Sustainable mixotrophic microalgae refinery of astaxanthin and lipid from Chlorella zofingiensis

Vaibhav Sunil Tambat; Anil Kumar Patel; Reeta Rani Singhania; Akash Pralhad Vadrale; Archana Tiwari; Chiu-Wen Chen; Cheng-Di Dong

doi:10.1016/j.biortech.2023.129635

Sustainable mixotrophic microalgae refinery of astaxanthin and lipid from Chlorella zofingiensis

Bioresour Technol. 2023 Nov:387:129635. doi: 10.1016/j.biortech.2023.129635. Epub 2023 Aug 5.

Authors

Vaibhav Sunil Tambat¹, Anil Kumar Patel², Reeta Rani Singhania², Akash Pralhad Vadrale¹, Archana Tiwari³, Chiu-Wen Chen⁴, Cheng-Di Dong⁵

Affiliations

¹ Institute of Aquatic Science and Technology, College of Hydrosphere, National Kaohsiung University of Science and Technology, Kaohsiung City 81157, Taiwan.
² Institute of Aquatic Science and Technology, College of Hydrosphere, National Kaohsiung University of Science and Technology, Kaohsiung City 81157, Taiwan; Centre for Energy and Environmental Sustainability, Lucknow 226 029, Uttar Pradesh, India.
³ Diatom Research Laboratory, Amity Institute of Biotechnology, Amity University, Noida, India.
⁴ Institute of Aquatic Science and Technology, College of Hydrosphere, National Kaohsiung University of Science and Technology, Kaohsiung City 81157, Taiwan; Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City 81157, Taiwan.
⁵ Institute of Aquatic Science and Technology, College of Hydrosphere, National Kaohsiung University of Science and Technology, Kaohsiung City 81157, Taiwan; Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City 81157, Taiwan. Electronic address: cddong@nkust.edu.tw.

PMID: 37544537
DOI: 10.1016/j.biortech.2023.129635

Abstract

Microalgal astaxanthin possesses numerous bioactivities and has several health applications. The current research focuses on designing and optimizing the two-stage mixotrophic bioprocess by Chlorella zofingiensis for astaxanthin production. Gradual increase in light intensity (4-8k-lux) and 3x micronutrient concentration were the key parameters for maximizing biomass yield of 2.5 g/L during 15 days of stage I. Furthermore, stress conditions (excessive CO_2, light, salinity, etc.) enhanced astaxanthin yield at stage II. 20k lux light, 3x nutrients, and 5% CO₂ were the best ranges for maximum astaxanthin production. Maximum biomass yield and astaxanthin content were 3.3 g/L and 16.7 mg/g, respectively, after 29 days of bioprocess. Astaxanthin biosynthesis was also affected by salinity, but less than other parameters. Astaxanthin bioprocess resulted in enhanced lipid yields of 35-37%, which could be used for biodiesel. This study shows promising scale-up potential with attractive sustainability features of Chlorella zofingiensis model for commercial astaxanthin-lipid biorefinery.

Keywords: Astaxanthin; Biorefinary; Chlorella zofingiensis; Lipid; Microalgae.

MeSH terms

Biomass
Chlorella*
Lipids
Microalgae*
Xanthophylls

Substances

astaxanthine
Xanthophylls
Lipids