Biotechnology Bulletin ›› 2013, Vol. 0 ›› Issue (2): 190-194.

• Research report • Previous Articles     Next Articles

A Modified Method for Quantification of L-lysine

Jiang Anna1,2 Cao Mingfeng2,3 Li Qinggang2,3 Zheng Ping2,3 Yang Hongjiang1 Sun Jibin2,3   

  1. (1. School of Biological Engineering,Tianjin University of Science and Technology,Tianjin 300457 ;2. Tianjin Institute of Industrial
  • Received:2012-07-05 Revised:2013-02-27 Online:2013-02-26 Published:2013-02-27
  • Contact: 孙际宾,男,研究员,博士生导师,研究方向:微生物代谢工程;E-mail :sun_jb@tib.cas.cn

Abstract: A modified method was established to determine lysine concentration using ninhydrin-ferric reagents. Unlike the traditional method which measures the total amino acids, our modification showed high specificity and favorable linearity to lysine(0-200 mmol/L). In our protocol the characteristic absorption at 480 nm was measured after the reaction mixture was boiled for 35 minutes in disodium hydrogen phosphate-citrate buffer at pH2.2. The method not only successfully excludes the interference of impurities including proline, ornithine, glycine, arginine and histidine, but offers the accurate and reliable determination of the lysine in the fermentation broth directly.

Key words: Lysine, Ninhydrin-ferric reagents, Color reaction, Specific detection