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Takaichi S.,Nippon Medical School | Maoka T.,Research Institute for Production Development
Biotechnology Letters | Year: 2015

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 | Year: 2011

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 | Year: 2011

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 | Year: 2012

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

Yamano Y.,Kobe Pharmaceutical University | Maoka T.,Research Institute for Production Development | Wada A.,Kobe Pharmaceutical University
Marine Drugs | Year: 2014

In order to determine the absolute configuration of naturally occurring alloxanthin, a HPLC analytical method for three stereoisomers 1a-c was established by using a chiral column. Two authentic samples, (3S,3?S)- and meso-stereoisomers 1b and 1c, were chemically synthesized according to the method previously developed for (3R,3?R)-alloxanthin (1a). Application of this method to various alloxanthin specimens of aquatic animals demonstrated that those isolated from shellfishes, tunicates, and crucian carp are identical with (3R,3?R)-stereoisomer 1a, and unexpectedly those from lake shrimp, catfish, biwa goby, and biwa trout are mixtures of three stereoisomers of 1a-c. © 2014 by the authors; licensee MDPI. Source

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