Isolation, Screening And Identification Of Rutin-decomposing Strains

Quencetin and isoquercetin are flavonoids, which have outstanding drug activities, andthe methods of production are research focus in recent years. This experiment set up a methodof isolating and screening active strains. The strains were isolated from soil samples collectedfrom Sophora japonica L. tree forest of Hebei University campus through dilution coatingmethod. Active rutin decomposing strains were screened by using thin layer chromatography(TLC) method and high performance liquid chromatography (HPLC) method, and thetransformation ability of active strains were determinated by using HPLC. Finally, the activestrains were identified based on morphological and phylogenetic characteristics.Altogether,9active strains contained7strains, D3, Z43, Z46, Z50, Z54, Z55and Z58,which could transfrom rutin into quercetin and2strains, C44and Z9, which could convertrutin to isoquercetin, were obtained. Transformation ability of9active strains weredetermined at different time, and the results showed that the quality of quercetin andisoquercetin would be increasing within a certain time, but the quality would be decreasingwhen the quality achieve to maximum as the continuous extension of time. Throughcompared different transformation time spectrum diagram, it was deduced that the activestrains could secrete a series of enzymes. C44, Z50, Z55strains were higher activity among ofthem.The sugars in transfered products were determined through TLC detection. The resultssuggest that strains D3, Z43, Z46, Z50, Z54, Z55and Z58could screate β-rutinosidase whichdegraded rutin to quercetin, and strains C44, Z9could screate α-rhamnosidase whichdegraded rutin to isoquercetin.The9active strains were identified based on morphological and phylogenetic features.Strain D3was identified as Paenibacillus glucanolyticus, and16S rDNA sequence similaritywas99.9%. Strain C44was identified as Bacillus litoralis, and16S rDNA sequence similaritywas98.1%. Strain Z9could be identified as Aspergillus flavus, and18S rDNA sequencesimilarity was100%. Strains Z43, Z50and Z54were identified as Penicillium decumbens,and18S rDNA sequence similarity was99.8%. Strains Z46, Z55and Z58were identified asPenicillium spp.