Effect of Citrus Waste Substrate on the production of Bioactive Component, and Antioxidant and Antitumor Activity of Grifola frondosa

The contents of bioactive compounds, and antioxidant and anticancer activities of Grifola frondosa cultivated on citrus waste substrates such as citrus peel and premature Hallabong fruit drop were investigated in the present study. The total phenolics and naringin were 80- and 500-folds higher in the extracts from Grifola frondosa mycelia cultivated on citrus waste than those in the extracts of Grifola frondosa mycelia cultivated on the sawdust, which was reported in the previous findings. Moreover, IC50 values of the extracts from Grifola frondosa mycelia cultivated on citrus waste in the DPPH radical scavenging assay were much lower than that of mushroom cultivated on the conventional substrate. The premature Hallabong mushroom extract showed the highest phenolic content (126.7 mg/g) and the best antioxidant activity. The IC50 values of the premature Hallabong mushroom extract were 0.52, 0.38 and 0.46 mg/mL in the DPPH radical scavenging, superoxide radical scavenging and xanthine oxidase inhibition assays, respectively. Anticancer effects of Grifola frondosa cultivated on citrus waste in human colon and breast cancer cells were analyzed. Results demonstrated that Grifola frondosa cultivated on citrus waste exhibited antiproliferative effects in both HT-29 and MCF-7 cancer cells. Taken together, citrus waste can be utilized as a viable substrate to improve the antioxidant and anticancer activities as well as to increase total phenolic content of Grifola frondosa. [Jung Hyun Kim, Min Young Kim. Effect of Citrus Waste Substrate on the production of Bioactive Component, and Antioxidant and Antitumor Activity of Grifola frondosa. Life Science Journal. 2011; 8(3):564-571] (ISSN: 1097-8135). http://www.lifesciencesite.com.