Title: Bioremediation of minkery wastewater and astaxanthin production by Haematococcus pluvialis

Authors: Yu Liu; Ilhami Yildiz

Addresses: Department of Engineering, Faculty of Agriculture, Dalhousie University, Truro-Bible Hill, NS, B2N 5E3, Canada ' Faculty of Graduate Studies, Dalhousie University, Halifax, NS B3H 4H6, Canada

Abstract: A two-stage system was designed for culturing and induction processes of H. pluvialis. H. pluvialis was cultivated in minkery wastewater and compared with the conventional Bold's basal medium, and grew better in diluted (1.5%) minkery wastewater, yielding a biomass production of 906.3 ± 34.0 mg L⁻¹. Total nitrogen and total phosphorus were also removed successfully. In the following induction stage, nitrogen-deprived vegetative cells were exposed to high light intensity for astaxanthin production, and the resultant production was 39.72 ± 1.69 mg L⁻¹. Employing the diluted wastewater, a mixotrophic induction strategy was also tested by using a series of acetate and NaCl concentrations. The findings indicated that the optimal combination for astaxanthin production was 38.14 mM acetate and 0.58% (w/v) NaCl. And the optimal astaxanthin concentration was 67.95 ± 3.93 mg L⁻¹ after a 12-day induction period. This study concludes that H. pluvialis offers a potential opportunity for treating minkery wastewater and producing high-value astaxanthin.

Keywords: bioremediation; minkery wastewater; water pollution; wastewater treatment; Haematococcus pluvialis; algal biomass; astaxanthin; photoautotrophy; mixotrophy; nutrient deprivation; nutrient stress; light stress; surface response methodology; Nova Scotia.

DOI: 10.1504/IJGW.2019.101778

International Journal of Global Warming, 2019 Vol.19 No.1/2, pp.145 - 157

Received: 06 Nov 2018
Accepted: 19 Apr 2019
Published online: 26 Aug 2019 *

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