Different light spectral qualities influence sterol pool in Porphyridium cruentum (Rhodophyta)

Abstract

Detailed sterol analysis of Porphyridium cruentum (Ag.) Nägeli, grown under different light spectral qualities, was carried out using TLC and GLC techniques. The total sterol amount along with the profile (22- dehydrocholesterol, cholesterol, brassicasterol, campesterol and cycloatenol) weights and their concentration inside different classes (free, steryl esters, steryl glycosides and acyl steryl glycosides) were determined. The results revealed a gradual decrease in the total sterol amount in the cells grown under different light spectral qualities according to the order: white>yellow> green>red>blue, however the composition of the sterol pool was not affected. Whatever the light conditions, cholesterol was the major component detected, mostly as steryl glycoside. Furthermore, our data demonstrated that the amount of different sterol profiles and their distribution among the free and conjugated forms strongly depend on the light spectral quality. © 2007 Academic Journals.