D-saccharic acid-1,4-lactone Producing Acetic Acid Bacteria in Kombucha Fermentation Process

Kombucha is a refreshing beverage with a slightly sour taste, obtained by the fermentation of probiotic microorganisms. The main compositions include acetic acid, lactic acid, gluconic acid, glucuronic acid as well as Dsaccharic acid-1,4-lactone (DSL). D-Saccharic acid-1,4-lactone (DSL) is a crucial substance involved in liver detoxification. DSL has ability to inhibits the activity of ?-glucuronidase, an enzyme related with cancers. The objective of this study was to isolate acetic acid bacteria which produced DSL from fruit, fermented fruit juices and kombucha. One hundred and fifty-three isolates of acetic acid bacteria were obtained from pineapple, 7 fermented fruit juices and 3 samples of kombucha. Sixty-eight isolates had ability to produced acid from green tea broth. They were selected for DSL production and compared with Acetobacter tropicalis P6. It was found that fourteen isolates, PM20, PM30, PM31, PM35, PM36, PM56, PM60, PM70, PM99, PM103, PM123, PM131, PM135, PM136 and A. tropicalis P6 gave the yield of DSL between 0.02 to 0.33 mg/ml.