Isolation and characterization of polyphenol oxidase- and peroxidase-producing Bacillus strains from fully fermented tea (Camellia sinensis).

摘要

Sixteen aerobic endospore-forming Bacillus spp. were isolated from samples of fully fermented tea leaves collected from 10 tea factories in Lahijan and Langrod (Gillan province, Iran). Bacillus spp. isolates were characterized in terms of their phenotypic characteristics, antibiotic susceptibility and cellular fatty acids composition. Based on the data obtained, 5 isolates of tea Bacillus spp. (TB), namely TB2, TB4, TB6, TB10 and TB12, were identified as B. subtilis strains. 2 isolates, TB1 and TB14, were recognized as B. licheniformis. 2 Bacillus spp. isolates, TB9 and TB16, were identified as B. sphaericus. Isolates TB5 and TB13 were shown to be B. pumilus. 2 isolates, TB7 and TB15, belonged to the species B. cereus. of the isolates, TB3, TB8 and TB11 showed different phenotypic traits, distinct antibiotic sensitivities and fatty acid profiles, and they may represent novel species. The isolates showed polyphenol oxidase (monophenol monoxygenase, EC 1.14.18.1) and peroxidase activities. The highest polyphenol oxidase and peroxidase activities were observed for Bacillus sp. TB3 and B. licheniformis TB14, respectively, where values of 5.48 and 3.73 units/ml were found.