Challenges and prospects for sustainable microalga-based oil: A comprehensive review, with a focus on metabolic and genetic engineering

• Type: Article in International Scientific Journal
• Date: 2022

Authors

F. Xavier Malcata (Author) FEUP; Ranjbar, S. (Author) Other

Journal

Title: Fuel

ISSN: 0016-2361

Publisher: Elsevier

Indexing

ISI Web of Knowledge

ISI Web of Science

Scientific classification

CORDIS: Technological sciences

FOS: Engineering and technology

Associated Projects

LEPABE - Financiamento Plurianual 2020-2023 da Unidade de I&D LEPABE - Laboratório de Engenharia de Processos, Ambiente, Biotecnologia e Energia

ALiCE - ALiCE - Laboratório Associado em Engenharia Química

Other information

DOI: 10.1016/j.fuel.2022.124567

Abstract (EN): Excessive combustion of fossil fuels for energy production, with concomitant release to the atmosphere of huge amounts of gases bearing greenhouse effects have urged search for renewable sources of energy; manufacture of biodiesel from oils entails one such possibility, provided that no land area necessary for food gets occupied. Microalgae accordingly arise as the best option – since they use essentially sunlight as source of metabolic energy, and synthesize and accumulate a substantial fraction of oil by resorting to atmospheric CO2 as carbon source; hence, they simultaneously contribute to sequester this gas. Unfortunately, the volumetric productivities of oil by microalgae are still poor, and it is typically accumulated in their cytoplasm; this calls for genetic engineering, aimed at enhancing synthesis of oils and facilitating excretion thereof. Recent advances in development of molecular tools have opened new perspectives toward tailor-made cell factories – encompassing systems and synthetic biology, bioinformatics and other omics technologies. However, a holistic approach to metabolic engineering must take several aspects of cellular metabolism into account – namely, transcription factors, transporters, competing pathways, and balance between growth and proliferation. This review covers recent advances in the field under scrutiny, as well as chief technical issues to be addressed when attempting to harness the enormous potential of microalgae; complemented by a realistic assessment of risks and opportunities of resorting to genetically-transformed microalgae. An overview of challenges and prospects concerning technical applicability and economic feasibility is also put forward – including a discussion of ethical concerns associated with the large-scale use of genetically engineered strains.

Type (Professor's evaluation): Scientific