Using various chromatographic separations, six steroid glycoside derivatives, including one new compound named culcinoside E (1), were isolated from the methanol extract of the starfish Culcita novaeguineae. Their structures were confirmed by detailed analysis of the 1D, 2D NMR, and HR ESI QTOF mass spectra. Among isolated compounds, culcinoside E (1), diplasterioside A (5), and thornasteroside A (6) inhibited growth of Enterococcus faecalis, whereas culcitoside C1 (3) was active on Candida albicans.
Keywords: Asteroidea; Asterosaponins; Culcita novaeguineae; antimicrobial activity; culcinoside E; steroidal biglycoside.