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RESUMO Alimentos intensamente manipulados, como as lingüiças mistas do tipo frescal são freqüentemente responsáveis pela veiculação de enfermidades transmitidas por alimentos. Devido ao risco à saúde pública que a bactéria

In previous studies, it has not been reported that protein isolated from chia interferes favorably with antibacterial activity, and reduces cholesterol synthesis. The objective of this study was to determine whether commonly used commercial microbial proteases can be utilized to generate chia protein-based antibacterial and hypocholesterolemic hydrolysates/peptides, considering the effects of protein extraction method. Alcalase, Flavourzyme and sequential Alcalase-Flavourzyme were used to produce hydrolysates from chia protein (CF), protein-rich fraction (PRF) and chia protein concentrates (CPC1 and CPC2). These hydrolysates were evaluated for their antimicrobial activity against Gram-positive (G) and Gram-negative (G) microorganisms. The protein hydrolysates were purified by ultrafiltration through a membrane with 3 kDa nominal molecular weight, for evaluation of hypocholesterolemic activity. An inhibition zone was observed when the hydrolysate was tested against S. aureus, and minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values were obtained. Peptides from chia protein with molecular mass lower than 3 kDa reduced up to 80.7% of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) enzymatic reaction velocity. It was also observed that, independent of the method used to obtain chia proteins, the fractions showed relevant bioactivity. Moreover, the intensity of the bioactivity varied with the method for obtaining the protein and with the enzyme used in the hydrolysis process. This is the first report to demonstrate that chia peptides are able to inhibit cholesterol homeostasis.

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Sixty-five strains of coagulase positive staphylococci (Staphylococcus aureus, S. intermedius and S. hyicus) were identified at species level by PCR amplification of the coa gene, specific for S. aureus, and of the nuc gene, specific for S. intermedius and for S. hyicus.

Fruits are widely consumed and play a crucial role in diet. Furthermore, changes in dietary habits and growing world population have promoted the increase in demand of this product, which consequently increase their wastes. Besides, the fruit processing, including juice processing, pulp extraction, jams, and frozen pulp, also generates significant amounts of waste. Wastes include skin, pulp, seed waste, and pomace, which are rich in value‐added compounds like starch. The search for new starch sources has been motivated by three main reasons: growing market demand; industry demand for new starches with different physicochemical, structural, and functional properties than conventional starch sources; and food supply to meet the increase of world population. The principal conventional sources of starch are cereal and tubers. However, fruit wastes can contain significant amounts of starch that can be better explored. Fruit waste starches have unique features and can expand the possible range of starch uses in industry. This review explores fruit wastes, including kiwifruit, pineapple, mango, litchi, tamarind, longan, loquat, annatto, jackfruit, avocado, apple, and banana as new sources of starch, and also discusses their extraction methods, properties, and potential uses.

RESUMO.A partir da década de 80, as técnicas moleculares começaram a ser utilizadas como uma alternativa aos métodos fenotípicos, tradicionalmente, utilizados em microbiologia de alimentos. Foi acelerada esta substituição com advento da descoberta da reação em cadeia da polimerase (polymerase chain reaction -PCR). Este artigo tem por objetivo revisar as principais técnicas moleculares utilizadas como ferramentas na microbiologia de alimentos, desde as, inicialmente, desenvolvidas, como a análise do perfil plasmidial, até as mais contemporâneas como o PCR em tempo real, discutindo as características, vantagens e desvantagens destas técnicas, avaliando a potencialidade destas para suprir as limitações das técnicas tradicionais.Palavras-chave: REA, PFGE, ribotipagem, RAPD, RT-PCR, multiplex PCR.ABSTRACT. Molecular techniques applied to food microbiology. Beginning in the 1980s, molecular techniques became an alternative to the traditionally used phenotypic methods in food microbiology. With the advent of the polymerase chain reaction technique, this substitution was speed up. This article had as objective to review the main molecular techniques used as tools in food microbiology, from plasmidial profile analysis to contemporary techniques such as the real-time PCR. The characteristics, advantages and disadvantages of these techniques are discussed, by evaluating the potential of these techniques to overcome the limitations of traditional techniques.

Pleurotus species are found to be among the most efficient lignocellulolytic types of white-rot fungi. Rice is the main grain cultivated in the extreme south of Brazil. Defatted rice bran and straw are by-products of low aggregate value. Soft rush (Juncus effusus) is a common native plant also very abundant in the region. In the present work, we evaluated changes in substrate composition after growth of two white-rot fungal species: Pleurotus ostreatus and Pleurotus sajor-caju, aiming to increase protein content and digestibility from substrates through solid fermentations and obtain edible mushrooms of high aggregate value. For that, defatted rice bran, defatted rice straw and soft rush were utilized as substrate. The influence of the variables thermal treatment temperature of substrate, substrate moisture and concentration were evaluated on the protein content, digestibility and biological efficiency. The highest protein enrichment of rice bran in P. sajor-cajufermented medium was due the fact that there was no fructification in these media, while for the P. ostreatusfermented medium, part of the synthesized protein was converted into mushrooms. The highest protein enrichments were verified in medium with 80% moisture and 25% soft rush (47.1% using P. ostreatus and 49.0% using P. sajor-caju). A higher digestible protein increase was obtained for both species in media with 70% moisture and 25% soft rush.