Premium
EMPLOYMENT OF ORGANIC ACIDS TO ENHANCE ASTAXANTHIN FORMATION IN HETEROTROPHIC CHLORELLA ZOFINGIENSIS
Author(s) -
CHEN TAO,
WEI DONG,
CHEN GU,
WANG YAN,
CHEN FENG
Publication year - 2009
Publication title -
journal of food processing and preservation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.511
H-Index - 48
eISSN - 1745-4549
pISSN - 0145-8892
DOI - 10.1111/j.1745-4549.2009.00391.x
Subject(s) - astaxanthin , carotenoid , malic acid , chlorella , fermentation , haematococcus pluvialis , heterotroph , food science , chemistry , algae , biology , biochemistry , botany , bacteria , citric acid , genetics
The green alga Chlorella zofingiensis produces significant amounts of the valuable ketocarotenoid astaxanthin under heterotrophic growth conditions. In this study, pyruvate, citrate and malic acid were investigated, for the first time, to promote the formation of secondary carotenoids including astaxanthin in C. zofingiensis in the dark. The addition of pyruvate, citrate and malic acid into the culture medium at a concentration above 10 mM stimulated biosynthesis of astaxanthin and other secondary carotenoids. The addition of 100 mM pyruvate enhanced the yield of astaxanthin from 8.36 to 10.72 mg/L, representing an increase of 28.2%. Citrate and malic acid also had stimulatory effects on the formation of astaxanthin. The results showed that organic acid supplementation was potentially useful for commercial production of astaxanthin by C. zofingiensis in dark heterotrophic culture.PRACTICAL APPLICATIONS This article revealed, for the first time, that the organic acids including pyruvate, citrate and malic acid could enhance the production of secondary carotenoids including the highly valuable product astaxanthin in the green alga Chlorella zofingiensis using fermentation technology. This research contributed significantly to our understanding of the synthesis of astaxanthin in green algae in dark heterotrophic cultures which would facilitate scale‐up of the process to an industrial scale. In practice, organic acids could be used to effectively induce the formation of astaxanthin by C. zofingiensis during fermentation using organic carbon substrates as carbon sources, and at the same time to help adjust pH values favorably for astaxanthin production by C. zofingiensis in the fermenter.