Process design for augmentation and spectrofluorometric quantification of neutral lipid by judicious doping of pathway intermediate in the culture of marine Chlorella variabilis for biodiesel application

Consolidated bioprocessing of wastewater cocktail in an algal biorefinery for enhanced biomass, lipid and lutein production coupled with efficient CO2 capture: An advanced optimization approach

We present a holistic approach in establishing a successful green integrated bio-refinery system with improved biomass, lipid and lutein productivity, while remediating wastewater and sequestering CO₂ with potential biodiesel and healthcare applications. To achieve this we evaluated the effect of four process parameters: CO₂% supply; acetate concentration; poultry litter waste (PLW) concentration; and light intensity on cultivation of Chlorella minutissma following the Taguchi's design of experimental technique. A four factors, three levels orthogonal array was adopted to cultivate Chlorella minutissma in specially developed waste water medium. Effect of the process parameters on biomass productivity, CO₂ fixation rate, lipid content, lutein productivity and bioremediation capacity were determined. Results obtained from individual parametric combinations and Signal/Noise (S/N) ratio responses indicated S3 (5% CO₂, 100 mg L^-1 of acetate, 10 g L^-1 of poultry litter, and 15, 000 lux of light intensity) combination as the optimum cultivation condition. Following the S3 combination a significant enhancement in biomass productivity (292 mg L^-1 d^-1) with exceedingly high CO₂ fixation rate and photosynthetic efficiency (51.51 g L^-1 d^-1 of CO₂; P.E: 15.81%) was achieved. A maximum of 169.29 mg L^-1 d^-1 of lipid with a balanced distribution of saturated and unsaturated fatty acids conformed to the international standard for biodiesel was achieved. Additionally, 7.21 mg L^-1 d^-1 of lutein productivity was also accomplished within 7 day of cultivation, while remediating up to 93-90% of nitrogenous and phosphate substrates. Statistically, the results reinforced our findings with the S/N responses and experimental observations for a particular property.

Modulation of fatty acid metabolism and tricarboxylic acid cycle to enhance the lipstatin production through medium engineering in Streptomyces toxytricini

This work investigated the potential of medium engineering to obtain maximum biomass, non-conventional carbon sources for lipstatin production and modulation of tricarboxylic acid (TCA) cycle to promote lipstatin synthesis. It was found that 2:3 carbon and nitrogen ratio, produced maximum biomass of 7.9g/L in growth medium and 6.6g/L in pre-seed medium. Among the studied non-conventional carbon sources i.e., soya flour 40g/L and sesame oil 30mL/L were found producing 1109.37mg/L (1.24-fold of control) and 1196.75mg/L (1.34-fold of control) lipstatin respectively. Supplementation of TCA cycle intermediates revealed that NADH and succinic acid showed lipstatin production to 1132.99mg/L and 1171.10mg/L respectively. Experimental outcome was validated in 7L bioreactor and produced 2242.63mg/L lipstatin which was ∼14% higher than shake flask.

Integrated in situ transesterification for improved biodiesel production from oleaginous yeast: a value proposition for possible industrial implication

An integrated in situ transesterification process was developed in this study for energy and cost-efficient biodiesel production from oleaginous yeast biomass.