eng Science and Education Publishing Biomedicine and Biotechnology 2013-12-12 1 2 21 26 10.12691/bb-1-2-5 BB2013125 article Suraj Raj Adhikari adhikarisr@gmail.com 1 Bijaya Pant 1 Kusum Pokhrel 1 Central Department of Botany, Tribhuvan University, Nepal Withania somnifera is an important medicinal plant and a major source of alkaloids and steroids. Large callus was obtained from stem explants in MS medium with additives of 0.5 mgL1 6-Benzylaminopurine (BAP) + 1.5 mgL-1 α-Napthalene acetic acid (NAA). In phytochemical screening of in vivo and in vitro materials of W. somnifera; reducing compounds, cardiac glycosides, basic alkaloids, carotenoids, volatile oils and saponins were detected. Phytochemical compounds found in callus of W. somnifera stopped the growth of bacteria Pseudomonas aeruginosa, Proteus vulgaris and Klebsicela pneumonia more effectively than the compounds found in its natural root. Whereas active phytochemical compound found in natural root was more effective to stop the growth of bacteria Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Salmonella typhimurium. From this study it can be predicted that specific compounds which is not found in roots of naturally growing plants plant be found in the callus of W. somnifera. http://pubs.sciepub.com/bb/1/2/5/bb-1-2-5.pdf in vivoin vitroWithania somniferaPseudomonas aeruginosaProteus vulgarisKlebsicela pneumoniaEscherichia coliStaphylococcus aureusBacillus subtilisSalmonella typhimurium