Evaluation of flavonoid contents from three selected medicinal tree species growing in Sikar district of Rajasthan like Ailanthus excelsa, Pongamia pinnata and Salvadora oleoides was carried out. The leavesa and fruits of selected trees collected from study area were analysed for flavonoid contents i.e. Quercetin and Kaempferol. These flavonoid contents were isolated and identified. The maximum total flavonoid contents (1.82 mg./g.d.w) were found in leaves of Pongamia pinnata while minimum (0.86 mg./g.d.w) in fruits of Ailanthus excelsa.
An ornamental plant Euphorbia milii (Euphorbiaceae) is plays a role in folk medicine. The Chinese use it as a cure for cancer, and some Brazilians believe that it can cure warts. Phytochemical studies showed the presence of cardiac glycosides, steroids/phytosterols, anthocyanin, terpenoids, flavonoids and tannins.The Antimicrobial activity studies of hexane, ethyl acetate,chloform,petroleum ether,and water extracts of flowers of Euphorbia milii were performed on gram positive organisms(Bacillus subtilis, Bacillus megaterium,Staphylococcus aureus, Entrococci ) and gram negative organisms (Escherichia coli and Proteus vulgaris, Pusodomonas aeruginosa) by using cup plate method. The hexane extracts in the concentration of 5μg/ml, have shown considerable inhibition zone on as compared to other extracts.Bacillus subtlis and Bacillus megaterium have not show inhibition zone from solvent extract which was compared with the inhibition zone produced by standard amikacin sulphate (1μg/ml.).