Antibiotics are one of the most important weapons in fighting bacterial infections and have greatly benefited the health related quality of human life since their introduction. However, over the past few decades, these health benefits are under threat as many commonly used antibiotics have become less effective against certain illnesses not only because many of them produce toxic reactions, but also due to emergence of drug resistant bacteria. Drugs derived from natural sources play a significant role in the prevention and treatment of human diseases. Infectious diseases are the second leading cause of death world-wide.[
1] In industrialized nations, despite the progress made in the understanding of microbiology and their control, incidents of epidemics due to drug resistant microorganisms and the emergence of hitherto unknown disease–causing microbes, pose enormous public health concerns.[
2] The emergence of multidrug–resistant bacteria has created a situation in which there are few or no treatment options for infections with certain microorganisms.[
3] Along with bacterial infections, the fungal infections also are a significant cause of morbidity and mortality despite advances in medicine and the emergence of new antifungal agents.[
4]
Although the need for new antimicrobials is increasing, development of such agents faces significant obstacles.[
5] A number of factors make antimicrobial agents less economically attractive targets for development than other drug classes.[
6] Pharmaceutical research and development costs which are estimated to be $400–$800 million per approved agent,[
7] pose a considerable barrier to new drug development in general. Plants generally produce many secondary metabolites which constitute an important source of microbicides, pesticides, and many pharmaceutical drugs. Plant products still remain the principal source of pharmaceutical agents used in traditional medicine.[
8,
9] The effects of plant extracts on bacteria have been studied by a very large number of researchers in different parts of the plant.[
10,
11] Historically, plants have provided a good source of anti–infective agents; emetine, quinine, and berberine remain highly effective instruments in the fight against microbial infections. Phytomedicines have shown great promise in the treatment of intractable infectious diseases including opportunistic HIV infections. Plants containing protoberberines and related alkaloids, picralima–type indole alkaloids, and garciniabiflavonones used in traditional African system of medicine, have been found to be active against a wide variety of micro-organisms.[
12] Many plants have been reported to have antifungal activity.[
13,
14]
Cordia dichotoma Linn. (Boraginaceae) is tree of tropical and subtropical regions, commonly known as Lasura in Hindi and
Shlesmataka in Sanskrit. It is a medium sized tree with short crooked trunk, leaves simple, entire and slightly dentate, elliptical–lanceolate to broad ovate with round and cordate base, flower white, fruit drupe, yellowish brown, pink or nearly black when ripe with viscid sweetish transparent pulp surrounding a central stony part.[
15] It grows in sub-Himalayan tract and outer ranges, ascending up to about 1500 m elevation.[
16] It is used as immunomodulator, antidiabetic, anthelminitic, diuretic and hepatoprotective in folklore medicine. Seeds have disclosed the presence of α–Amyrin, betulin, octacosanol, lupeol–3–rhamnoside, β–sitosterol, β–sitosterol–3–glucoside, hentricontanol, hentricontanol, taxifolin–3,5–dirhmnoside, and hesperitin–7–rhamnoside.[
17] Preliminary phytochemical analysis of
C. dichotoma bark indicated the presence of relatively high levels of alkaloids, flavonoides, steroids, and terpenoids. Hence, the present investigation was undertaken to determine the antioxidant potential of
C. dichotoma bark.