Microbial communities in hybrid linear flow channel reactors and anaerobic sequencing batch reactors operated in series for remediation and beneficiation of tannery wastewater were assessed. Despite concurrent sulfidogenesis, more intensive pre-treatment in hybrid linear flow channel reactors reduced methanogenic inhibition usually associated with anaerobic digestion of tannery effluent and promoted efficiency (max 321 mLCH₄/gCOD_consumed, 59% biogas CH₄). Nitrification and biological sulfate reduction were key metabolic pathways involved in overall and sulfate reducing bacterial community selection, respectively, during pre-treatment. Taxonomic selection could be explained by the proteinaceous and saline character of tannery effluent, with dominant genera being protein and/or amino acid degrading, halotolerant and/or ammonia tolerant. Complete oxidizers dominated the sulfidogenic populations during pre-treatment, while aceticlastic genera dominated the methanogenic populations during anaerobic digestion. With more intensive pre-treatment, the system shows promise for remediation and recovery of biogas and sulfur from tannery wastewater in support of a bio-circular economy.

The anti‐cancer potential of Cyclopia species (honeybush) has been demonstrated in several models. The present study investigated the effects of aqueous and polyphenol‐enriched (PE) extracts of C. subternata and C. genistoides , as well as mangiferin and hesperidin, on different cell growth parameters in human liver (HepG2) and colon (HT‐29) cancer cells. Mangiferin and hesperidin were most abundant in C. genistoides and C. subternata , respectively. Cyclopia subternata extracts had the highest ferric‐reducing antioxidant capacity. Following exposure of the cells to the extracts and compounds, cell viability, proliferation, and death (apoptosis and autophagy) were determined. Cyclopia subternata extracts reduced cell viability and inhibited cell proliferation the most, associated with depletion of ATP. In HepG2 cells, the PE extracts were less effective than the aqueous extracts in reducing cell viability but more effective in inhibiting cell proliferation. Despite disrupting cell growth, none of the extracts induced apoptosis. The aqueous extracts affected autophagy in both cancer cells. Disruption of mitochondrial membrane integrity by the different extracts, presumably via polyphenol/iron interactions, is postulated to be involved; however, mangiferin and hesperidin had no effect, suggesting that other polyphenols and/or complex interactions between compounds are likely responsible for the differential cytotoxic and/or cytoprotective effects of the extracts.

In maize subsistence farming areas in South Africa, daily consumption of maize contaminated by high level of mycotoxins contributes to long-term health effects such as immune deficiency and cancer. Biocontrol methods that are safe and cost-effective are critical to addressing this public health problem.