The distribution of free sterols, polyhydroxysteroids and steroid glycosides in various body components of the starfish Patiria (= Asterina) pectinifera

The distribution of free sterols, polyhydroxysteroids and steroid glycoside s in different body components of the Far-eastern starfish Patiria (=Asteri na) pectinifera has been studied. It was shown that free sterol fractions f rom aboral and oral body walls, gonads, stomach and pyloric ceca contained Delta (7) sterols with a preponderance of 5 alpha -cholest-7-en-3 beta -ol. All these body components had also toxic steroid oligoglycosides. However, polyhydroxysteroids and related low molecular weight steroid glycosides we re found in stomach and pyloric ceca only. In pyloric ceca, the sulfated mo noside 'asterosaponin' P-1 was identified as a main polar steroid. whereas 6-sodium sulfate of cholestane-3 beta ,4 beta, 6 alpha ,7 alpha ,8,15 beta ,16 beta ,26-octaol predominated in the stomach. Probable biological functi ons of polar steroids and free sterols in this starfish were discussed. It was suggested that some polyhydroxysteroids and related monoglycosides play the same biological role as bile alcohols and bile acids do in vertebrates . (C) 2001 Elsevier Science Inc. All rights reserved.