ASSESSMENT OF TOTAL PHENOLIC, TOTAL FLAVONOID, METAL CONTENTS AND ANTIOXIDANT ACTIVITIES OF Trametes versicolor AND Laetiporus sulphureus

Abstract

In this study, total phenolic and flavonoid contents, biologically important antioxidant activities and precious metal contents of Trametes versicolor (L.) Lloyd and Laetiporus sulphureus (Bull.) Murrill fruiting bodies collected from Kastamonu province with their unique appearances and growing environments were deter-mined. The content of phenolics in methanolic extracts expressed in gallic acid equivalents varied between 77.41 ±1.10 and 272,70 ±2.26 mg/g for T. versicolor and L. sulphureus, respectively. Also, the content of flavonoids in methanolic extracts expressed in quercetin equivalents varied between 13.82 ±0.21 and 44.29 ±0.54 mg QE/mg for T. versicolor and L. sulphureus, respectively. Antioxidant activity of mushroom extracts were expressed as percentage of DPPH radical inhibition and IC50 values. Percentage of inhibition ranged from 15.83% to 61.03% with IC50 value of 5.33 mg/mL for L. sulphureus, while 7.27% to 20.47% with IC50 value of 18.10 mg/mL was obtained for T. versicolor. In addition, mushroom samples were examined for metal content by ICP-OES. While the most abundant precious metals of fruiting bodies were Ca (23.91 ±0.14), P (17.11 ±0.05), Mg (6.77 ±0.02) and Fe (3.84 ±0.02) as mg/kg DW for T. versicolor, they were P (24.52 ±0.09), Mg (4.59 ±0.01), Ca (0.49 ±0.01), and Fe (0.49 ±0.02) as mg/kg DW for L. sulphureus. The results showed that these two mushroom species rich in total phenolic contents can also be a very valuable source of P and Mg. While heavy metals Cu (123.93 ±0.30), Ni (180.99 ±0.64), Pb (54.62 ±0.58), and Cr (35.27 ±0.33) were found as µg/kg DW for T. versicolor, Cu (36.36 ±0.53), Ni (41.51 ±0.86), Pb (3.50 ±1.26), and Cr (8.23 ±0.55) were found as µg/kg DW for L. sulphureus.