Catenarin Production by Isolates of Pyrenophora tritici-repentis (Died.) Drechsler and its Antimicrobial Activity

A total of 88 Pyrenophora tritici-repentis (Died.) Drechsler isolates from different hosts and localities were screened for catenarin production using thin layer chromatography. Catenarin was detected in 29% of the tested strains. The level of this compound ranged from 2 to 400 ppm and was especially high in case of fungus variants unable to biosynthesize melanins. The extracted pigment exhibited antibiotic properties against Gram-positive bacteria (Aureobacterium liquefaciens, Arthrobacter globiformis, Bacillus brevis, B. circulans, B. subtilis and Curtobacterium plantarum). Catenarin also inhibited the growth of fungi accompanying P. tritici-repentis during the saprophytic phase of development. The most sensitive species was Epicoccum nigrum, whose growth was inhibited up to 90%.