RESUMO
Methanolic extracts of 18 Thai plants from Doi Tung, the north of Thailand, were examined for brine shrimp lethality and antioxidative activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. In brine shrimp lethality, the highly toxic plant extracts were Mitrephora wangii (LC(50) 14.8 µg mL(-1)) and Hydrocotyle javanica (LC(50) 13.3 µg mL(-1)). The extracts of Sageretia cordifolia, Ulmus lancaefolia and Acer chiangdaoense exhibited highly antioxidative activities with IC(50) values of 6.7, 8.1 and 9.8 µg mL(-1), respectively. Moreover, the extracts of S. cordifolia, U. lancaefolia and A. chiangdaoense have shown slightly synergistic effects (combination index; CI < 1) with L-ascorbic acid on DPPH radicals. A number of plants demonstrated either brine shrimp lethality or free radical scavenging activity.
Assuntos
Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Crustáceos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Animais , Antioxidantes/administração & dosagem , Ácido Ascórbico/administração & dosagem , Concentração Inibidora 50 , Extratos Vegetais/administração & dosagem , Tailândia , Testes de ToxicidadeRESUMO
Chemical constituents as well as cytotoxic and insecticidal activity of the crude methanol extract from the leaves of Phyllanthus reticulatus Poir. (Euphorbiaceae) were investigated. (5R*,6R*)-4,6-Dimethoxycarbonyl-5-[2',3',4'-trihydroxy-6'-(methoxycarbonyl) phenyl]-5,6-dihydro-2H-pyran-2-one (1) along with 3,4,3'-tri-O-methylellagic acid, and methyl gallate were isolated from the dichloromethane extract. Determination of their structures was based on spectroscopic analysis. Compound 1 possessed a very weak insecticidal activity against Spodoptera frugiperda (Sf9) with an IC(50) value of 27.27 microg/mL.
