Concerns about environmental safety have led to strict regulations on the discharge of final brewery effluents into water bodies. Brewery wastewater contains huge amounts of organic compounds that can cause environmental pollution. The microalgae wastewater treatment method is an emerging environmentally friendly biotechnological process. Microalgae grow well in nutrient-rich wastewater by absorbing organic nutrients and converting them into useful biomass. The harvested biomass can be used as animal feed, biofertilizer, and an alternative energy source for biodiesel production. This review discusses conventional and current brewery wastewater treatment methods, and the application and potential of microalgae in brewery wastewater treatment. The study also discusses the benefits as well as challenges associated with microalgae brewery and other industrial wastewater treatments.
The alcohol industry discharges large quantities of wastewater, which is hazardous and has a considerable pollution potential. Cultivating microalgae in wastewater is an alternative way of overcoming the current high cost of microalgae cultivation and an environmentally friendly treatment method for industrial effluents. The study analyzed the growth and biochemical composition of Chlorella vulgaris cultivated in membrane-treated distillery wastewater (MTDW) and nutrients removal efficiency. The results showed biomass productivity of 0.04 g L−1 d−1 for MTDW with the contents of content of protein, carbohydrate, and lipid at 49.6 ± 1.4%, 26.1 ± 0.6%, and 10.4 ± 1.8%, respectively. The removal efficiencies of TN, TP, and COD were 80, 94, and 72.24% in MTDW, respectively. In addition, removal efficiencies of 100, 85.37, and 42.86% for Ca2+, Mg2+, and Mo2− were achieved, respectively. The study added to our growing knowledge on the cultivation of Chlorella with wastewater, suggesting that it was feasible to cultivate Chlorella with MTDW and represented an economical and environmentally friendly strategy for microalgae biomass production and reuse of wastewater resources.
Silver sillago (Sillago sihama) is a commercially important marine fish species in East Asia. In this study, we compared the transcriptome response to hypoxia stress in the gill tissue of S. sihama. The fish were divided into four groups, such as 1 h of hypoxia (hypoxia1h, DO = 1.5 ± 0.1 mg/L), 4 h of hypoxia (hypoxia4h, DO = 1.5 ± 0.1 mg/L), 4 h of reoxygen (reoxygen4h, DO = 8.0 ± 0.2 mg/L) after 4 h of hypoxia (DO = 1.5 mg/L), and normoxia or control (DO = 8.0 ± 0.2 mg/L) groups. Compared to the normoxia group, a total of 3550 genes were identified as differentially expressed genes (DEGs) (log2foldchange > 1 and padj < 0.05), including 1103, 1451 and 996 genes in hypoxia1h, hypoxia4h and reoxygen4h groups, respectively. Only 247 DEGs were differentially co-expressed in all treatment groups. According to Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, DEGs were significantly enriched in steroid biosynthesis, biosynthesis of amino acids, glutathione metabolism and metabolism of xenobiotics by cytochrome P450, ferroptosis and drug metabolism—cytochrome P450 pathways. Of these, the cytochrome P450 (CYP) and glutathione S-transferase (GST) gene families were widely expressed. Our study represents the insights into the underlying molecular mechanisms of hypoxia stress.