Antagonist effect of volatile organic compounds produced by Debaryomyces hansenii on Colletotrichum gloeosporoides as anthracnose reason of tropical apples

The usage antagonist yeast for biological control had emerged as one of the most promising alternatives in pre and postharvest protection of apples in Indonesia. The aim of the research was to identify volatile organic compounds (VOCs) produced by Debaryomyces hansenii that inhibited the growth of Colletotrichum gloeosporioides, pathogenic fungi of tropical apples. D. hansenii was isolated from apples in Indonesian. Bioassay using potato-dextrose agar medium in sealed petri dishes showed that the fungi growth inhibition was ultimately due to volatile organic compounds produced by D. hansenii. The VOCs were trapped on activated charcoal prior to analyzing by integrated thermal desorption using GC-MS. The VOCs significantly inhibited the mycelia growth of C. gloeosporioides by 85.07 %, and induced morphological abnormalities such as mycelia deviations. The identified VOCs include acids, esters, ketones, oximes, heterocyclic, and phthalate compounds. The result indicated that tropical apple yeast is abundant resources of bioactive VOCs and played an important role in reducing apple anthracnose disease of tropical apples in Indonesia