Ilex khasiana - The silent holly species of Aquifoliaceae on its pharmacognostical importance as a free radical scavenger and antibacterial agent

Abstract

Ilex khasiana is a rare and endangered medicinal plant endemic to northeast India. Remaining largely unexplored, it is purported to have a range of medicinal values and may soon join the medicinal plant hall of fame. Extracts of the leaves were prepared using solvents of increasing polarity, namelypetroleum ether (IKP), chloroform (IKC) and methanol (IKM). The preliminary phytochemical screening indicated the presence of alkaloids, phytosterols, triterpenoids, saponins, reducing sugars, glycosides and carbohydrates. Free radical-scavenging activity was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH). IKC exhibited the highest activity with an  IC₅₀ of 17.22 ± 1.87, followed by IKM with an  IC₅₀ of 26.93 ± 5.14 and IKP with an  IC50 of 37.16 ± 5.11. Butylated hydroxytoluene (BHT) was used as the standard DPPH scavenger and showed an IC₅₀ of 8.31 ±0.72. IKM and IKC also showed positive antibacterial activity against Gram-negative bacteria such as Escherichia coli, Pseudomonas aeruginosa, and Klebsiella, and a Gram-positive bacteria Bacillus subtilis. IKP did not indicate any inhibition against the selected bacteria. Our findings substantiate the basis for further investigations on the medicinal potentials of the plant.