tailieunhanh - Isolation of dihydroxyacetone-producing acetic acid bacteria in Vietnam

Sixty-six acetic acid bacteria (AAB) were isolated from fourty-five flowers and fruits collected in Hochiminh City, Vietnam. Of the sixty-six, thirty-one isolates were selected as dihydroxyacetone (DHA)-producing AAB based on the reaction with Fehling’s solution and grouped into three groups by routine identification with phenotypic features. | TAÏP CHÍ PHAÙT TRIEÅN KH&CN, TAÄP 19, SOÁ T5- 2016 Isolation of dihydroxyacetone-producing acetic acid bacteria in Vietnam Vu Thi Lan Huong Nguyen Thi Kim Oanh Bui Thi Thu Van Bui Thi Tu Uyen Ngo Dai Nghiep Dang Thi Phuong Thao University of Science, VNU-HCM Pattaraporn Yukphan National Center for Genetic Engineering and Biotechnology (BIOTEC), NSTDA, Thailand (Received on 1st December 2015, accepted on 2nd December 2016) ABSTRACT Sixty-six acetic acid bacteria (AAB) were isolated from fourty-five flowers and fruits collected in Hochiminh City, Vietnam. Of the sixty-six, thirty-one isolates were selected as dihydroxyacetone (DHA)-producing AAB based on the reaction with Fehling’s solution and grouped into three groups by routine identification with phenotypic features. Group I composed of fourteen isolates and was assigned to the genus Acetobacter, Group II composed of thirteen isolates and was assigned to the genus Gluconobacter and Group III was the remaining four isolates and was assigned to the genus Gluconacetobacter. Ten isolates among the thirteen isolates of Group II gave a larger amount of DHA (– mg/mL) than Gluconobacter oxydans NBRC 14819T ( mg/mL), promising for the potential use in producing DHA. In phylogenetic analysis based on 16S rRNA gene sequences, six isolates of the ten potential DHA producers were suggested to be candidates for new taxa in the genus Gluconobacter. Key words: acetic acid bacteria, dihydroxyacetone-producing, Gluconobacter INTRODUCTION The production of dihydroxyacetone (DHA) is of interest in various applications in cosmetic, medicine, pharmaceuticals and food industries and in very cheap cost of glycerol, as the substrate for DHA production, due to the overproduction of this material by the biodiesel industry [10]. In acetic acid bacteria, strains assigned to Gluconobacter oxydans are widely used in the production of DHA through a microbiological method [6, 8]. Except for strains of the genus .