Simultaneous improvement in production of microalgal biodiesel and high-value alpha-linolenic acid by a single regulator acetylcholine

Abstract

BackgroundPhotoautotrophic microalgae are a promising avenue for sustained biodiesel production, but are compromised by low yields of biomass and lipids at present. We are developing a chemical approach to improve microalgal accumulation of feedstock lipids as well as high-value alpha-linolenic acid which in turn might provide a driving force for biodiesel production.ResultsWe demonstrate the effectiveness of the small bioactive molecule “acetylcholine” on accumulation of biomass, total lipids, and alpha-linolenic acid in Chlorella sorokiniana. The effectiveness exists in different species of Chlorella. Moreover, the precursor and analogs of acetylcholine display increased effectiveness at higher applied doses, with maximal increases by 126, 80, and 60% over controls for biomass, total lipids, and alpha-linolenic acid, respectively. Production of calculated biodiesel was also improved by the precursor and analogs of acetylcholine. The biodiesel quality affected by changes in microalgal fatty acid composition was addressed.ConclusionThe chemical approach described here could improve the lipid yield and biodiesel production of photoautotrophic microalgae if combined with current genetic approaches.Electronic supplementary materialThe online version of this article (doi:10.1186/s13068-015-0196-0) contains supplementary material, which is available to authorized users.

Elevated CO2 improves lipid accumulation by increasing carbon metabolism in Chlorella sorokiniana

“…Finally, the lipid contents (mg/g of dry weight) were obtained at 3 days after the stationary phase. Lipid extraction was performed as previously described (Parsaeimehr et al ., ).…”

Mitigating effects of acetylcholine supply on soybean seed germination under osmotic stress

“…However, Mukherjee (1980) tested higher concentrations of Ach in soybean seed germination, observing a stimulating effect on the elongation of hypocotyls. Parsaeimehr et al (2015) observed that an exogenous application of 5 lg L -1 of Ach in Chlorella sorokiniana has a stimulatory role in the growth and accumulation of lipids. On the other hand, in Vigna sesquipedalis, there was suppression in the growth of hypocotyl and, simultaneously, there was an increase in epicotyl (Hoshino 1983).…”

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