In vitro biological activity of A. indica, C. limon and C. sinensis.

The spreading of resistance to antibiotics has fascinated the researcher to develop new antibiotics. However, it is predicted from history that new antimicrobials will have a short life. Thus, resistance to new drugs leads to a shortage of antimicrobials as the discovery of new antimicrobial drugs is not enough to cope with the fast emergence of resistant strains. This requires new potent antimicrobial compounds as an alternative to existing antibiotics. Phytochemicals having a low molecular weight, could be an alternative source of antimicrobials. Natural molecules are a more promising source of drugs. Natural molecules have a diverse chemical structure and biochemical specificity. Biologically active natural molecules usually have low molecular weight; they are easily absorbed and metabolized in the body. Major resources of natural molecules include plants, marine organisms and microbes. The plant produces innumerable secondary metabolites with several biological activities. Hence, it is worthwhile to explore the potential of plants for the development of new therapeutic agents.