Dataset Information

Sequential phototrophic-mixotrophic cultivation of oleaginous microalga Graesiella sp. WBG-1 in a 1000 m² open raceway pond.

ABSTRACT:

Background

Microalgae are an important feedstock in industries. Currently, efforts are being made in the non-phototrophic cultivation of microalgae for biomass production. Studies have shown that mixotrophy is a more efficient process for producing algal biomass in comparison to phototrophic and heterotrophic cultures. However, cultivation of microalgae in pilot-scale open ponds in the presence of organic carbon substrates has not yet been developed. The problems are heterotrophic bacterial contamination and inefficient conversion of organic carbon.

Results

Laboratory investigation was combined with outdoor cultivation to find a culture condition that favors the growth of alga, but inhibits bacteria. A window period for mixotrophic cultivation of the alga Graesiella sp. WBG-1 was identified. Using this period, a new sequential phototrophic-mixotrophic cultivation (SPMC) method that enhances algal biomass productivity and limits bacteria contamination at the same time was established for microalgae cultivation in open raceway ponds. Graesiella sp. WBG-1 maximally produced 12.5 g biomass and 4.1 g lipids m^-2 day^-1 in SPMC in a 1000 m² raceway pond, which was an over 50% increase compared to phototrophic cultivation. The bacterial number in SPMC (2.97?×?10⁵ CFU ml^-1) is comparable to that of the phototrophic cultivations.

Conclusions

SPMC is an effective and feasible method to cultivate lipid-rich microalgae in open raceway ponds. Successful scale-up of SPMC in a commercial raceway pond (1000 m² culture area) was demonstrated for the first time. This method is attractive for global producers of not only lipid-rich microalgae biomass, but also astaxanthin and ?-carotene.

SUBMITTER: Wen X

PROVIDER: S-EPMC6371596 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Publications

Sequential phototrophic-mixotrophic cultivation of oleaginous microalga <i>Graesiella</i> sp. WBG-1 in a 1000 m<sup>2</sup> open raceway pond.

Wen Xiaobin X Tao Huanping H Peng Xinan X Wang Zhongjie Z Ding Yi Y Xu Yan Y Liang Lin L Du Kui K Zhang Aoqi A Liu Caixia C Geng Yahong Y Li Yeguang Y

Biotechnology for biofuels 20190211

<h4>Background</h4>Microalgae are an important feedstock in industries. Currently, efforts are being made in the non-phototrophic cultivation of microalgae for biomass production. Studies have shown that mixotrophy is a more efficient process for producing algal biomass in comparison to phototrophic and heterotrophic cultures. However, cultivation of microalgae in pilot-scale open ponds in the presence of organic carbon substrates has not yet been developed. The problems are heterotrophic bacter ...[more]

PMID: 30805027

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