Isolation, Structure Elucidation, and Biological Activity of the Steroid Oligoglycosides and Polyhydroxysteroids from the Antarctic StarfishAcodontaster conspicuus

Abstract

A total of 19 steroids, of which 13 steroidal oligoglycosides (nine new and four known) and six polyhydroxylated steroids (four new and two known), has been isolated from the Antarctic starfish Acodontaster conspicuus. The mixture is dominated by glycosides composed of steroidal aglycons having the hydroxyl groups typically disposed on one side of the tetracyclic nucleus, i.e., 3 beta,4 beta,6 alpha,8,15 beta-, with some having a sulfate at C-6, and differing in the side chains and/or in the disaccharide moieties that are usually attached at C-26, with some at C-28 and C-29. Those compounds are accompanied by minute amounts of glycosides with a delta 8(14)-double bond in the steroid, which is a structural feature not previously found among polyhydroxysteroids derived from starfish. Small amounts of six related unglycosidated polyhydroxysteroids and three higher-molecular-weight asterosaponins complete the composition of the mixture. The structures of the new compounds were determined by interpretation of their spectral data and by comparison with spectral data of known compounds. Eighteen of these compounds were evaluated for their ability to inhibit growth in Antarctic marine bacteria isolated from either the water column or the surfaces of benthic marine invertebrates. Of these compounds, 50% were active against at least one Antarctic marine bacterium. This suggests that these compounds may play an important role in deterring microbial fouling.

Chemical Constituents and Bioactivities of Starfish

“…Most of them are endowed with a 6a-OH group, are sometimes 6a-O-sulfonylated, and rarely 6a-Ophosphorylated. Mostly, C(4), C(5), C(8), C(15), C (16), and C (17) are not substituted. The sulfonylated steroid 10 was isolated from both Leptasterias alaskensis asiatica and L. fisheri, starfish collected at the Kiril Islands [7].…”

Chemical Interactions in Antarctic Marine Benthic Ecosystems

“…We evaluated the antibacterial activity of different extracts using the methods described in the literature with Antarctic bacteria (e.g. Jayatilake et al, 1996;De Marino et al, 1997, Mahon et al, 2003. Selected bacteria from the sea water were collected during the campaign, cultured on marine agar Difco brand (DMA 2216), and later sent to specialists for further identification.…”

Aphicidal Activity of Starfish (Asterina pectinifera) Extracts against Green Peach Aphid (Myzus Persicae)

“…불가 사리 생물체는 스테로이드 외에 글리코겐 화합물, 퀴논계 화 합물, 알칼로이드 화합물, 당지질성 화합물, 인지질 등의 다양 한 생체물질로 구성되어 있어 의약 및 농업소재로서 활용 가 치가 높다고 알려져 있다 (Palagiano et al, 1995;de Marino et al, 1997;Choi et al, 2010). 우리나라 근해저에 서도 수산양식장에 막대한 피해를 주고 있는 해적생물인 불 가사리가 대량 번식하고 있는 실정으로서 이에 대한 대책마 련이 시급한 실정이나 불가사리의 주요 성분인 칼슘 성분을 이용한 사료 또는 비료 첨가제로서의 활용에 그치고 있다 (Lee et al, 1989 불가사리 추출물의 진딧물 살충기작을 조사하기 위해 추 출물이 처리된 진딧물을 투과전과현미경을 이용하여 분석하 였다 (Fig.…”