The bioactive compounds from the different parts of medicinal plants have shown many pharmacological activities but the screening for microbial activity from flower is very scanty, the purpose of the study is to discover the therapeutic ability of the flowers of ten ethnomedicinal plants found in the southern Eastern Ghats of Tamil Nadu with a destination of providing cheaper nature-based alternative medicine. Flower extracts of ethnomedicinal plants, Abutilon indicum (L). Sweet, Calotropis gigantea (L.) W.T. Aiton, C. procera (Aiton), Catharanthus roseus (L.) G. Don., Martynia annua L., Memecylon umbellatum Burm.f., Ocimum tenuiflorum L. Ophiorrhiza mungos Linn., Scilla indica Baker. and Tecoma stans (L.) Kunth. were examined using agar well diffusion method against the human pathogens, Bacillus subtilis, Candida albicans, Klebsiella pneumoniae, Pseudomonas aeruginosa, Stephylococcus aureus and Streptococcus mutans. Flowers were extracted using 80% ethanol, phytochemical screening of these flowers were performed for constituents like, Carbohydrates, tannin, steroids, terpenoids, saponins, flavonoids, alkaloids, essential/volatile oil and glycosides. The Minimum Inhibitory Concentration (MIC) of selected three flower extracts against the pathogens also tested in contingent. From these finding revealed the medicinal potential of these flowers to cure the various infectious diseases. Compare to reference antibiotics, the spectrum of antimicrobial activity of flower extracts also found be clearly superior. The broad spectrum of antimicrobial activity of Martynia annua, Memecylon umbellatum and Calotropis gigantea may help to discover new chemical classes of antibiotics substances.
