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

Simmondsin, a material related to food intake inhibition from jojoba (Simmondsia chinensis), was transglycosylated by Bacillus stearothermophilus maltogenic amylase (BSMA) reaction with acarbose to synthesize an antiobese compound with hypoglycemic activity. Ten percent each of acarbose and simmondsin were mixed and incubated with BSMA at 55 degrees C. Glycosylation products of simmondsin were observed by thin layer chromatography (TLC) and high performance ion chromatography (HPIC). The major transfer product was purified by using Biogel P-2 column. The structure was determined by matrix-assisted laser desorption ionization with time of flight (MALDI-TOF)/mass spectrometry (MS) and C-13-NMR. The major transglycosylation product was pseudotrisaccharide (PTS)-simmondsin, in which PTS was attached by an alpha-(1 --> 6) glycosidic linkage to simmondsin. The administration of transglycosylated simmondsin with acarbose (200 mg/kg per day for 6 days) significantly reduced the food intake by 74%, comparable to 62% of simmondsin versus control in ob/ob mice. The transfer product (10 mg/kg) significantly suppressed the postprandial blood glucose response to starch (2 g/kg) by 68%, comparable to 60% of acarbose in Zucker fa/fa rats. The results indicated that the transfer products would be effective agents in lowering both food intake and blood glucose. (C) 2000 Elsevier Science B.V. All rights reserved.