Aug 2017 DOI 10.14302/issn.2471-2140.jaa-17-1541
Yu ZhiCorresponding author
College of Horticulture and Forestry Science, Huazhong Agricultural University, Key Laboratory of Horticultural Plant Biology, Ministry of Education, No. 1 Shizishan Street, Hongshan District, Wuhan City, Hubei Province, China 430070
In the present study, we investigated the chemical compositions, in vitro antioxidant and in vivo hepatoprotective activities of two tea polysaccharides (TPS), which were extracted from two different tea cultivars, Yingshuang (Camellia Senesis, T01) and Yunnan Dayezhong (Camellia Senesis, T09). Compared with T09-TPS, T01-TPS had lower contents of neutral sugar, protein, uronic acid and polyphenol. However, T01-TPS showed stronger scavenging abilities for transient free radicals of hydroxyl radical and superoxide anion radicals and lipid peroxidation inhibition effect, but weaker scavenging ability for stable free radical of DPPH. For hepatoprotective activity in vivo, the results demonstrated that both T01-TPS and T09-TPS could significantly prevent the increase of serum alanine aminotransferase and, aspartate aminotransferase levels, decrease the liver index, reduce the formation of malonydialdehyde and enhance the activities of superoxide dismutase, glutathione peroxidase and peroxidase in carbon tetrachloride-induced liver injury mice. These results suggest that T01-TPS and T09-TPS have potent antioxidant and hepatoprotective activities.
Dec 2019 DOI 10.14302/issn.2690-4829.jen-19-3105
Brumm PhillipCorresponding author
C5-6 Technologies LLC, 5627 Old Oak Drive, Fitchburg, WI 53711, USA
Trichoderma reeseiβ-glucosidase (Bgl1) is one of four enzymes demonstrated to act synergistically to degrade cellulose both in vitro and in vivo. Our work attempted to better understand the substrate specificity and potential biotechnological applications of Bgl1. T. reesei Bgl1H cleaves over 80% of the β-(1-4) and β-(1-3) linkages in β-glucan and 14% of the β-(1-4) linkages in amorphous cellulose, significantly more than any tested bacterial β-glucosidase. Bgl1H cleaves 50% of the β-(1-4) linkages in xyloglucan when supplemented with cellulase and α-xyloside. Approximately 20% conversion to glucose was obtained from insoluble β-(1,3)-linked curdlan using only Bgl1H; addition of a curdlanase resulted in conversion of approximately 70% of the curdlan to glucose. Bgl1H also produces xylose from xylooligosaccharides and debranched xylans. For both glucans and xylans, the relative rates of hydrolysis increase with increasing polysaccharide chain lengths. Bgl1H is able to partially degrade β-glucan in a variety of grain components; addition of endo-acting enzymes improved the enzyme’s performance on these grain components. The ability of this enzyme to produce monosaccharides from undigestible polysaccharides suggest it may have potential in improving utilization of carbohydrates in animal feed, fermentations, and other biotechnological applications.