Abstract:

The present research investigated the effects of eight different culture media (numbered as A through H) on the
nutritional composition, polyphenol contents and antioxidant activity (DPPH and ABTS free radical scavenging activities,
and reducing power) of Pleurotus ostreatus. Results showed that Pleurotus ostreatus from various culture media presented
differences in their nutritional composition, polyphenol contents and antioxidant activities. The highest contents of ash,
sugar and dietary fiber were detected in Pleurotus ostreatuses cultured with medium H, and the highest contents of water,
protein and fat were detected when the edible mushroom was cultured with media C, F and B, respectively. Differences in
all investigated mineral elements were seen in the Pleurotus ostreatus cultured with various culture media, and some of them
even showed great differences. Six fatty acids were found in different amounts among eight samples of Pleurotus ostreatus,
together with differences in polyphenol contents. Polyphenols reached the highest level when medium E was used. The
antioxidant activity was enhanced as the concentration of polyphenols (for both free and bound forms) increased. However,
the differences in each antioxidant activity of Pleurotus ostreatus cultured with various culture media varied with the
concentration of polyphenols.

Key words: culture medium, Pleurotus ostreatus, nutritional composition, polyphenol, antioxidant activity