Seasonal Variation of Sterol, Hydrocarbon, and Fatty Acid Fractions in Cladophora densa HARVEY

Abstract

The present paper describes the seasonal variation of constituents such as sterol, hydrocarbon, and higher fatty acid fractions from Cladophora densa HARVEY growing profusely in the Seto Inland Sea of Japan.
C. densa HARVEY is characterized by a high content of β-sitosterol [(24R)-24-ethyl-5-cholesten-3β-ol] as the major component in the sterol fraction throughout the year. This content rapidly increased to its maximum level in the autumn months (growth season) and then gradually decreased to its minimum level during the winter months (decay season). The contents of campesterol [(24R)-24-methyl-5-cholesten-3β-ol] and cholesterol were consistently low in all seasons.
cis-7-Heptadecene was characteristically present in appreciable amounts throughout the year. The C₁₈-unsaturated fatty acids were the major components in the higher fatty acid fraction in almost all seasons, except for the early autumn months when such contents decreased to the minimum levels.