Coral tumors store reduced level of lipids

The reef building coral Montipora informis (Scleractinia, Acroporidae) found on the colony surface of the fringing reef of Sesoko Island, Okinawa, Japan frequently carries hemispherical protuberances (tumors). We compared the total lipid content and the compositions of lipid and fatty acid between normal and tumorous tissues. The lipid content of tumor was 10.6% of the dry tissue weight, and was much lower than that for normal tissues (32.2%). The decrease in the total lipid content of tumorous tissue accompanied a reduced proportion of wax and triacylglycerol (TG). The major fatty acid component was 16:0 (palmitic) acid, and comprised comparable proportion of polar lipids and free fatty acid from both tumorous and normal tissues. An increasing tendency of polyunsaturated fatty acid (PUFA; C > 20) was noted in the free fatty acid and polar lipid fractions from tumorous tissues compared with the normal tissue. Thus, the present study first demonstrated the reduced lipid storage level in the tumorous coral, and discussed the rationale for these observations. (C) 2001 Elsevier Science B,V. All rights reserved.