Collection of Soil Actinomycetes from Cheju Island and Screening for their Antibacterial Activities

제주도 토양방선균의 수집과 항균물질 생산균의 선별

  • Chung, Wan-Seok (Department of Food Science and Engineering, College of Engineering, Cheju National University) ;
  • Kim, Chang-Jin (Korea Research Institute of Bioscience and Biotechnology) ;
  • Ko, Young-Hwan (Department of Food Science and Engineering, College of Engineering, Cheju National University)
  • 정완석 (제주대학교 공과대학 식품공학과) ;
  • 김창진 (생명공학연구소) ;
  • 고영환 (제주대학교 공과대학 식품공학과)
  • Published : 1999.05.31

Abstract

Soil actinomycetes of 703 strains were isolated from 25 sampling points in Cheju Island using 4 different media. Arginine glycerol salts agar containing soil extract was found to be the best medium for the isolation of soil actinomycetes. Soil samples from pasture land showed higher population and diversity of the actinomycetes than those from citrus field, forest, island, hill or valley. When the antibacterial activity of the 526 isolates was tested against three bacterial strains, Escherichia coli, Staphylococcus aureus and Pseudomonas solanacearum the frequency of the isolates with antibacterial activity varied much depending upon the media used for isolation and cultivation. BL106Ba, one of the 10 isolates that showed antibacterial activity against all the above 3 test strains, was chosen based upon the pH and heat stability of its antibacterial metabolites, and was identified as Streptomyces sp. based upon its cultural, morphological and physiological characteristics. The partially purified white crystalline substance obtained from the culture supematant of BL1063a through cation exchange chromatography(AG MP-50) and three times consecutive gel filtration(Sephadex G-10) showed high antimicrobial activity against gram positive and negative bacteria, but low activity against yeasts. The partially purified substance was found to contain at least four different compounds with antibacterial activity by both thin layer chromatography and high performance liquid chromatography.