Strong Radical Scavenging Macrofungi from the Dry Zone Forest Reserves in Sri Lanka

Authors:

Dilusha Fernando, Ravi Wijesundera, Preethi Soysa, Dilip de Silva, Chandrika Nanayakkara

Abstract: Natural metabolites produced by macrofungi are of great interest as potential antioxidant defensive agents to reduce the oxidative damage caused by free radicals. Primarily, phenolic and flavonoid type metabolites have gained major importance due to the strong capacity of scavenging free radicals. The study was mainly focused to investigate the natural antioxidant properties of macrofungi found in Sri Lankan dry zone forest reserves using DPPH radical scavenging assay and to find out the contribution of phenol and flavonoid substances towards their antioxidant capacity. EC₅₀ values of all extracts were below 1.2 mg/ml. Among the analyzed specimens, Phellinus repandus and Inonotus porrectus showed the most potent antioxidant activities having EC₅₀ of 7.91 ± 1.38 µg/ ml and 19.70 ± 0.17 µg/ ml, respectively. Ten fungal forms exhibited EC₅₀ < 300 µg/ ml and eighteen showed a mean values of EC₅₀ in the range of 300-1200 µg/ ml. Further, P. repandus and I. porrectus also exhibited the highest level of total phenols and flavonoids. EC₅₀ values of the species studied were inversely related to the total phenol and flavonoid contents.The analyzed macrofungi specimens exhibited high antioxidant power highlighting their potential as therapeutically useful antioxidant agents. Particularly, P. repandus and I. porrectus could be an important source of novel antioxidant compounds. In addition, phenol and flavonoid compounds largely contribute to the scavenging activity of studied macrofungi.

Keywords: Macrofungi, Antioxidant Activity, Phenol Content, Flavonoid Content,EC₅₀

_{Read full scientific paper in} Frontiers in Environmental Microbiology.