Oscillatoxin I: A New Aplysiatoxin Derivative, from a Marine Cyanobacterium.

Hiroshi Nagai,Kaori Iida,Hajime Uchida,Shingo Sato,Kazutaka Hayashi,Mioko Kawaguchi,Masayuki Satake

doi:10.3390/toxins11060366

Abstract

Cyanobacteria have been shown to produce a number of bioactive compounds, including toxins. Some bioactive compounds obtained from a marine cyanobacterium Moorea producens (formerly Lyngbya majuscula) have been recognized as drug leads; one of these compounds is aplysiatoxin. We have isolated various aplysiatoxin derivatives from a M. producens sample obtained from the Okinawan coastal area. The frozen sample was extracted with organic solvents. The ethyl acetate layer was obtained from the crude extracts via liquid–liquid partitioning, then separated by HPLC using a reversed-phase column. Finally, 1.1 mg of the compound was isolated. The chemical structure of the isolated compound was elucidated with spectroscopic methods, using HR-MS and 1D and 2D NMR techniques, and was revealed to be oscillatoxin I, a new member of the aplysiatoxin family. Oscillatoxin I showed cytotoxicity against the L1210 mouse lymphoma cell line and diatom growth-inhibition activity against the marine diatom Nitzschia amabilis.

Highlights

The marine cyanobacterium Lyngbya majuscula is known to produce aplysiatoxins [1,2] and lyngbyatoxins [3,4], which cause severe contact dermatitis [1,3]
Blooms of L. majuscula have been increasing worldwide, threatening human health and eco-systems; this increase is presumably due to climate change [9]
We identified 15 aplysiatoxin derivatives in this Okinawan cyanobacteria sample [10]

Summary

Introduction

The marine cyanobacterium Lyngbya majuscula is known to produce aplysiatoxins [1,2] and lyngbyatoxins [3,4], which cause severe contact dermatitis [1,3]. Contact dermatitis due to L. majuscula has been reported in tropical and subtropical waters, especially in the Pacific region [5,6]. During the summer of 2010, a mass occurrence of Moorea producens (formerly L. majuscula) was observed in the Okinawa Prefecture and lasted for almost one month. A cyanobacterial sample collected at this site during the 2010 mass occurrence was used in this study. We identified 15 aplysiatoxin derivatives in this Okinawan cyanobacteria sample [10]. Aplysiatoxins have been shown to act as protein kinase C (PKC) activators and potent tumor promoting compounds [11,12,13,14,15]; their toxicity results

Methods

Results

Conclusion