Synthesis of acarbose transfer products by Bacillus stearothermophilus maltogenic amylase with simmondsin

Simmondsin, a material related to food intake inhibition from jojoba (Simmo ndsia chinensis), was transglycosylated by Bacillus stearothermophilus malt ogenic amylase (BSMA) reaction with acarbose to synthesize an antiobese com pound with hypoglycemic activity. Ten percent each of acarbose and simmonds in were mixed and incubated with BSMA at 55 degrees C. Glycosylation produc ts of simmondsin were observed by thin layer chromatography (TLC) and high performance ion chromatography (HPIC). The major transfer product was purif ied by using Biogel P-2 column. The structure was determined by matrix-assi sted laser desorption ionization with time of flight (MALDI-TOF)/mass spect rometry (MS) and C-13-NMR. The major transglycosylation product was pseudot risaccharide (PTS)-simmondsin, in which PTS was attached by an alpha-(1 --> 6) glycosidic linkage to simmondsin. The administration of transglycosylat ed simmondsin with acarbose (200 mg/kg per day for 6 days) significantly re duced the food intake by 74%, comparable to 62% of simmondsin versus contro l in ob/ob mice. The transfer product (10 mg/kg) significantly suppressed t he postprandial blood glucose response to starch (2 g/kg) by 68%, comparabl e to 60% of acarbose in Zucker fa/fa rats. The results indicated that the t ransfer products would be effective agents in lowering both food intake and blood glucose. (C) 2000 Elsevier Science B.V. All rights reserved.