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In the present research, the impact of fermentation with two strains of Lactiplantibacillus plantarum subsp. plantarum (PTCC 1896 and PTCC 1745) on physicochemical properties, antioxidant bioactive compounds, and some health‐promoting features of guava juice was investigated. Results showed a significant (p <.05) decrease in pH, total soluble solids, glucose and fructose residues, vitamin C, and total carotenoids after 32 h of fermentation. Total phenolic content, free radical scavenging abilities, and ferrous reducing power were markedly enhanced during the fermentation process. Moreover, fermented juice represented good enzyme inhibition abilities (α‐amylase and α‐glucosidase) and anti‐inflammatory activities. The initial amount of angiotensin‐converting enzyme inhibitory activity (26.5%) increased to 72.1% and 66.4% in L. plantarum subsp. plantarum 1896 and L. plantarum subsp. plantarum 1745 treatments, respectively. These findings reveal that guava juice fermentation with the studied Lactobacillus strains can be a promising strategy to augment the functional properties of the fruit‐based beverage. [ABSTRACT FROM AUTHOR]

This study examined the effect of beef fermentation with Lactiplantibacillus paraplantarum (L) PTCC 1965, Lactiplantibacillus (L) plantarum subsp. plantarum PTCC 1745, and Lactiplantibacillus (L) pentosus PTCC 1872 bacteria on the growth of pathogenic bacteria, including Salmonella (S) Typhi PTCC 1609 and Staphylococcus (S) aureus PTCC 1826. The growth of lactic acid bacteria (LAB) and the effect of fermentation on pathogenic bacteria were studied using Weibull: biphasic linear and competitive models. The results showed that the rate of pH reduction was lower in the early stages and increased as the microbial population grew. The α parameter was lower for L. plantarum subsp. plantarum compared to L. paraplantarum and L. pentosus. The comparison of the α parameter for bacterial growth and pH data showed that the time interval required to initiate the rapid growth phase of the bacteria was much shorter than that for the rapid pH reduction phase. The pH value had a 50% greater effect on the inactivation of S. Typhi when compared to the samples containing L. plantarum subsp. plantarum and L. pentosus. The same parameter was reported to be 72% for the inactivation of St. aureus. In general, during the fermentation process, LAB strains caused a decrease in pH, and as a result, reduced the growth of pathogens, which improves consumer health and increases the food safety of fermented meat. [ABSTRACT FROM AUTHOR]

Meat and some meat products are highly perishable due to their high-water content, pH, and high content of nutrients. Therefore, spoilage control in these products is one of the critical challenges in the food industry. On the other hand, the increasing widespread awareness about the undesirable effects of synthetic preservatives has promoted the breakthrough of the use of natural compounds or bio-preservation technology. Bio-preservation implies the application of microorganisms or their metabolites to extend the shelf life of food products. In this regard, according to the ancient and safe use of fermentation by lactic acid bacteria (LAB), their application in the bio-preservation of meat and meat products is gaining more attention. Thus, more understanding of the potential of LAB and their metabolites in the control of pathogens in meat and meat products can create new horizons in the production of safe and functional products with long shelf life. So, this article aims to review the recent knowledge about the bio-preservation of meat and meat products by LAB and their metabolites. Also, their antibacterial mechanism and potential for use in hurdle technology are discussed. The outcome of this review literature shows the high potential of various LAB strains and their metabolites especially bacteriocins as bio-preservatives in meat and meat products for extending their shelf life. In this regard, their combined use with other novel technologies or natural antibacterial compounds as hurdle technology is a more effective method that can compete with synthetic preservatives. [ABSTRACT FROM AUTHOR]

In this study, Limosilactobacillus fermentum PTCC 1638 and Lacticaseibacillus rhamnosus PTCC 1637 were used alone and in combination to ferment quinoa seeds, and the effect of fermentation (37 °C; 24 h) on the pH, total phenols, tocopherols, vitamin C, antioxidant activity, and enzymes inhibition (α-amylase and α-glucosidase; antidiabetic effect) was investigated. The results showed that with the increase in the fermentation time, the bacterial population, total phenols, antioxidant activity, and enzymes inhibition increased, which showed the greatest increase for the co-culture of L. rhamnosus and L. fermentum compared to the pure culture of each strain. Due to the increase in the fermentation time, the tocopherol isomers (α, β, γ, and δ), vitamin C, and pH decreased, and the largest decrease was related to the co-culture of the strains, followed by L. rhamnosus and L. fermentum. The results of this study showed that the co-culture and pure culture of bacteria can have different effects on the physicochemical properties and bioactive compounds of quinoa seeds. [ABSTRACT FROM AUTHOR]

In this study, ultrasonication (US) (50 W, 30 kHz, 1–6 min) was used to increase the efficiency of Limosilactobacillus reuteri PTCC 1655 fermentation process (37 °C; 30 h) of Bakraei juice. Total sugars, pH, Brix, organic acids, vitamin C, polyphenols, antioxidant activity, α-amylase inhibition and anti-inflammatory properties were measured during the fermentation period. The results showed that by increasing the ultrasound time up to 5 min, pH, vitamin C, citric acid, and polyphenolic compounds decreased, while lactic acid, antioxidant capacity, α-amylase inhibition and anti-inflammatory properties were increased. When the ultrasound time was increased up to 6 min, compared to the non-ultrasound-treated sample, the efficiency of the fermentation process decreased and promoted a decrease in the microbial population, lactic acid levels, antioxidant activity, α-amylase inhibition, and anti-inflammatory properties of the juices. The initial anti-inflammatory activity (11.3%) of juice reached values of 33.4% and 19.5%, after US treatments of 5 and 6 min, respectively, compared to the non-sonicated juice (21.7%), after 30 h of fermentation. As a result, the use of ultrasound in the controlled fermentation process can increase the efficiency of fermentation process. [ABSTRACT FROM AUTHOR]

Aflatoxin B1 (AFB1) is a hazardous component that can seriously threaten the public health. Terxine is a component used in traditional soup and found in the western mountainous regions of Iran. Several microorganisms have been reported to bind or degrade aflatoxins (AFs) in foods and feeds. This research aimed to investigate the effect of Terxine fermentation by  Lactobacillus plantarum  strains AF1 and LU5 on AFB1. Fermentation was carried out, and pH, lactic acid and AFB1 amount and microbial count were further determined. In addition, the kinetic experimental data of AFB1 by L. plantarum  AF1 and LU5 (obtained at 37°C) were fitted to the zero-order, first-order and parabolic diffusion models. According to the coefficient of determination (R2) and root mean square of errors (RMSE), the zero-order model best described AF degradation. The growth of Lactobacillus strains was increased by the rise in the fermentation time; in this regard, the number of L. plantarum AF1 increased from 4.2 to 5.1 log cfu/g and that of L. plantarum LU5 increased from 4.1 to 5.2 log cfu/g in the first 8 h, reaching 7.2 and 7.4 log cfu/g in the next 8 h, respectively. The results also showed that the amount of lactic acid increased whereas the pH value decreased during the 24 h fermentation. Both microorganisms reduced the amount of AFB1 while L. plantarum AF1 was more effective. Therefore, L. plantarum  strains AF1 and LU5 can be effectively used to reduce AFB1 in fermented foods. [ABSTRACT FROM AUTHOR]

In the present research, the effects of continuous ultrasound treatment (100 W, 30 kHz; 0%, 30%, 60% and 90% amplitudes, 15 min) and fermentation process (37°C, 24 h) on the growth of Lactobacillus plantarum LP3 and LU5 strains and bioactive properties (peptide content, α‐amylase and α‐glucosidase inhibition, anticancer and antioxidant activities and exopolysaccharide content) of goat milk were investigated. According to our results, the ultrasonication of milk up to 60% amplitude promoted the growth of Lactobacillus strains and enhanced the bioactive properties compared with control during fermentation, while, the ultrasonication at 90% amplitude had negative effects on the mentioned parameters. Exopolysaccharide content, α‐amylase inhibition, α‐glucosidase inhibition, antioxidant activity and anticancer activity of treated samples at 60% amplitude at the end of fermentation in comparison to its beginning were increased 18.09, 12.79, 12.44, 9.4 and 1.92 folds, respectively. Also, the increase of assayed characteristics was found strain‐dependent, so that L. plantarum LP3 was more effective than LU5 strain. [ABSTRACT FROM AUTHOR]

Summary: In the present study, the effects of continuous and pulsed ultrasound (100 W, 30 kHz, 25–75% amplitudes for 30 min) and fermentation process (37°C for 24 h) by Lactobacillus helveticus PTCC 1332 on biological activities of Chortan were investigated. The obtained results showed that fermentation enhanced protease content (36.27% (neutral), 37.57% (acid), 39.28% (alkaline) protease), peptide concentration (45.27%) and antioxidant activity (33.69% (DPPH), 132.85% (ABTS)) of samples compared to unfermented ones. Additionally, an increase in ultrasound amplitude (except for continuous at 75%) promoted the protease enzymes, peptides and radical scavenging activity of the fermented and unfermented samples. Our results indicated that the ultrasound and fermentation treatments complemented each other. Depending on the experimental conditions, the effect of continuous ultrasound on samples was sometimes lower, sometimes similar and sometimes higher than that of pulsed treatment. Therefore, selection of an appropriate ultrasound mode and amplitude can improve the biological activity of Chortan. [ABSTRACT FROM AUTHOR]

Abstract In the current study, the effects of three lactobacilli strains (L. plantarum subsp. plantarum PTCC 1745, L. fermentum PTCC 1638 and L. casei subsp. casei PTCC 1608) on phytic acid content, pH, lactate, total phenolic compounds as well as antioxidant activity of acorn dough during fermentation (37 °C for 24 h) were investigated. According to the results, the number of L. casei subsp. casei was significantly higher than those reported for two other strains during 24 h of fermentation (p-value ≤0.05). Moreover, the highest concentration of lactate and the lowest pH was observed in dough containing L. casei subsp. casei. The biggest decrease in the phytic acid content of dough was associated with fermentation by L. plantarum subsp. plantarum. Also, the phytase activity of L. plantarum subsp. plantarum , L. fermentum , and L. casei subsp. casei was measured at 2.77, 2.38 and 2.12 U/mg pro, respectively. Moreover, the highest antioxidant activity was achieved by the L. plantarum subsp. plantarum due to a higher concentration of phenolic compounds produced. Accordingly, among the three mentioned lactobacilli, the application of L. plantarum subsp. plantarum for fermentation of the acorn flour is recommended. Highlights • The efficiency LAB strains in fermentation of acron flour was evaluated. • A notable reduction in phytic acid content was achieved by acron flour fermentation. • Highest performance was associated with L. plantarum subsp. plantarum fermentation. • Fermentation by LAB improved the antioxidant activity of acron flour. [ABSTRACT FROM AUTHOR]

Date syrup is rich in fermentable sugars and may be used as a substrate for different microbial fermentations, including lactic acid fermentation processes. The beneficial effects of ultrasounds (US) on bioprocesses have been reported for several microorganisms, due to the enhancement of cell growth, as well as improvements in yields and productivities. Therefore, US treatments (30 kHz, 100 W, 10–30 min) were applied to two lactobacilli (Lactobacillus helveticus PTCC 1332 and Lactobacillus acidophilus PTCC 1643), during fermentation using date syrup as substrate. The effects on lactic acid fermentation were evaluated by analyzing cell growth (dry cell weight and viable cell count), substrate consumption (quantification of glucose and fructose), and product formation (quantification of lactic acid) over time. The effects of US were also evaluated on cell membrane permeability. Both lactobacilli were able to grow well on date syrup without the need for addition of further ingredients. The US effects were highly dependent on treatment duration: treatments of 10- and 20-min stimulated lactobacilli growth, while the treatment extension to 30 min negatively affected cell growth. Similarly, the 10- and 20-min treatments increased sugar consumption and lactic acid production, contrarily to the 30-min treatment. All US treatments increased cell membrane permeability, with a more pronounced effect at more extended treatments. The results of this work showed that application of appropriate US treatments could be a useful tool for stimulation of lactic acid production from date syrup, as well as for other fermentative processes that use date syrup as substrate. [ABSTRACT FROM AUTHOR]

BACKGROUND The antioxidant and antibacterial activities of fermented sarshir (traditional dairy food), with three probiotic Lactobacillus plantarum strains (LP3, AF1, and LU5), were investigated. The oxidative stability and the lipid profile of non-fermented and fermented sarshir were compared, in addition to radical scavenging activity, as well as peroxide, anisidine and carbonyl values (PV, AnV and CV, respectively). RESULTS The strong antibacterial activity of fermented sarshir against common pathogenic bacteria, including Gram-negative Escherichia coli O157: H7 ATCC 35150 and Pseudomonas aeruginosa ATCC 27853, as well as Gram-positive Bacillus cereus ATCC 10876 and Staphylococcus aureus ATCC 25923, was established. Among the strains examined, L. plantarum LP3 exhibited the highest radical scavenging activity (53.1 ± 1.8%) and lowest PV (3.0 meq kg-1), AnV (1.31 ± 0.06) and CV (1.4 ± 0.08). The pH of sarshir decreased from 6.2 ± 0 to 3.5 ± 0.1 during 14 h of fermentation. Incorporated bacterial cells exhibited notable viability during 10 days of cold storage (4 °C). CONCLUSION The fermentation of sarshir by L. plantarum strains, especially LP3, resulted in beneficial changes in radical scavenging activity, as well as PV, AnV and carbonyl values, in addition to a broad spectrum of inhibitory activity against strains of P. aeruginosa, E. coli O157:H7, B. cereus and S. aureus. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

[Display omitted] • Lactobacillus strains showed antimicrobial activity against S. flexneri. • Lactobacillus strains increased antioxidant capacity of peach juice. • Fermentation with Lactobacillus strains decreased Maillard reaction in peach juice. • Lactobacillus strains improved the anti-inflammatory activity. The purpose of the current study was to evaluate the antimicrobial activity of Lactobacillus acidophilus PTCC 1643 and Lactobacillus fermentum PTCC 1744 against Shigella flexneri PTCC 1865 in fermented peach juice, as well as the anti-adhesion ability on epithelial Caco-2 cells. Moreover, the biological activities of peach juice were examined. We found that the studied Lactobacillus strains effectively inhibited the growth of S. flexneri during the peach juice fermentation. In addition, L. acidophilus revealed more anti-adhesion ability than L. fermentum. The inhibition of the Maillard reaction increased from 4.10% to 36.70% and 33.00% in L. acidophilus and L. fermentum treatments, respectively. Additionally, the ferrous reducing power, superoxide anion antiradical and anti-inflammatory activities of the beverage augmented during the fermentation period. These findings may be helpful for inhibition of foodborne pathogens by Lactobacillus strains and production of fruit-based fermented beverages with high functional and nutritional value. [ABSTRACT FROM AUTHOR]

The individual and combined effects of ultrasound, microwave, and heat treatment of milk on L. acidophilus viability, lactate concentration and bioactive properties (radical scavenging capacity, proteases activities, peptide level, anticancer activity, α-amylase inhibition and exopolysaccharide content) during fermentation were investigated. It was notable that Lactobacillus acidophilus exhibited by far the best growth in microwave treated samples, while ultrasonicated microwaved samples had higher antioxidant and anticancer activities. The antioxidant activity of ultrasonicated microwaved milk at the end of fermentation was 13.9%, 44.7% and 77.3% higher than that of ultrasonicated autoclaved, microwaved and autoclaved samples, respectively. After 24 h fermentation, the average protease activity of the microwaved milk was 1.3–1.8 times more than the observed values in the other treated samples. The amount of exopolysaccharide, anticancer activity and α-amylase inhibition of ultrasonicated microwaved milk, especially after 8 h fermentation, were also significantly higher than those of the other treated milks. [ABSTRACT FROM AUTHOR]

In this study, bergamot juice was fermented with pure and mixed cultures of L. plantarum subsp. plantarum PTCC 1896, L. plantarum AF1 and L. plantarum LP3 to make a fermented drink. Viable cell count, chemical composition, DPPH radical-scavenging activity and overall acceptance were studied during 72 h of fermentation and compared with the control sample. Results indicated that mixed ternary cultures had the highest growth resulting in higher microbial population compared to binary co-cultures followed by sole inoculation. Bergamot juices from ternary combination fermentation followed by PTCC-LP3 and AF1-LP3 binary combinations had markedly higher pH, glucose and fructose consumption, lactic acid and formic acid production, citric acid usage and radical-scavenging effect compared to single culture of L. plantarum strains and the control sample after the fermentation period. In contrast, no significant differences were observed between the samples in ascorbic acid content, with the initial value reaching from 266.3 mg/100g to about 231.6 mg/100g after 72 h of fermentation, indicating that the fruit juice is still a good source of ascorbic acid. Regarding general acceptance, all fermented juices received scores (ranging from 6.6 to 7.4) above the acceptability limit (6). Overall, since bergamot juice with selective fermentation had more antioxidant properties than the control sample fermented with natural flora and was also acceptable to the panelists, so fermentation of bergamot juice with selective combination of L. plantarum strains is recommended. This study provides new insights into fruit-based fermented non-dairy beverages production. • Bergamot juice was a good food matrix for production of fermented juice. • Efficacy of the L. plantarum strains was dependent on both strain and inoculation. • Antioxidant capacity of bergamot juice was increased by L. plantarum fermentation. • Mixed ternary cultures had the highest lactic and formic acid production. • No significant decrease of ascorbic acid was observed in pure and mixed fermentation. [ABSTRACT FROM AUTHOR]

The effect of ultrasound (100 W, 30 kHz, 25% amplitude for 5, 10, and 15 min; US) on growth, carbohydrate metabolism, and antioxidant activity of probiotic Lactobacillus plantarum AF1 was investigated during milk fermentation. The antioxidant activity of L. plantarum AF1 was measured by 2,2′‐azinobis‐(3‐ethylbenzothiazoline‐6‐sulfonate) (ABTS), 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH), inhibition of the autoxidation of ascorbate, reducing ability, and superoxide anion radical scavenging activity tests. The results indicated that the cell membrane permeability of sonicated samples was increased 88–94% compared to control. Additionally, β‐galactosidase activity and population of Lactobacillus strain increased with increasing ultrasound treatment time during the fermentation after the treatment. However, no significant differences were observed in the final counts of the control and the sonicated samples at the end of fermentation (24 hr). Although the lactose content was decreased significantly (p ≤ .05) by extending sonication time, the amounts of glucose, galactose, and lactic acid enhanced significantly (p ≤ .05) as the time of fermentation and sonication proceeded. The antioxidant activity was also enhanced significantly (p ≤ .05) with increase in sonication time during 24 hr fermentation after the treatment. Therefore, the lowest and the highest antioxidant activities were seen in the control sample and the US‐15 min sonicated milk at the end of fermentation, respectively. Practical applications: The dairy industry is seeking methods to increase nutritional and quality of dairy products. Recently, the ultrasound has attracted significant attention in food processing generally because of the recent consumers' trend toward functional foods. The present study provides an investigation about the efficiency of ultrasound to improve the metabolism and growth of Lactobacillus plantarum during fermentation of milk and therefore increase the quality and antioxidant activity of milk. The results show that ultrasound is a potential technique for improve metabolism of Lactobacillus strain and thus increase antioxidant activity and quality of fermented milk. Consequently, the use of ultrasound will increase the health promoting effects and quality of fermented dairy products. These results will assist in designing ultrasound procedures for optimizing the general quality of fermented milk. [ABSTRACT FROM AUTHOR]