The sensitivity of two Gram positive (Staphylococcus aureus and Bacillus subtilis) and two Gram negative (Escherichia coli and Pseudomonas aeruginosa) pathogenic multi-drug resistant bacteria was tested against the crude extracts (cold aqueous, hot aqueous, and methanol extracts) of leaves and seeds of Argemone mexicana L. (Papaveraceae) by agar well diffusion method. Though all the extracts were found effective, yet the methanol extract showed maximum inhibition against the test microorganisms followed by hot aqueous extract and cold aqueous extract.Key words: Argemone mexicana -medicinal plant -antibacterial activity Medicinal plants being the effective source of both traditional and modern medicines, are genuinely useful for primary health care. Over the years, World Health Organization (WHO) advocated traditional medicines as safe remedies for ailments of both microbial and non-microbial origins (WHO 1978).Some antibiotics have become almost obsolete because of drug resistance (Ekpendu et al. 1994) and consequently new drugs must be sought for. Herbal treatment is one possible way to treat diseases caused by multidrug resistant bacteria (Olukoya et al.1993).Though pharmacological industries have produced a number of new antibiotics in the last three decades, yet resistance to these drugs by microorganisms has developed. In general, bacteria have the genetic ability to transmit and acquire resistance to drugs, which in turn may be utilized as therapeutic agents (Cohen 1992).The use of plant extracts and phytochemicals, with known antibacterial properties, may be of immense importance in therapeutic treatments. In the past few years, a number of studies have been conducted in different countries to prove such efficiency (Ikram & Inamul 1984, Almagboul et al. 1985, Sousa et al. 1991, Kubo et al. 1993, Shapoval et al. 1994, Artizzu et al. 1995, Izzo et al. 1995 several countries. In Mexico, the seeds are considered as an antidote to snake venom. In India, the smokes of the seeds are used to relieve toothache. The fresh yellow, milky seed extract contains protein-dissolving substances, effective in the treatment of warts, cold sores, cutaneous infections, skin diseases, itches, and also dropsy and jaundice (Chopra et al. 1986).The present study has been designed to determine the role of seeds and leaf extracts (cold aqueous, hot aqueous, and methanol extracts) of A. mexicana for potential antibacterial activity, if any, against two Gram positive bacteria (Staphylococcus aureus MTCC 2940 and Bacillus subtilis MTCC 441) and two Gram negative bacteria (Escherichia coli MTCC 739 and Pseudomonas aeruginosa MTCC 2453).
MATERIALS AND METHODSThe plant material used in this study consisted of leaves and seeds of A. mexicana, collected from a village named Lakudi of Burdwan district (23°16'N, 87°54'E), WB, India, during spring (mid-March to mid-April 2004). The leaves and seeds were initially rinsed with distilled water and dried on paper towel in laboratory at (37 ± 1) o C for 24 h.
Preparation and preservation of plant ...
