[Identification of endophytic Actinomycete Lj20 from plant and its antifungal substances].
OBJECTIVE
Endophytic actinomycete Lj20 with antifungal activity was isolated from the roots of capsicum plants. We identified Lj20 and synthesized its antifungal substances.


METHODS
Morphological, biological and biochemical characteristics, chemotaxonomy analysis and 16S rDNA sequences were used to identify Lj20. According to GC-MS extrapolation result, one of antifungal substances in the metabolites of Lj20 was chemically synthesized. The bioactivities were determined by mycelium growth inhibition method.


RESULTS
Lj20 belonged to Streptomyces sp. and was similar to Streptomyces rochei. The metabolites contained butylated hydroxytoluene and 3, 5-di-tert-butyl-4-hydroxybenzyl methyl ether. The median effective concentration (EC50) of these two compounds to Botrytis cinerea Pers. were 237.04 mg/L of the water and 186.48 mg/L of the water, respectively.


CONCLUSIONS
Lj20 was classified as Streptomyces rochei. Butylated hydroxytoluene and 3, 5-di-tert-butyl-4-hydroxybenzyl methyl ether had significant inhibition to the pathogen.
College of Agriculture, Shanxi Agricultural University, Taigu 030801, China. malin1590@yahoo.com.cn
Lin
L
Ma
Hongbing
H
Chen
Jucai
J
Han
Huiping
H
Liu
D039903:Actinobacteria / Q000737:chemistry / Q000302:isolation & purification* / Q000648:ultrastructure; D000935:Antifungal Agents / Q000032:analysis / Q000302:isolation & purification / Q000494:pharmacology*; D020171:Botrytis / Q000187:drug effects; D002212:Capsicum / Q000382:microbiology*; D002473:Cell Wall / Q000737:chemistry; D004269:DNA, Bacterial / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D008401:Gas Chromatography-Mass Spectrometry; D020128:Inhibitory Concentration 50; D008855:Microscopy, Electron, Scanning; D017422:Sequence Analysis, DNA
D000935:Antifungal Agents; D004269:DNA, Bacterial; D004275:DNA, Ribosomal