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Consumption of dairy products is one of the most natural ways to introduce probiotics. However, the beneficial effects of the probiotics might depend on the administration form. The aim of this study was to investigate the beneficial properties of two probiotic strains: Bifidobacterium animalis subsp. lactis (BB-12) and Lactobacillus acidophilus (LA-5) in different administration forms (capsules and yogurt). First, in vitro resistance to gastrointestinal condition, surface properties, and immunomodulation capacities were determined. Then, the anti-inflammatory properties of the probiotic strains administrated on yogurt or capsules were tested in a dinitrobenzene sulfonic acid (DNBS)-induced colitis mouse model. The survival rates of BB-12 and LA-5 strains to gastrointestinal conditions were slightly higher when yogurt was used as carrier. They showed most affinity to hexane (no-polar basic solvent) than ethyl-acetate (polar basic solvent). BB-12 showed the higher binding capacity to HT-29, Caco-2, and mucin. Both probiotic candidates suppress the secretion of IL-8 secretion by HT-29-TNF-α stimulated cells. Finally, administration of BB-12 and LA-5 strains improve colitis in mice. They protect against weight loss, inflammation, and hyperpermeability induced by DNBS. However, these anti-inflammatory effects were limited when mice were treated with the probiotic strain on a yogurt matrix. Overall results indicate that BB-12 and LA-5 positive properties are compromised depending on the matrix. Consequently, the selection of an appropriate matrix is an important criterion to conserve the positive benefits of these probiotic strains.

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BACKGROUND: Sprouting is known to improve cereal and pulse nutritional properties. However, several outbreaks of illness have been reported after raw sprout consumption. This research aimed to improve wheat sprout hygienic properties through the use of zinc diacetate. Sprouting conditions (sprouting temperature, soaking time and zinc diacetate solution concentration) were optimized to decrease total plate count, coliforms, and molds and yeasts using a factorial design approach and a desirability function. RESULTS: Based on the responses, the effects of variables were calculated and the interactions between them were determined. Optimal conditions were defined as follows: sprouting temperature 18 °C, soaking time 0.66 h and zinc diacetate concentration 400 mg L-1 . These conditions led to the elimination of coliforms and a decrease in total flora count by 2 log. Interestingly, zinc sprouting increased the zinc content of sprouts and improved their nutritional properties. CONCLUSION: Results showed that the use of zinc solution is a useful tool to improve sprout hygienic and nutritional properties. © 2019 Society of Chemical Industry.

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Acacia honey, as a favored delicacy, was supplemented with extracts of distinctive Ganoderma lucidum (lingzhi or reishi) variants to enhance its biological value and lay the foundations for prospective functional food application. Health promoting effects of G. lucidum have already been documented and its prebiotic features have been verified. In spite of promising studies and its unambiguous nutritional value, G. lucidum mushroom has not gained extensive use in the food industry so far. Special honey-based foodstuffs fortified with G. lucidum extract were developed as novel food prototypes, and screened for their enhanced total phenolic content (TPC), antioxidant (FRAP), and antiradical activity (DPPH). The obtained variants were also investigated for the possibly increased prebiotic index by means of an in vitro digestion procedure. A concentration dependent positive correlation was observed for all the studied parameters in case of the investigated prototypes. Supplementation of acacia honey with 0.5% reishi mushroom extract significantly increased the TPC, the antioxidant activity, and the radical scavenging power. A statistically significant improvement in the prebiotic index was also observed for the developed prototypes when compared with pure acacia honey. The evidence gained from the conducted studies fully supports the conception of combining honey and reishi extract to obtain a functional food product of high biological potential.

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BACKGROUND: Lactobacillus and Bifidobacterium strains are present in a great variety of habitats, including fermented products, probiotic concoctions and the human colon. Some species are so closely related that it is difficult to distinguish them by microbiological techniques. Nevertheless, discrimination of isolates is an important issue in respect of application, and molecular methods such as restriction fragment length polymorphism (RFLP), random amplification of polymorphic DNA (RAPD) or species-specific polymerase chain reaction (PCR) might help in resolving this problem. In this study, PCR, RFLP and sequencing were applied to identify lactobacilli and bifidobacteria originating from various sources and the DSMZ strain collection. RESULTS: The microbiological composition of foods was analysed by molecular methods. Using species-specific PCR primers, three restriction enzymes (AluI, HhaI and RsaI) and sequencing, three Bifidobacterium and six Lactobacillus reference strains could be distinguished and four additional lactobacilli of food origin were identified. CONCLUSION: A combination of three molecular methods resulted in successful discrimination of nine reference strains and four isolates of food origin. Since these methods are not always accurate owing to their high genetic homogeneity, it is advisable to use more than one method for the identification of L. casei and closely related species.

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The growth response of 25 Trichoderma strains to 26 alkanols and 7 other organic solvents was examined in vitro. The sensitivity of strains considerably varied depending on their taxonomic position, thus the strains of Longibrachiatum section proved to be more tolerant than those of Pachybasium and Trichoderma sections. Significant relationship was revealed between structure of C1 -C24 alkanols and their growth inhibitory effect to Trichodermas, both efficacy and selectivity of C1 -C3 and C14 -C24 alkanols failed off the C9 -C11 alkanols. The non-alkanol solvents tested were non-toxic. The C8 -C11 alkanols used in agricultural practices exhibited noticeable toxicity to all Trichoderma strains, therefore pesticidal preparations containing these alkanols cannot be used simultaneously with Trichoderma based biopreparations.

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Our study aimed at acquiring information about the biological effect of pesticides and their degradates produced by UV-treatment on microbiological activity. Five photosensitive pesticides (carbendazim, acetochlor, simazine, chlorpyrifos, EPTC) and six representative soil microbes (Bacillus subtilis, Pseudomonas fluorescens, Mycobacterium phlei, Fusarium oxysporum, Penicillium expansum, Trichoderma harzianum) were applied throughout our model experiments. The antimicrobial effects of the pesticides and their degradates were assessed with filter paper disk method. The antimicrobial effect of the degradation products exhibited marked differences in terms of pesticide types, irradiation time, and the test organisms. Acetochlor and its photolytic degradation products were found to be more toxic to bacteria than fungi. All the three bacteria proved to be sensitive to the basic compound and its degradation products as well. The end product of carbendazim was weakly antibacterial against P. fluorescens and B. subtilis but strongly antifungal against T. harzianum. Chlorpyrifos and its end product inhibited neither test organisms, but the degradates hindered the growth of four of them. The basic compound of EPTC and the degradates of simazine exhibited significant toxicity to the test bacteria. It might be claimed that the pesticide photodegradation may result in significant changes in soil microbiota, as well as formation of biologically harmful degradates.

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The measuring station of the 10 MW VVR-SM research reactor at the Budapest Neutron Centre (Hungary) was used to perform dynamic neutron radiography (DNR), which was, to our best knowledge, the first time, in a Tortella tortuosa biotope. In the conducted study, two trophical levels, moss and spider Thomisidae sp. juv., were examined. Cadmium penetration routes, distribution and accumulation zones were visualized in the leafy gametophyte life cycle of Tortella tortuosa and in the organs of the spider.

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