Phytochemical screening and antibacterial potential of Methanol, Ethanol and aqueous extracts from Seed, Bark and Leaf of Bauhinia tomentosa L.

Bauhinia tomentosa L. leaves, flower buds or root had been reported to possess anti-diabetic, anti-pyretic, antioxidant, anti-proliferative properties. The seeds and bark of the plant had not still studied for their anti-bacterial properties despite their uses in traditional medicines.

Solvent extraction method was used to prepare crude aqueous, methanol and ethanol extracts of leaf, seed and bark, used for phytochemical screening to determine the classes of metabolites present. Anti-bacterial activity of leaf, seed and bark extracts was evaluated using agar well diffusion assay. Minimum inhibitory concentration (MIC) of extracts was examined using broth dilution assay.

Qualitative phytochemical analysis of aqueous seed extract revealed the presence of maximum number of phytochemicals (alkaloids, glycosides, flavonoids, phenols, saponins, tannins, terpenoids and amino acids). Aqueous and methanol seed extracts were observed to be effective against all the tested bacteria viz. Enterobacillus, Micrococcus, Klebsiella pneumoniae, Streptococcus thermophilus and Haemophilus influenza. On the other hand, all the leaf extracts (ethanol, methanol and aqueous) showed inhibition against Enterobacillus, Micrococcus, S. thermophilus and H. influenzae except K. pneumoniae. The aqueous extracts of seed, leaf and bark was observed to be more potent against all the Gram positive and Gram negative bacteria followed by methanol extracts of leaf and seed.