Adaptive laboratory evolution empowers lipids and biomass overproduction in Chlorella vulgaris for environmental applications.

Microalgal strain improvement with commercial features is needed to generate green biological feedstock to produce lipids for bioenergy. Hence, improving algal strain with enhanced lipid content without hindering cellular physiological parameters is pivotal for commercial applications of microalgae. In this report, we demonstrated the adaptive laboratory evolution (ALE) by hypersaline conditions to improve the algal strains for increasing the lipid overproduction capacity of Chlorella vulgaris for environmental applications.

Photosynthetic response mechanism to polybrominated diphenyl ether exposure in Chlorella pyrenoidosa.

Polybrominated diphenyl ether (PBDE) contamination is common in aquatic environments and can severely damage aquatic organisms. However, there is a lack of information on the response and self-adaptation mechanisms of these organisms. Chlorella pyrenoidosa was treated with 2,2',4,4'-tetrabromodiphenyl ether (BDE47), causing significant growth inhibition, pigment reduction, oxidative stress, and chloroplast atrophy.

Bioremediation of Catechol and Concurrent Accumulation of Biocompounds by the Microalga .

Burgeoning commercial applications of catechol have led to its excessive accumulation in the environment, thereby posing a severe ecological threat. Bioremediation has emerged as a promising solution. The potential of the microalga to degrade catechol and use the byproduct as a carbon source was investigated in this study.

Distortion Prediction in Inconel-718 Part Fabricated through LPBF by Using Homogenized Support Properties from Experiments and Numerical Simulation.

The Laser Powder-Bed Fusion (LPBF) process produces complex part geometry by selectively sintering powder metal layer upon layer. During the LPBF process, parts experience the challenge of residual stress, distortions, and print failures. Lattice-based structures are used to support overhang parts and reduce distortion; this lattice support has complex geometry and demands high computational effort to predict distortion using simulation.

Supplementation with -GR24 Facilitates the Accumulation of Biomass and Astaxanthin in Two Successive Stages of Cultivation.

The unicellular freshwater green alga has attracted much research attention due to its biosynthetic ability for large amounts of astaxanthin, a blood-red ketocarotenoid that is used in cosmetics, nutraceuticals, and pharmaceuticals. Recently, numerous studies have investigated the functions of natural astaxanthin; however, the high cost of the production of astaxanthin from cultures restricts its commercial viability. There is an urgent need to fulfill commercial demands by increasing astaxanthin accumulation from cultures.

Effective bioremediation of tobacco wastewater by microalgae at acidic pH for synergistic biomass and lipid accumulation.

Tobacco wastewater is too difficult to decontaminate which poses a significant environmental problem due to the harmful and toxic components. Chlorella pyrenoidosa is a typical microalgal species with potential in removal of organic/inorganic pollutants and proves to be an ideal algal-based system for wastewater treatment. However, the strategy of tobacco related wastewater treatment using microalgae is in urgent need of development.

Hyperaccumulation of fucoxanthin by enhancing methylerythritol phosphate pathway in Phaeodactylum tricornutum.

The established human health benefits of carotenoids along with the contemporary consumption of natural carotenoids bring the necessity to sustainable production of carotenoids. Among, marine diatoms have emerged as the potential biological resources for carotenoid production; however, their relatively lower yield in native strains provides the impetus to genetically improve the diatoms to cope with the burgeoning demand. In this study, we genetically improved the diatom Phaeodactylum tricornutum by overexpressing key carotenogenic genes involved in methylerythritol phosphate (MEP) pathway.

Hydrolysis of organophosphorus by diatom purple acid phosphatase and sequential regulation of cell metabolism.

Phosphorus (P) limitation affects phytoplankton growth and population size in aquatic systems, and consequently limits aquatic primary productivity. Plants have evolved a range of metabolic responses to cope with P limitation, such as accumulation of purple acid phosphatases (PAPs) to enhance acquisition of phosphates. However, it remains unknown whether algae have evolved a similar mechanism.

Metabolic Engineering of Isoflavonoid Biosynthesis by Expressing in L. for Genistein Production.

Isoflavonoids, the diverse group of secondary metabolites derived from the phenylpropanoid pathway, are distributed predominantly in leguminous plants and play a vital role in promoting human health. Genetic engineering of the metabolite synthesis pathway has turned out to be an attractive approach for the production of various secondary metabolites. In our study, we attempted to produce the isoflavone genistein, a well-known health-promoting metabolite, in L.

Molybdenum disulfide nanoparticles concurrently stimulated biomass and β-carotene accumulation in Dunaliella salina.

Molybdenum disulfide nanoparticles (MoS NPs) hold tremendous properties in wide domain of applications. In this study, the impact of MoS NPs was investigated on algal physiological and metabolic properties and a two-stage strategy was acquired to enhance the commercial potential of Dunaliella salina. With 50 µg/L of MoS NPs exposure, cellular growth and biomass production were promoted by 1.

Physiological and molecular responses in halotolerant Dunaliella salina exposed to molybdenum disulfide nanoparticles.

Molybdenum disulfide nanoparticles (MoS NPs) has emerged as the promising nanomaterial with a wide array of applications in the biomedical, industrial and environmental field. However, the potential effect of MoS NPs on marine organisms has yet to be reported. In this study, the effect of MoS NPs on the physiological index, subcellular morphology, transcriptomic profiles of the marine microalgae Dunaliella salina was investigated for the first time.

TAG pathway engineering via GPAT2 concurrently potentiates abiotic stress tolerance and oleaginicity in .

Background: Despite the great potential of marine diatoms in biofuel sector, commercially viable biofuel production from native diatom strain is impractical. Targeted engineering of TAG pathway represents a promising approach; however, recruitment of potential candidate has been regarded as critical. Here, we identified a glycerol-3-phosphate acyltransferase 2 (GPAT2) isoform and overexpressed in .

Sustainable and stepwise waste-based utilisation strategy for the production of biomass and biofuels by engineered microalgae.

Waste streams have emerged as potential feedstocks for biofuel production via microbial bioconversion. Metabolic engineering of the microalga Phaeodactylum tricornutum in its lipid biosynthetic pathways has been conducted with an aim to improve lipid production. However, there has been only limited achievement in satisfying biofuel demands by utilising extracellular organic carbons from low-cost waste streams.

Enhanced polyunsaturated fatty acid production using food wastes and biofuels byproducts by an evolved strain of Phaeodactylum tricornutum.

This study investigates the prospective of utilizing kitchen wastewater and food wastes, biofuels industry byproducts as alternative water and carbon sources. Kitchen wastewater did not impede cellular growth rate of the evolved Phaeodactylum strain E70, which indicates its potential as an alternative to freshwater resources. Among the organic wastes assessed, food waste hydrolysate significantly increased cell growth.

Rapid and Effective Electroporation Protocol for Nannochloropsis oceanica.

Electroporation refers to the application of high strength electric pulse to create transient pores in the membrane, thereby enabling the passage of hydrophilic molecules into the cells. Based on the properties of cell and cell wall, the electroporation parameters vary among the algal species. Here, we demonstrated the optimized protocol for successful introduction of recombinant DNA (~5000 bp) into Nannochloropsis oceanica.

Glucose-6-Phosphate Dehydrogenase from the Oleaginous Microalga Nannochloropsis Uncovers Its Potential Role in Promoting Lipogenesis.

Microalgae have long been considered as potential biological feedstock for the production of wide array of bioproducts, such as biofuel feedstock because of their lipid accumulating capability. However, lipid productivity of microalgae is still far below commercial viability. Here, a glucose-6-phosphate dehydrogenase from the oleaginous microalga Nannochloropsis oceanica is identified and heterologously expressed in the green microalga Chlorella pyrenoidosa to characterize its function in the pentose phosphate pathway.

Potentiation of concurrent expression of lipogenic genes by novel strong promoters in the oleaginous microalga Phaeodactylum tricornutum.

There has been growing interest in using microalgae as production hosts for a wide range of value-added compounds. However, microalgal genetic improvement is impeded by lack of genetic tools to concurrently control multiple genes. Here, we identified two novel strong promoters, designated Pt202 and Pt667, and delineated their potential role on simultaneously driving the expression of key lipogenic genes in Phaeodactylum tricornutum.

Ethanol induced jasmonate pathway promotes astaxanthin hyperaccumulation in Haematococcus pluvialis.

Haematococcus pluvialis is a main biological resource for the antioxidant astaxanthin production, however, potential modulators and molecular mechanisms underpinning astaxanthin accumulation remain largely obscured. We discovered that provision of ethanol (0.4%) significantly triggered the cellular astaxanthin content up to 3.

Transcriptional regulation of microalgae for concurrent lipid overproduction and secretion.

Commercialization of algal lipids and biofuels is still impractical owing to the unavailability of lipogenic strains and lack of economically viable oil extraction strategies. Because lipogenesis is governed by multiple factors, success in generating industrial-suitable algal strains using conventional strategies has been limited. We report the discovery of a novel bZIP1 transcription factor, NobZIP1, whose overexpression results in a remarkable elevation of lipid accumulation and lipid secretion in a model microalga , without impairing other physiological properties.

Dual expression of plastidial GPAT1 and LPAT1 regulates triacylglycerol production and the fatty acid profile in .

Background: Metabolic engineering has emerged as a potential strategy for improving microalgal lipid content through targeted changes to lipid metabolic networks. However, the intricate nature of lipogenesis has impeded metabolic engineering. Therefore, it is very important to identify the crucial metabolic nodes and develop strategies to exploit multiple genes for transgenesis.

The role of diatom glucose-6-phosphate dehydrogenase on lipogenic NADPH supply in green microalgae through plastidial oxidative pentose phosphate pathway.

Commercial production of biofuel from oleaginous microalgae is often impeded by their slow growth rate than other fast-growing algal species. A promising strategy is to genetically engineer the fast-growing algae to accumulate lipids by expressing key lipogenic genes from oleaginous microalgae. However, lacking of strong expression cassette to transform most of the algal species and potential metabolic target to engineer lipid metabolism has hindered its biotechnological applications.

Quercetin potentiates the concurrent hyper-accumulation of cellular biomass and lipids in Chlorella vulgaris.

Provision of chemical modulators has emerged as an effective strategy to govern cell growth and development. Here, the impact of flavonoid quercetin on algal growth, lipid accumulation and transcriptional patterns was investigated in the green microalga Chlorella vulgaris. These results demonstrated that quercetin (15 μg/l) significantly enhanced the cellular biomass and photosynthetic efficiency, with up to 2.

Overproduction of Bioactive Algal Chrysolaminarin by the Critical Carbon Flux Regulator Phosphoglucomutase.

Chrysolaminarin, the primary polysaccharide reservoir in some marine algae, has attracted much attention due to its broad health properties. However, its biosynthetic pathway and regulation mechanisms have rarely been reported which hinders the improvement of production efficiency. Therefore, this study aims to identify key metabolic nodes in the chrysolaminarin biosynthetic pathway.

Constitutive and Chloroplast Targeted Expression of Acetyl-CoA Carboxylase in Oleaginous Microalgae Elevates Fatty Acid Biosynthesis.

Photosynthetic microalgae are of burgeoning interest in the generation of commercial bioproducts. Microalgae accumulate high lipid content under adverse conditions, which in turn compromise their growth and hinder their commercial potential. Hence, it is necessary to engineer microalgae to mitigate elevated lipid accumulation and biomass.

High-efficiency promoter-driven coordinated regulation of multiple metabolic nodes elevates lipid accumulation in the model microalga Phaeodactylum tricornutum.

Background: Microalgal metabolic engineering holds great promise for the overproduction of a wide range of commercial bioproducts. It demands simultaneous manipulation of multiple metabolic nodes. However, high-efficiency promoters have been lacking.