IN VITRO ANTIBACTERIAL PROFILE OF ALSTONIA VENENATA R. BR-A COMPARATIVE STUDY
Keywords:Alstonia venenata, Anti bacterial, Leaf, Stem-bark, Root-bark, Fruit, Flower
Objective: To investigate the antibacterial efficacy of leaves, stem-bark, root-bark, flowers and fruits of Alstonia venenata R. Br.
Methods: The antimicrobial efficacy of butanol and methanol solvent extracts was evaluated by agar well diffusion against selected pathogenic bacterial strains. Gram negative strains like Pseudomonas aerugenosa, Proteus vulgaris, Escherichia coli, Klebsiella pneumoniae, Slamonella enteric typhimurium, Salmonella typhi, Salmonella paratyphi A, Shigella spp. were tested. Gram positive strains tested were Micrococcus luteus and Staphylococcus aureus. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined using macro broth dilution method against clinical isolate of Staphylococcus aureus. Streptomycin 0.125 mg/ml was used as positive control and Dimethyl sulfoxideÂ (DMSO) as the solvent control.
Results: Butanol and methanol extracts of all the plant parts are highly effective against Gram positive strains and show moderate inhibition against Gram negative strains. Stem-bark and root-bark butanol were the most effective fractions followed by fruit, flower and leaf extracts. The inhibition zones of Micrococcus luteus and Staphylococcus aureus were 24-26 mm and 18-20 mm respectively. The observed zone size was equal to or greater than the positive control used. The MIC value for stem-bark butanol and root-bark butanol were 0.98 mg/ml and the MBC values were 7.8 mg/ml and 3.9 mg/ml respectively. For fruit, flower and leaf butanol the MIC values were 15.6, 31.25 and 125 mg.
Conclusion: The extracts were highly active against Gram positive strains than Gram negative strains. The butanol extracts were the most active fraction followed by the methanol extracts. Highest activity was observed for root-bark and stem-bark followed by fruit, flower and leaf extracts.
Purohit SS, Vyas SP. Medicinal plants cultivation a scientific approach including processing and financial guidelines. 1st ed. Jodhpur, India: Agrobios publishers; 2004.
Ahmad I, Mehmood Z, Mohammad F. Screening of some Indian medicinal plants for their antimicrobial properties. J Ethnopharmacol 1998;62:183-93.
Samy RP, Ignacimuthu S. Antibacterial activity of some folklore plants used by tribals in western ghats of India. J Ethnopharmacol 2000;69:63-71.
Gamble JS. Flora of the Presidency of Madras. Vol. 1. BSI; 1921.
Varier VPS, Nambiar VPK, Ramankutty C. Indian medicinal plants. A compendium of 500 Species Vol. 1. 1st ed. Himayatnagar, Hyderabad, India: Orient Longman; 1994.
Govindacharia TR. Contribution from Indian laboratories to the chemistry of plant products. Proc Indian Acad Sci (Chem Sci) 1984;93:491-502.
Govindachari TR, Viswanathan N, Pai BR, Savitri TS. Chemical constituents of Alstonia venenata R. Br. Tetrahedron Lett 1964;5:901-6.
Bhattacharya SK, Ray AB, Guha SR. Psychopharmacological studies on echitovenidine. Pharmacol Res Commun 1976;8:159-66.
Singh UP, Sharma BK, Mishra PK, Ray AB. Antifungal activity of venenatine, an indole alkaloid isolated from Alstonia venenata. Folia Microbiol 2000;45:173â€“6.
Williams SJ, Thankamani V. Antibacterial activity of the crude leaf and stem bark extracts of Alstonia venenata R. Br. Icfai. J Life Sci 2007;1:71â€“7.
Wayne PA. Performance standards for antimicrobial susceptibility testing, nineteenth informational supplement CLSI document, M100-S19; 2009. p. 136-9.
Thankamani V, James J, Dev L. Phytochemical screening and antimicrobial activity of Alstonia Scholaris Flower. Int J Pharm Res Dev 2011;3:72-178.
CLSI. Clinical and Laboratory Standards Institute. Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically. Approved standard M7-A7. 7th ed. CLSI Wayne PA USA; 2006. p. 26.
Chinmayee MD, Deepthi SR. Screening for bioactive properties and phytochemicals in Alstonia venenata R. Br. Proceedings of 22nd. Kerala Science Congress; 2010. p. 789-90.
Misra CS, Pratyush K, Sagadevan LDM, James J, Veettil AKT, Thankamani VA. Comparative study on phytochemical screening and antibacterial activity of roots of Alstonia scholaris with the roots leaves and stem bark. Int J Res Phytochem Pharmacol 2001;1:77-82.
James J, Veettil AKT, Pratyush K, Misra CS, Dev L, Sagadevan M, et al. Phytochemical investigation and antibacterial activity of the fruits of Alstonia scholaris. Int J Phytopharmacol 2012;3:74-7.
Hussain A, Zaman MK, Ramteke AM. Antibacterial activity of trunk bark of Alstonia scholaris. Asian J Pharm Clin Res 2010;3:46-7.
J Koteswara Rao, TVV Seetharami Reddi, O Aniel Kumar. Ethnobotany of stem bark of certain plants of visakhapatnam district, Andhra Pradesh. Curr Bot 2011;2:1-6.
Khan MR, Omoloso AD, Kihara M. Antibacterial activity of Alstonia scholaris and Leea tetramera. Fitoterapia 2003;74:736â€“40.