Biotechnology Bulletin ›› 2015, Vol. 31 ›› Issue (2): 84-90.doi: 10.13560/j.cnki.biotech.bull.1985.2015.02.012

• Research Report • Previous Articles     Next Articles

Screening a New Type of Schizochxtrium Strain Producing DHA Using Starch by Protoplast Fusion Technology

Wang Di1, Lu Fuping1, Wang Haijun1, Li Demao2, Chen Shulin2, Zhang Ke2   

  1. 1. College of Biotechnology,Tianjin University of Science & Technology,Tianjin 300457;
    2. Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering,Tianjin Institute of Industrial Biotechnology,Chinese Academy of Sciences,Tianjin 300308
  • Received:2014-07-28 Online:2015-02-05 Published:2015-02-06

Abstract: Schizochxtrium B4D1 and Aspergillus niger CGMCC 3.316 as original strains, a new strain of Schizochxtrium was selected using starch for producing DHA. The protoplasts from two parents strains were obtained respectively with Lysing enzyme. The study was investigated on the effect of culture time, culture method, enzymolysis time on the protoplasts preparation. Finally, the protoplasts fusion was done under the PEG mediated condition. The optimum condition of protoplast fusion was as follows:PEG6000 concentration of 40%, fusion temperature of 30℃, fusion time of 10 min. Furthermore, the fusion rate reached 1.9% at the optimum condition. Through comparing its colony characteristics, color, morphology and purified spore culture, a new strain has been selected using starch as carbon source. RAPD verification showed that the fusant having integrated genome of B4D1 and CGMCC 3.316 expressed more genetic information from B4D1.

Key words: Schizochytrium, DHA, protoplast, fusion, starch