Medicinal plants of the Western ghats as possible inhibitors of oxidation in various biological lipid substrates

Abstract

Medicinal plants are nature’s fighters against several degenerative diseases. The reverse pharmacological approach focuses on traditional knowledge on the usage of medicinal plants for various diseases and revalidating the effect using modern techniques. The Western ghats of Southern India has sheltered a wide range of medicinal plants. The objective of this research work was to evaluate the oxidation inhibiting ability of aqueous extract of four medicinal plants from the Western ghats, namely; Andrographis paniculata (Burm.f.) Wall. ex Nees, Costus speciosus (Koen.) Sm., Canthium parviflorum Lam. and Abrus precatorius L. in biological lipid substrates, viz., cholesterol, low-density lipoprotein and brain homogenate. The IC50 values of the plant extracts were calculated and the correlation between the phytochemicals and the antioxidant effect exhibited was studied. From the results, it was observed that, the inhibition of oxidation by the aqueous extract of all the four medicinal plants, followed the order cholesterol >LDL> brain homogenate. C. parviflorum exhibited highest antioxidant activity in cholesterol (94.8%) and brain (37.35%) than compared to other medicinal plants. In LDL, the highest antioxidant activity (73.75%) was exhibited by C. speciosus. The antioxidant activity of CP and CS in the substrates correlated well with the polyphenol and flavonoid content of the extracts. The IC50 values of CS in cholesterol (305 μg, r2 = 0.9972) was the least among all the medicinal plants. The overall protective action in the substrates was higher in C. parviflorum than other medicinal plants. Thus, the selected medicinal plants can be further explored for its biological activity and utilized as sources of natural antioxidants and phytochemicals against various oxidative stress related diseases.