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Understanding the response of microalgae to outdoor culture conditions is necessary for the development of large open pond cultivation system for various value added applications. In this context, we evaluated the response of an indigenous oleaginous green microalga Scenedesmus obtusus CFR 1-09/FW to outdoor culture conditions. The microalga was cultivated in open ponds at various culture depths under nutrient replete condition. The pond with 3 cm culture depth showed highest biomass productivity (49.05±11.74 mg L-1 day-1). The high surface solar irradiance (1831 µmol m-2 s-1) led to a decrease in chlorophyll content (from 12.21 to 4 µg mg-1). The long duration exposure to lower temperatures (=20°C) during night led to an increase in poly unsaturated fatty acids (PUFAs) content (47.21±2.83% w/w mass fraction of FAME). The omega-3 alpha linolenic acid (ALA) content rose significantly reaching 31.01±3.79% (w/w) mass fraction of FAME. The high content of carbohydrate (23.4±0.64% w/w), protein (37.62 ± 2.15% w/w), lipid (21.55±1.43% w/w), palmitic acid (30.97±4.02% w/w mass fraction of FAME) and ALA in outdoor cultures makes this microalga a potential candidate for outdoor cultivation for food and feed applications. The study provides valuable insights for developing outdoor open pond cultivation protocol. [ABSTRACT FROM AUTHOR]

The authors reviews the advancements in carbonic anhydrase– driven processes for CO2 sequestration research and engineering. Historical and recent discoveries of carbonic anhydrase and idea behind using it for CO2 sequestration are elaborated as well as the uses of this enzyme in free and immobilized forms are thoroughly discussed. New concepts such as extension of immobilized enzyme systems for bioreactor approach with the aim of CO2 abatement at the source are also introduced briefly toward the end of the review. The authors also suggest the possible future directions to employ carbonic anhydrase for CO2 sequestration. [ABSTRACT FROM AUTHOR]

Abstract: Present investigation entails carbonic anhydrase (CA) immobilization and its influence on transformation of CO2 to calcite. CA enzyme was immobilized in alginate beads, subsequently maintained its catalytic efficiency after sequential operational cycles. The immobilized beads showed better operational stability by retaining nearly 67% of its initial activity even after six cycles. Batch scale studies with free and immobilized enzyme revealed that the entrapped CA hydrates CO2 to bicarbonate and/or carbonate which was then made to react with Ca2+ ions to transform into calcite. Calcite was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The entrapped CA was employed for the performance evaluation with respect to several operational parameters including the influence of enzyme concentration in free and immobilized condition. It was concluded that immobilized CA in alginate beads would have the potential for CO2 sequestration by biomimetic route. [Copyright &y& Elsevier]

Abstract: Waste activated sludge generated from a combined dairy and food processing industry wastewater treatment plant was evaluated for its potential to produce biodegradable plastic, poly β-hydroxybutyric acid (PHB). Deproteinized jowar grain-based distillery spentwash yielded 42.3% PHB production (w/w), followed by filtered rice grain-based distillery spentwash (40% PHB) when used as substrates. Addition of di-ammonium hydrogen phosphate (DAHP) resulted in an increase in PHB production to 67% when raw rice grain-based spentwash was used. Same wastewater, after removal of suspended solids by filtration and with DAHP supplementation resulted in lower PHB production (57.9%). However, supplementing other wastes with DAHP led to a substantial decrease in PHB content in comparison to what was observed in the absence of DAHP. [Copyright &y& Elsevier]

The study investigates the effect of catalytic ozone pretreatment via Fe 2+ and nZVI on biodegradability enhancement of complex textile effluent. The nZVI particles were synthesized and characterized by XRD, TEM and SEM analyses. Results showed that nano catalytic ozone pretreatment led to higher biodegradability index (BOD 5 /COD = BI) enhancement up to 0.61 (134.6%) along with COD, color and toxicity removal up to 73.5%, 87%, and 92% respectively. The disappearance of the corresponding GC MS & FTIR spectral peaks during catalyzed ozonation process indicated the cleavage of chromophore group and degradation of organic compounds present in the textile effluent. Subsequent aerobic biodegradation of nZVI pretreated textile effluent resulted in maximum COD and color reduction of 78% and 98.5% respectively, whereas the untreated effluent (BI = 0.26) indicated poor COD and color reduction of only 31% and 33% respectively. Bio-kinetic parameters also confirmed the increased rate of bio-oxidation at enhanced BIs. Seed germination test using seeds of Spinach ( Spinacia oleracea), indicated the effectiveness of nano catalyzed ozone pretreatment in removing toxicity from contaminated textile effluent. [ABSTRACT FROM AUTHOR]

The study investigates the effect of catalytic ozone pretreatment via Fe 2+ and nZVI on biodegradability enhancement of complex textile effluent. The nZVI particles were synthesized and characterized by XRD, TEM and SEM analyses. Results showed that nano catalytic ozone pretreatment led to higher biodegradability index (BOD 5 /COD = BI) enhancement up to 0.61 (134.6%) along with COD, color and toxicity removal up to 73.5%, 87%, and 92% respectively. The disappearance of the corresponding GCMS & FTIR spectral peaks during catalyzed ozonation process indicated the cleavage of chromophore group and degradation of organic compounds present in the textile effluent. Subsequent aerobic biodegradation of nZVI pretreated textile effluent resulted in maximum COD and color reduction of 78% and 98.5% respectively, whereas the untreated effluent (BI = 0.26) indicated poor COD and color reduction of only 31% and 33% respectively. Bio-kinetic parameters also confirmed the increased rate of bio-oxidation at enhanced BIs. Seed germination test using seeds of Spinach (Spinacia oleracea), indicated the effectiveness of nano catalyzed ozone pretreatment in removing toxicity from contaminated textile effluent., (Copyright © 2018. Published by Elsevier B.V.)