ABSTRACT
Objective: To study the chemical constituents of Empetrum nigrum var. japonicum. Methods: The chemical constituents were isolated by silica gel column chromatography and HPLC, and its structure was identified by their spectral data and physicochemical properties analysis. Results: Twenty-two compounds were isolated from ethyl acetate extracts of E. nigrum var. japonicum with the structures identified as 3,4-dihydroxybenzoic acid (1), 3-methoxy-4-hydroxybenzoic acid (2), methyl-3,4-dihydroxybenzoate (3), dihydroconiferyl alcohol (4), (6S,9R)-vomifoliol (5), (6R,9R)-9-hydroxy-3-one-α-ionol (6), phenylpropionic acid (7) quercetin-3-O-(6″-benzoyl)-β-D-galactoside (8), daucosterol (9), quercetin-3-O-β-D-glucopyranoside (10), phenylpropyl-O-β-D-glucopyranoside (11), maslinic acid (12), rutinum (13), quercetin-3-O-β-D-galactoside (14), benzyl-(6-O- α-L-arabinofuranosyl)-O-β-D-glucopyranoside (15), cinnamol-O-(6-O-α-L-arabinopyranosyl)-β-D-glucopyranoside (16), quercetin-3- O-neohesperidoside (17), kaempferol-3-O-neohesperidoside (18), 2α,3β-dihydroxyurs-12-en- 28-oic acid (19), foliachinenoside A2 (20), kaempferol-3-O-rutinoside (21) and isorhamnetin-3-O-rutinoside (22). Conclusion: Compounds 1-6, 8, 11-13, 15-22 were isolated from E. nigrum var. japonicum for the first time.
ABSTRACT
Objective: To study the optimum extraction conditions of flavonoids from the leaves of Hibiscus mutabilis L. Methods: The orthogonal design L 9(3 4) was used. The 70% alcohol refluent method was compared with the decoction or 75% alcohol warm infusion process. Results: The 70% alcohol reflux was the best method.Conclusion: A 1B 3C 3D 3 is the best extraction condition of flavonoids from the leaves of Hibiscus mutabilis L..
