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Aim This study evaluated the inhibitory effects on mycelial growth and damage on membrane integrity and enzymatic activity caused by Conyza bonariensis essential oil (CBEO) on distinct pathogenic Colletotrichum musae isolates, as well as the preventive and curative effects of coatings with gum Arabic (GA) and CBEO to reduce anthracnose development in banana during room temperature storage. The effects of GA-CBEO coatings on some physicochemical parameters of banana were investigated during room temperature storage. Method and results CBEO (0.4-1 μl ml-1 ) inhibited the mycelial growth of C. musae isolates in laboratory media. The exposure of C. musae conidia to CBEO (0.6 μl ml-1 ) for 3 and 5 days resulted in high percentages of conidia with damaged cytoplasmic membrane and without enzymatic activity. Coatings with GA (0.1 mg ml-1 ) and CBEO (0.4-1 μl ml-1 ) reduced the anthracnose development in banana artificially contaminated with C. musae during storage. In most cases, the disease severity indexes found for GA-CBEO-coated banana were lower than or similar to those for banana treated with commercial fungicide. GA-CBEO-coated banana had reduced alterations in physicochemical parameters during storage, indicating more prolonged storability. Conclusion The application of GA-CBEO coatings is effective to delay the anthracnose development in banana during storage, which should help to reduce the amount of fungicides used to control postharvest diseases in this fruit. Significance and impact of the study This is the first study showing the efficacy of coatings formulated with GA and CBEO to delay the development of anthracnose in banana, as well as to decrease alterations in physicochemical parameters indicative of postharvest quality of this fruit during storage. In a practical point of view, GA-CBEO coatings could be innovative strategies to delay the anthracnose development and postharvest losses in banana.

This study evaluated the effects of flours from four different sweet potato root (SPR) varieties, being two with white peel and two with purple peel, on the composition and metabolic activity of human colonic microbiota in vitro. The capability of these SPR flours (20 g/L) to cause alterations in relative abundance of different bacterial groups found as part of human colonic microbiota, as well as in lactic acid and short-chain fatty acid production was evaluated during 48 hr of an in vitro colonic fermentation. The SPR flours were submitted to a simulated gastrointestinal digestion prior to use in experiments. The four SPR flours increased the relative abundance of Lactobacillus/Enterococcus (range: 0.49-4.48%) and Bifidobacterium (range: 0.32-3.27%) and decreased the relative abundance of Bacteroides/Prevotella (range: 0.29-7.49%), Clostridium histolyticum (range: 0.15-2.08%), and Eubacterium rectale/Clostridium coccoides (range: 0.28-3.86%) during the 48 hr of colonic fermentation. The four SPRF flours had positive prebiotic indexes (> 0.38) after 24 and 48 hr of colonic fermentation, reinforcing the occurrence of selective stimulatory effects on colonic microbiota. An increased metabolic activity of human colonic microbiota was caused by tested SPR flours, which was evidenced by decreased pH (range: 3.20-3.83) and increased lactic acid and short chain fatty acid production during the 48 hr of colonic fermentation. The four examined SPR flours were capable of causing positive alterations in composition and driving the metabolic activity of human colonic microbiota during in vitro colonic fermentation, which should be linked to their prebiotic properties. PRACTICAL APPLICATION: The four examined sweet potato root flours (SPRF) caused beneficial alterations in composition besides of driving the metabolic activity of human colonic microbiota in vitro. These results characterize the examined SPRF as candidates for use as prebiotic ingredients by food industry for formulation of value-added functional foods or dietary supplements.

Made available in DSpace on 2022-04-29T08:36:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-12-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Apoio à Pesquisa do Estado da Paraíba Ministério da Ciência, Tecnologia e Inovação Financiadora de Estudos e Projetos Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) The effects of digested microalgae biomass of Chlorella vulgaris, Desmodesmus maximus, Chlorococcum sp. cf hypnosporum, and Spirulina platensis or fructooligosaccharides on human colonic microbiota during in vitro fermentation (48 h) were evaluated. Fructooligosaccharides and digested microalgae biomass increased Lactobacillus-Enterococcus and Bifidobacterium relative abundances and decreased Prevotellaceae-Bacteroidaceae, Clostridium histolyticum, and Eubacterium rectale-Clostridium coccoides. The digested microalgae biomass s showed a higher prebiotic index than fructooligosaccharides, evidenced through the higher selective stimulation of beneficial microorganisms and inhibition of undesirable bacteria on colonic microbiota. S. platensis biomass contained nystose, raffinose, and phenolics, increased the relative abundance of Lactobacillus-Enterococcus and Bifidobacterium, and decreased Eubacterium rectale-Clostridium coccoides, Clostridium histolyticum, and Prevotellaceae-Bacteroidaceae. After 24 h of incubation, the medium fermented with S. platensis promoted an increase in the concentration of acetic and propionic acids. D. maximus biomass showed higher insoluble fibers and kestose, the greatest Lactobacillus-Enterococcus relative abundance, and increases in the butyric and propionic acids after 48 h. C. vulgaris biomass showed the highest glucose and fructose concentrations, some phenolics, and the highest Bifidobacterium relative abundance after 48 h. Laboratory of Microbial Processes in Foods Department of Food Engineering Center of Technology Federal University of Paraíba Laboratory of Food Microbiology Department of Nutrition Health Science Center Federal University of Paraíba Laboratory of Reef Environments and Biotechnology with Microalgae - Exact and Natural Sciences Center Federal University of Paraíba Department of Food Technology Federal Institute of Sertão de Pernambuco Department of Food and Nutrition School of Pharmaceutical Sciences São Paulo State University Federal Institute of Paraná Campus Paranavaí Department of Food and Nutrition School of Pharmaceutical Sciences São Paulo State University Financiadora de Estudos e Projetos: 255709 CNPq: 303437/2017-0 CNPq: 405644/2018-3

Many outbreaks involving Salmonella enterica in dehydrated coconut have been reported. Little is known about the survival of S. enterica in dehydrated coconut flakes at common retail or domestic storage conditions. This study evaluated the behavior of a S. enterica cocktail (S. Enteritidis PT4, S. Typhimurium PT4, S. Bredeney, S. Muenster and S. Agona) in conventionally and osmotically dehydrated coconut flakes under four storage regimes: 25 °C for 120 days, 25 °C for 30 days then 7 °C for 90 days, 7 °C for 30 days then 25 °C for 90 days, and 7 °C for 120 days. S. enterica membrane integrity (using with propidium iodide and bis-1,3-dibutylbarbutyric acid) and metabolic activity (using 5-cyano-2,3-ditolyl tetrazolium chloride) were assessed by flow cytometry analysis after dehydration and storage at 7 °C or 25 °C for 120 days. Lower S. enterica inactivation rates (k

Background and aim High-fat (HF) diet consumption has been associated with gut dysbiosis and increased risk of dyslipidemia, type 2 diabetes mellitus and hypertension. Probiotic administration has been suggested as a safe therapeutic strategy for the treatment of cardiometabolic disorders. This study was designed to assess the effects of probiotic Lactobacillus (L.) fermentum 296, a fruit-derived bacteria strain, against cardiometabolic disorders induced by HF diet. Methods and results Male Wistar rats were divided into control diet (CTL); HF diet; and HF diet treated with Lactobacillus fermentum 296 (HF + Lf 296). The L. fermentum 296 strain at 1 × 109 colony forming units (CFU)/ml were daily administered by oral gavage for 4 weeks. The results showed that rats fed with HF diet displayed insulin resistance, reduced Lactobacillus spp. counts in feces, serum lipids, and oxidative profile. Rats fed on HF diet also demonstrated augmented blood pressure associated with sympathetic hyperactivity and impaired baroreflex control. The administration of L. fermentum 296 for 4 weeks recovered fecal Lactobacillus sp. counts and alleviated hyperlipidemia, sympathetic hyperactivity, and reduced systolic blood pressure in HF rats without affecting baroreflex sensibility. Conclusion Our results suggest the ability of L. fermentum 296 improve biochemical and cardiovascular parameters altered in cardiometabolic disorders.

Background Sweet potato (SP) roots play an old and important role in food culture worldwide, although only in recent years this food has been research focus as a source of bioactive compounds. Scope and approach This review provides an update and discusses available literature concerning bioactive compounds naturally present in SP roots and their potential beneficial effects on human health. Available literature reveals that, in addition to the valuable nutritional composition, SP roots contain a variety of constituents capable of promoting health and preventing lifestyle-related diseases. Functionalities of polyphenols, carotenoids, polysaccharides, dietary fiber and proteins/peptides commonly found in SP roots have been confirmed in in vitro and in vivo investigations, which include: antioxidant, prebiotic, anti-hypertensive and anti-proliferative effects. Several SP varieties can be found, including purple, orange, white and yellow-fleshed SP, which differ in amounts of nutrients and bioactive compounds, and, consequently, in their ability to exert beneficial effects to consumers. Key findings and conclusions SP roots should be considered a healthy food option for use in different domestic meal preparations as well as for use by food industry as a functional ingredient for formulation of added-value food products.

Microencapsulation process can affect negatively the viability of microencapsulated cells in different extent. Flow cytometry (FC) is a technique receiving increasing attention in last years as a method to measure viability of bacterial cells. Principle of FC relies on fact that each cell passes a point within the flow path, being intercepted by a laser, which scatters light in two major directions known as forward angle light scatter or side angle light scatter. Cell detection and enumeration involves collection of fluorescence signals emitted at distinct wavelengths from labeled/stained cells as they pass lasers. Data is collected from individual stained cells, and degree of uptake of a particular stain allows differentiation of cells into discrete subpopulations. FC data can reflect distinct physiological conditions and viability of bacterial cells. Therefore, a combination of dyes, such as propidium iodide and thiazole orange, has been successfully used to assess viability in bacterial cells.

This study assessed the survival of the fruit-derived and freeze-dried L. plantarum 49, L. brevis 59, L. paracasei 108, L. fermentum 111 and L. pentosus 129 strains during frozen storage and when incorporated into apple, orange, and grape juice stored under refrigeration. Physicochemical parameters of juices containing the freeze-dried Lactobacillus strains and the survival of the test strains in the fruit juices during in vitro digestion were also evaluated.; Results: No decreases in survival rates (log N/log N0) of the freeze-dried cells were observed in up to 1 month of storage. The survival rates of the freeze-dried strains L. plantarum 49 and L. paracasei 108 were > 0.75 in up to 4 months of storage. All freeze-dried strains exhibited survival rates of >0.75 in up to 2 weeks of storage in apple juice; only L. plantarum 49 and L. paracasei 108 showed similar survival rates in orange and grape juices in up to 2 weeks of storage. The contents of the monitored organic acids or sugars during storage varied depending on the added strain and the type of fruit juice. At the end of in vitro digestion, L. brevis 59, L. paracasei 108 and L. fermentum 111 showed survival rates of >0.80 in apple juice.; Conclusion: Apple juice was the best substrate for the survival of the tested freeze-dried Lactobacillus strains over time. L. paracasei 108 and L. plantarum 49 were the strains presenting the best performance for incorporation in potentially probiotic fruit juices. © 2018 Society of Chemical Industry.; © 2018 Society of Chemical Industry.

Nine wild Lactobacillus strains, namely Lactobacillus plantarum 53, Lactobacillus fermentum 56, L. fermentum 60, Lactobacillus paracasei 106, L. fermentum 250, L. fermentum 263, L. fermentum 139, L. fermentum 141, and L. fermentum 296, isolated from fruit processing by-products were evaluated in vitro for a series of safety, physiological functionality, and technological properties that could enable their use as probiotics. Considering the safety aspects, the resistance to antibiotics varied among the examined strains, and none of the strains presented hemolytic and mucinolytic activity. Regarding the physiological functionality properties, none of the strains were able to deconjugate bile salts; all of them presented low to moderate cell hydrophobicity and were able to autoaggregate, coaggregate with Listeria monocytogenes and Escherichia coli, and antagonize pathogenic bacteria. Exposure to pH 2 sharply decreased the survival of the examined strains after 1- or 2-h exposure; variable decreases were noted after 3-h exposure to pH 3. Overall, exposure to pH 5 and to bile salts (0.15, 0.3, and 1%) did not decrease the strains' survival. Examined strains presented better ability to survive from the exposure to simulated gastrointestinal conditions in laboratorial media and milk than in grape juice. Considering the technological properties, all the strains were positive for proteolytic activity and EPS and diacetyl production, and most of them had good tolerance to 1-4% NaCl. These results indicate that wild Lactobacillus strains isolated from fruit processing by-products could present performance compatible with probiotic properties and technological features that enable the development of probiotic foods with distinct characteristics.

The ability of probiotics to exert benefits on host has been associated with different physiological functionalities in these microorganisms, namely cell surface hydrophobicity, autoaggregation, coaggregation with pathogens, antagonistic activity against pathogens and ability to survive the exposure to gastrointestinal conditions. This study assessed the effects of different concentrations of quercetin (QUE) and resveratrol (RES) on the ability of six potentially probiotic Lactobacillus strains to tolerate different pH values and bile salt concentrations, to autoaggregate, coaggregate with and antagonize pathogens and survive the exposure to simulated gastrointestinal conditions. QUE and RES presented low inhibitory effects on all tested Lactobacillus strains, with minimum inhibitory concentration (MIC) ranging from 512 to >1024 μg/mL. In most cases, QUE and RES at all tested concentrations (i.e., MIC, 1/2 MIC, and 1/4 MIC) did not affect the tolerance of the Lactobacillus strains to acidic pH and bile salts. QUE increased cell surface hydrophobicity of most of the tested Lactobacillus strains and increases or decreases in cell surface hydrophobicity varied in the presence of different RES concentrations among some strains. QUE and RES increased the ability of tested Lactobacillus strains to autoaggregate and coaggregate with pathogens. QUE and RES did not negatively affect the antagonistic activity of the tested Lactobacillus strains against pathogens and did not decrease their survival rates when exposed to in vitro gastrointestinal conditions. In a few cases, the ability of some tested Lactobacillus strains to antagonize pathogens, as well as to survive specific steps of the in vitro digestion was increased by QUE and RES. QUE exerted overall better protective effects on the measured in vitro properties of tested Lactobacillus strains than RES, and L. fermentum and L. plantarum strains presented better responses when treated with QUE or RES. These results showed that probiotic Lactobacillus strains could present low susceptibility to QUE and RES. Combined use of QUE and RES with probiotic Lactobacillus could improve their functionalities on the host; however, the concentration of these polyphenols should be carefully selected to achieve the desirable effects and vary according to the selected probiotic strain.

This study evaluated whether jabuticaba by-product (JB) can exert prebiotic effects through the measurements of its stimulatory effects on growth and metabolism of probiotic L. acidophilus, L. casei and Bifidobacterium animalis subsp. lactis. Freeze-dried JB had high contents of dietary fiber, particularly of soluble fiber, and presence of sugars and a variety of phenolics. Freeze-dried JB was submitted to a simulated gastrointestinal digestion before use in assays. Digested JB showed positive prebiotic activity scores on examined probiotics. After a 48 h-cultivation in medium with digested JB (20 g/L), probiotics had counts >8 log CFU/mL, which were similar to those found in medium with fructooligosaccharides. Cultivation of probiotics in medium with digested JB resulted in decreased pH, increased production of lactic acid and short-chain fatty acids (i.e., acetic, butyric and propionic) and consumption of glucose and fructose over time, indicating intense metabolic activities. Probiotics had variable ability to metabolize specific phenolics of digested JB during cultivation. JB has potential prebiotic properties, which could be exploited in formulations of added-value food products.

The chemical composition and potential prebiotic effects of 4 different flours from varieties of sweet potato roots (SPR), including two with white peel and two with purple peel, cultivated in Northeastern Brazil were studied. SPR flours (SPRF) showed variable contents of soluble (1.8–3.0%) and insoluble (4.6–5.8%) fiber, resistant starch (6.2–10.3%), nystose (not found up to 7.1 g/l), kestose (1.7–5.4 g/l), phenolic compounds (phenolic acids: not found up to 16.9 mg/l, flavanols: not found up to 20.4 mg/l, flavanones: not found up to 26.0 mg/l) and sugars (fructose: 4.6–6.1 g/l, glucose: 5.4–8.7 g/l, maltose: 3.2–27.2 g/l). SPRF (20 g/l) with and without a simulated gastrointestinal digestion had an average positive prebiotic activity score (0.11–0.55) with probiotics Lactobacillus acidophilus, L. casei and Bifidobacterium animalis to the detriment of enteric competitors, showing selective stimulatory effects on beneficial bacteria species that are found as part of the gut microbiota. Cultivation of these probiotics in media with or without simulated digestion (SPRF, 20 g/l) showed high bacterial counts (8.2–9.7 log CFU/ml), decreased pH, increased acetic, formic, lactic, malic, succinic and tartaric acids and decreased fructose, glucose and maltose over time, which are indicative of strong metabolic activity. These results showed that flours from different SPR varieties are potential prebiotic ingredients for use in the formulation of functional foods or dietary supplements.