Studies On The Chemical Constituents And Bioactivities Of Fruits Of Morus Alba L.

Fruits of Morus alba are belong to the genus Morus of Moraceae, which is used as not only a Traditional Chinese Medicine but also a kind of popular fruits. The bioactive screening on the95%ethanol extract of fruits of M. alba resulted in:the ethyl acetate fraction and n-Butanol fraction from95%ethanol displayed significant inhibitory activity against a-glucosidase.Various chromatographic methods are used to investigate the constituents of95%ethanol extract of the fruits of M. alba. The compounds were elucidated on the basis of spectroscopic analysis and chemical methods as well.Forty-six compounds were isolated from the fruits of M. alba, four compounds (1*-4*) are new compounds. These compounds were identified as:mulbaine A (1*), mulbaine B (2*), mulbaine C (3*),1-[5-(2-formlfuryl) methyl] dihydrogen-2-hydroxy-propane-1,2,3-tricarboxylate2,3-diethyl ester (4*),1-[2-(furan-2-yl)-2-oxoethyl] pyrroli-din-2-one (5), divaricataester A (6), methy1-[2-(furan-2-yl)-2-oxoethyl]-5-oxopyrrolidine-2-carboxylate (7),1-[2-(furan-2-yl)-2-oxoethyl]-5-oxopyrroidine-2-carboxylic acid (8), L-pyroglutamic acid (9). ethyl L-pyroglutamate (10).1.2-dihydro-2-oxoquindine-4-carboxylic acid (11),4-hydroxy-2-ethyl picolinate (12),4-methoxy-2-ethyl picolinate (13).6,7-dihydroxy coumarin (14),6-methoxy-7-hydroxy coumarin (15),7-hydroxy coumarin (16),5-hydroxymethyl furfural (17), p-hydroxy benzoic acid (18), gallic acid (19),3-methoxy-4-hydroxyl benzoic acid (20), p-hydroxy-cinnamic acid (21), ethy caffeic acid (22),4-hydroxy-5-(2-oxo-l-pyrrolidinyl)-benzoic acid (23), protocatec-hualdehyde (24),3,3’-diethyl ester citric acid (25),3-ethyoxyl-3’-methoxyl diethyl ester citric acid (26), β-sitosterol (27),β-daucosterol (28),3-O-caffeoylquinic acid methyl ester (29),3-O-caffeoylquinic acid ethyl ester (30),5-O-caffeoylquinic acid methyl ester (31),5-O-caffeoylquinic acid ethyl ester (32),4-O-caffeoylquinic acid methyl ester (33),4-O-caffeoylquinic acid ethyl ester (34),3-O-caffeoylquinic acid (35),4-O-caffeoylquinic acid (36),3-O-caffeoylquinic acid n-butyl ester (37),4-O-caffe--oylquinic acid n-butyl ester (38),5-O-caffeoylquinic acid n-butyl ester (39), rutin (40), quercetin-3-O-β-D-glucopyranoside (41), quercetin (42), quininic acid n-butyl ester (43), harman-3-carboxylic acid (44),2-(furan-2-yl)-5-(2,3,4-trihydroxybutyl)-1,4-diazine (45), cyclo-(Phe-Tyr)(46). Among them, compounds5-13,23,25,26,29-34,36-39,43-46were firstly isolated from fruits of M. alba.The results of the inhibition against a-glucosidase and aldose reductase showed that ethyl acetate fraction and n-butanol alcohol fraction of95%ethanol extract of fruits of M. alba had potent inhibitory activities. But the pure compounds isolated from fruits of M. alba had no inhbitory activities.