Methods of determing biokinetics of arsenate accumulation and release in Microcystis aeruginosa regulated by common environmental factors: Practical implications for enhanced bioremediation

Only little information is available on combined effects of abiotic environmental factors on algal arsenate (As-v) metabolic biokinetics. Herein, we demonstrated the methods of using the Taguchi statistical method to investigate four environmental factors including As-v, nitrate (N), orthophosphate (P) and pH for their combined effects on algal growth and arsenic (As) uptake but also extracellular adsorption of Micro cystis aeruginosa, as well as As release from dead algal cells. Results showed that an increase of N facilitated M. aeruginosa growth and thus was the principal factor for the algal maximum specific growth rate (mu(max)). P was vital to As-v bioconcentration factor (BCF) and As partition coefficients (LogK(d)) released from deal algal cells. As-v impacted the extracellular As adsorption onto the algal cells, which thereby increased with increasing initial As-v level. The initial pH had an imperative effect on the As-v uptake (k(u)) and release rate (K-e) from the dead cells. Collectively, the condition of low P, high N and alkaline pH level was favorable toAs accumulation rate of living cells and restrictive to As release rate from dead cells of M. aeruginosa. The obtained information can pave a road for extensive understanding on efficient utilization of As bioremediation of algae in practical environment. Principal factors were identified on As-v metabolic biokinetics by Taguchi method. High N and pH but low P fasten As-v uptake and reduce As efflux from dead cells. As-v only as the main factor impacted As extracellular adsorption on algal cells. (C) 2018 The Author(s). Published by Elsevier B.V.