Nitrogen Feeding Strategies and Metabolomic Analysis To Alleviate High-Nitrogen Inhibition on Docosahexaenoic Acid Production in Crypthecodinium cohnii.
J Agric Food Chem
; 66(40): 10640-10650, 2018 Oct 10.
Article
em En
| MEDLINE
| ID: mdl-30226986
ABSTRACT
It is well-known that high-nitrogen content inhibits cell growth and docosahexaenoic acid (DHA) biosynthesis in heterotrophic microalgae Crypthecodinium cohnii. In this study, two nitrogen feeding strategies, pulse-feeding and continuous-feeding, were evaluated to alleviate high-nitrogen inhibition effects on C. cohnii. The results showed that continuous-feeding with a medium solution containing 50% ( w/v) yeast extract at 2.1 mL/h during 12-96 h was the optimal nitrogen feeding strategy for the fermentation process, when glucose concentration was maintained at 15-27 g/L during the same period. With the optimized strategy, 71.2 g/L of dry cell weight and DHA productivity of 57.1 mg/L/h were achieved. In addition, metabolomic analysis was applied to determine the metabolic changes during different nitrogen feeding conditions, and the changes in amino acids, polysaccharides, purines, and pentose phosphate pathway were observed, providing valuable metabolite-level information for exploring the mechanism of the high-nitrogen inhibition effect and further improving DHA productivity in C. cohnii.
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Base de dados:
MEDLINE
Assunto principal:
Dinoflagellida
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Ácidos Docosa-Hexaenoicos
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Microalgas
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Nitrogênio
Idioma:
En
Ano de publicação:
2018
Tipo de documento:
Article