Performance evaluation of biocatalytic and biostimulation approaches for the remediation of trace organic contaminants in municipal biosolids

Laccase-Driven Transformation of High Priority Pesticides Without Redox Mediators: Towards Bioremediation of Contaminated Wastewaters

“…To prevent evaporation, the flasks were kept in complete darkness in a static incubator at 30 °C, and 90% humidity. In addition to routine analysis, including dry matter, moisture content, and pH, sampling was taken every 24 h of fermentation by removing 2 g of the content of each flask to continuously monitor total protein (Rathankumar et al, 2020), total reducing sugar (Rathankumar et al, 2020), chemical oxygen demand (Vaithyanathan et al, 2021a), total suspended solids (Vaithyanathan et al, 2021b), volatile suspended solids, total dissolved solids (Vaithyanathan et al, 2021b), ligninolytic enzymes like laccase (Touahar et al, 2014), lignin peroxidase (Lip; Ariste et al, 2020), aryl alcohol oxidase (AAO; Ariste et al, 2020), and cellulase (Vaithyanathan et al, 2021a). Enzyme activities were measured spectrophotometrically using a double beam SpectraMax Plus 384 UV-Vis spectrophotometer (Molecular Devices Corporation, Sunnyvale, CA, USA).…”

Integrated Biotechnology Management of Biosolids: Sustainable Ways to Produce Value—Added Products

“…In aerobic or anaerobic digestion, nutrient-rich BS are converted into energy or bioproducts and stable organic residue is obtained (Wainaina et al, 2020). However, in the biological process, hydrolysis is the rate-limiting step because extracellular enzymes produced by indigenous microorganisms are immobilized inside the floc, which makes them unavailable for the hydrolysis of readily available and large organic matter, which in turn affect the stabilization of BS (Vaithyanathan et al, 2021b).…”

“…The VAPs obtained from the sludge valorization using aerobic bioaugmentation are listed in Table 3. The promising VAPs are biodiesel from Trichosporon oleaginosus (Zhang et al, 2014;Chen et al, 2021), enzymes from Aspergillus niger (Vaithyanathan et al, 2020), T. versicolor (Rodríguez-Rodríguez et al, 2011Llorens-Blanch et al, 2018) and Bacillus subtilis (Vaithyanathan et al, 2021b), biopesticide from B. thuringiensis, (Balasubramanian and Tyagi, 2017a;Cerda et al, 2019) and biosurfactant from Starmerella bombicola (Cerda et al, 2019). These products have future applications in extraction and production, and thus, provide a way for waste disposal and cost-effective production of VAPs.…”

“…At the current global population growth rate, the generation of solid wastes like BS is bound to increase dramatically. Canada produces 660,000 dry tons of biosolids annually (CCME, 2012;Jin et al, 2018;Vaithyanathan et al, 2021b). These BS are either disposed of or used in land applications (CCMEA, 2010;Gherghel et al, 2019).…”

“…BS containing pathogens and hazardous contaminants affect the soil vegetation and ground water level, so proper treatment and disposal of BS are necessary to protect the environment; this disposal could represent up to 50% of the total operating cost of WWTPs (Rathankumar et al, 2020;Vaithyanathan et al, 2021b). Moreover, BS disposal could be responsible for up to 40% of greenhouse gases (GHG) emissions from WWTPs (Qian et al, 2016;Gherghel et al, 2019).…”