RESUMO
Corn bran is a byproduct produced from corn milling; it is rich in ferulic acid and hemicellulose. In this research, the effects of feruloylated oligosaccharides (FOs) from maize bran on the microbial diversity and profiles in rat feces were investigated through 16S rRNA sequencing. FOs significantly increased bacterial richness and diversity compared with the control and xylooligosaccharides (XOS) alone. In comparison with the control group and the group administrated with XOS, FOs orally administered at 300 mg/kg increased OTU in feces by 57.0 and 24.8 %, and Chao value by 93.4 and 37.6 %, respectively. FOs also influenced obesity- and diabetes-associated bacteria. Oral administration of FOs at 300 mg/kg decreased the ratio of Firmicutes to Bacteroidetes from 477.7:1 to 55.1:1; greatly increased the reads of bacteria that were previously found resistant against diabetes in rats, such as Actinobacteria, Bacteroides, and Lactobacillus; whereas decreased diabetes-prone bacteria, such as Clostridium and Firmicutes.
Assuntos
Bactérias/efeitos dos fármacos , Fibras na Dieta/administração & dosagem , Microbioma Gastrointestinal/efeitos dos fármacos , Oligossacarídeos/administração & dosagem , Zea mays/química , Administração Oral , Animais , Bactérias/genética , Bacteroidetes/efeitos dos fármacos , Bacteroidetes/genética , Ácidos Cumáricos/metabolismo , Fezes/microbiologia , Firmicutes/efeitos dos fármacos , Firmicutes/genética , Microbioma Gastrointestinal/genética , Glucuronatos/administração & dosagem , Lignina/química , Masculino , Oligossacarídeos/metabolismo , Polissacarídeos/metabolismo , RNA Ribossômico 16S/genética , RatosRESUMO
Hydrogel composites based on pineapple peel carboxymethyl cellulose, polyvinyl alcohol and mesoporous silica SBA-15 were synthesized by an eco-friendly method of repeated freeze-thaw cycles for the application of papain immobilization. The experiment was optimized to obtain an efficient papain immobilization carrier. Simultaneously the immobilization conditions, including enzyme concentration, pH, crosslinker concentration and cross-linking time were optimized. The immobilized papain had maximum activity at low reaction temperature of 40°C and showed pH-sensitivity by exhibiting a rapid decrease of activity within a narrow range from pH 7.0 to pH 7.5. Compared with the free papain, the immobilized papain revealed enhanced pH, thermal and storage stability. After 2h incubation at 80°C, the immobilized papain retained 56% of its initial activity while the free papain only retained 16%. After 10days of storage, 79% of the initial activity was retained for the immobilized papain while only 27% for the free papain.
Assuntos
Ananas/química , Carboximetilcelulose Sódica/química , Enzimas Imobilizadas/química , Hidrogéis/química , Papaína/química , Reagentes de Ligações Cruzadas , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Álcool de Polivinil , Dióxido de Silício , TemperaturaRESUMO
In the present study, digestion under saliva, simulated gastric and small intestinal conditions and fermentation in vitro of polysaccharides from the flowers of Camellia sinensis (TFPS) by human gut microbiota were investigated. The results indicated that human saliva and simulated gastric and intestinal juices had no effect on TFPS, while TFPS could be utilized by human fecal microbiota, which was proved from the decreased molecular weight and lower content of total or reducing sugars after fermentation under anaerobic conditions. It was found that pH in the fermentation system decreased, and the production of short-chain fatty acids was significantly enhanced. Furthermore, in vitro fermentation of TFPS altered the composition of gut microbiota, specifically in elevating the ratio of Bacteroidetes to Firmicutes and enriching Prevotella. The present results suggest that TFPS has the potential to be developed as functional foods to modify gut microbiota.