African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5211

Full Length Research Paper

Isolation and characterization of a novel streptomyces strain Eri11 exhibiting antioxidant activity from the rhizosphere of Rhizoma Curcumae Longae

Kai Zhong1, Xia-Ling Gao1, Zheng-Jun Xu1*, Li-Hua Li1, Rong-Jun Chen1  Xiao-JianDeng1, Hong Gao2, Kai Jiang1,3 and Isomaro Yamaguchi3 
1Research Institute, Sichuan Agricultural University, Wenjiang 611130, P.R., China. 2College of Light Industry, Textile and Food Engineering, Sichuan University, Chengdu 610065, P.R., China. 3Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan.
Email: [email protected]

  •  Accepted: 10 May 2011
  •  Published: 04 June 2011



In the present study, the phylogenetic analysis of the Streptomyces strain Eri11 isolated from the rhizosphere of Rhizoma Curcumae Longae and the antioxidant activity of the broth cultured with Eri11 were investigated. Analysis of 16S rDNA gene sequences demonstrated that the strains Eri11 was most closely related to representatives of the genera Streptomyces. The total phenols and flavonoids contents in cultured broth were detected to be 13.59 ± 0.17 mg gallic acid equivalent/g and 9.93 ± 0.83 mg rutin equivalent/g, respectively. The cultured broth showed the antioxidant activity against the ABTS (2,2’-Azinobis-3-ethyl benzthiazoline-6-sulfonic acid) free radicals and hydroxyl free radicals with IC50 (The half-inhibitory concentration) of 223.81 ± 24.50 μg/ml and 582.42 ± 83.10 μg/ml respectively. So, it was suggested that the isolated Streptomyces strain Eri11 could be a candidate for the nature resource of the antioxidants.

Key words: Streptomyces, phylogeny, cultured broth, antioxidant activity.