RESUMO
Phyllodiumpulchellum has been traditionally used as a medicinal herb because of its health-promoting effects, such as its hepatoprotective and antioxidant activities. In the present study, the petroleum ether fraction, ethyl acetate fraction, n-butanol fraction, and aqueous fraction were successively obtained from the ethanol extract of P. pulchellum. Two fractions, ethyl acetate fraction and n-butanol fraction, were found to display hepatoprotective and antioxidant activities. Further chemical investigation of the active fractions led to the isolation of its main constituents, including 11 flavonoids (1â»11) and 8 indole alkaloids (12â»19). There were 9 flavonoids (1â»9) that were obtained from the ethyl acetate fraction, and 2 flavonoids (10 and 11) and 8 alkaloids (12â»19) from the n-butanol fraction. Compounds 1â»11 and 16â»19 were isolated for the first time from P. pulchellum, and 1, 2, 8, 11, and 18 were obtained from the genus Phyllodium initially. Subsequently, the isolated compounds were evaluated for their in vitro hepatoprotective effects on the human normal hepatocyte cell line L-O2 injured by d-galactosamine and radical scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH). The flavonoids (-)-epigallocatechin (5) and (-)-epicatechin (6) exhibited prominent hepatoprotective activities with higher cell viability values (65.53% and 62.40% at 10 µM·mL-1, respectively) than the positive control, silymarin (61.85% at 10 µM·mL-1). In addition, compared with the positive control of vitamin C (IC50: 5.14 µg·mL-1), (-)-gallocatechin (3) and (-)-epigallocatechin (5) exhibited stronger antioxidant activities with IC50 values of 3.80 and 3.97 µg·mL-1, respectively. Furthermore, the total flavonoids from P. pulchellum were characterized using a high-performance liquid chromatography-linear ion trap quadrupole-Orbitrap-mass spectrometry (HPLC-LTQ-Orbitrap-MS). In total, 34 flavonoids were tentatively identified, which had not been previously reported from P. pulchellum. In addition, we performed a semi-quantitative analysis of the isolated flavonoids. The contents of compounds 1â»11 were 3.88, 17.73, 140.35, 41.93, 27.80, 4.34, 0.01, 0.20, 9.67, 795.85, and 5.23 µg·g-1, respectively. In conclusion, this study revealed that the flavonoids that were isolated from P. pulchellum showed hepatoprotective and antioxidant activities, indicating that, besides alkaloids, the flavonoids should be the potential pharmacodynamic ingredients that are responsible for the hepatoprotective and antioxidant activities of P. pulchellum.
Assuntos
Antioxidantes/farmacologia , Fabaceae/química , Fígado/efeitos dos fármacos , Antioxidantes/química , Linhagem Celular , Cromatografia Líquida de Alta Pressão/métodos , Hepatócitos/efeitos dos fármacos , Humanos , Espectrometria de Massas/métodos , Relação Estrutura-AtividadeRESUMO
AIM To study the chemical constituents from Phyllodium pulchellum (L.) Desv..METHODS The ethyl acetate and n-butanol fractions of P.pulchellum 95% ethanol extract were isolated and purified by Sephadex LH-20,silica,ODS and pre-HPLC column,then the structures of isolated compounds were identified by physicochemical properties and spectral data.RESULTS Eleven compounds were isolated and identified as phydroxybenzoic acid (1),protocatechuic acid (2),protocaechuic acid methyl ester (3),protocatechuic acid ethyl ester (4),ethyl gallate (5),p-coumaric acid (6),caffeic acid ester (7),loliolide (8),uridine (9),arbutin (10),daucosterol (11).CONCLUSION Compounds 4-11 are isolated from genus Phyllodium for the first time,compounds 2 and 3 are first obtained from this plant.
RESUMO
Three new phenolic constituents 1-3 were obtained from the 95% ethanol extract of the roots of Phyllodium pulchellum (Leguminosae). Their structures were elucidated on the basis of spectroscopic analyses, such as NMR, UV, IR, HR-ESI-MS, and CD. Furthermore, in an in vitro bioassay, all compounds were tested for inhibitory effects against the proliferation of acetaldehyde-stimulated HSC-T6 cells, and compound 3 exhibited potent inhibitory activity with the IC50 value of 7.6 µM.