Cultivation of Chlorella vulgaris in sludge extract from resorcinol‐rich wastewater: the removal and inhibitory effect of sludge toxicity

Abstract

BACKGROUND The cultivation of Chlorella vulgaris present in toxic sludge extract from resorcinol‐rich wastewater was investigated to simultaneously determine the biomass production and toxicity removal. RESULTS A comparison of the blank and the toxic sludge extract revealed that the sludge toxicity originating from the degradation of resorcinol was highly correlated to the mass fraction at 5000–10000 Da (R = 0.987, P = 0.013) and led to a decline in biomass (1.49 g L−1 to 1.36 g L−1 in 30 days) along with a reduced utilization rate of organics in the sludge extract, especially in the early stage (0–5 days) of culture. The effects of sludge toxicity were characterized by the downregulation of proteins associated with carbon (C) metabolism and the upregulation of proteins involved in photoreaction by proteomics. CONCLUSION The sludge toxicity directly caused a decline in biomass production of C. vulgaris resulting from the downregulation of C metabolism. However, the promotion of biomass for heterotrophism was more significant than the inhibitory effect in the toxic sludge extract when compared with BG11 medium. © 2018 Society of Chemical Industry

Microalgae wastewater treatment: Biological and technological approaches

“…Along with photoautotrophy, several microalgal species are capable of performing chemoheterotrophic or mixotrophic metabolism, which is of interest for the treatment of industrial wastewater containing a high organic load. Among the most studied conventional microalgal strains is Chlorella vulgaris, which has been examined recently for its biomass production from food waste compost [23], sludge extracts [24], corn steep liquor, cheese whey and vinasse [25], textile waste effluent [26], tofu wastewater [27], and industrial dairy effluent [28]. Zhai et al [19] have demonstrated the high N (81.51%) and P (80.52%) removal efficiency of the widely used cyanobacterium Arthrospira platensis using a synthetic wastewater.…”