Brown algae classification

A review of their biological activity. Phycologia 42 332-350 Wehr JD (2003) Brown algae. In Wehr JD, Sheath RG (eds) Freshwater algae of North America ecology and classification. Academic, San Diego, CA, pp 757-773 Whitton BA, Potts M (2000) The ecology of cyanobacteria their diversity in time and space. Kluwer Academic, Netherlands. 

The structure of the sex pheromone for the Fucus species, fucoserratene (11), was elucidated in 1973.16 The positions and geometries of alkenes were revealed by comparison of the gas chromatographic behavior with those of the isomeric conjugated 1,3,5- and 2,4,6-octatrienes. To date, a series of hydrocarbons and epoxides 1-11 and their stereoisomers have been identified within the pheromone bouquets of more than 100 different species of brown algae.17-23 Identification of these compounds was based on a combination of gas chromatography-mass spectrometry (GC-MS) analysis and by comparison with authentic synthetic compounds. These sex pheromones were all lipophilic, volatile compounds that consisted of C8 or Cn linear or monocyclic hydrocarbons or their epoxides. The monocyclic compounds have a cyclopropane, cyclopentene, or cyclo-heptadiene structure. Interestingly, the relationships between the chemical structures of pheromones and the taxonomical classifications of algae are unclear (Table 1). 

The recent classification of brown algae of De Reviers and Rousseau is also discussed in more detail in De Reviers (2003). The order Ectocarpales includes former orders of Chordariales, Dictyosiphonales, Punctariales and Scytosiphonales. The number of families (49) should be supplemented by two new families in the order Fucales, and a new family in the order Scytothamnales. Nine other families are still considered Incertae sedis. 

Thraustochytrids contain astaxanthin, which is the reason for their classification among the Chromista (or chromists), such as diatoms and brown algae (Cavalier-Smith, 1993 Cavalier-Smith, Allsopp, and Chao, 1994), but the recent interest in this group of microheterotrophs is due to their often very high contents of long-chain polyunsaturated fatty acids usually characterized by doco-sahexaenoic acid (DHA), which explains their importance in current biotechnological research. Another potential... 

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