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Background: The decarbonization of road transport is a precondition for achieving carbon neutrality. Battery-electric vehicle technology can make this a reality. In this bias, the objective of the article is to shed light on the ongoing debate about the potentially important role of the adoption of electric vehicles in the transport of microalgae- based products to help them advance to a cleaner life cycle., Methods: Five routes, including unimodal and multimodal conditions, were defined to assess the carbon emissions of the transport system and, more specifically, of road transport. The headquarters of market-leading microalgae manufacturers were selected as the origin of the routes and, as the destination, regions that sustain them., Results: The results reveal the supremacy of road transport of microalgae-based products using electric vehicles powered by nuclear, hydroelectric, and wind, followed by biomass and photovoltaic energy. They also show that the positive impact of wind, water, and photovoltaic energy on the climate, added to the lower battery charging costs and the greater opportunity to generate revenue from the sale of carbon credits, make their tradeoffs., Conclusion: The exquisite results of this study convey key messages to decision-makers and stakeholders about the role of electromobility in building a zero-carbon delivery route., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Light energy directly affects microalgae growth and productivity. Microalgae in natural environments receive light through solar fluxes, and their duration and distribution are highly variable over time. Consequently, microalgae must adjust their photosynthetic processes to avoid photo limitation and photoinhibition and maximize yield. Considering these circumstances, adjusting light capture through artificial lighting in the main culture systems benefits microalgae growth and induces the production of commercially important compounds. In this sense, this review provides a comprehensive study of the role of light in microalgae biotechnology. For this, we present the main fundamentals and reactions of metabolism and metabolic alternatives to regulate photosynthetic conversion in microalgae cells. Light conversions based on natural and artificial systems are compared, mainly demonstrating the impact of solar radiation on natural systems and lighting devices, spectral compositions, periodic modulations, and light fluxes when using artificial lighting systems. The most commonly used photobioreactor design and performance are shown herein, in addition to a more detailed discussion of light-dependent approaches in these photobioreactors. In addition, we present the principal advances in photobioreactor projects, focusing on lighting, through a patent-based analysis to map technological trends. Lastly, sustainability and economic issues in commercializing microalgae products were presented., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Microalgae are photosynthetic microorganisms that stand out from conventional food sources and ingredients due to their high growth rate and adaptability. In addition to being highly sustainable, significant concentrations of proteins, lipids, and pigments accumulate in their cell structures from photosynthesis. Hence, this study sought to evaluate the food potential of Scenedesmus obliquus biomasses obtained from photosynthetic cultures enriched with 3, 5, 10, 15, 20, and 25% carbon dioxide (CO 2 ) (v/v). Cultivations with 3, 5, and 10% CO 2 showed greater amino acids and proteins synthesis; the protein content reached values above 56% of the dry biomass and high protein quality, due to the presence of most essential amino acids at recommended levels for the human diet. The highest concentrations of chlorophylls were found in cultures with 15, 20, and 25% CO 2 (24.2, 23.1 and 30.8 mg g -1 , respectively), although the profiles showed higher percentages of degradation compounds. Carotenoid concentrations were three times higher in cultures with 3, 5, and 10% CO 2 (25.3, 22.7 and 18.1 mg g -1 , respectively) and all-trans-β-carotene was the major compound. Lipid synthesis was intensified at higher CO 2 enrichment; the percentages obtained were 14.8% of lipids in the culture with 15% CO 2 , 15.0% with 20% CO 2 , and 13.7% with 25% CO 2 . In addition, greater polyunsaturated fatty acids accumulation and a significant reduction in the n6/n3 ratio were also observed at the highest CO 2 concentrations. Our findings showed that CO 2 treatments significantly altered all compounds concentrations in S. obliquus biomasses, which presented satisfactory composition for application in foods and as ingredients., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

In recent years, the increasing concern about human health well-being has strongly boosted the search for natural alternatives that can be used in different fields, especially in biomedicine. This has put microalgae-based products in evidence since they contain many bioactive compounds, of which polysaccharides are attractive due to the diverse physicochemical properties and new or improved biological roles they play. Polysaccharides from microalgae, specially exopolysaccharides, are critically important for market purposes because they can be used as anti-inflammatory, immunomodulatory, anti-glycemic, antitumor, antioxidant, anticoagulant, antilipidemic, antiviral, antibacterial, and antifungal agents. Therefore, to obtain higher productivity and competitiveness of these naturally available compounds, the cultivation parameters and the extraction/purification processes must be better optimized in order to bring perspectives for the exploitation of products in commercial and clinical practice. In this sense, the objective of the present review is to elucidate the potential biomedical applications of microalgae-derived polysaccharides. A closer look is taken at the main polysaccharides produced by microalgae, methods of extraction, purification and structural determination, biological activities and their applications, and current status., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

This research evaluated the carbon dioxide capture and use by Scenedesmus obliquus in a photobioreactor under different CO 2 loads. Performance indicators, carbon and energy balances, sustainability indicators, and carbon credits on the photobioreactor were assessed. The results expressed that the CO 2 loads of 384.9 kg/m 3 /d (15% CO 2 ) provide the best trade-off for the process. For this condition, maximum biomass productivities of 0.36 kg/m 3 /d, carbon dioxide conversion rates of 0.44 kgCO 2 /m 3 /d, and oxygen release rates of 0.33 kgO 2 /m 3 /d were observed, reaching maximum CO 2 removal efficiencies of 30.76%. Volatile organic compounds were the major products generated (>80%). However, only <3% was fixed in biomass. From the environmental and economic point of view, the net energy ratio was 3.44, while the potential carbon credit was of 0.04 USD per m 3 of culture. Finally, the use of adequate CO 2 loads was also proven to be determinant to improve the global performance of the system., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)