Phytochemical evaluation and study of in vitro antioxidant potential of ethanolic and aqueous extracts of Amorphophallus campanulatus: a popular tuber of West Bengal

Abstract

The use of herbal medicines worldwide had provided an excellent opportunity to India to look for therapeutic compounds from our ancient system of therapy, Ayurveda, which can be utilized for development of new drug. Amorphophallus campanulatus is grown wild and cultivated all over India. It is very popular for its edible corms and leaves, especially in Assam and Bengal and is cultivated there as a common food crop. Since ancient time, it has been considered as medicinal plant in Sushruta Samhita and Ayurveda. It is recommended for different ailments like digestive disorders, piles, buccal ulcers and as liver stimulant in Dravyaguna Vigyan. So, the ethanolic and aqueous extracts of this tuber were screened for the presence of in vitro antioxidant potential against 2,2- diphenyl-1-picrylhydrazyl (DPPH) radical, ferric reducing power, hydroxyl radical, superoxide radical and lipid peroxidation. Total phenolic and flavonoid contents of both the extracts were also evaluated. IC₅₀ values of ethanolic and aqueous extract of Amorphophallus campanulatus represented 676.37 and 820.46 μg/ml respectively for DPPH ; 665 and 968.64 μg/ml respectively for hydroxyl radical scavenging activity; 703.33 and 1097.61 μg/ml respectively for superoxide radical scavenging activity and 842.83 and 1337.35 μg/ml respectively in case of lipid peroxidation inhibition. The total phenol for ethanolic and aqueous extract was estimated to be 194.4 ± 2.2 mg % w/w and 104.6 ± 1.24 mg % w/w respectively (mg Gallic acid equivalent per gm dry weight of sample) and that of flavonoid was 6.75 ± 1.2 mg w/w and 1.50 ± 0.23 mg % w/w respectively (mg of Rutin equivalent per gm dry weight of sample). Ethanolic extract shows maximum antioxidant capacity in comparison to aqueous extract and hence can be utilized in future as therapeutic agent against free radical induced oxidative stress.