Oleaginous Red Yeasts: Concomitant Producers of Triacylglycerides and Carotenoids

Oleaginous Red Yeasts: Concomitant Producers of Triacylglycerides and Carotenoids: Comparison

Please note this is a comparison between Version 2 by Catherine Yang and Version 1 by David Levin.

Oleaginous red yeast species are colourful (usually having orange-pink-red hues) single cell microorganisms capable of producing valuable bioproducts including triacylglycerides (TAGs) for biodiesel and carotenoids for nutraceuticals. The name “oleaginous yeasts” is conferred based on their ability to synthesize and accumulate TAGs to over 20% of their dry cell weight. Their colours are indicative of the presence of the major carotenoids present in them.

oleaginous yeasts
red yeasts
carotenoids
neutral lipids
triacylglycerides
fatty acids
biodiesel

A goal of global net zero carbon emissions has been set for the year 2050, and continued research into renewable energy, such as biodiesel obtained from transesterification of triacylglycerols (TAGs), is important to achieving this goal. Oleaginous microorganisms are a viable source of TAGs. In addition to the production of neutral lipids (triacylglycerides, TAGs), some oleaginous microorganisms are brightly coloured, possessing the ability to concomitantly produce useful carotenoids.

Oleaginous red yeasts are capable of synthesizing and accumulating TAGs in excess of 20% of their dry cell weight ^[1]. In addition to production of biodiesel from the TAGs synthesized by oleaginous red yeasts, they can be used in the production of cocoa butter equivalent material ^[2] and polyunsaturated fatty acids (PUFAs), which are useful for nutritional and medical purposes ^[3]. Oleaginous red yeasts are classified in the subphylum Pucciniomycotina, and have orange to red to pink colorations due to the presence of various carotenoids, which are synthesized by the cells to prevent oxidation of the TAGs, and are important bioproducts in the nutraceutical and food industries.

Some genera under this group include Sporobolomyces, Sporidiobolus, Rhodotorula and Xanthophyllomyces ^[4]. These yeasts have several advantages over other sources, including their ease of culturing, high growth rate, the fast rate at which they synthesize and accumulate lipids and the low cost of the media needed for their growth ^[5], as well as their potential to grow on a plethora of substrates [6,7]^[6][7] and thrive under varied culture conditions ^[8]. The multi-functional application of these yeasts compels investigations into their molecular biology and metabolic pathways. Here, we examine the fatty acid biosynthesis and carotenoid pathways, their synchronization and gaps with emphasis on multi-omic studies.

References

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