Analysis Of Chemical Constitutions Of DPP-IV Inhibitory Components From Fermentation Product Of Inonotus Obliquus

Dipeptidyl peptidase IV (DPP-IV) was one of the treatment target for diabetes. Theresearch focous on the screening of DPP-IV inhibitors from natural products. Fuscoporiaoblique was a traditional medical and edible fungi. It had been used for the treatment ofdiabetes. In our previous study, the DPP-IV inhibitory activity of chloroform extract offermentation product from Fuscoporia oblique was confirmed, while the single compounds ofchloroform extract was not separated.The submerged fermentation technology and solvent extraction were used to obtain thefermentation product from Fuscoporia oblique and its chloroform extract in this paper.Column chromatographic techniques were used for the isolation and purification ofchloroform extract. The structures of the single compounds were identified by spectral data.These compounds activity were evaluated by the model of DPP-IV inhibitory activity in vitro.The main conclusions of the paper were as follows:(1)379.39g of fermentation product from Fuscoporia oblique was obtained byfermentation method.4.94g chloroform extract was obtained by solvent extraction technique.Chloroform extract was separated by silica column chromatography, and Fr.I640mg, Fr.II176mg and Fr.III301mg were isolated respectively.(2)8compounds were isolated from the Fr.II and Fr.III by HPLC, and the structures of6compounds were identified by spectral data. I and VIII were Macrophorin A, II was4-[(5,5,8a-trimethyl-2-methylene-1-naphthylenyl) methyl]-2,5-dihydroxybenzaldehyde, III was4’-oxomacrophorin A, IV was ergosterol, VI was (12Z,15Z)-9,10-dihydroxyoctadeca-12,15-dienoic acid. Besides, I, II, III and VI were isolated from Fuscoporia oblique for the firsttime, and VI was isolated from natural products for the first time.(3) The model of DPP-IV inhibitory activity in vitro was applied for the evaluation of the8compounds. The IC50of I, II, IV and V were26.53mg·L-1,30.78mg·L-1,10.25mg·L-1and21.49mg·L-1respectively. The IC50of the5compounds were higher than that of chloroformextract (IC5080.23mg·L-1).(4) The component of Fr.I had been screened preliminarily by molecular docking, andthe result showed that3compounds (Ethyliso-allocholate, Deoxysperguain and25,26-Dihydroxyvitamin D) had good affinity to DPP-IV.