2018, Vol. 6, Issue 2, Part C

author(s)
Mahmuda Ferdous, Mohammad Anwarul Basher, Ibrahim Khan, Firoz Ahmed, Md. Shariful Islam Sobuz and AFM Shahid Ud Daula

abstract
Alpinia calcarata Roscoe (Zingiberaceae) has been widely used by indigenous communities in Sri Lanka, India, and Bangladesh as a traditional remedy for indigestion, impurities of blood and respiratory ailments. The present study was conducted to evaluate the phytochemicals, antioxidant and antibacterial activities of methanolic extract of leaves of A. calcarata. The total phenolic content (TPC), total flavonoid content (TFC), and total flavonol content (TFlC) were determined using spectrophotometric methods. Phytochemical screening revealed presence of alkaloid, steroid and anthraquinones with considerable amounts of phenolic compounds. To evaluate the antioxidant activities of the plant extract, 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, reducing power activity (RPA) assay and ferric-reducing antioxidant power (FRAP) assay were used. The leaves extract also exhibited remarkable antioxidant potentials as compared to the reference standard- ascorbic acid (AA) and butylated hydroxytoluene (BHT). The disc-diffusion method was conducted to evaluate the antibacterial property; methanolic extract of leaves had no antibacterial (gram-positive and gram-negative) activity. The results suggest that leaves extract of A. calcarata could be a potential source of natural antioxidants for use in food, cosmetics and pharmaceuticals industries.