UV-C mediated rapid carotenoid induction and settling performance of Dunaliella salina and Haematococcus pluvialis (Biotechnology and Bioengineering)

Microalgae are primary producers of organic pigments carotenoids in aquatic environments. However, commercial-scale microalgae application for high value carotenoids production is rarely economical due to the cost-effectiveness of carotenoid induction and microalgal harvesting process. Here, we present a novel approach, using a small dose of externally applied UV-C radiation, to rapidly induce unsaturated fatty acids and carotenoid biosynthesis in Dunaliella salina and Haematococcus pluvialis, and also to significantly promote their swimming cells settling for primary dewatering. The amount of total carotenoids and ?-carotenoid were doubled in 24 h on D. salina upon 50 mJ/cm2 of UV-C radiation, whereas the astaxanthin yield of H. pluvialis was increased 5 times in 48 h at 30 mJ/cm2. Meanwhile, 95% of algal cells of D. salina and H. pluvialis settled in 15 h and 2 h, respectively. This novel technique represents a convenient, time-saving and cost-effective method for commercial microalgal carotenoids production. This article is protected by copyright. All rights reserved