Comparative in vitro Antioxidant Activity of Natural and Cultured Ophiocordyceps Sinensis
Ophiocordyceps sinensis is a high valued therapeutic fungus endemic to the alpine ecosystems of the Tibetan Plateau and surrounding Himalayas at an altitude of 3000–5000 msl. This fungus is widely used as an excellent performance enhancer in traditional Chinese medicine (TCM). The objective of this work was to determine and compare the antioxidant potential of methanolic extract of natural and in vitro cultured mycelium of O. sinensis. The antioxidant capacity of the samples was assessed using 2, 2-Diphenyl-1- pikrylhydrazyl (DPPH) free radical scavenging assay, hydroxyl radical eliminating ability, ferrous ion chelating activity and 2, 2’- azino-bis- [3-ethylbenzthiazoline-6- sulphonic acid) (ABTS) free radical scavenging assay. The methanolic extract of in vitro cultured O. sinensis showed enhanced antioxidant potential than the natural samples. The IC50 value of natural and in vitro cultured samples were 2.98 mg/ml and 2.81 mg/ml against DPPH, 3.28 mg/ml and 2.95 mg/ml against Hydroxyl radical and 4.94 mg/ml and 4.65 mg/ml against ABTS free radicals respectively. Both natural and cultured sample extract showed 81% and 86 % iron chelating activity at 1.6 mg/ml concentration. The results obtained herein allow one to conclude that in vitro cultured O. sinensis can be used as a good source of antioxidants as compared to natural one. Further, the better antioxidant activity suggests its role in preventing disorders like cancer, necrosis and aging, induced by reactive oxygen species (ROS).