149-55-3Relevant academic research and scientific papers
Substrate specificity of beta-primeverosidase, a key enzyme in aroma formation during oolong tea and black tea manufacturing.
Ma,Mizutani,Hiratake,Hayashi,Yagi,Watanabe,Sakata
, p. 2719 - 2729 (2007/10/03)
We synthesized nine kinds of diglycosides and a monoglycoside of 2-phenylethanol to investigate the substrate specificity of the purified beta-primeverosidase from fresh leaves of a tea cultivar (Camellia sinensis var. sinensis cv. Yabukita) in comparison with the apparent substrate specificity of the crude enzyme extract from tea leaves. The crude enzyme extract mainly showed beta-primeverosidase activity, although monoglycosidases activity was present to some extent. The purified beta-primeverosidase showed very narrow substrate specificity with respect to the glycon moiety, and especially prominent specificity for the beta-primeverosyl (6-O-beta-D-xylopyranosyl-beta-D-glucopyranosyl) moiety. The enzymes hydrolyzed naturally occurring diglycosides such as beta-primeveroside, beta-vicianoside, beta-acuminoside, beta-gentiobioside and 6-O-alpha-L-arabinofuranosyl-beta-D-glucopyranoside, but were unable to hydrolyze synthetic unnatural diglycosides. The purified enzyme was inactive toward 2-phenylethyl beta-D-glucopyranoside. The enzyme hydrolyzed each of the diglycosides into the corresponding disaccharide and 2-phenylethanol. These results indicate the beta-primeverosidase, a diglycosidase, to be a key enzyme involved in aroma formation during the tea manufacturing process.
Structural studies of a polysaccharide isolated from the green seaweed Chaetomorpha anteninna
Rao, E. Venkata,Ramana, K. Sri
, p. 163 - 170 (2007/10/02)
Extraction of the green seaweed Chaetomorpha anteninna with water, followed by fractionation using the copper complex, gave a sulphated heteropolysaccharide, 27D +84 deg, that contained arabinose (57.7 percent), galactose (38.5 pe
