-Pollen is the main protein source for honey bees, and its quality and digestibility are important factors for bee health. We compared the effects of eight different mixed-pollen diets on queenless adult survival and physiology. The mixtures represented the pollen source for bees in a natural environment. They consisted of three to five familial pollen types, and the protein percentage varied from 8.4 to 18.1 %. The mixtures that contained mainly Asteraceae pollen were less consumed and enhanced bee mortality, suggesting that this pollen type offers poor nutritional quality and assimilation for the bees. All pollen diets promoted ovarian activation, but among the pollentreated groups, the percentage of bees with activated ovaries was not related to the protein content of the diet, which suggests that ovarian activation may also depend on other nutrients. Survival was also positively correlated to the vitellogenin levels in the hemolymph. Our results showed that the amount of protein consumption and the pollen type influenced bee survival and physiology.polyfloral pollen diet / ovary / hemolymph proteins / survival

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Staphylococcus aureus is one of the main causative agents of food poisoning. This bacterium is an important component of cheese microbiota and plays an important role in foodborne diseases. Another important component of the microbiota is the lactic acid bacterium, which actively participates in processes that define the physicochemical, sensorial, and microbiological features of cheese. Of the various microbiological interactions in cheese, the interaction between lactic acid bacteria and Staph. aureus is most relevant. To this end, we evaluated the viability of Staph. aureus strains and the expression of their enterotoxins in cheeses produced experimentally, using Weissella paramesenteroides GIR16L4 or Lactobacillus rhamnosus D1 or both as starter cultures. Over 7 d, we observed that the presence of lactic acid bacteria did not impair Staph. aureus growth. However, via qPCR we observed a change in the gene expression of staphylococcal enterotoxins, suggesting that molecular communication exists between Staph. aureus strains and lactic acid bacteria in cheese.

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The consumption of raw milk and its products is a risk factor associated with zoonotic tuberculosis. Lactic acid bacteria (LAB) show inhibitory activity against Mycobacterium bovis, the causative agent of tuberculosis. The aim of this study was to assess the in vitro antagonistic activity of LAB from Brazilian Minas artisanal cheese against M. bovis bacillus Calmette-Gu erin (BCG). Nine LAB were tested against M. bovis BCG in five in vitro antagonistic assays. Four lactobacilli gave the best results in all the experiments. This could be due to their growth rate, acid and bacteriocin production. In conclusion, LAB are capable of inhibiting M. bovis BCG viability.

The slow process to obtain fruit vinegar is based on low speed of acetylation, with good reproducibility in the laboratory and low expense. This study aimed to produce a mango vinegar by the method of slow acetylation or Orleans method. The acetic fermentation was carried with mango fermented with an alcohol content of 7% (v. v -1) and added 100 ml of strong vinegar unpasteurized as inoculum. The fermentation occurred for 28 days, samples were removed every seven days (0, 7, 14, 21 e 28). Vinegar presented volatile acid content of 3.23 ± 0.07 %, total acidity (4.21 ± 0.11 %), pH (3.28 ± 0.03), residual ethanol (0.95 ± 0.01 %), carotenoids (12.67 ± 1.14 mg. 100mL-1) and total phenolic compounds (31.80 ± 2.00 mg catechin. 100mL-1). The acid conversion was 0.799 ± 0.01 g. g-1 and the yield Gesammte Konzentration (GK) of 64.00 ± 5.04 %. The vinegar obtained showed significant levels of total carotenoids and phenolics. It was possible to obtain sleeve vinegar by slow acetylation process, however it is necessary the development of studies regarding acetylation method in order to increase the productivity and efficiency of the process as well as to minimize evaporative losses, decrease the chances of contamination and to increase the acetic acid content in obtaining vinegar according to recommended in the current Brazilian legislation.

Currently, the search for natural antimicrobial agents has increased. Thereat, plant extracts, products of fermentative processes, and microbial growth have been tested. Kombucha is a fermented beverage that resulted from the fermentation of the infusion of Camellia sinensis. There are reports about biological activities, such as anti-inflammatory, digestibility, antioxidant, antimicrobial, and others. The study aimed to evaluate the antibacterial activity of black and green tea kombucha against eight foodborne pathogenic microorganisms. The antibacterial activity was analyzed using the agar well diffusion method. Each kombucha consisted of three treatments: natural, neutralized, and filtered. The solutions of acetic acid (4% v.v-1) and kanamycin (30 µg.L-1) were used as a control. The black and green tea kombucha beverages, not neutralized, showed antibacterial activity against Escherichia coli serotypes. Black and green tea kombucha did not show antibacterial activity against Staphylococcus aureus, Shigella Flexneri, and Salmonella Typhimurium. The inhibition may be attributed to acetic acid production during the fermentation process. Therefore, it appears that kombucha may have a potential antimicrobial agent. Keywords: Camellia sinensis, fermentation, antimicrobial.

Bebidas fermentadas de frutas são uma alternativa viável e de baixo custo para o aproveitamento dos frutos. Objetivou-se produzir e caracterizar um fermentado alcoólico de manga utilizando células de Saccharomyces cerevisiae isoladas de fermento comercial. A matéria-prima e o processo fermentativo foram caracterizados e o fermentado de manga produzido apresentou: teor alcoólico (7,61 ± 0,13 g.L-1), açúcares residuais (1,24 ± 0,04 g.L-1), pH (3,73 ± 0,05), acidez total (83,34 ± 6,65 mEq.L-1), extrato seco (96,75 ± 1,72 g.L-1), produtividade em etanol (0,23 ± 0,02 g.L-1. h-1), eficiência da fermentação (91,50%), conversão de produto em substrato -Y p/s (0,470 g. g-1) e rendimento em etanol de 85%. Os teores de carotenoides e fenólicos totais foram de 17,33 ± 1,97 mg.100mL-1 e 24,60 ± 0,10 mg de catequina.mL-1, respectivamente. É possível produzir uma bebida alcoólica fermentada de manga de boa qualidade e dentro dos parâmetros físico-químicos exigidos pela legislação a partir da levedura S. cerevisiae proveniente de fermento comercial.