46C-10 |
Antioxidant properties of methanolic extracts from Ganoderma tsugae |
J. L. MAU1, S. Y. Tsai, Y. H. Tseng, and S. J. Huang. (1) Department of Food Science, National Chung-Hsing University, 250 Kuokuang Road, Taichung, 40227, Taiwan Ganoderma tsugae Murrill (Sung-shan-ling-chih or tsuga reishi) is a medicinal mushroom. Fruit bodies of this medicinal mushroom are found to be medically active in several therapeutic effects such as antitumor, immunomodulating and chronic bronchitis and commonly used for pharmaceutical purposes and as health food. Currently, baby fruit bodies (baby ling-chih) are popular in Taiwan. However, the antioxidant properties of this mushroom are not available. Our objective was to study and compare the antioxidant properties of methanolic extracts from G. tsugae fruit bodies, baby ling-chih, mycelia and filtrate from the submerged culture. Samples of G. tsugae were lyophilized, ground and extracted twice with methanol at the ratio of 1:10 (w/v) at 25 C overnight. The combined methanolic extracts were rotary evaporated to dryness and redissolved in methanol for assays of antioxidant attributes. Antioxidant properties assayed included antioxidant activity in the conjugated diene method, reducing power, scavenging effect on 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical and chelating effect on ferrous ion. For all methanolic extracts, mature and baby fruit bodies showed excellent antioxidant activities (96.8 and 93.6%) at 20 mg/mL, higher than those of mycelia and filtrate (19.3 and 23.6%), respectively. At 5 mg/mL, reducing powers of baby fruit bodies, mycelia and filtrate were similar (0.93~1.05) and much higher than that of mature fruit bodies (0.50). At 5 mg/mL, scavenging effects were in the order of baby fruit bodies (93.8%) > mature fruit bodies (88.4%) > filtrate (71.9%) > mycelia (49.9%). At 10 mg/mL, chelating effect were in the order of baby fruit bodies ~ filtrate (91.2~93.3%) > mycelia (85.9%) > mature fruit bodies (66.2%). These results showed that the methanolic extract from baby ling chih possessed excellent antioxidant properties. Therefore, the use of baby ling chih for pharmaceutical purposes and as health food would be beneficial.
Session 46C, Food Chemistry: Lipids, antioxidants and emulsifiers
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