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The rise of the global mean temperature as a consequence of incessant anthropogenic greenhouse gas (GHG) emissions, led by CO2, is one of the direst challenges faced by humankind today. The need of the hour is to minimize fossil fuel usage and capture the atmospheric CO2. Broadly, the CO2 mitigation strategies employ carbon capture and storage (CCS) and biological carbon capture and utilization (bio-CCU) technologies. A critical comparative summary of the prevalent CCS and bio-CCU methods has been presented in this study. Among all the CO2 capture technologies, the microalgal bio-CCU in a biorefinery model is more environment and economy-friendly. Microalgal biorefinery can potentially serve as a platform not only for bio-CCU but also for producing third-generation biofuels and commercially important value-added products as means of wealth generation from waste CO2. Alongside reducing the world's reliance on fossil fuels, this approach also directly or indirectly addresses most of the UN's sustainable development goals (SDGs). To enhance the microalgal CO2 capture efficiency and consequent biomass productivity, smart bioprocess design and reactor engineering performed by researchers are summarized to understand the progress in this direction. Recent advances, innovations, and existing challenges in the design and development of microalgal cultivation processes and systems, including CO2 delivery mechanisms, have been critically discussed and assessed in terms of carbon capture efficiency. The futuristic vision for the fourth-generation microalgal biorefinery-based bio-CCU has also been outlined to make some practical recommendations for its successful implementation or adaptation by the thermal power plants and cement industries. [ABSTRACT FROM AUTHOR]

BACKGROUND: Natural photosynthesis, utilizing intelligent molecular machinery to harness sunlight, stands as the benchmark for efficient energy generation. Despite its high quantum efficiency compared to synthetic methods, challenges persist due to dynamic nutritional and light requirements in plant, microalgae, and cyanobacteria‐driven processes. Reported microalgae CO2 uptake rates rely on biomass dry cell weight measurement after certain incubation period and systematic study of required CO2 concentrations for optimal photobioreactor operation remaining unexplored. This research is thus aimed at evaluating the critical dissolved CO2 (Ccrit ∙ CO2) concentration and specific CO2 uptake rates (SCUR) of Chlorella minutissima (CM) culture in the presence of surplus light and other nutrients by online monitoring and measuring the dynamic CO2 uptake rates which will help in maintaining the optimal rate of CO2 delivery for continuous cultivation of microalgae while minimizing the escape of CO2. RESULTS: Dissolved Ccrit ∙ CO2 was determined to be in the range of 16–20 mg/L, and the maximum SCUR in BBM (Bold Basal Medium) was found to be 0.73 mg CO2 (mg dcw ∙ h)−1. Interestingly, this SCUR value is nearly three times greater than that of the most efficient in vitro artificial photosynthetic novel pathway reported so far. CONCLUSION: From the calculated SCUR values, it may be noted that 9.6 g of biomass can be obtained from 1 g of microalgal inoculum in a day, thereby setting a benchmark for the scientists working in the areas of bioprocess engineering, synthetic biology, and metabolic engineering to comply. © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

This study aimed to compare the untreated, cold plasma (CP)‐optimized (30 kV/5 mm/6.7 min), CP‐extreme (30 kV/2 mm/10 min), and thermally treated (TT) (90 ℃/5 min) kiwifruit juices based on the physicochemical (pH, total soluble solids (TSS), titratable acidity (TA), total color change (ΔE)), physical (particle size and rheology), microstructure (optical microscope), bioactive compounds (polyphenol, ascorbic acid, and sugar compounds), and sensory characteristics of kiwifruit juice. The pH, TSS, and TA were not significantly affected in CP and TT juice, whereas the ΔE (6.52) of TT juice lies in the range of "greatly visible." The microstructure characteristics of juice significantly changed after CP and thermal treatment. The cell and tissue disruption in CP‐extreme and thermally treated juice was more than CP‐optimized. The particle size of juice decreased irrespective of treatment, but the span value of CP‐optimized juice was the lowest. Further, the CP treatment showed a lower consistency index, apparent viscosity, and pseudoplasticity of juice than the thermal treatment. The CP‐treated juice retained bioactive and nutritional attributes more than thermally treated juice. The CP‐optimized, CP‐extreme, and thermal treatment reduced the sucrose content by 54, 55, and 23%, while the fructose and glucose content were increased by 17, 12, & 93%, and 17, 11 & 99%, respectively. Among the CP‐treated juice, CP‐optimized (71.36 mg/100g) contained a higher amount of ascorbic acid than the CP‐extreme (64.36 mg/100g). Based on the similarity values in the fuzzy logic analysis, the sensory attributes of CP‐optimized treated juice were superior to CP‐extreme and thermal treated. Practical Application: In this era, non‐thermal processing techniques are trending for retaining the nutrition and stability of juice. The old plasma (CP)‐treated kiwifruit juice had better nutritional, bioactive compounds, and sensory attributes than the thermally treated juice. Further, the CP‐treated juice had higher flowability and lower viscosity, making it ideal for juice processing. The conclusions drawn suggest that CP processing is a better alternative for processing kiwifruit juice than thermal processing. [ABSTRACT FROM AUTHOR]