Ethnobotanical Leaflets 12: 1022-28. 2008.
In vitro Phytochemical Screening and Antibacterial Activity of Organic Leaf
Extracts of Spathodea campanulata P. Beauv against Hospital Isolated Bacterial
*Rangasamy Dhanabalan, Asirvatham Doss, Subbu Balachandar,
Ethiraj Kezia, Muthusamy Jagadeeswari and Haldurai Karthik
Department of Microbiology, Centre for Post Graduate Studies in Microbiology
RVS College of Arts and Science, 242 –B KVK Thottam,Trichy Road,
Coimbatore-641 402, Tamilnadu, India.
*Corresponding author: email@example.com
Issued 17 November 2008
Spathodea campanulata P. Beauv is extensively used in Indian traditional and folklore medicines to cure
various human ailments. The preliminary phytochemical screening of the leaves revealed the presence of alkaloids,
flavonoids, saponins, tannins, steroids and terpenoids. In vitro antibacterial studies of the leaf extracts were carried
out on eight medically important bacterial strains using agar disc diffusion method. The antibacterial assay using
petroleum ether leaf extracts showed good inhibitory activity against Klebsiella pneumoniae and compared with
standard antibiotic Streptomycin.
Key words: Spathodea campanulata, Phytochemical Screening, Leaf extracts and Antibacterial activity.
Infectious diseases are the leading cause of death worldwide. The clinical efficacy of many existing
antibiotics is being threatened by the emergence of multidrug-resistant pathogens (Bandow et al., 2003). Bacterial
and fungal pathogens have evolved numerous defense mechanisms against antimicrobial agents, and resistance to
old and newly produced drugs is on the rise. The increasing failure of chemotherapeutics and antibiotic resistance
exhibited by pathogenic microbial infectious agents has led to the screening of several medicinal plants for their
potential antimicrobial activity (Colombo and Bosisio 1996; Scazzocchio et al., 2001). There are several reports in
the literature regarding the antimicrobial activity of crude extracts prepared form plants (El-Seedi et al., 2002; Rojas
et al., 2003; Duraipandiyan et al., 2006; Parekh and Chanda, 2007a).The use of traditional medicine and medicinal
plants in most developing countries, as a normative basis for the maintenance of good health, has been widely
observed (UNESCO, 1996). Furthermore, an increasing reliance on the use of medicinal plants in the industrialized
societies has been traced to the extraction and development of several drugs, chemotherapeutics from these plants as
well as from traditionally used rural herbal remedies (UNESCO, 1998). The practice of traditional medicine is
widespread in China, India, Japan, Pakistan, Sri Lanka and Thailand. The results of investigation performed in the
(mg/ml) (mg/ml) (mg/ml)(mg/ml)
105 2.5105 2.5 105 2.5 105 2.5105 2.5
109- 1097 1097
mm- Zone of inhibition in millimeter, mg-Concentration of the leaf extracts in organic solvents.