title: Extract from a mutant Rhodobacter sphaeroides as an enriched carotenoid source.
abstract: BACKGROUND
  The extract Lycogen™ from the phototrophic bacterium Rhodobacter sphaeroides (WL-APD911) has attracted significant attention because of its promising potential as a bioactive mixture, attributed in part to its anti-inflammatory properties and anti-oxidative activity.
  
  
  OBJECTIVE
  This study aims to investigate the components of Lycogen™ and its anti-inflammatory properties and anti-oxidative activity.
  
  
  RESULTS
  The mutant strain R. sphaeroides (WL-APD911) whose carotenoid 1,2-hydratase gene has been altered by chemical mutagenesis was used for the production of a new carotenoid. The strain was grown at 30°C on Luria-Bertani (LB) agar plates. After a 4-day culture period, the mutant strain displayed a 3.5-fold increase in carotenoid content, relative to the wild type. In the DPPH test, Lycogen™ showed more potent anti-oxidative activity than lycopene from the wild-type strain. Primary skin irritation test with hamsters showed no irritation response in hamster skins after 30 days of treatment with 0.2% Lycogen™. Chemical investigations of Lycogen™ using nuclear magnetic resonance (NMR) (1)H, (13)C, and COSY/DQCOSY spectra have identified spheroidenone and methoxyneurosporene. Quantitative analysis of these identified compounds based on spectral intensities indicates that spheroidenone and methoxyneurosporene are major components (approximately 1:1); very small quantities of other derivatives are also present in the sample.
  
  
  CONCLUSIONS
  In this study, we identified the major carotenoid compounds contained in Lycogen™, including spheroidenone and methoxyneurosporene by high-resolution NMR spectroscopy analysis. The carotenoid content of this mutant strain of R. sphaeroides was 3.5-fold higher than that in normal strain. Furthermore, Lycogen™ from the mutant strain is more potent than lycopene from the wild-type strain and does not cause irritation in hamster skins. These findings suggest that this mutant strain has the potential to be used as an enriched carotenoid source.
authors.affiliation: Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung, Taiwan.|Department of Medicine, Kaohsiung Armed Forces General Hospital, Kaohsiung, Taiwan.
authors.forename: Chih-Chiang
authors.initials: CC
authors.lastname: Wang
authors.affiliation: Department of Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan.
authors.forename: Shangwu
authors.initials: S
authors.lastname: Ding
authors.affiliation: Department and Graduate Institute of Aquaculture, National Kaohsiung Marine University, Kaohsiung, Taiwan.
authors.forename: Kuo-Hsun
authors.initials: KH
authors.lastname: Chiu
authors.affiliation: Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung, Taiwan.|Department and Graduate Institute of Aquaculture, National Kaohsiung Marine University, Kaohsiung, Taiwan.|Asia-Pacific Biotech Developing, Inc., Kaohsiung, Taiwan.
authors.forename: Wen-Sheng
authors.initials: WS
authors.lastname: Liu
authors.affiliation: Department of Pharmacy and Graduate Institute of Pharmaceutical Technology, Tajen University, Pingtun County, Taiwan.
authors.forename: Tai-Jung
authors.initials: TJ
authors.lastname: Lin
authors.affiliation: Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung, Taiwan; wzh@mail.nsysu.edu.tw.
authors.forename: Zhi-Hong
authors.initials: ZH
authors.lastname: Wen
keywords: Lycogen™; Rhodobacter sphaeroides; anti-oxidative; carotenoid; methoxyneurosporene; phototrophic bacteria