În studiul de faţă s-a realizat screeningul a 21 tulpini de micromicete (Penicillium) din Colecţia Naţională deMicroorganisme non-patogene de la Institutul deMicrobiologie alAcademiei de Ştiinţe aMoldovei pentru a se deterimina acţiunea antimicrobiană a acestora faţă de agentul patogen al locii americane Paenibacillus larvae. Tulpinile testate au fost izolate din probele de sol prelevate din zona centrală a Moldovei. Ca mediu nutritiv pentru izolareamicromicetelor a servit malţ-agarul şimediulCzapek. Cultivareamicromicetelor s-a efectuat în termostat, la temperatura de 28oC, timp de 14 zile. Din cele 21 de culturi testate, numai 6 tulpini posedă proprietăţi antibacteriene faţă de Paenibacillus larvae, diametrul zonei de inhibiţie a patogenului variind între 10.2 ± 1.1 mm şi 2.5 ± 2.31. Pentru cercetările ulterioare au fost selectate 2 tulpini, care posedă cea mai intensă activitate antimicrobiană. Diametrul zonei de inhibiţie a patogenului Paenibacillus larvae la tratarea cu exometaboliţi ai acestor tulpini constituie 22-23 mm, ceea ce este echivalent cu acţiunea antibioticului neomicina.

The aimof our investigations was to make the screening of 21 strains of micromycetes (Penicillium) fromthe NationalCollection ofNonpathogenicMicroorganisms of the Institute ofMicrobiology and Biotechnology of the Academy of Sciences of Moldova, in order to establish their antimicrobial effect on the causal agent of American foul brood Paenibacillus larvae. The tested strains were isolated from soil samples taken from the central region of the Republic of Moldova. Malt agar and Czapek medium served as nutrient mediums for the isolation of micromycetes.Micromycetes cultivationwas carried out in the thermostat at the temperature of 28oC for 14 days. Out of the 21 tested cultures, only 6 strains possessed high antibacterial properties against Paenibacillus larvae, the diameter of inhibition zone of the pathogen ranging from10.2 ± 1.1mmto 2.5 ± 2.31mm. Two strains possessing the most intense antimicrobial activity were selected for subsequent investigations. The diameter of the inhibition zone of Paenibacillus larvae when treated with exometabolites of this two strains constituted 22-23 mm, which is equivalent to the effect of neomycin.