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Journal of Agricultural and Food... Dec 2023The presence of multiple conjugated double bonds and chiral carbon atoms endows astaxanthin with geometric and optical isomers, and these isomers widely exist in... (Review)
Review
The presence of multiple conjugated double bonds and chiral carbon atoms endows astaxanthin with geometric and optical isomers, and these isomers widely exist in biological sources, food processing, and absorption. However, there remains no systematic summary of astaxanthin isomers regarding isomerization methods and analytic techniques. To address this need, this Review focuses on a comprehensive analysis of -isomerization methods of astaxanthin, including solvent system, catalyst, and heat treatment. Comparatively, high-efficiency and health-friendly methods are more conducive to put into practical use, such as food-grade solvents and food-component catalysts. In addition, we outline the recent advances in analysis techniques of astaxanthin isomers, as well as the structural characteristics reflected by various methods (e.g., HPLC, NMR, FTIR, and RS). Furthermore, we summarized the related research on the safety evaluation of astaxanthin isomers. Finally, future trends and barriers in transformation and analysis of astaxanthin isomers are also discussed.
Topics: Isomerism; Xanthophylls; Chemical Phenomena; Catalysis; Solvents
PubMed: 37924299
DOI: 10.1021/acs.jafc.3c06863 -
Critical Reviews in Food Science and... 2023Astaxanthin is a carotenoid widely found in marine organisms and microorganisms. With extensive use in nutraceuticals, cosmetics, and animal feed, astaxanthin will have... (Review)
Review
Astaxanthin is a carotenoid widely found in marine organisms and microorganisms. With extensive use in nutraceuticals, cosmetics, and animal feed, astaxanthin will have the largest share in the global market for carotenoids in the near future. Owing to its unique molecular features, astaxanthin has excellent antioxidant activity and holds promise for use in biochemical studies. This review focuses on the observed health benefits of dietary astaxanthin, as well as its underlying bioactivity mechanisms. Recent studies have increased our understanding of the role of isomerization and esterification in the structure-function relationship of dietary astaxanthin. Gut microbiota may involve the fate of astaxanthin during digestion and absorption; thus, further knowledge is needed to establish accurate recommendations for dietary intake of both healthy and special populations. Associated with the regulation of redox balance and multiple biological mechanisms, astaxanthin is proposed to affect oxidative stress, inflammation, cell death, and lipid metabolism in humans, thus exerting benefits for skin condition, eye health, cardiovascular system, neurological function, exercise performance, and immune response. Additionally, preclinical trials predict its potential effects such as intestinal flora regulation and anti-diabetic activity. Therefore, astaxanthin is worthy of further investigation for boosting human health, and wide applications in the food industry.
Topics: Animals; Humans; Carotenoids; Xanthophylls; Antioxidants; Dietary Supplements
PubMed: 34581210
DOI: 10.1080/10408398.2021.1983766 -
Bioresource Technology Jan 2022The green microalga Haematococcus pluvialis is an excellent source of astaxanthin, a powerful antioxidant widely used in cosmetics, aquaculture, health foods, and... (Review)
Review
The green microalga Haematococcus pluvialis is an excellent source of astaxanthin, a powerful antioxidant widely used in cosmetics, aquaculture, health foods, and pharmaceuticals. This review explores recent developments in cell disruption and astaxanthin extraction techniques applied using H. pluvialis as a model species for large-scale algal biorefinery. Notably, this alga develops a unique cyst-like cell with a rigid three-layered cell wall during astaxanthin accumulation (∼4% of dry weight) under stress. The thick (∼2 µm), acetolysis-resistant cell wall forms the strongest barrier to astaxanthin extraction. Various physical, chemical, and biological cell disruption methods were discussed and compared based on theoretical mechanisms, biomass status (wet, dry, and live), cell-disruption efficacy, astaxanthin extractability, cost, scalability, synergistic combinations, and impact on the stress-sensitive astaxanthin content. The challenges and future prospects of the downstream processes for the sustainable and economic development of advanced H. pluvialis biorefineries are also outlined.
Topics: Antioxidants; Biomass; Chlorophyceae; Xanthophylls
PubMed: 34653624
DOI: 10.1016/j.biortech.2021.126124 -
Applied Microbiology and Biotechnology Jul 2020Astaxanthin is a natural pigment, known for its strong antioxidant activity and numerous health benefits to human and animals. Its antioxidant activity is known to be... (Review)
Review
Astaxanthin is a natural pigment, known for its strong antioxidant activity and numerous health benefits to human and animals. Its antioxidant activity is known to be substantially greater than β-carotene and about a thousand times more effective than vitamin E. The potential health benefits have generated a growing commercial interest, and the escalating demand has prompted the exploration of alternative supply chain. Astaxanthin naturally occurs in many sea creatures such as trout, shrimp, and microalgae, some fungi, bacteria, and flowering plants, acting to protect hosts against environmental stress and adverse conditions. Due to the rapid growth and simple growth medium requirement, microbes, such as the microalga, Haematococcus pluvialis, and the fungus Xanthophyllomyces dendrorhous, have been developed to produce astaxanthin. With advances in metabolic engineering, non-carotenogenic microbes, such as Escherichia coli and Saccharomyces cerevisiae, have been purposed to produce astaxanthin and significant progress has been achieved. Here, we review the recent achievements in microbial astaxanthin biosynthesis (with reference to metabolic engineering strategies) and extraction methods, current challenges (technical and regulatory), and commercialization outlook. Due to greenness, sustainability, and dramatic cost reduction, we envision microbial synthesis of astaxanthin offers an alternative means of production (e.g. chemical synthesis) in the near future.
Topics: Bacteria; Bioreactors; Biosynthetic Pathways; Fungi; Metabolic Engineering; Microalgae; Xanthophylls; beta Carotene
PubMed: 32399589
DOI: 10.1007/s00253-020-10648-2 -
Nutrients Apr 2022Astaxanthin (ASX) is a natural product and one of the most powerful antioxidants known. It has significant effects on the metabolism of many animals, increasing... (Review)
Review
Astaxanthin (ASX) is a natural product and one of the most powerful antioxidants known. It has significant effects on the metabolism of many animals, increasing fecundity, egg yolk volume, growth rates, immune responses, and disease resistance. A large part of the bioactivity of ASX is due to its targeting of mitochondria, where it inserts itself into cell membranes. Here, ASX stabilizes membranes and acts as a powerful antioxidant, protecting mitochondria from damage by reactive oxygen species (ROS). ROS are ubiquitous by-products of energy metabolism that must be tightly regulated by cells, lest they bind to and inactivate proteins, DNA and RNA, lipids, and signaling molecules. Most animals cannot synthesize ASX, so they need to acquire it in their diet. ASX is easily thermally denatured during extraction, and its high hydrophobicity limits its bioavailability. Our focus in this review is to contrast the bioactivity of different ASX stereoisomers and how extraction methods can denature ASX, compromising its bioavailability and bioactivity. We discuss the commercial sources of astaxanthin, structure of stereoisomers, relative bioavailability and bioactivity of ASX stereoisomers, mechanisms of ASX bioactivity, evolution of carotenoids, and why mitochondrial targeting makes ASX such an effective antioxidant.
Topics: Animals; Antioxidants; Reactive Oxygen Species; Stereoisomerism; Xanthophylls
PubMed: 35406135
DOI: 10.3390/nu14071522 -
Critical Reviews in Food Science and... 2023Astaxanthin (3,3'-dihydroxy-4,4'-diketo-β-carotene) is a type of C40 carotenoid with remarkable antioxidant characteristics, showing significant application prospects... (Review)
Review
Astaxanthin (3,3'-dihydroxy-4,4'-diketo-β-carotene) is a type of C40 carotenoid with remarkable antioxidant characteristics, showing significant application prospects in many fields. Traditionally, the astaxanthin is mainly obtained from chemical synthesis and natural acquisition, with both approaches having many limitations and not capable of meeting the growing market demand. In order to cope with these challenges, novel techniques, e.g., the innovative cell engineering strategies, have been developed to increase the astaxanthin production. In this review, we first elaborated the biosynthetic pathway of astaxanthin, with the key enzymes and their functions discussed in the metabolic process. Then, we summarized the conventional, non-genetic strategies to promote the production of astaxanthin, including the methods of exogenous additives, mutagenesis, and adaptive evolution. Lastly, we reviewed comprehensively the latest studies on the synthesis of astaxanthin in various recombinant microorganisms based on the concept of microbial cell factory. Furthermore, we have proposed several novel technologies for improving the astaxanthin accumulation in several model species of microorganisms.
Topics: Mixed Function Oxygenases; Oxygenases; Xanthophylls; Carotenoids; Metabolic Engineering
PubMed: 35694786
DOI: 10.1080/10408398.2022.2080176 -
Food & Function Jan 2017Cardiovascular disease is the main contributor to morbidity and mortality worldwide. Based on its unique chemical features, the xanthophyll carotenoid astaxanthin is... (Review)
Review
Cardiovascular disease is the main contributor to morbidity and mortality worldwide. Based on its unique chemical features, the xanthophyll carotenoid astaxanthin is being proposed as a suitable preventive and therapeutic agent in cardiovascular disease. This review focuses on recent advances in astaxanthin research relevant to cardiovascular health and disease, i.e. its direct antioxidant, indirect antioxidant, anti-inflammatory, anti-hypertensive, anti-diabetic, renoprotective, lipid-lowering and anti-atherosclerotic activities in vitro and in vivo. Disparities in the biological activities and health benefits of astaxanthin observed in vitro (strong evidence), in animals (moderate evidence), and in humans (weak evidence) and the variety of astaxanthin sources hamper efforts to establish areas of astaxanthin application in human health care. A list of knowledge gaps and experimental pitfalls is proposed to overcome some of the short-comings in astaxanthin research.
Topics: Animals; Cardiovascular Diseases; Cardiovascular System; Humans; Xanthophylls
PubMed: 27924978
DOI: 10.1039/c6fo01721e -
Biotechnology Advances Nov 2020Although biotechnologies for astaxanthin production from Haematococcus pluvialis have been developed for decades and many production facilities have been established... (Review)
Review
Although biotechnologies for astaxanthin production from Haematococcus pluvialis have been developed for decades and many production facilities have been established throughout the world, the production cost is still high. This paper is to evaluate the current production processes and production facilities, to analyze the R&D strategies for process improvement, and to review the recent research advances shedding light on production cost reduction. With these efforts being made, we intent to conclude that the production cost of astaxanthin from Haematococcus might be substantially reduced to the levels comparable to that of chemical astaxanthin through further R&D and the future research might need to focus on strain selection and improvement, cultivation process optimization, innovation of cultivation methodologies, and revolution of extraction technologies.
Topics: Biotechnology; Microalgae; Xanthophylls
PubMed: 32711005
DOI: 10.1016/j.biotechadv.2020.107602 -
Journal of Pediatric Urology Feb 2022
Topics: Humans; Male; Spermatic Cord Torsion; Testis; Xanthophylls
PubMed: 34776362
DOI: 10.1016/j.jpurol.2021.10.019 -
Bioresource Technology Sep 2019Haematococcus pluvialis is one of the most abundant sources of natural astaxanthin as compared to others microorganism. Therefore, it is important to understand the... (Review)
Review
Haematococcus pluvialis is one of the most abundant sources of natural astaxanthin as compared to others microorganism. Therefore, it is important to understand the biorefinery of astaxanthin from H. pluvialis, starting from the cultivation stage to the downstream processing of astaxanthin. The present review begins with an introduction of cellular morphologies and life cycle of H. pluvialis from green vegetative motile stage to red non-motile haematocyst stage. Subsequently, the conventional biorefinery methods (e.g., mechanical disruption, solvent extraction, direct extraction using vegetable oils, and enhanced solvent extraction) and recent advanced biorefinery techniques (e.g., supercritical CO extraction, magnetic-assisted extraction, ionic liquids extraction, and supramolecular solvent extraction) were presented and evaluated. Moreover, future prospect and challenges were highlighted to provide a useful guide for future development of biorefinery of astaxanthin from H. pluvialis. The review aims to serve as a present knowledge for researchers dealing with the bioproduction of astaxanthin from H. pluvialis.
Topics: Chlorophyceae; Ionic Liquids; Plant Oils; Xanthophylls
PubMed: 31178260
DOI: 10.1016/j.biortech.2019.121606