Two novel amino oligosaccharides isolated from the culture of Streptomyces coelicoflavus ZG0656 as potent inhibitors of α-amylase

Two novel aminooligosaccharides were separated from the culture filtrate of Streptomyces coelicoflavus ZG0656. Their chemical structures were determined by electrospray ionization tandem mass spectrometry (ESI-MS/MS) and 2D nuclear magnetic resonance (NMR) spectroscopy. Because of their acarviosine core structures, the names acarviostatins II23 and II13 were given to the novel compounds. The two acarviostatins were both mixed noncompetitive inhibitors of porcine pancreatic alpha-amylase (PPA), with inhibition constants (K-i) of 0.009 mu M (acarviostatin II23) and 0.010 mu M (acarviostatin II13). Therefore, acarviostatin II23 and acarviostatin II13 are, respectively, 231 and 208 times more potent than acarbose. (c) 2007 Elsevier Ltd. All rights reserved.