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Zn treatment effects on the stability of polyphenols, MDA (malondialdehyde) content, antioxidant and lipoxygenase inhibition activities of two varieties of fennel bulbs were studied by using an in vitro gastrointestinal digestion model. Likewise, the effect of Zn on viability cells of E. coli was also performed. The results revealed that high amounts of total phenolic and flavonoid compounds were released during the digestion process, especially after the intestinal phase. Additionally, the antioxidant and lipoxygenase inhibitory activity were affected by the gastrointestinal digestion process and seems to be correlated with total phenol contents. On the other hand, the viability of E. coli was not affected by the activity of our tested bulbs during passage through the artificial digestion model, but the treated bulbs activity contribute relatively to the inhibition growth of bacteria. The survival of E. coli in fennel bulbs was challenged with simulated gastrointestinal fluids and the results showed that the E. coli strains, despite having experienced a viability reduction at the intestinal phase, were able to overcome the exposure to the gastrointestinal synthetic fluids. This E. coli ability reinforces the need for good hygienic measures to assure safe fresh produce, even for those that are rich in antibacterial compounds. info:eu-repo/semantics/publishedVersion

The effects of coating 'Rocha' pear with alginate-based nanoemulsions enriched with lemongrass essential oil (LG) was evaluated and compared to the usual 1-MCP treatment. Fruit were treated with 1-MCP (312 nL L-1) or coated with nanoemulsions: sodium alginate 2 % (w/w) + lemongrass essential oil 1.25 % (w/w) (LG 1.25 %) or lemongrass essential oil 2.5 % (w/w) (LG 2.5 %). Then, fruit were stored at 0 degrees C and 90-95 % relative humidity (RH), for eight months. Fruit samples were collected at harvest and after two, four, six and eight months of cold storage, and then transferred to shelf-life at 22 degrees C. Upon removal and after 7 d shelf-life, fruit symptoms of superficial scald and internal browning, ethylene production, color CIE (L*, hue), firmness, soluble solids content (SSC), titratable acidity (TA), weight loss, electrolytic leakage (EL), antioxidant activity and fatty acids of pear peel, microbial growth and sensory analyses were evaluated. Coatings and 1-MCP reduced fruit color evolution and preserved better firmness than control. Coatings and 1-MCP did not affect SSC and TA. Treatments did not influence the sensory quality. Microbial growth was within the safety limits in all treatments. Treatments with 1-MCP and LG-nanoemulsions were similarly efficient to reduce superficial scald, nevertheless the LG-nanoemulsions showed higher internal disorders after 8 months of storage and LG 2.5 % had higher decay at the same period, similar to control. 1-MCP treated fruit had the lowest softening rate after shelf-life up to 4 months and LG 2.5 % showed higher weight loss. Also, ethylene production was higher in control and LG 1.25 % up to 6 months plus shelf-life, while after 8 months there was no difference among treatments. This study suggests that 1-MCP is the most efficient for preserving quality of 'Rocha' pear for 8 months, while up to 6 months the best effect is obtained with LG 1.25 % nanocoatings. info:eu-repo/semantics/publishedVersion

To evaluate the antioxidant activity of fourteen essential oils (EOs) isolated from myrtle (Myrtus communis L.) collected at different regions of Algeria, seven different assays were carrie...

Interest in the use of essential oils (EOs) in the biomedical and food industries have seen growing over the last decades due to their richness in bioactive compounds. The challenges in developing an EO extraction process that assure an efficient levels of monoterpenes with impact on biological activities have driven the present study, in which the EO extraction process of rosemary, lavender and citrus was performed by simultaneous hydrodistillation–steam distillation, and the influence of EO composition on biological activities, namely antioxidant, anti-inflammatory, antidiabetic, anti-acetylcholinesterase, anti-tyrosinase, antibacterial, and antibiofilm activity, were evaluated. The EO yields of combinations were generally higher than the individual plants (R. officinalis (Ro), L. angustifolia (La), and C. aurantium (Ca)) extracted by the conventional hydrodistillation. The EOs obtained by this process generally had a better capacity for scavenging the free radicals, inhibiting α-glucosidase, and acetylcholinesterase activities than the individual EOs. The combination of EOs did not improve the ability for scavenging peroxide hydrogen or the capacity for inhibiting lipoxygenase activity. The antioxidant activity or the enzyme inhibition activity could not only be attributed to their major compounds because they presented lower activities than the EOs. The chemical composition of the combination Ro:La:Ca, at the ratio 1/6:1/6:2/3, was enriched in 1,8-cineole, linalool, and linalyl acetate and resulted in lower MIC values for all tested strains in comparison with the ratio 1/6:2/3:1/6 that was deprived on those components. The biofilm formation of Gram positive and Gram negative bacteria was impaired by the combination Ro:La:Ca at a sub-inhibitory concentration.

In our previous study the enrichment of the intestinal proteome of type 1 diabetes (T1D) children with Bacteroides proteins was observed, which led us to our current study that aimed to isolate and characterize Bacteroides species from fecal samples of T1D and control children. Repetitive sequence-based PCR (rep-PCR) was used for typing the isolated Bacteroides species. The antibiotic susceptibility and mucinolytic activity of the isolates was determined. The quantification of specific bacterial groups in the fecal samples was determined by qPCR. The ability to adhere and invade the human colonic cell line HT29-MTX-E12 of strains of P. dorei, B. uniformis and P. distasonis was determined and their whole genome sequencing was performed. The results showed similar numbers of Bacteroides species in T1D and control samples, but unique Bacteroides species and a higher recovery of P. distasonis from T1D samples was observed. Rep-PCR grouped the different Bacteroides species, but no discrimination by origin was achieved. T1D children showed a significant increase in Proteobacteria and a depletion in Lactobacillus sp. All tested P. dorei, B. uniformis and P. distasonis were able to adhere to HT29-MTX-E12 cells but significant differences (p < 0.05) in the ability to invade was observed. The highest ability to invade was exhibited by P. distasonis PtF D14MH1 and P. dorei PtFD16P1, while B. uniformis strains were unable to invade. The damage to tight junctions was also observed. The presence of Lactobacillus sp. inhibited the invasion ability of P. distasonis PtF D14MH1 but not P. dorei PtFD16P1. Sequences of agonist peptides of the human natural preproinsulin and the insulin B chain insB:9-23 peptide mimics were identified. The results reported in our study stresses the continued efforts required to clarify the link between T1D and gut microbiota.

The consumption of snacks based on fruit has increased in the last years due to consumer awareness of health issues and the nutritional benefits of fruit. The aim of this work was to develop a snack with high fruit content based on kiwifruit (Actinidia chinensis var. deliciosa 'Hayward') and to evaluate the effect of different active packaging on its quality through storage. A snack was developed made of kiwifruit pulp mixed, in equal proportions, with pectin solution (4% pectin + 1% ascorbic acid), then with natural yogurt in a proportion of 3:1 to which stevia powder at 5% was added. The final mixture was poured into baking foil, in ~2-mL portions, and dried at 40°C for 48 h. After drying, snacks were stored in active packaging paper bags (120 g m-2) of the following composition: paper enriched with alginate 1 or 2%; paper enriched with alginate 1% plus Glycix 70% or 2% plus Glycix 70%; control (non-treated paper). Measurements of microbial content, color (L*C*h°), crispness, water activity and sensory panels were performed. Results showed that the snacks were of good nutritional quality and were appreciated by the sensory panel. Through storage, there were no significant differences between active packaging for most of the quality parameters studied. Nevertheless, alginate 1% performed better in terms of appearance, control samples showed slightly higher microbial spoilage after 4 months and appearance decreased from 3 to 4 months. Further studies are needed to improve these packages.

The aim of this work was to study the potential of two halophytes for fresh salads. Sarcocornia perennis (SAR) and Salicornia ramosissima (SAL) plant tips were harvested in May and July, and stored at 4 &deg, C for 14 days. At harvest, mineral analyses (Na, K, Mg, Ca, P, N, Fe, Zn, Cu, Pb and Cd), chlorophyll content, protein, &beta, carotene and ascorbic acid were performed. Color (CIELab), phenolics, antioxidant activity and microbial contamination were measured at harvest and after 14 days storage at 4 &deg, C, and a taste panel evaluated the products. SAL had generally slightly higher values of vitamin C, phenols and carotenoids than SAR. In SAR after 14 days of storage, the levels of phenols and the antioxidant activity were higher than at harvest, both in May and July. The opposite was observed for SAL. In this case, only the antioxidant activity was higher after 14 days of storage. Microbial contamination was very low, not reaching even half of critical limits. Both halophytes had good nutritional value, being suitable for use as fresh salads which can be stored for up to 14 days at 4 &deg, C. SAR seems to be a better source of antioxidants, Ca and Fe than SAL and has less general quality and nutritional value changes from harvest time through cold storage. Fresh tips of both halophytes showed better appearance and nutritional quality when harvested in the early season (May) than at the end of the season (July).

Nature has offered us a tremendous diversity of natural compounds, for which antimicrobial and antioxidant properties have been intensively explored and nowadays are plenty recognized [...]

The effect of coating &lsquo, Rocha&rsquo, pears with alginate-based nanoemulsions enriched with lemongrass essential oil (LG) or citral (Cit) was investigated. Fruit were treated with the nanoemulsions: sodium alginate 2% (w/w) + citral 1% (w/w) (Cit1%), sodium alginate 2% (w/w) + citral 2% (w/w) (Cit2%), sodium alginate 2% (w/w) + lemongrass 1.25% (w/w) (LG1.25%), sodium alginate 2% (w/w) + lemongrass 2.5% (w/w) (LG2.5%). Then, fruit were stored at 0 &deg, C and at 95% relative humidity, for six months. Fruit samples were taken after two, four and six months, and then placed at 22 &deg, C. Upon removal and after 7 d shelf-life, fruit were evaluated for colour CIE (L*, h◦), firmness, soluble solids content (SSC), titratable acidity (TA), weight loss, electrolytic leakage, microbial growth, symptoms of superficial scald and internal browning. All nanoemulsions had droplets in the nano range &lt, 500 nm, showed uniformity of particle size and stable dispersion. Cit-nanoemulsions had lower droplet size and higher stability than LG. No nanoemulsion showed cytotoxicity. Coatings reduced fruit colour evolution and preserved better firmness than control. After shelf-life, better firmness was found in LG-coated fruit. Coatings did not affect SSC and TA. Microbial growth was below the safety limits in all treatments. Fruit treated with LG-nanoemulsions did not show scald symptoms and panelists preferred LG1.25% coated fruit. Cit2% treated fruit showed the highest scald and internal browning symptoms, while LG1.25% did not show any disorders. This study suggests that LG-nanocoatings have the potential for preserving the quality of &lsquo, pear.

In Portugal, beekeeping activity has a significant weight among livestock production. The antimicrobial activities of Portuguese honeys have been reported, but the anti-biofilm formation and anti-virulence abilities have not been investigated. The main goal of this work was to study the impact of three monofloral honeys (citrus, lavender and strawberry tree) honeys on adherence of Staphylococcus aureus, methicillin-resistant S. aureus (MRSA) and Pseudomonas aeruginosa, as well as the influence of the same honeys on virulence using Galleria mellonella as a model. In addition, the general physico-chemical characterization of these honeys and the microbial quality were also performed. The anti-inflammatory activity was also estimated by analyzing the activity of the enzymes hyaluronidase and lipoxygenase. The tested honeys complied with European legislation and no microbial contamination was observed. Of all the honeys at 12.5 and 25%, w/v the citrus honey caused the highest inhibitory activity against P. aeruginosa. Strawberry tree honey at 25% w/v was able to significantly inhibit the MRSA strains. Anti-biofilm formation and anti-inflammatory activities were observed. The different honeys impaired the virulence of S. aureus and MRSA strains. The Portuguese honeys were capable of combating the tested bacterial pathogens not only by inhibiting their growth but also by affecting important pathogenicity properties, such as adherence and virulence.

Magnetite nanoparticles (MNPs) have been evaluated for inhibiting microbial growth and biofilm for- mation. In this study the effect of the nanocomposite Moroccan propolis extract / MNPs acting against methicillin resistant strains of Staphylococcus aureus (MRSA) was evaluated. Chemical composition of propolis was established by pyrolysis coupled to gas chromatography and mass spectrometry method (pyrolysis GC/MS). MNPs were obtained through the co-precipitation method. The fabricated nanostruc- ture was characterized by X-ray Diffraction (DRX), Transmission Electron Microscopy (TEM), and Fourier Transform-Infrared Spectroscopy (FTIR). TEM of MNPs provided a particle average size of 15 nm, FTIR spectral analysis enabled a fast way of identification of MNPs, attesting the occurrence of the different combinations. The use of MNPs loaded with propolis and the antibiotic chloramphenicol at Minimum Inhibitory Concentration (MIC) value inhib- ited the bacterial growth of MSSA (methicillin susceptible strain of S. aureus ) and MRSA strains. After the treatment with MNPs-OA-P-CLo nanocomposite (MNPs with oleic acid, propolis and chloramphenicol), the disruption of the bacterial cell was observed by TEM. The combination of propolis and chlorampheni- col in free form at MIC value largely impaired both MSSA and MRSA strains as, after 2 h of treatment, no viable cells of MRSA 2 and MRSA 16 were recovered. Hence, the results elucidated a new antibac- terial nanocomposite synthesis, for possible applications as prospective nanoantibacterial agents or drug carriers. Fundação para a Ciência e Tecnologia with the project UID/Multi/04 4 49/2013 (POCI-01-0145-FEDER-007649); UID/BIA/04325/2013–MEDTBIO, UID/BIM/04773/2013 CBMR, UID/QUI/04023/2016, UID/QUI/0 010 0/ 2013, CQE. info:eu-repo/semantics/publishedVersion

Proteomics was applied here to study Listeria monocytogenes response to gastrointestinal stress. It separated extracted proteins by their isoelectric point (pI) in the first dimension followed by separation by molecular weight in the second dimension on a polyacrylamide gel. L. monocytogenes was grown in an appropriate culture medium after which it was transferred to a simulated cheese medium for 2 h. Bacteria were exposed to gastric stress using artificial saliva and gastric fluid for 5 min and 2 h, respectively. After each step samples were taken for protein extraction and a two-dimensional electrophoresis approach. Proteins were separated on 18 cm Immobiline DryStrip gels with a pH range of 4-7 and the protein pattern analyzed.

Proteomics was applied here to study Listeria monocytogenes response to gastrointestinal stress. It separated extracted proteins by their isoelectric point (pI) in the first dimension followed by separation by molecular weight in the second dimension on a polyacrylamide gel. L. monocytogenes was grown in an appropriate culture medium after which it was transferred to a simulated cheese medium for 2 h. Bacteria were exposed to gastric stress using artificial saliva and gastric fluid for 5 min and 2 h, respectively. After each step samples were taken for protein extraction and a two-dimensional electrophoresis approach. Proteins were separated on 18 cm Immobiline DryStrip gels with a pH range of 4-7 and the protein pattern analyzed.

The metabolic syndrome is a complex entity comprised of multiple cardiovascular risk factors grouped in a single individual, contributing to an increased rate of cardiovascular events which goes beyond what would be expected given the impact of each individual risk factor. It is a multifactorial condition whose complete pathogenesis is not yet fully understood. Several studies have shown that not only the intestinal microbiota and dysbiosis may play a role in its pathogenesis, but also that modulating said microbiota may play a role in treating or at least ameliorating the metabolic syndrome. The purpose of this article is to review some of the most recent evidence linking the gut microbiome and the metabolic syndrome to help further understand this relationship and try to identify further research directions.

The objective of the present work was to develop strategies for increasing the shelf-life of red raspberries (Rubus idaeus L.), by preventing microorganism growth.; Results: Fruits coated with alginate plus lemon essential oil (0.2%) or orange essential oil (0.1%) after 15 days of storage had less red skin than the remaining samples. The less red color verified in these samples was also coincident with the lower concentration of anthocyanins at the end of the experiment as well as the lower capacity for scavenging ABTS free radicals or quenching singlet oxygen. Cyanidin and pelargonidin glucosides were found in raspberries fruits. The edible coatings supplemented with the essential oil of orange either at 0.1% or 0.2% were very efficient for controlling yeast and mold growth after 15 days of storage. To control the development of aerobic mesophilic bacteria the use of essential oil of lemon 0.2% and essential oil of orange 0.1% were the most efficient.; Conclusion: The application of the film improved post-harvest quality of raspberry, since the addition of essential oils of citrus films promoted to the inhibitory effect of fungi and bacteria growth after 15 days of storage, without changing quality parameters. © 2016 Society of Chemical Industry.; © 2016 Society of Chemical Industry.

Edible coating formulations have been developed to increase shelf-life of some horticultural products. The objective of this research was to study the effect of edible coatings based on sodium alginate (AL) and pectin (PE) enriched with essential oils constituents (citral and eugenol) on the shelf-life extension of strawberries. AL and PE were tested at 1 and 2% (w/v) and were enriched with eugenol (Eug) at 0.1 and 0.2% and citral (Cit) at 0.15 and 0.3%. Strawberries were dipped in those solutions for 2 min, then stored at 0.5 °C. Measurements of color CIE (L*, a*, b*, h°, C*), firmness, soluble solids content (SSC), weight loss, trolox equivalent antioxidant capacity (TEAC), microbial growth and taste panels were accomplished at 0, 7 and 14 d storage. With those quality characteristics, hierarchical cluster analysis formed 3 groups either for AL or PE based edible coatings. Taking into account the mean closest values to the one at harvest for color, higher value for firmness, SSC and antioxidant activity, and lower value for weight loss and microbial spoilage, the best group was selected. From the selected groups, the 2 edible coating formulations which had higher score on taste panels were considered the best for preserving quality through shelf-life of strawberries. Those edible coatings were for AL the AL 2% + Eug 0.1%; AL 2% + Cit 0.15% + Eug 0.1% and for PE the PE 2% + Eug 0.1%; PE 2% + Cit 0.15%.

Essential oils are complex mixtures of volatile compounds with diverse biological properties. Antimicrobial activity has been attributed to the essential oils as well as their capacity to prevent pathogenic microorganisms from forming biofilms. The search of compounds or methodologies with this capacity is of great importance due to the fact that the adherence of these pathogenic microorganisms to surfaces largely contributes to antibiotic resistance. Superparamagnetic iron oxide nanoparticles have been assayed for diverse biomedical applications due to their biocompatibility and low toxicity. Several methods have been developed in order to obtain functionalized magnetite nanoparticles with adequate size, shape, size distribution, surface, and magnetic properties for medical applications. Essential oils have been evaluated as modifiers of the surfacemagnetite nanoparticles for improving their stabilization but particularly to prevent the growth of microorganisms. This review aims to provide an overview on the current knowledge about the use of superparamagnetic iron oxide nanoparticles and essential oils on the prevention of microbial adherence and consequent biofilm formation with the goal of being applied on the surface of medical devices. Some limitations found in the studies are discussed. info:eu-repo/semantics/publishedVersion

Spray-drying stands as one of the most used techniques to produce inhalable microparticles, but several parameters from both the process and the used materials affect the properties of the resulting microparticles. In this work, we describe the production of drug-loaded chondroitin sulphate microparticles by spray-drying, testing the effect of using different solvents during the process. Full characterisation of the polymer and of the aerodynamic properties of the obtained microparticles are provided envisaging an application in inhalable tuberculosis therapy. The spray-dried microparticles successfully associated two first-line antitubercular drugs (isoniazid and rifabutin) with satisfactory production yield (up to 85%) and drug association efficiency (60%&ndash, 95%). Ethanol and HCl were tested as co-solvents to aid the solubilisation of rifabutin and microparticles produced with the former generally revealed the best features, presenting a better ability to sustainably release rifabutin. Moreover, these presented aerodynamic properties compatible with deep lung deposition, with an aerodynamic diameter around 4 &mu, m and fine particle fraction of approximately 44%. Finally, it was further demonstrated that the antitubercular activity of the drugs remained unchanged after encapsulation independently of the used solvent.

[Background]: Essential oils (EOs) have shown antimicrobial, antioxidant, and antiproliferative activity, which may, alone or in combination with other substances, potentially be used for the development of new drugs. However, their chemical variability, depending on the species, varieties, or geographical origin (among other factors) determines different bioactivities that need to be evaluated., [Methods]: The antioxidant activity of Corymbia citriodora and eight Eucalyptus species EOs was determined using two different methods: the scavenging ability of 2,20-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS+•) and peroxyl free radicals or oxygen radical absorbance capacity (ORAC). Antibacterial activity was evaluated using the microorganisms Streptococcus pneumoniae (strains D39 and TIGR4), and Haemophilus influenza (strain DSM 9999). The essential oils’ minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) was assessed using a microdilution method. The antiproliferative activity was determined using the THP-1 cell line (human acute monocytic leukaemia) with methylthiazolyldiphenyl-tetrazolium bromide assay (MTT)., [Results]: Corymbia citriodora and Eucalyptus viminalis EOs showed the highest ABTS and peroxyl free radical scavenging capacity. Eucalyptus globulus EO showed a high potential to treat Streptococcus pneumoniae infections. Haemophilus influenzae was the respiratory pathogen that showed the highest resistance to all EOs, including tea tree EO. After 96 h of incubation, at 25 µg/mL, Eucalyptus radiata and Eucalyptus viminalis EOs showed highest cytotoxic activity against the THP-1 cell line., [Conclusions]: Despite their specific bioactivities, no single EO showed simultaneously good antioxidant, antimicrobial, and antiproliferative activity., This study was partially funded by CESAM (UID/AMB/50017-POCI-01-0145-FEDER-007638), to FCT/MCTES through national funds (PIDDAC), and co-funding by the FEDER within the PT2020 Partnership Agreement and Compete 2020, and by the Fundação para a Ciência e a Tecnologia (FCT), under the projects UID/BIA/04325/2013—MEDTBIO, and UID/BIM/04773/2013 CBMR

Honey with Bupleurum spinosum (zandaz) as a main pollen source has not been the subject of previous detailed study. Therefore, twelve Moroccan samples of this honey were subjected to melissopalynological, physicochemical and microbiological quality characterization, as well as antioxidant activity assessment. From a quality point of view, almost all samples were within the limits established by Codex Alimentarius, and/or the European legislation. All samples presented predominance of B. spinosum pollen (more than 48%). Relatively high levels of trehalose (1.3–4.0 g/100 g) and melezitose (1.5–2.8 g/100 g) were detected. Those sugars, not common in monofloral honeys, could be used as an important factor to discriminate zandaz honey. Flavonoid content correlated positively with the honey color, melanoidin and polyphenol content, and negatively with the IC50values of scavenging ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) free radicals, while proline amount correlated negatively with IC50values of nitric oxide scavenging activity and chelating power. This correlation supports the use of anti-oxidant activities as important variables for PCA (principal component analysis). Both components explained 70% from the given data, and showed certain homogeneity upon analyzed samples independent of the region, suggesting the importance of B. spinosum nectar in the resulting honey characteristics. The authors are grateful to Fundação para a Ciência e Tecnologia for Research Center Grant UID/BIM/04773/2013 CBMR 1334; UID/AGR/00239/2013; UID/BIA/04050/2013 (POCI-01-0145-FEDER-007569); and to ERDF through the COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI). info:eu-repo/semantics/publishedVersion

This study was performed to evaluate the total phenols, flavonoids, and antioxidant activities of twenty-four propolis samples from different regions of Morocco. In addition, two samples were screened regarding the antibacterial effect against four Staphylococcus aureus strains. Gas chromatography coupled to mass spectra (GC-MS) analysis was done for propolis samples used in antibacterial tests. The minimum inhibitory and minimum bactericidal concentration (MIC, MBC) were determined. The potential to acquire the resistance after sequential exposure of bacterial strains and the impact of adaptation to propolis on virulence using the Galleria mellonella were evaluated. Additionally, the effects of propolis extract on the bacterial adherence ability and its ability to inhibit the quorum sensing activity were also examined. Among the twenty-four extracts studied, the samples from Sefrou, Outat el Haj, and the two samples marketed in Morocco were the best for scavenging DPPH, ABTS, NO, peroxyl, and superoxide radicals as well as in scavenging of hydrogen peroxide. A strong correlation was found between the amounts of phenols, flavonoids, and antioxidant activities. Propolis extract at the MIC value (0.36 mg/mL) significantly reduced (p < 0.001) the virulence potential of S. aureus ATCC 6538 and the MRSA strains without leading to the development of resistance in the sequence of continuous exposure. It was able to impair the bacterial biofilm formation. The results have revealed that sample 1 reduces violacein production in a concentration dependent manner, indicating inhibition of quorum sensing. This extract has as main group of secondary metabolites flavonoids (31.9%), diterpenes (21.5%), and phenolic acid esters (16.5%).

The effects of optimized edible coatings based on sodium alginate (AL) or pectin (PE) with the essential oil constituent additives, citral (Cit) and eugenol (Eug), were studied on fresh raspberries quality during storage at 0.5 °C. Several formulations of edible coatings were used as treatments: AL and PE were tested at 1% and 2% (w/v) with Cit and Eug at minimum inhibitory concentrations (MIC) (0.15 and 0.1%, respectively), at double the MIC concentration and their combination at MIC. Raspberries were immersed in each solution (treatment) for 2 min, and then cooled at 0.5 °C. On days 0, 7, and 14th, samples were removed and used for the following physicochemical and biochemical analysis: color CIE ( L *, °hue), firmness, soluble solids concentration (SSC), weight loss, trolox equivalent antioxidant capacity (TEAC), microbial growth, and taste panels. Color parameter L * and TEAC were not significantly affected by the coatings. Cit at higher concentrations reduced °hue and firmness and increased weight loss. The SSC decreased mainly in controls. Edible coatings enriched with Cit and Eug were effective at reducing microbial spoilage. Taste panels showed lower scores in Cit 0.3% treatments and raspberries were considered not acceptable after 14 days storage. No significant differences were observed between PE and AL. Raspberries immersed in water (control + water) performed worse than fruit stored without any immersion or wash (control). With the results of the physicochemical and biochemical parameters measured, 3 similar treatment groups were formed by the principal component analysis (PCA) and hierarchical cluster analysis (HCA), either for AL or PE coatings. The group which had better performance was selected for AL- and PE-based edible coatings. From each group the two best edible coating formulations with the higher sensory evaluation were selected. Those confirmed that raspberries were better preserved in terms of general sensory attributes with coatings of AL 2% + Cit 0.15% and AL 2% + Eug 0.1%, and with PE 1% + Eug 0.1% followed by PE 1% + Cit 0.15% + Eug 0.1%.

Dairy products, in particular soft cheeses, pose a major concern to the dairy industry and public health authorities as they are the leading source of listeriosis outbreaks, a severe foodborne infection affecting pregnant women, children, elderly and immunocompromised people, with a high (20–30%) mortality rate. Cheeses offer a suitable environment for the survival and growth of Listeria monocytogenes, allowing this pathogen to display tolerance responses that can favour its presence in cheese and persistence in dairy processing plants. Extensive food safety regulations in the EU towards prevention of contamination of dairy products with L. monocytogenes have been implemented. However due to the specific abilities of this pathogen to overcome the processing hurdles, its control remains a challenge. Compliance with the Good Manufacturing Practices, observation of Hazard Analysis Critical Control Points (HACCP) and the surveillance of the pathogen in the cheese processing environment are crucial to provide consumers with a safe product. This review aims to provide an overview on the current knowledge about the potential for the transmission of L. monocytogenes in cheese and its abilities to overcome the challenging processing conditions and implications for the behaviour of the pathogen in the host.

To examine the antibacterial activity of diverse extracts of propolis harvested at winter and spring from several locations of Algarve, Portugal, against Gram-negative and Gram-positive bacteria was the main goal of the present work. For such, the antibacterial activity was determined by agar diffusion. The results showed that all tested bacterial strains showed susceptibility to diluted propolis extracts and in a dose-dependent manner. Two propolis samples collected at springtime showed higher antibacterial activity, in comparison with samples harvested at wintertime. Ethanolic and methanolic extracts have a very similar activity (P0.05). Helicobacter pylori strains J99 and 26695 were the most susceptible strains to the tested extracts (33.67±2.52 mm and 35.67±0.58mm, respectively). This study constitutes the first approach of the biological activities of Portuguese propolis from the Algarve region and evidences its potential use to combat bacterial infections, in particular against the gastric pathogen H. pylori.

The beneficial effects of honey on human health have long been recognized. Today, many of those positive effects have been studied to elucidate its mode of action. This review briefly summarizes the best studied features of honey, highlighting it as an appealing alternative medicine. In these reports, the health benefits of honey range from antioxidant, immunomodulatory, and anti-inflammatory activity to anticancer action, metabolic and cardiovascular benefits, prebiotic properties, human pathogen control, and antiviral activity. These studies also support that the honey's biological activity is mainly dependent on its floral or geographic origin. In addition, some promising synergies between honey and antibiotics have been found, as well as some antiviral properties that require further investigation. Altogether, these studies show that honey is effectively a nutraceutical foodstuff. info:eu-repo/semantics/publishedVersion

As with most foodborne pathogens, Listeria monocytogenes, during its life cycle, encounters many environmental stresses, beginning with its residence in soil, through the food production chain until it encounters host challenges to accomplish a successful infection process. Exposure to a single stress or a combination of stresses can compromise the integrity of the bacterial cell, and to circumvent those injuries the pathogen is equipped with mechanisms that can sense sublethal stress and trigger its gene expressing arsenal to reprogram its mode of survival by expressing stress tolerance factors. Such tolerance factors were initially identified using laboratory media. However, these approaches did not reliably translate those tolerance responses in real food matrices that the pathogen requires, and the molecular elements associated with those responses. Using different omics approaches, recent studies are revealing the tolerance responses associated with different food matrices and their possible impact in enabling the pathogen to better survive in vivo stress challenges. This knowledge is useful for developing new and more efficient control strategies and improving food safety, especially for minimally processed foods.

In this study the intestinal microbial proteome of children with established type 1 diabetes (T1D) was compared with the proteome of healthy children (Control) with the aim to identify differences in the activity of the intestinal microbiota that will not only contribute to a deeper knowledge of the functionality of the gut in these children but may also provide new approaches to improve the Control of the disease. Fecal protein extracts collected from three T1D children (aged of 9.3 - 0.6) and three Control children (aged of 9.3 - 1.5) were analyzed using a combination of two-dimensional gel electrophoresis (2-DE) and spectral counting. The results evidenced markedly differences between the intestinal proteome of T1D children and the Control. The T1D microbial intestinal proteome was enriched with proteins of clostridial cluster XVa and cluster IV and Bacteroides. In contrast, the Control proteome was enriched with bifidobacterial proteins. In both groups proteins with moonlight function were observed. Human proteins also distinguished the two groups with T1D children depleted in exocrine pancreatic enzymes.

Edible coatings supplemented with essential oil components have been investigated to control spoilage microorganisms. In this study, the survival of Listeria monocytogenes and Salmonella enterica serovar Typhimurium on apples treated with edible coatings based on sodium alginate (2%) (ECs) and supplemented with essential oil components, namely eugenol (Eug) at 0.2% or in combination with 0.1% (v/v) of Eug and citral (Cit) at 0.15% was determined. Both bacterial pathogens were exposed on apples treated with ECs supplemented with Eug or Eug + Cit and challenged with gastrointestinal fluids and their survival was examined. Both pathogens were able to survive on the surface of &lsquo, Bravo de Esmolfe&rsquo, apple. The use of ECs in fresh-cut fruits impaired the survival of both bacterial populations over 72 h at 4 &deg, C. The exposure of the pathogens on apples with ECs supplemented with Eug and Cit and challenged with gastrointestinal fluids significantly reduced their survival. This study evidences that the use of alginate edible coating enriched with Eug or the combination of Eug and Cit can contribute to the safer consumption of minimally processed fruits.

The gastrointestinal system poses different stresses to the foodborne pathogen, Listeria monocytogenes, including the low pH of the stomach and the presence of bile and the high osmolality of the intestinal fluid. The present study evaluated how previous exposure of three L. monocytogenes dairy isolates (C882 and T8, serovar 4b isolates and A9 serovar 1/2a or 3b isolate) to a cheese-simulated medium (pH 5.5 and 3.5% NaCl [w/v], adapted cultures) affected subsequent survival in a simulated gastrointestinal system. Listerial cultures exposed to the cheese-simulated medium at pH 7.0, with no added NaCl, were considered non-adapted. To investigate the main events involved in listerial survival during the gastric and intestinal subsequent challenge, a proteomic approach was used. All L. monocytogenes strains were able to survive the deleterious effects of the gastrointestinal fluids and no significant differences were observed between adapted and non-adapted cells. However the L. monocytogenes strains showed a different protein pattern in response to the gastrointestinal stress. Data indicated that synthesis of stress related proteins is more pronounced in non-adapted cells. Although, a significant number of enzymes involved in glycolysis and energy production were also consistently over-produced by the three strains. These findings provided new insights into the means used by L. monocytogenes to overcome the gastrointestinal system and allow the pathogen to move to the next phase of the infectious process.

Due to the high perishability of raspberry fruit, this work was undertaken to study the effect of alginate and pectin based edible coatings enriched with essential oils components on their storage ability. Four formulations of edible coatings, selected in a previous work, were used: sodium alginate (AL) at 2% + eugenol (Eug) 0.1%, AL 2% + citral (Cit) 0.15%, Pectin (PE) 1% + Eug 0.1% and PE 1% + Cit 0.15% + Eug 0.1%. At 0, 5, 10 and 15 d, samples were taken to perform analysis of colour, firmness, soluble solids content (SSC), weight loss, microbial growth, phenolic compounds (total phenolics, flavonoids, anthocyanins), sugars, organic acids, antioxidant activity (TEAC and ORAC), acetaldehyde, CO2 production and sensory evaluation. Cytotoxicity of the edible coatings was also evaluated on THP-1 and Caco-2 cells. Results of this experiment showed that the edible coatings were not cytotoxic and generally did not significantly affect nutritional quality parameters. They were efficient in controlling microbial food spoilage. Acceptance by consumers of the coated raspberries was good up to 14 d, while control fruit were acceptable only till 7 d. The edible coating that best preserved quality was PE 1% + Cit 0.15% + Eug 0.1%. (C) 2016 Elsevier Ltd. All rights reserved.

Summary Biological properties of Moroccan propolis have been scarcely studied. In the present work, the total phenols and flavonoids from 21 samples of propolis collected in different places of Morocco or 3 supplied in the market were determined, as well as the in vitro capacity for inhibiting the activities of acetylcholinesterase, α-glucosidase, α-amylase, lipoxygenase, tyrosinase, xanthine oxidase and hyaluronidase. The results showed that samples 1 (region Fez-Boulemane, Sefrou city) (IC50 = 0.065, 0.006, 0.020, 0.050, 0.014 mg mL−1) and 23 (marketed) (IC50 = 0.018, 0.002, 0.046, 0.037, 0.008 mg mL−1) had the best in vitro capacity for inhibiting the α-amylase, α-glucosidase, lipoxygenase, tyrosinase and xanthine oxidase activities, respectively. A negative correlation between IC50 values and concentration of phenols, flavones and flavanones was found. These activities corresponded to the generally higher amounts of phenols and flavonoids. In the same region, propolis samples have dissimilar phenol content and enzyme inhibitory activities.

The objective of the present work was to develop strategies for increasing the shelf-life of red raspberries (Rubus idaeus L.), by preventing microorganism growth.Fruits coated with alginate plus lemon essential oil (0.2%) or orange essential oil (0.1%) after 15 days of storage had less red skin than the remaining samples. The less red color verified in these samples was also coincident with the lower concentration of anthocyanins at the end of the experiment as well as the lower capacity for scavenging ABTS free radicals or quenching singlet oxygen. Cyanidin and pelargonidin glucosides were found in raspberries fruits. The edible coatings supplemented with the essential oil of orange either at 0.1% or 0.2% were very efficient for controlling yeast and mold growth after 15 days of storage. To control the development of aerobic mesophilic bacteria the use of essential oil of lemon 0.2% and essential oil of orange 0.1% were the most efficient.The application of the film improved post-harvest quality of raspberry, since the addition of essential oils of citrus films promoted to the inhibitory effect of fungi and bacteria growth after 15 days of storage, without changing quality parameters. © 2016 Society of Chemical Industry.

Agua-mel (honey–water) is a typical honey-based product produced by the Portuguese beekeepers, particularly in southern Portugal. Agua-mel was characterized by mineral content and volatiles contents. Mineral content evaluation was performed based on a random sampling of 14 samples from a total of 16 samples provided by local producers. Mineral content showed that potassium predominated in agua-mel samples (1270–4105 mg/kg). The concentration of aluminium in one sample was tenfold higher (5.8 mg/kg) than in the remaining samples (0.3–0.6 mg/kg). Agua-mel volatiles were isolated by hydrodistillation and analysed by gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS) from a subset of eight samples. Cluster analysis showed two poorly correlated clusters (S corr

The performance of two up-flow anaerobic packed bed systems (UAPB) to treat acid mine drainage (AMD) from the Portuguese mines Sao Domingos and Tinoca was investigated. The response of bacterial populations to influent characteristics was also analysed by temperature gradient gel electrophoresis (TGGE). Effective neutralisation (pH raised from 2.8 to 6.5) and removal of metals (>99%) and sulphate (>72%) were observed independently of the AMD source. TGGE fingerprinting and phylogenetic analysis of 16S rRNA gene revealed that the structure of the bacterial consortia developed in each bioreactor was different. The main bacterial groups involved in the treatment of AMD from Tinoca mine were Desulfovibrio sp., Clostridium sp., Desulfitobacterium sp. and members of Bacteroidales order. These bacterial groups were also present in the community developed in the UAPB fed with AMD from Sao Domingos mine but an unidentified bacterium and bacteria affiliated to Citrobacter and Cronobacter genera were detected only in this last system. The results of present study showed that the AMD source fed to the system was determinant for the establishment of different bacterial populations. Furthermore, the potential of the bioremediation systems for the production of water for irrigation purposes was demonstrated.

Salvia officinalis L. oils were isolated from the plant's commercial dried aerial parts, by hydrodistillation, with different distillation times. The essential oils were analysed by gas chromatography and gas chromatography-mass spectrometry. The antioxidant ability was measured using a free radical scavenging activity assay using 2,2-diphenyl-1-picrylhydrazyl (DPPH), a thiobarbituric acid reactive substances (TBARS) assay, a deoxyribose assay for the scavenging of hydroxyl radical, an assay for site-specific actions and a 5-lipoxygenase assay. Antibacterial activity was determined by the agar diffusion method. 1,8-Cineole, α-pinene and camphor were the dominant components of all the essential oils. The different hydrodistillation times did not affect the oil yield nor the relative amount of the oil components. The time of hydrodistillation influenced the antioxidant activity. With the DPPH method, the oils isolated for 2 and 3 h were stronger free radical scavengers, while with the TBARS method, the highest antioxidant values were obtained in the oils isolated for 30 min, 2 and 3 h. Hydroxyl radical scavenging and lipoxygenase activity assays showed the best results with oils isolated for 1 and 3 h. With the deoxyribose method, sage oils at concentrations

The dynamics of the bacterial populations in an up-flow anaerobic packed bed system (UAPB), applied in acid mine drainage treatment using wine wastes as carbon and nutrients source was elucidated by temperature gradient gel electrophoresis (TGGE) analysis. Moreover, TGGE fingerprints of the bacterial communities developed in a UAPB fed with wine wastes and a UAPB fed with pure ethanol were compared. TGGE fingerprinting and phylogenetic analysis showed that the composition of the community in the UAPB fed with wine wastes remained stable during whole time of operation and its bacterial diversity was higher. The bacterial community of the UAPB fed with wine wastes was composed by bacteria affiliated with Desulfovibrio , Clostridium , Citrobacter and Cronobacter genera and with Bacteroidales order, sp. The dominant community developed in the UAPB fed with ethanol was composed by bacteria affiliated with Desulfovibrio sp. The presence of several bacterial groups in the bioreactor fed with wine wastes suggests a synergistic interaction between the different populations. Syntrophic interaction may be the key factor for the utilization of wine wastes, a complex organic substrate, as carbon and electron source for sulphate reduction.