The strains were cultured in a 50-mL shake-flask system of fermentation medium containing 10 g glucose, 20 g oat meal,
25 g dextrin, 10 g peptone, 5 g fish meal, 2 g yeast extract, and
3 g CaCO3 in1 000 mL distilled water (pH 7.2−7.4) at 28 ± 2 o
C
for 7 days, with continuous shaking at 200 r·min−1
. After
fermentation, each individual culture broth was extracted with
25 mL of n-butanol for 30 min. The organic solvent extract was
separated after centrifugation (2 000 g) for 10 min,
concentrated with rotary evaporators, and cryodesiccated into
arid extract, which was quantified for further bioactivity
screening analysis