casei aislada presentó mayor performance para generar Ácido Lácti

Lactobacillus casei and Lactobacillus rhamnosus proteins P40 and P75 belong to a large family of secreted cell wall proteins that contain a carboxy(C)-terminal CHAP or NlpC/P60 superfamily domains. In addition to their peptidoglycan hydrolases activity, proteins in this family are specific antigens of pathogens, frequently responsible of interactions with the host. L. rhamnosus GG and L. casei BL23 purified P40 and P75 proteins have antiapoptotic activity by inducing the EGF/Akt pathway. The aim of this work was to study the genetics, phylogeny and dissemination of this family of proteins in the genus Lactobacillus as well as their characteristics and likely function. The scrutiny of their DNA encoding sequences revealed the presence of minisatellite DNA in the P75 encoding gene of L. casei/paracasei strains (cmuB) with intraspecific indels that gave raise to four different alleles (cmuB1–4), which are exclusive of this species. Phylogenic analyses suggest that both proteins are present mainly in the L. casei and Lactobacillus sakei phylogenomic groups. A P40 ancestral gene was possibly present in the common ancestor of Enterococcaceae, Lactobacillaceae and Streptococcaceae. P75 is also present in L. casei and L. sakei groups, but its evolution is difficult to explain only by vertical transmission. Antibodies raised against the N-terminal regions of P40 and P75 improved their immunological detection in culture supernatants as they recognized almost exclusively proteins of L. casei/paracasei/rhamnosus strains, highlighting their structural similarity, that allowed to detect them in different fermented dairy products that contained probiotic L. casei strains. Purified P40 and P75 proteins showed no evident lytic activity but they complemented L. casei BL23 cmuA and cmuB defective mutants, respectively, thus proving that they actively participate in cell division.

This work was carried out in the FCP food processing laboratory of ESPOCH. Guanabana pulp with different probiotic levels (Lactobacillus casei) was processed using 16 pulp samples that were distributed in 4 treatments and 4 replicates, modeled with a completely random design, where physical – chemical, organoleptic and microbiological characteristics were evaluated; As well as the shelf life and economic parameter, the guanabana pulp was stored at -20°C. The results obtained show that there is no statistically significant difference between treatments for mesophilic and mold/yeast, Guanabana pulp presented significant changes in lactic acid bacteria (BAL) among treatments, the highest concentration was obtained from treatment 1.5%probiotics (106 CFU/ml); No total coliforms were present in any of the treatments. The organoleptic characteristics of the guanabana pulp in all treatments registered an acceptability of good and very good without significant differences. When working with the treatment 1.5% of Lactobacillus casei a longer life is obtained. The highest profitability is achieved by working with 0% probiotic but without functional benefit, this product should be marketed at a higher price than it has functional properties., Este trabajo se realizó en el laboratorio de procesamiento de alimentos de la FCP, de la ESPOCH, se procesó pulpa de guanábana con diferentes niveles de probiótico (Lactobacillus casei), utilizando 16 muestras de pulpa que fueron distribuidas en 4 tratamientos y 4 repeticiones, modeladas con un diseño completamente al azar, donde se evaluó las características físico-química, organolépticas, microbiológicas; así como la vida útil y el parámetro económico, se almacenó la pulpa de guanábana a -20°C. Los resultados obtenidos mostraron que no hay diferencia estadística significativa entre los tratamientos en el parámetro de °Brix, mientras que presentó disminuciones estadísticas significativas en los parámetros de pH y acidez. Los resultados microbiológicos obtenidos mostraron que no hay diferencia estadística significativa entre los tratamientos para aerobios mesófilos y mohos/levaduras, la pulpa de guanábana presentó cambios significativos en bacterias ácido lácticos (BAL) entre los tratamientos, la máxima concentración se obtuvo a partir del tratamiento 1,5% de probióticos (106 UFC/ml); no hubo presencia de coliformes totales en ninguno de los tratamientos. Las características organolépticas de la pulpa de guanábana en todos los tratamientos registraron una aceptabilidad de buena y muy buena sin diferencias significativas. Al trabajar con el tratamiento 1,5% de Lactobacillus casei se obtiene una mayor vida útil. La mayor rentabilidad se consigue al trabajar con el 0% de probiótico pero sin beneficio funcional, mientras que al trabajar con el tratamiento 1,5% de probióticos se obtiene un beneficio-costo negativo, este producto deberá comercializarse a un mayor precio debido a que posee propiedades funcionales.

[EN] This work presents the development of a probiotic dried apple snack consisting of dried apple cubes impregnated with Lactobacillus casei NRRL B-442. Apple cubes were impregnated with probiotic microorganisms and dried under different temperatures (10-60 degrees C), with or without application of ultrasound. The viability of Lactobacillus casei in the dried apple snack was evaluated studying the effects of drying conditions and ultrasound application (as a drying enhancing technology). A mathematical model was developed to predict the drying kinetics and the inactivation of Lactobacillus casei. Drying and microorganism inactivation rates increased with increasing process temperature and with ultrasound application. The concentration of probiotics in the apple snacks was similar to the concentration of microorganisms in commercial probiotic dairy products when the apples were dried at 60 degrees C or when ultrasound-assisted air-drying was applied, thus proving that the production of dried probiotic apple snacks is possible and technically viable.

[EN] This work presents the development of a probiotic dried apple snack consisting of dried apple cubes impregnated with Lactobacillus casei NRRL B-442. Apple cubes were impregnated with probiotic microorganisms and dried under different temperatures (10-60 degrees C), with or without application of ultrasound. The viability of Lactobacillus casei in the dried apple snack was evaluated studying the effects of drying conditions and ultrasound application (as a drying enhancing technology). A mathematical model was developed to predict the drying kinetics and the inactivation of Lactobacillus casei. Drying and microorganism inactivation rates increased with increasing process temperature and with ultrasound application. The concentration of probiotics in the apple snacks was similar to the concentration of microorganisms in commercial probiotic dairy products when the apples were dried at 60 degrees C or when ultrasound-assisted air-drying was applied, thus proving that the production of dried probiotic apple snacks is possible and technically viable.

Fermented milk is a common beverage in many countries, but its flavor is highly variable from one region to another. The fermented mare milk, common beverage in Central Asia, has a typical flavor of koumiss, but those flavors were never described using aroma compound determination. In the present study, six lactic acid bacteria were identified in local koumiss. Due to the apparent technological advantage of Lactobacillus casei and Streptococcus thermophilus (notably their acidification speed), the main objective of this study was to compare their volatile compound profiles. 35 aromatic compounds were detected. To compare the aroma profiles of each strain, the ratio proportion strain/control was calculated for each strain and for each aroma showing significantly different profiles with predominance of 2-methyl-1-propanol and 2-undecanol in milk fermented with L. casei, and of 2,3-pentanedione in milk fermented with S. thermophilus. L. casei strain produced more aroma and its profile was significantly (P>0.03) different from S. thermophilus profile.

The interest about probiotic bacteria supplementation in fruit beverages has been increased recently in order to develop functional beverages without lactose. That is a technological challenge since pH and storage temperature can affect their viability. The aim of this study was to evaluate the viability of three commercial probiotic strains (L. paracasei, L. casei and L. rhamnosus) in mango beverage stored at 4°C. This research was developed in three stages: the assessment of the acid strain tolerance, the selection of a prebiotic as cellular protectant against environmental stress, the evaluation of physiochemical and sensory stability during storage. L. casei was chosen as the most stable strain with FOS at 5% as a prebiotic substance that stimulated its growth. At the final stage, it was found that L. casei produced significant changes in pH and titratable acidity in mango beverages after one week at 4°C, which was also detected by consumers with good sensory acceptance, La inclusión de bacterias probióticas en bebidas de frutas representa un gran reto tecnológico, debido a que la viabilidad de los microrganismos es afectada por varios factores, entre ellos el pH y la temperatura de almacenamiento. El objetivo de este trabajo fue evaluar la viabilidad de tres cepas probióticas comerciales (L. paracasei, L. casei and L. rhamnosus) en bebida de mango almacenada a 4°C. Esta investigación se desarrolló en tres etapas: evaluación ácido tolerancia de las cepas probióticas, selección sustancia prebiótica como protector celular y la estabilidad sensorial y físicoquímica de la bebida durante el almacenamiento. Se determinó que L. casei fue la cepa más estable en bebida de mango y FOS al 5% la sustancia que estimuló en mayor cantidad su crecimiento. Además, la inclusión de L. casei generó cambios significativos en el pH y la acidez titulable transcurrida una semana de almacenamiento a 4°C, los cuales fueron detectados por los consumidores

The interest about probiotic bacteria supplementation in fruit beverages has been increased recently in order to develop functional beverages without lactose. That is a technological challenge since pH and storage temperature can affect their viability. The aim of this study was to evaluate the viability of three commercial probiotic strains (L. paracasei, L. casei and L. rhamnosus) in mango beverage stored at 4°C. This research was developed in three stages: the assessment of the acid strain tolerance, the selection of a prebiotic as cellular protectant against environmental stress, the evaluation of physiochemical and sensory stability during storage. L. casei was chosen as the most stable strain with FOS at 5% as a prebiotic substance that stimulated its growth. At the final stage, it was found that L. casei produced significant changes in pH and titratable acidity in mango beverages after one week at 4°C, which was also detected by consumers with good sensory acceptance, La inclusión de bacterias probióticas en bebidas de frutas representa un gran reto tecnológico, debido a que la viabilidad de los microrganismos es afectada por varios factores, entre ellos el pH y la temperatura de almacenamiento. El objetivo de este trabajo fue evaluar la viabilidad de tres cepas probióticas comerciales (L. paracasei, L. casei and L. rhamnosus) en bebida de mango almacenada a 4°C. Esta investigación se desarrolló en tres etapas: evaluación ácido tolerancia de las cepas probióticas, selección sustancia prebiótica como protector celular y la estabilidad sensorial y físicoquímica de la bebida durante el almacenamiento. Se determinó que L. casei fue la cepa más estable en bebida de mango y FOS al 5% la sustancia que estimuló en mayor cantidad su crecimiento. Además, la inclusión de L. casei generó cambios significativos en el pH y la acidez titulable transcurrida una semana de almacenamiento a 4°C, los cuales fueron detectados por los consumidores

The Effect of Broiler Manure with Lactobacillus casei Fermentation on the Kampung Chicken Feed Convertion Ratio ABSTRACTHusbandry of kampung chicken is constrained by high feed prices and poor productivity. This study aims to utilize alternative feed materials derived from broiler manure to obtain a cheaper feed with good quality. Manure contains high nutrients. Manure was fermented using Lactobacillus casei to improve feed conversion. Two hundred chickens were divided into 4 groups (n = 50). Groups P1, P2, and P3 were given 4%, 8%, and 12% fermentation of L. casei, respectively. Group P0 was given a regular feed without L. casei. Each treatment group consisted of four replicates and were maintained for 60 days. The research design used was Completely Randomized Design subjected to analysis of variant (ANOVA) followed by Duncan test. The feed conversion values of groups P0, P1, P2, and P3 were 4.46; 4.38; 4.21; and 4.54, respectively. The results showed that the feed conversion was not significant in all groups. It was concluded that L. casei fermenter could not improve the feed conversion ratio (FCR).Keywords: FCR, fermentation, kampung chicken, Lactobacillus casei, manure ABSTRAKBudidaya ayam kampung terkendala tingginya harga pakan dan rendahnya produktivitas. Penelitian ini bertujuan memanfaatkan pakan alternatif bersumber manur (limbah kotoran) ayam broiler untuk memperoleh pakan murah dengan kualitas baik. Manur broiler masih mengandung nutrisi yang tinggi. Manur difermentasi menggunakan Lactobacillus casei untuk memperbaiki konversi pakan. Dua ratus ekor ayam dibagi menjadi 4 kelompok (n=50 ekor). Kelompok P1, P2, dan P3 masing-masing diberi ransum yang ditambah fermentasi L. casei sebanyak 4%, 8%, dan 12%. Kelompok P0 diberikan pakan biasa tanpa penambahan L. casei. Setiap kelompok perlakuan terdiri dari empat ulangan dipelihara selama 60 hari. Penelitian menggunakan Rancangan Acak Lengkap (RAL) dengan analisis ragam yang dilanjutkan dengan uji Duncan. Kon

The Effect of Broiler Manure with Lactobacillus casei Fermentation on the Kampung Chicken Feed Convertion Ratio ABSTRACTHusbandry of kampung chicken is constrained by high feed prices and poor productivity. This study aims to utilize alternative feed materials derived from broiler manure to obtain a cheaper feed with good quality. Manure contains high nutrients. Manure was fermented using Lactobacillus casei to improve feed conversion. Two hundred chickens were divided into 4 groups (n = 50). Groups P1, P2, and P3 were given 4%, 8%, and 12% fermentation of L. casei, respectively. Group P0 was given a regular feed without L. casei. Each treatment group consisted of four replicates and were maintained for 60 days. The research design used was Completely Randomized Design subjected to analysis of variant (ANOVA) followed by Duncan test. The feed conversion values of groups P0, P1, P2, and P3 were 4.46; 4.38; 4.21; and 4.54, respectively. The results showed that the feed conversion was not significant in all groups. It was concluded that L. casei fermenter could not improve the feed conversion ratio (FCR).Keywords: FCR, fermentation, kampung chicken, Lactobacillus casei, manure ABSTRAKBudidaya ayam kampung terkendala tingginya harga pakan dan rendahnya produktivitas. Penelitian ini bertujuan memanfaatkan pakan alternatif bersumber manur (limbah kotoran) ayam broiler untuk memperoleh pakan murah dengan kualitas baik. Manur broiler masih mengandung nutrisi yang tinggi. Manur difermentasi menggunakan Lactobacillus casei untuk memperbaiki konversi pakan. Dua ratus ekor ayam dibagi menjadi 4 kelompok (n=50 ekor). Kelompok P1, P2, dan P3 masing-masing diberi ransum yang ditambah fermentasi L. casei sebanyak 4%, 8%, dan 12%. Kelompok P0 diberikan pakan biasa tanpa penambahan L. casei. Setiap kelompok perlakuan terdiri dari empat ulangan dipelihara selama 60 hari. Penelitian menggunakan Rancangan Acak Lengkap (RAL) dengan analisis ragam yang dilanjutkan dengan uji Duncan. Kon

The Effect of Broiler Manure with Lactobacillus casei Fermentation on the Kampung Chicken Feed Convertion Ratio ABSTRACTHusbandry of kampung chicken is constrained by high feed prices and poor productivity. This study aims to utilize alternative feed materials derived from broiler manure to obtain a cheaper feed with good quality. Manure contains high nutrients. Manure was fermented using Lactobacillus casei to improve feed conversion. Two hundred chickens were divided into 4 groups (n = 50). Groups P1, P2, and P3 were given 4%, 8%, and 12% fermentation of L. casei, respectively. Group P0 was given a regular feed without L. casei. Each treatment group consisted of four replicates and were maintained for 60 days. The research design used was Completely Randomized Design subjected to analysis of variant (ANOVA) followed by Duncan test. The feed conversion values of groups P0, P1, P2, and P3 were 4.46; 4.38; 4.21; and 4.54, respectively. The results showed that the feed conversion was not significant in all groups. It was concluded that L. casei fermenter could not improve the feed conversion ratio (FCR).Keywords: FCR, fermentation, kampung chicken, Lactobacillus casei, manure ABSTRAKBudidaya ayam kampung terkendala tingginya harga pakan dan rendahnya produktivitas. Penelitian ini bertujuan memanfaatkan pakan alternatif bersumber manur (limbah kotoran) ayam broiler untuk memperoleh pakan murah dengan kualitas baik. Manur broiler masih mengandung nutrisi yang tinggi. Manur difermentasi menggunakan Lactobacillus casei untuk memperbaiki konversi pakan. Dua ratus ekor ayam dibagi menjadi 4 kelompok (n=50 ekor). Kelompok P1, P2, dan P3 masing-masing diberi ransum yang ditambah fermentasi L. casei sebanyak 4%, 8%, dan 12%. Kelompok P0 diberikan pakan biasa tanpa penambahan L. casei. Setiap kelompok perlakuan terdiri dari empat ulangan dipelihara selama 60 hari. Penelitian menggunakan Rancangan Acak Lengkap (RAL) dengan analisis ragam yang dilanjutkan dengan uji Duncan. Kon

The Effect of Broiler Manure with Lactobacillus casei Fermentation on the Kampung Chicken Feed Convertion Ratio ABSTRACTHusbandry of kampung chicken is constrained by high feed prices and poor productivity. This study aims to utilize alternative feed materials derived from broiler manure to obtain a cheaper feed with good quality. Manure contains high nutrients. Manure was fermented using Lactobacillus casei to improve feed conversion. Two hundred chickens were divided into 4 groups (n = 50). Groups P1, P2, and P3 were given 4%, 8%, and 12% fermentation of L. casei, respectively. Group P0 was given a regular feed without L. casei. Each treatment group consisted of four replicates and were maintained for 60 days. The research design used was Completely Randomized Design subjected to analysis of variant (ANOVA) followed by Duncan test. The feed conversion values of groups P0, P1, P2, and P3 were 4.46; 4.38; 4.21; and 4.54, respectively. The results showed that the feed conversion was not significant in all groups. It was concluded that L. casei fermenter could not improve the feed conversion ratio (FCR).Keywords: FCR, fermentation, kampung chicken, Lactobacillus casei, manure ABSTRAKBudidaya ayam kampung terkendala tingginya harga pakan dan rendahnya produktivitas. Penelitian ini bertujuan memanfaatkan pakan alternatif bersumber manur (limbah kotoran) ayam broiler untuk memperoleh pakan murah dengan kualitas baik. Manur broiler masih mengandung nutrisi yang tinggi. Manur difermentasi menggunakan Lactobacillus casei untuk memperbaiki konversi pakan. Dua ratus ekor ayam dibagi menjadi 4 kelompok (n=50 ekor). Kelompok P1, P2, dan P3 masing-masing diberi ransum yang ditambah fermentasi L. casei sebanyak 4%, 8%, dan 12%. Kelompok P0 diberikan pakan biasa tanpa penambahan L. casei. Setiap kelompok perlakuan terdiri dari empat ulangan dipelihara selama 60 hari. Penelitian menggunakan Rancangan Acak Lengkap (RAL) dengan analisis ragam yang dilanjutkan dengan uji Duncan. Kon

Fermented milk is a common beverage in many countries, but its flavor is highly variable from one region to another. The fermented mare milk, common beverage in Central Asia, has a typical flavor of koumiss, but those flavors were never described using aroma compound determination. In the present study, six lactic acid bacteria were identified in local koumiss. Due to the apparent technological advantage of Lactobacillus casei and Streptococcus thermophilus (notably their acidification speed), the main objective of this study was to compare their volatile compound profiles. 35 aromatic compounds were detected. To compare the aroma profiles of each strain, the ratio proportion strain/control was calculated for each strain and for each aroma showing significantly different profiles with predominance of 2-methyl-1-propanol and 2-undecanol in milk fermented with L. casei, and of 2,3-pentanedione in milk fermented with S. thermophilus. L. casei strain produced more aroma and its profile was significantly (P>0.03) different from S. thermophilus profile.

The interest about probiotic bacteria supplementation in fruit beverages has been increased recently in order to develop functional beverages without lactose. That is a technological challenge since pH and storage temperature can affect their viability. The aim of this study was to evaluate the viability of three commercial probiotic strains (L. paracasei, L. casei and L. rhamnosus) in mango beverage stored at 4°C. This research was developed in three stages: the assessment of the acid strain tolerance, the selection of a prebiotic as cellular protectant against environmental stress, the evaluation of physiochemical and sensory stability during storage. L. casei was chosen as the most stable strain with FOS at 5% as a prebiotic substance that stimulated its growth. At the final stage, it was found that L. casei produced significant changes in pH and titratable acidity in mango beverages after one week at 4°C, which was also detected by consumers with good sensory acceptance, La inclusión de bacterias probióticas en bebidas de frutas representa un gran reto tecnológico, debido a que la viabilidad de los microrganismos es afectada por varios factores, entre ellos el pH y la temperatura de almacenamiento. El objetivo de este trabajo fue evaluar la viabilidad de tres cepas probióticas comerciales (L. paracasei, L. casei and L. rhamnosus) en bebida de mango almacenada a 4°C. Esta investigación se desarrolló en tres etapas: evaluación ácido tolerancia de las cepas probióticas, selección sustancia prebiótica como protector celular y la estabilidad sensorial y físicoquímica de la bebida durante el almacenamiento. Se determinó que L. casei fue la cepa más estable en bebida de mango y FOS al 5% la sustancia que estimuló en mayor cantidad su crecimiento. Además, la inclusión de L. casei generó cambios significativos en el pH y la acidez titulable transcurrida una semana de almacenamiento a 4°C, los cuales fueron detectados por los consumidores

[EN] Probiotics are bacteria that can provide health benefits to consumers and are suitable to be added to a variety of foods. In this research, viability of immobilized Lactobacillus casei in alginate with or without sea buckthorn lipid extract were studied during heat treatment and with an in vitro gastrointestinal model. The characterization of the lipid extract was also done using the UV-Vis spectrometry (UV-Vis), high-performance liquid chromatography photodiode array detection method (HPLC-PDA), gas chromatography coupled with mass spectrometry (GS-MS) and Cryo scanning electron microscopy (Cryo-SEM). During heat treatment, the entrapped probiotic cells proved high viability (>6 CFU log/g), even at temperatures above 50 degrees C. The rich in monounsaturated fatty acids sea buckthorn fraction improved the in vitro digestion passage regarding the probiotic viability. The survival of the probiotic cells was 15% higher after 2 h in the acidic medium of the simulated gastric fluid in the sample where L. casei was encapsulated with the sea buckthorn extract compared with the samples where no extract was added. Thus, this approach may be effective for the future development of probiotic-supplemented foods as foods with health welfare for the consumers.

ObjectiveKawasaki disease (KD) is the leading cause of acquired heart disease among children in developed countries. Coronary lesions in KD in humans are characterized by an increased presence of infiltrating CD3+ T cells; however, the specific contributions of the different T cell subpopulations in coronary arteritis development remain unknown. Therefore, we sought to investigate the function of CD4+ and CD8+ T cells, Treg cells, and natural killer (NK) T cells in the pathogenesis of KD.MethodsWe addressed the function of T cell subsets in KD development by using a well-established murine model of Lactobacillus casei cell wall extract (LCWE)-induced KD vasculitis. We determined which T cell subsets were required for development of KD vasculitis by using several knockout murine strains and depleting monoclonal antibodies.ResultsLCWE-injected mice developed coronary lesions characterized by the presence of inflammatory cell infiltrates. Frequently, this chronic inflammation resulted in complete occlusion of the coronary arteries due to luminal myofibroblast proliferation (LMP) as well as the development of coronary arteritis and aortitis. We found that CD8+ T cells, but not CD4+ T cells, NK T cells, or Treg cells, were required for development of KD vasculitis.ConclusionThe LCWE-induced murine model of KD vasculitis mimics many histologic features of the disease in humans, such as the presence of CD8+ T cells and LMP in coronary artery lesions as well as epicardial coronary arteritis. Moreover, CD8+ T cells functionally contribute to the development of KD vasculitis in this murine model. Therapeutic strategies targeting infiltrating CD8+ T cells might be useful in the management of KD in humans.