Sterols in microorganisms

Abstract

Sterols are vital components of all eukaryotic cells. This review describes the variety of sterol structures found in microalgae, yeasts, fungi, protozoans and microheterotrophs. Reports of the occurrence of sterols in prokaryotic cells are critically assessed. Methylotrophic bacteria contain unusual 4-methylsterols, but reports of 4-desmethyl sterols in cyanobacteria and other bacteria are limited and many of these seem dubious. Possible application areas for sterols derived from mass culture of microalgae and other microorganisms are highlighted.

Sources and preservation of sedimentary organic matter in the Southern Bohai Sea and the Yellow Sea: Evidence from lipid biomarkers

“…For all sediment samples, campesterol had minor amount with only constituted 1-4% of the total measured sterols. Brassicasterol was reported to be a more useful specific biomarker for some diatoms (Volkman, 2003;Hernandez et al, 2008). High concentrations of brassicasterol in sites from coastal areas support that the sediments in the coastal areas of Jiangsu Provinces and Shandong Provinces received more diatoms input (Table 1), which was in agreement with the observation from Di et al (2013) and Liu et al (2009).…”

“…However, Volkman (2003) and more recently Rampen et al (2009) showed that these compounds are also present in several groups of microalgae. Sitosterol was more abundant than stigmasterol, 125 ± 58 ng/g and 25 ± 13 ng/g, respectively in this study.…”

“…Sitosterol was more abundant than stigmasterol, 125 ± 58 ng/g and 25 ± 13 ng/g, respectively in this study. Gagosian et al (1983), Volkman (2003) MCalkanols: mid-chain alkanols (nC20OH-nC24OH).…”

Organic geochemical characteristics of black shales across the Ordovician–Silurian boundary in the Holy Cross Mountains, central Poland

“…Tricyclic compounds originated from algae and bacteria during the Ordovician (Moldowan et al, 1983;Ourisson et al, 1982;Zumberge, 1987). The relative abundance of regular steranes can be used as a biomarker indicator of contributing organisms and it has been suggested that the C 27 sterane is sourced from marine planktons while the C 29 sterane is derived from land plants (Huang and Meinschein, 1979;Volkman, 1986) or from microalgae (Volkman, 2003). As would be expected the ternary plot of steranes in the Ordovician samples reveals an abundance of C 27 steranes (Fig.…”

Acid catalysed backbone rearrangement of cholesta-2,4,6-triene: On the origin of ring A and ring B aromatic steroids in recent sediments

“…Yet, the most common D 5,7 -sterols (precursors of D 3,5,7 -steratrienes) possess 28 carbon atoms. Thus, ergosterol, a major C 28 D 5,7 -sterol common in most protozoa and fungi, is the most widespread D 5,7 -sterol (Nes and McKean, 1977;Patterson, 1994;Volkman, 2003; and references cited therein). As a result, sedimentary MAs and MBs will be enriched in C 28 members compared to other steroidal biomarkers.…”