Studies on the alpha-glucoside hydrolase inhibitor, adiposin. III. alpha Glucoside hydrolase inhibitory activity and antibacterial activity in vitro.

Adiposin-1 and -2 exhibited potent inhibitory activities against alpha-amylase, human salivary alpha-amylase and disaccharidases isolated from porcine small intestine. The effect of adiposin-1 and -2 on hydrolysis of glucoamylase was non-competitive. Adiposin showed antimicrobial activities against some Gram-positive bacteria, Gram-negative bacteria belonging to Enterobacteriaceae, Some anaerobic bacteria and some phytopathogenic fungi, and showed a synergistic effect on the antibacterial activity with some maltooligosaccharides. However, these antibacterial activities were suppressed by addition of various other saccharides.

Studies on the alpha-glucoside hydrolase inhibitor, adiposin. II. Taxonomic studies on the producing microorganism.

Streptomyces sp. TM-521 which produced alpha-glucoside hydrolase inhibitors, adiposins, was isolated from a soil sample collected in Hoya City, Tokyo. The strain belonged to the "gray color" series type of the ISP-classified Streptomyces. From the taxonomic studies, the strain TM-521 resembled with Streptomyces calvus in the morphological and physiological properties. This strain was accordingly identified as a strain of Streptomyces calvus.

Studies on the alpha-glucoside hydrolase inhibitor, adiposin. IV. Effect of adiposin on intestinal digestion of carbohydrates in experimental animals.

Adiposins showed a potent inhibitory activity against alpha-glucoside hydrolases such as salivary and pancreatic alpha-amylases, and intestinal disaccharidases in vivo. They suppressed the increase of the blood glucose level and the secretion of insulin in mice and rats which both had been fasted and then forced-fed on cooked corn starch, sucrose or maltose. The suppression of the increase in the body weight gains, and of the secretion of insulin and triglyceride in blood were observed in the experimental animals which were given diet containing adiposins. Hematological and histopathological examinations of animals treated with adiposins did not reveal any remarkable changes after a 3 months toxicity test. Adiposins did not show any intravenous acute toxicity in mice at dose levels (p.o.) less than 10 g/kg of body weight.

Triterpenoid Acids from Kadsura longipedunculata. Neokadsuranic Acids B and C: Two Novel Triterpenoids with 14 (13 --> 12)abeo-Lanostane Skeletons.

Six triterpenoid acids were isolated from the stems of KADSURA LONGIPEDUNCULATA, collected in Kuangxi province. Four of them were new compounds and assigned as (24 Z)-3-oxo-12alpha-acetoxylanosta-8,24-dien-26-oic acid ( 1), (24 Z)-3-oxo-12alpha-hydroxylanosta-8,24-dien-26-oic acid ( 2), (24 Z)-3-oxo-14(13-->12) ABEO-lanosta-8,13(18),24-trien-26-oic acid ( 3), and (24 Z)-3-oxo-13beta-hydroxy-14(13-->12) ABEO-lanosta-8,24-dien-26-oic acid ( 4). Compounds 3 and 4 were named neokadsuranic acids B and C, respectively.

Isolation and Structure Elucidation of Seco-neokadsuranic Acid A and 3,4-Seco-(24Z)-lanosta-4(30),8,24-triene-3,26-dioic Acid1.

Seco-neokadsuranic acid A, the second natural triterpenoid with the unusual 14(13-->12) ABEO-lanostane skeleton was isolated from KADSURA HETEROCLITA together with 3,4-seco-(24 Z)-lanosta-4(30),8,24,triene-3,26-dioic acid. The present paper deals with the isolation and structure elucidation of these two new compounds and the preparation of two new 7-oxo-lanostane triterpenoid derivatives.

Isolation and structure elucidation of 12beta-acetoxycoccinic Acid, 12beta-hydroxycoccinic Acid, 12alpha-acetoxycoccinic Acid, and 12alpha-hydroxycoccinic acid1.

Four new triterpenoid acids, possessing a lanost-9(11)-en-3-one skeleton, were isolated from KADSURA HETEROCLITA. Based on chemical and spectral analyses, they were assigned as 12beta-acetoxycoccinic acid, 12beta-hydroxycoccinic acid, 12alpha-acetoxycoccinic acid, and 12alpha-hydroxycoccinic acid.

Isolation and Structure Elucidation of Neokadsuranic Acid A, the First Triterpenoid with the 14 (13-->12) abeo Lanostane Skeleton, and (24Z)-3-Oxo-lanosta-8,24-dien-26-oic Acid1.

Neokadsuranic acid A, which is the first triterpenoid with the 14(13-->12) ABEO lanostane skeleton, was isolated from KADSURA HETEROCLITA together with (24 Z)-3-oxo-lanosta-8,24-dien-26-oic acid. The present paper deals with the isolation and structure elucidation of these two new compounds.