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Fructooligosaccharides (FOS) are prebiotics of interest to the food industry. These compounds can be produced through the transfructosylation reaction by the enzyme fructofuranosidase. This enzyme is widely produced by fungi in a medium rich in sugar. Therefore, in this work, the main objectives were production, purification, biochemical characterization of a novel fructofuranosidase enzyme by Penicillium citreonigrum URM 4459 and synthesize and evaluate the antibacterial potential of fructooligosaccharides. With respect to sucrose hydrolysis, the optimal pH was 5.5, the apparent Km for purified FFase was 3.8 mM, the molecular mass was 43.0 kDa, estimated by gel filtration on Superdex increase G75 controlled by AKTA Avant 25 and confirmed by 10% SDS-PAGE under denaturing condition. Also, the isoelectric point was 4.9. The fractions obtained with enzymatic activities, both stable at acidic pH and high temperatures, as well as being able to produce FOS. Regarding antibacterial activity, the FOS produced in this study showed better results than commercial FOS and other carbon sources. Thus, this work presents relevant data for the use of P. citreonigum to produce fructofuranosidase and consequently FOS and can be used in the food and pharmaceutical industry.

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Fermented milks are a source of bioactive peptides and may be considered as functional foods. Among these, sheep's milk fermented with kefir has not been widely studied and its most relevant properties need to be more thoroughly characterized. This research study is set out to investigate and evaluate the antioxidant and antimicrobial properties of peptides from fermented sheep's milk in Brazil when produced by using kefir. For this, the chemical and microbiological composition of the sheep's milk before and after the fermentation was evaluated. The changes in the fermented milk and the peptides extracted before the fermentation and in the fermented milk during its shelf life were verified. The antimicrobial and antioxidant activities of the peptides from the fermented milk were evaluated and identified according to the literature. The physicochemical properties and mineral profile of the fermented milk were like those of fresh milk. The peptide extract presented antimicrobial activity and it was detected that 13 of the 46 peptides were able to inhibit the growth of pathogenic microorganisms. A high antioxidant activity was observed in the peptides extracted from fermented milk (3.125 mg/mL) on the 28th day of storage. Two fractions displayed efficient radical scavenging properties by DPPH and ABTS methods. At least 11 peptides distributed in the different fractions were identified by tandem mass spectrometry. This sheep's milk fermented by Brazilian kefir grains, which has antioxidant and antimicrobial activities and probiotic microorganisms, is a good candidate for further investigation as a source for bioactive peptides. The fermentation process was thus a means by which to produce potential bioactive peptides.

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BACKGROUND: Infection following abdominal surgery remains a major factor in morbidity among colorectal cancer (CRC) patients. Probiotic therapy has been suggested to improve the clinical and laboratory outcome of patients undergoing gastrointestinal surgery. The aim of this study was to investigate the efficacy of probiotic lactic acid bacteria in patients with CRC in the pre- and postoperative phases. METHODS: Systematic database searches identified 1,080 related articles. However, only seven articles were selected according to the eligibility criteria for qualitative and quantitative evaluation. RESULTS: Most of the reviewed articles presented satisfactory results related to the prevention of surgical inflammation in patients undergoing resection of CRC when using strains of Lactobacillus genus, predominantly. CONCLUSIONS: Probiotics are suggested to prevent surgical inflammation of CRC, at the same time that the combination of particular microorganisms administered is beneficial to the treatment and surgical recovery.

RESUMO

The therapeutic use of probiotics for supporting the antibiotic action against gastrointestinal disorders is a current trend and emerging applications have gained popularity because of their support for various microbiological activities in digestive processes. Microorganisms isolated from kefir with great probiotic properties, in addition to high resistance to harsh environmental conditions, have been widely researched. Administration of probiotic yeasts offers a number of advantages, when compared to bacteria, because of particular characteristics as their larger cell size. In the present study, 28 strains of Saccharomyces cerevisiae were isolated, after in vitro digestion of kefir-fermented milk, and identified by molecular based approaches. A screening was performed to determine important quality requirements for probiotics including: antagonistic and antioxidant activities, ß-galactosidase synthesis, autoaggregation, surface hydrophobicity and adhesion to epithelial cells. The results showed strains: with antagonistic activity against microbial pathogens such as Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis; able to produce ß-galactosidase; with antioxidant activity levels higher than 90%; with hydrophobicity activity and autoaggregation ability (evaluated by adhesion test, where all the strains presented adhesion to mice ileal epithelial cells). These findings are relevant and the strains are recommended for further in vivo studies as well as for potential therapeutic applications.

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Fish processing residues are rich sources of biomolecules with industrial potential, such as enzymes with collagenolytic properties applied in the pharmaceutical, textile and leather sectors. Here, collagenolytic serine proteases were partially purified from the waste (viscera) of smooth weakfish Cynoscion leiarchus and characterized for the purpose of obtaining a value-added product from fisheries resources. The higher activity of the enzyme (72.5 U mL-1) was verified in optimal temperature and pH of 55oC and 8.0, respectively. The enzyme was stable in wide ranges of temperature (25-60oC) and pH (6.5 to 11.5). The ions Ca2+ and Mg2+ increased the protease activity, whilst Pb2+, Al3+ and Cu2+ had an inhibitory effect, as observed in the presence of Benzamidine and TLCK (inhibitors of serine proteases). Hydrolysis was detected after 48 hours, when the enzyme and bovine collagen type I were incubated together. Thus, digestive viscera of C. leiarchus is suggested as an alternative source of enzymes capable of cleaving type I collagen, with similar biochemical properties to bacterial collagenases commonly employed in industrial processes, reducing costs, adding value to the fisheries product and minimizing the environmental impact caused by its waste.

Resíduos do processamento do pescado são fontes ricas em biomoléculas com potencial industrial, como as enzimas com propriedades colagenolíticas empregadas nos segmentos farmacêuticos, têxteis e de couro. No presente trabalho, serino-proteases colagenolíticas dos resíduos (vísceras) do processamento de pescada-branca, Cynoscion leiarchus, foram parcialmente purificadas e caracterizadas, visando à obtenção de um produto de valor agregado, maximizando o aproveitamento de recursos pesqueiros. A atividade da melhor etapa de extração foi 72,5 U mL- 1 , com temperatura e pH ótimos de 55oC e 8.0, respectivamente. A enzima manteve-se estável em faixas amplas de temperatura (25-60oC) e pH (6,5-11,5). Os íons Ca2+ e Mg2+ aumentaram a atividade proteolítica, ao passo que Pb2+, Al3+ e Cu2+ inibiram essa atividade assim como os inibidores de serino-proteases (Benzamidina e TLCK). A hidrólise foi detectada após 48h de incubação com colágeno bovino tipo I. Assim, sugere-se vísceras digestivas de C. leiarchus como fonte alternativa para o fornecimento de enzimas com capacidade de clivar o colágeno do tipo I e com propriedades bioquímicas semelhantes às colagenases bacterianas já empregadas nas etapas de processamento industrial, como forma de redução de custo, agregação de valor ao produto pesqueiro e contribuindo para minimizar o impacto ambiental deste tipo de resíduo.

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RESUMO

Fish processing residues are rich sources of biomolecules with industrial potential, such as enzymes with collagenolytic properties applied in the pharmaceutical, textile and leather sectors. Here, collagenolytic serine proteases were partially purified from the waste (viscera) of smooth weakfish Cynoscion leiarchus and characterized for the purpose of obtaining a value-added product from fisheries resources. The higher activity of the enzyme (72.5 U mL-1) was verified in optimal temperature and pH of 55oC and 8.0, respectively. The enzyme was stable in wide ranges of temperature (25-60oC) and pH (6.5 to 11.5). The ions Ca2+ and Mg2+ increased the protease activity, whilst Pb2+, Al3+ and Cu2+ had an inhibitory effect, as observed in the presence of Benzamidine and TLCK (inhibitors of serine proteases). Hydrolysis was detected after 48 hours, when the enzyme and bovine collagen type I were incubated together. Thus, digestive viscera of C. leiarchus is suggested as an alternative source of enzymes capable of cleaving type I collagen, with similar biochemical properties to bacterial collagenases commonly employed in industrial processes, reducing costs, adding value to the fisheries product and minimizing the environmental impact caused by its waste.(AU)

Resíduos do processamento do pescado são fontes ricas em biomoléculas com potencial industrial, como as enzimas com propriedades colagenolíticas empregadas nos segmentos farmacêuticos, têxteis e de couro. No presente trabalho, serino-proteases colagenolíticas dos resíduos (vísceras) do processamento de pescada-branca, Cynoscion leiarchus, foram parcialmente purificadas e caracterizadas, visando à obtenção de um produto de valor agregado, maximizando o aproveitamento de recursos pesqueiros. A atividade da melhor etapa de extração foi 72,5 U mL- 1 , com temperatura e pH ótimos de 55oC e 8.0, respectivamente. A enzima manteve-se estável em faixas amplas de temperatura (25-60oC) e pH (6,5-11,5). Os íons Ca2+ e Mg2+ aumentaram a atividade proteolítica, ao passo que Pb2+, Al3+ e Cu2+ inibiram essa atividade assim como os inibidores de serino-proteases (Benzamidina e TLCK). A hidrólise foi detectada após 48h de incubação com colágeno bovino tipo I. Assim, sugere-se vísceras digestivas de C. leiarchus como fonte alternativa para o fornecimento de enzimas com capacidade de clivar o colágeno do tipo I e com propriedades bioquímicas semelhantes às colagenases bacterianas já empregadas nas etapas de processamento industrial, como forma de redução de custo, agregação de valor ao produto pesqueiro e contribuindo para minimizar o impacto ambiental deste tipo de resíduo.(AU)

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Cow raw milk from dairy cooperatives was examined for its microbial composition. Among the isolates identified, 17.6% were yeasts. The most frequent genus was Candida, although members belonging to the genera Brettanomyces, Dekkera, and Geotricum were also identified. Although qualitative and quantitative tests for extracellular proteolytic activity were positive for all the species isolated, Candida buinensis showed the highest response (23.5 U/mg); therefore, it was selected for subsequent investigation. The results of fermentations carried out at variable temperature, pH, and soybean flour concentration, according to a 2(3) full factorial design, demonstrated that this yeast ensured the highest production of extracellular proteases (573 U/mL) when cultivated at 35 degrees C, pH 6.5, and using soybean flour concentrations in the range 0.1-0.5% (w/v). The cell-free supernatants showed the highest activity at 25 degrees C and pH 7.0, and satisfactory stability in the ranges 25-30 degrees C and pH 7-9. The first-order rate constants of protease inactivation in the cell-free supernatants were calculated at different temperatures from semi-log plots of the residual activity versus time and then used in Arrhenius and Eyring plots to estimate the main thermodynamic parameters of thermoinactivation (E* = 40.0 kJ/mol; DeltaH* = 37.3 kJ/mol; DeltaS* = -197.5 J/mol K; DeltaG* = 101 kJ/mol).

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The partial characterization and purification of milk clotting enzyme obtained from the (root latex) of Jacaratia corumbensis O. kuntze was studied, by fractional precipitation with ammonium sulphate and ion exchange chromatography. The ammonium sulphate precipitate showed five fractions (AS1- 0-20 percent; AS2 - 20-40 percent; AS3 - 40-60 percent; AS4 - 60-80 percent; AS5 - 80-100 percent) and among the fractions obtained, the 40-60 percent fraction (AS3) showed the highest milk clotting activity with a purification factor of 1.2 fold in relation to the crude extract. This fraction when applied on Mono Q column yielded two protein peaks (p1 and p2), but p1 pool showed the best milk-clotting activity. The optimal pH for the crude and partially purified extract was 6.5 and 7.0, respectively. The maximum milk-clotting activity was at 55ºC for the both crude and partially purified extracts. The enzyme was inhibited by iodoacetic acid which suggested that this enzyme was a cysteine protease, with molecular weight of 33 kDa.

A enzima coagulante de leite obtida de látex de raiz de Jacaratia corumbensis O. kuntze foi caracterizada parcialmente e purificada, por precipitação fracionária com sulfato de amônio e cromatografia de troca de íon. Foram utilizadas cinco frações de sulfato de amônio (AS1 - 0-20 por cento; AS2 - 20-40 por cento; AS3 - 40-60 por cento; AS4 - 60-80 por cento; AS5 - 80-100 por cento), a fração 40-60 por cento (AS3) mostrou alta atividade coagulante com um fator de purificação de 1,2 vezes em relação ao extrato bruto. Esta fração foi aplicada em coluna Mono Q obtendo dois picos de proteína (p1 e p2), o p1 mostrou melhor atividade coagulante. O pH ótimo para o extrato bruto e parcialmente purificado foi 6,5 e 7,0, respectivamente. A atividade coagulante foi atingida a 55ºC para ambos os extratos, bruto e parcialmente purificado. A enzima foi inibida por ácido iodoacético que sugere que esta enzima é uma cisteína protease, com peso molecular de 33 kDa.

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Two sequential half-fraction designs were applied to studying the alpha-toxin partition produced by Clostridium perfringens type A in aqueous two phase systems (ATPS), as a function of four factors: PEG molar mass and concentration, phosphate concentration and pH. The highest purification factor, yield and partition coefficient results were obtained with PEG 8000 (15%, w/w), phosphate at 20% (w/w) and pH 8.0. This system allows, in a single step, an alpha-toxin purification of 4.6-fold with final activity yield of 230% and partition coefficient of 113.9 in the PEG rich phase.

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Clostridium perfringens, a Gram-positive anaerobic bacterium, is widespread in the environment and commonly found in the intestines of animals, including humans. C. perfringens strains are classified into five toxinotypes (A, B, C, D and E) based on the production of four major toxins (alpha, ß, épsilon, iota). However the toxins (theta, delta, lambda and enterotoxin) are also synthesized by C. perfringens strain. Many attempts to purify the toxins produced by C. perfringens have been proposed. In this review we discuss the purification methods used to isolate toxins from C. perfringens reported in last four decades

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