Study On Flavonoid Components And The Inhibition On α-glucosidase Of Ethyl Acetate Fraction Partitioned From Dalbergia Odorifera T.Chen

Dalbergia odorifera (abbreviated as HDO), the dry heartwood of the Dalbergiaodorifera T. Chen trunks and roots. As a traditional Chinese medicine, it is widelyused in folk. According to the reports, the chemical constituents in HDO mainly arevolatile oils, phenols and flavonoids. The pharmacological activities of HDO havevasodilator, anticoagulant, anti-cancer, anti-inflammatory and so on. But there is nodomestic report about α-glucosidase inhibitory activity, and there is only a literatureon α-glucosidase inhibitory activity of HDO in other countries. In order to fill in theblank of domestic study in this field, and further provide scientific data supplementfor this activity of HDO. Study on chemical constituents and the inhibition onα-glucosidase of ethyl acetate fraction partitioned from HDO as follows:1. The flavonoids in HDO that had been reported were classified and summed upin this paper. Meanwhile, the research development of diabetes mellitus andhypoglycemic effect of flavonoids from medicinal plants were also summarized.2. In order to extract and isolate compounds from HDO, the ethyl acetate fractionwas obtained (HEF, the ethyl acetate fraction partitioned from the heartwood ofDalbergia odorifera). HEF was purified and separated by using the methods ofcolumn chromatography and recrystallization, and eight compounds were obtained.They were identified through UV, MS and NMR spectroscopy method. They were asfollows:(3R)-3’-O-methylviolanone,(3R)-Sativanone,(2S)-Pinocembrin,(2S)-Liquiritigenin,(2S)-4’,6-Dihydroxy-7-methoxylflavanone, Isoliquiritigenin,R(-)-Latifolin and7,3’-dihydroxy-5’-methoxyisoflavone. In addition, quantitativeanalysis of five compounds in HEF were firstly performed by using HPLC.3. The total extract of HDO and HEF on α-glucosidase inhibitory activity weretested in Vitro. The results showed that the total extract of HDO and HEF hadsignificant inhibition on α-glucosidase, and the α-glucosidase inhibitory activity ofHEF was better. The potential α-glucosidase inhibitors in HEF were screened by using ultrafiltration LC/MSn. The experiment found that there were18compoundsinteracted with α-glucosidase. According to the UV data and the auto MS2mode ofmass spectrometry data,16compounds were tentatively assigned. According to theseparation results,8compounds were unequivocally identified.4. Eight isolated compounds were estimated for their α-glucosidase inhibitoryactivity in vitro, and the results showed that (2S)-liquiritigenin,(2S)-4’,6-dihydroxy-7-methoxyflavanone and isoliquiritigenin had better inhibition of yeast α-glucosidasethan Acarbose (the drug of positive control).This study found that HEF and the components in it had obvious α-glucosidaseinhibitory activity in vitro. These results would provide important theory base forfurther development of natural α-glucosidase inhibitors (α-GI) with low toxicity andalso enrich the research content in literature of HDO.