not available Dhaka Univ. J. Pharm. Sci. 17(2): 265-267, 2018 (December)

Three fractions obtained by Kupchan partitioning of 70% methanol extract of leaves of Stevia rebaudiana with n-hexane, dichloromethane and ethyl acetate designated by HSR, DSR and ESR were investigated for their antioxidant and antimicrobial activities. HSR and ESR exhibited prominent free radical scavenging activity having IC50 value of 11.59 and 10.38 μg/ml compared to standard, ascorbic acid (IC50 value 6.05 μg/ml). HSR and ESR also demonstrated significant antibacterial activity by disc diffusion method on some Gram-positive and Gramnegative bacteria. Among the fractions ESR showed the highest antioxidant and antibacterial activity. No significant antifungal activity was observed for any fraction. Preliminary phytochemical screening of all fractions showed the presence of alkaloids, saponin, flavonoids, tannin, carbohydrate and triterpenoids. Total three compounds have been isolated from ESR fraction among which two known compounds (1-2) were characterized as quercitrin (1) and physcion (2) through 1D NMR spectroscopic technique and other one could be a 9,10- anthraquinone derivative which was not characterized yet. The compound physcion (2) is first time report from the plant Stevia rebaudiana. Dhaka Univ. J. Pharm. Sci. 19(2): 191-197, 2020 (December)

Four cycloartane type triterpenoids and three stigmastane type steroids were isolated from the methanolic extract of stem and root part of Pothos scandens L. (Araceae), a Bangladeshi medicinal plant by high performance liquid chromatographic technique. The compounds were characterized as 24-methylenecycloartanol (1), 24-methylenecycloartenone (2), 24-en-cycloartenone (3), 24-methylenecycloartanyl ferulate (4), stigmast-4-en-3-one (5), stigmast-4,22-diene-3-one (6) and β-sitosterol glucoside (7) through extensive 1D and 2D NMR spectroscopic studies. All the isolates were evaluated for their estrogenic/antiestrogenic activity using the estrogen-responsive breast cancer cell lines, MCF-7 and T47D. The results showed that all the compounds possess mild to strong antiestrogenic activity in both cell lines which was compared to positive control tamoxifen. 24- Methylenecycloartanol (1), which contains a hydroxyl group in its C-3 position, inhibited 90% of estradiol (E2)- induced cell proliferation in MCF-7 and T47D cell lines at a concentration of 0.01 μM only. 24- Methylenecycloartanyl ferulate (4) and stigmast-4,22-diene-3-one (6) showed 90% of estradiol (E2)-induced cell proliferation in T47D cell only at a concentration of 0.01 μM whereas 10.0 μM was required for 24- methylenecycloartanyl ferulate (4) for the same activity in MCF-7 cells. This is the first report of isolation of these compounds from the plant along with their antiestrogenic property. Dhaka Univ. J. Pharm. Sci. 18(1): 93-102, 2019 (June)

No abstract

not availablePhilosophy and Progress, Vol#53-54; No#1-2; Jan-Dec 2013;