Microbial production of docosahexaenoic acid (DHA): biosynthetic pathways, physical parameter optimization, and health benefits.

Omega-3 fatty acids, including docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and α-linolenic acid (ALA), are essential polyunsaturated fatty acids with diverse health benefits. The limited conversion of dietary DHA necessitates its consumption as food supplements. Omega-3 fatty acids possess anti-arrhythmic and anti-inflammatory capabilities, contributing to cardiovascular health. Additionally, DHA consumption is linked to improved vision, brain, and memory development. Furthermore, omega-3 fatty acids offer protection against various health conditions, such as celiac disease, Alzheimer's, hypertension, thrombosis, heart diseases, depression, diabetes, and certain cancers. Fish oil from pelagic cold-water fish remains the primary source of omega-3 fatty acids, but the global population burden creates a demand-supply gap. Thus, researchers have explored alternative sources, including microbial systems, for omega-3 production. Microbial sources, particularly oleaginous actinomycetes, microalgae like Nannochloropsis and among microbial systems, Thraustochytrids stand out as they can store up to 50% of their dry weight in lipids. The microbial production of omega-3 fatty acids is a potential solution to meet the global demand, as these microorganisms can utilize various carbon sources, including organic waste. The biosynthesis of omega-3 fatty acids involves both aerobic and anaerobic pathways, with bacterial polyketide and PKS-like PUFA synthase as essential enzymatic complexes. Optimization of physicochemical parameters, such as carbon and nitrogen sources, pH, temperature, and salinity, plays a crucial role in maximizing DHA production in microbial systems. Overall, microbial sources hold significant promise in meeting the global demand for omega-3 fatty acids, offering an efficient and sustainable solution for enhancing human health.

Biobutanol production from sustainable biomass process of anaerobic ABE fermentation for industrial applications.

The growing population increases the need to develop advanced biological methods for utilizing renewable and sustainable resources to produce environmentally friendly biofuels. Currently, energy resources are limited for global demand and are constantly depleting and creating environmental problems. Some higher chain alcohols, like butanol and ethanol, processing similar properties to gasoline, can be alternate sources of biofuel. However, the industrial production of these alcohols remains challenging because they cannot be efficiently produced by microbes naturally. Therefore, butanol is the most interesting biofuel candidate with a higher octane number produced naturally by microbes through Acetone-Butanol-Ethanol fermentation. Feedstock selection as the substrate is the most crucial step in biobutanol production. Lignocellulosic biomass has been widely used to produce cellulosic biobutanol using agricultural wastes and residue. Specific necessary pretreatments, fermentation strategies, bioreactor designing and kinetics, and modeling can also enhance the efficient production of biobutanol. The recent genetic engineering approaches of gene knock in, knock out, and overexpression to manipulate pathways can increase the production of biobutanol in a user friendly host organism. So far various genetic manipulation techniques like antisense RNA, TargeTron Technology and CRISPR have been used to target Clostridium acetobutylicum for biobutanol production. This review summarizes the recent research and development for the efficient production of biobutanol in various aspects.

The impact of environment degrading factors and remittances on health expenditure: an asymmetric ARDL and dynamic simulated ARDL approach.

This paper investigates the impact of CO2 emissions, air pollution (PM2.5) exposure, foreign remittances, energy consumption, renewable energy consumption, trade openness, and gross domestic product per capita on health expenditure in a panel of the 27 highest emitting countries from 2000 to 2019. Focusing on objectives, panel ARDL, and dynamic simulated ARDL models are used to examine the short-run and long-run impact of the variables on health expenditure. An asymmetric or nonlinear ARDL model is used to test the asymmetric effect of CO2 emissions, air pollution exposure, and foreign remittance inflows on health expenditure. The results show that environment-degrading factors, remittances, and GDP per capita significantly impact health expenditure. There is an asymmetric effect of remittances, CO2 emissions, and air pollution (PM2.5) exposure on health expenditure. Based on the results, the study suggests policymakers should make policies regarding environment-degrading elements as these factors cause huge increases in health spending in a country. Consumption of renewable energy helps reduce health expenditure as it does not cause environmental degradation, irrespective of other forms of energy, and it is suggested that policies relating to foreign remittance inflows should be encouraged and made efficient.