Diversity of yeast with β -glycosidase activity in vanilla (Vanilla planifolia)plant

Microbial contribution to vanilla flavour development
has not been fully investigated. The precursor molecules
of vanillin are converted to vanillic acid by
β -glycosidase enzyme. Contribution of β -glycosidase
enzyme from plant and microbial sources during the
process of curing is yet to be fully understood. In the
present work the diversity of yeast from rhizosphere
soil in curing and storing of bean has been studied.
Yeast with β -glycosidase activity was 0.47% in the
field, which increased to 1.75% during curing of the
total diversity. A total of 4655 isolates with 86 morphological
different colonies were screened, of which
35 forms belonging to 17 genera were found to be β -
glycosidase producers. Further testing for their ability
to convert ferulic acid to vanillic acid proved all the 35
forms utilized ferulic acid. Bullera sp. (MVY22) was
found to be the most promising, which was further
investigated for its conversion ability. HPLC analysis
proved the conversion of ferulic acid to vanillic acid
by this isolate.