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Takaichi S.,Nippon Medical School | Maoka T.,Research Institute for Production Development
Biotechnology Letters

Objectives: Neurosporene is a carotene and an intermediate in the synthesis of lycopene from phytoene. Its content in carotenogenic organisms is very low; hence, the complete assignments of its spectroscopic data, including NMR, are insufficient. Results: A purple bacterium of Rhodobacter sphaeroides G1C mutant had only one carotenoid. This carotenoid was extracted and purified using silica gel, DEAE-Toyopearl and C18-HPLC columns. It was identified using its absorption spectra, mass spectra, and 1H- and 13C-NMR spectra, including two-dimensional spectral analyses. Conclusion: The major carotenoid in the Rhodobacter sphaeroides G1C mutant was identified as neurosporene (7,8-dihydro-ψ,ψ-carotene) using spectroscopic measurements, including complete assignments of its 1H- and 13C-NMR spectral data. © 2015, Springer Science+Business Media Dordrecht. Source

Maoka T.,Research Institute for Production Development
Marine drugs

Marine animals contain various carotenoids that show structural diversity. These marine animals accumulate carotenoids from foods such as algae and other animals and modify them through metabolic reactions. Many of the carotenoids present in marine animals are metabolites of β-carotene, fucoxanthin, peridinin, diatoxanthin, alloxanthin, and astaxanthin, etc. Carotenoids found in these animals provide the food chain as well as metabolic pathways. In the present review, I will describe marine animal carotenoids from natural product chemistry, metabolism, food chain, and chemosystematic viewpoints, and also describe new structural carotenoids isolated from marine animals over the last decade. Source

Maoka T.,Research Institute for Production Development | Akimoto N.,Kyoto University
Chemical and Pharmaceutical Bulletin

Three new carotenoids: 7′,8′,9′,10′-tetrahydro- β-cryptoxanthin, 7′,8′-dihydrodiatoxanthin, and (3S,6S,6′S)-ε-cryptoxanthin were isolated from the skin, fins, and gonads of the Japanese common catfish, Silurus asotus, as minor carotenoids. Their structures were determined based on chemical and spectroscopic data. Furthermore, 9Z and/or 9′Z geometrical isomers of parasiloxanthin, 7′,8′-dihydroparasiloxanthin, and 7′,8′-dihydro-β- cryptoxanthin were characterized by 1H-NMR. © 2011 Pharmaceutical Society of Japan. Source

Maoka T.,Research Institute for Production Development | Ochi J.,Kinki University | Mori M.,Kinki University | Sakagami Y.,Kinki University
Journal of Oleo Science

The biochemical properties of carotenoids from 2 species of freshwater bivalve, namely, Unio douglasiae nipponensis and Anodonta lauta, and 2 species of freshwater snail, namely, Cipangopaludina chinensis laeta and Semisulcospira libertina, were investigated. Diatoxanthin and fucoxanthin were identified as major carotenoids in both bivalves. In contrast, lutein and zeaxanthin were found to be the major carotenoids in C. chinensis laeta. In addition, a series of keto carotenoids was also identified in S. libertina. © 2012 by Japan Oil Chemists' Society. Source

Takemura M.,Ishikawa Prefectural University | Maoka T.,Ishikawa Prefectural University | Maoka T.,Research Institute for Production Development | Misawa N.,Ishikawa Prefectural University

Main conclusion: MpBHYcodes for a carotene β-ring 3(,3′)-hydroxylase responsible for both zeaxanthin and lutein biosynthesis in liverwort. MpCYP97C functions as an ε-ring hydroxylase (zeinoxanthin 3′-hydroxylase) to produce lutein in liverwort. Abstract: Xanthophylls are oxygenated or hydroxylated carotenes that are most abundant in the light-harvesting complexes of plants. The plant-type xanthophylls consist of α-xanthophyll (lutein) and β-xanthophylls (zeaxanthin, antheraxanthin, violaxanthin and neoxanthin). The α-xanthophyll and β-xanthophylls are derived from α-carotene and β-carotene by carotene hydroxylase activities, respectively. β-Ring 3,3′-hydroxylase that mediates the route of zeaxanthin from β-carotene via β-cryptoxanthin is present in higher plants and is encoded by the BHY (BCH) gene. On the other hand, CYP97A (or BHY) and CYP97C genes are responsible for β-ring 3-hydroxylation and ε-ring 3′-hydroxylation, respectively, in routes from α-carotene to lutein. To elucidate the evolution of the biosynthetic routes of such hydroxylated carotenoids from carotenes in land plants, we identified and functionally analyzed carotenoid hydroxylase genes of liverwort Marchantia polymorpha L. Three genes homologous to higher plants, BHY, CYP97A, and CYP97C, were isolated and named MpBHY, MpCYP97A, and MpCYP97C, respectively. MpBHY was found to code for β-ring hydroxylase, which is responsible for both routes starting from β-carotene and α-carotene. MpCYP97C functioned as an ε-ring hydroxylase not for α-carotene but for zeinoxanthin, while MpCYP97A showed no hydroxylation activity for β-carotene or α-carotene. These findings suggest the original functions of the hydroxylation enzymes of carotenes in land plants, which are thought to diversify in higher plants. In addition, we generated recombinant Escherichia coli cells, which produced rare and novel carotenoids such as α-echinenone and 4-ketozeinoxanthin, through pathway engineering using bacterial carotenogenic genes that include crtW, in addition to the liverwort MpLCYb, MpLCYe and MpBHY genes. © 2014, Springer-Verlag Berlin Heidelberg. Source

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