Abstract

D'ARMAS, Haydelba Trinidad; RODRIGUEZ, Fátima  and  SALAZAR, José. Preliminary phytichemical study and bioactivity of the plant Melochia Villosa from Amazonas State, Venezuela. Saber [online]. 2013, vol.25, n.4, pp.382-389. ISSN 1315-0162.

A preliminary phytochemical analysis was conducted of crude extracts of stem, leaves and flowers of Melochia villosa (Plantae: Sterculiaceae), collected in Puerto Ayacucho, Amazonas state, Venezuela, and antimicrobial activitytest and lethality test against Artemia salina were applied. Phytochemical tests showed the presence of unsaturated sterols and pentacyclic triterpenes in all extracts, with the exception of the alcoholic extract of the leaves (EALH), flavonoids only in the alcoholic extracts, and phenylpropanoids in the alcoholic extracts of the leaves and stem (EALT). The stem ether extract (EET) showed mild antibacterial activity (halo of 7 mm) against Staphylococcus aureus, whereas the ether extract of flowers (EEF) was active against the same strain (halo of 9 mm) besides of showing slight activity against Micrococcus luteus (halo of 8 mm), and moderate against Enterobacter cloacae and Bacillus subtilis (halo of 10 mm). The EALH was active against Escherichia coli, Acinetobacter calcoaceticus, Bacillus subtilis, Staphylococcus aureus and Pseudomonas aeruginosa. Only EALT showed slightly antifungal activity against Fusarium poae strain. The EET exhibited excellent lethal activity showing a mean lethal concentration (LC50) of 2.06 μg /mL, followed by the EEF and EALT with a LC50 of 10.00 μg /mL for both; the EALH had a LC50 of 74.68 μg/mL and the leaves ether extract a LC50 of 169.10 μg/mL. These results allows to infer that this plant is a promising source of bioactive secondary metabolites.

Keywords : Sterculiaceae; antimicrobial activity; lethality; secondary metabolites.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )