Comparative phytochemical and anti-bacterial studies of two indigenous medicinal plants Curcuma caesia Roxb. and Curcuma aeruginosa Roxb

Abstract

Background: Traditional medicinal plants could serve as a good supply of new dependable, biodegradable, renewable drugs and can be utilised for its anti‑bacterial activity directly or indirectly. Aims: To evaluate the phytochemical and anti‑bacterial properties of two morphologically similar indigenous medicinal plants Curcuma caesia and Curcuma aeruginosa belonging to the family Zingiberaceae. Materials and Methods: Evaluation of rhizome extracts using methanol was performed for the presence of active principles. Qualitative analysis was carried out for diverse phytoconstituents. Different concentrations (1.25, 2.5, 5.0 mg/ml) of hexane, chloroform, ethyl acetate, acetone, methanol and water serial extracts from the rhizome of C. caesia and C. aeruginosa were tested against Gram positive (Staphylococcus aureus, Streptococcus haemolyticus and Bacillus cereus) and Gram negative (Salmonella typhi, Enterobacter aerogens, Vibrio cholerae, Pseudomonas aeruginosa and Serratia marcescens) bacteria. National Committee for Clinical Laboratory Standard (NCCL) standards were strictly followed to perform anti‑bacterial disc susceptibility test using disc diffusion method. Statistical Analysis: All the values of the results were expressed as means of two independent experiments ± standard deviation. Results: Phytochemical screening of these two plants confirmed the presence of various bioactive substances and thus validating its use in herbal remedies. Anti‑bacterial studies showed varying degree of inhibitory action against all the tested bacteria. Among the Gram positive bacteria, acetone extract of C. caesia showed maximum activity against S. aureus and hexane extract of C. aeruginosa exhibited maximum activity against B. cereus. In Gram negative bacteria, chloroform extract of C. caesia showed maximum inhibitory action against S. marcescens, whereas the methanol extract of C. aeruginosa showed higher inhibitory action against S. typhi. Conclusions: The findings about present study suggest that the rhizome extract possess excellent anti‑bacterial potential that can be used for therapeutic purposes for many bacterial infectious diseases with proper evaluation procedures. The present study validated the use of these plants in traditional medicine and recommends for making new pharmaceuticals for therapeutic needs. Key words: Anti‑bacterial activity, Curcuma aeruginosa, Curcuma caesia, medicinal plants, plant extracts