Source: SEAMEO BIOTROP's Research Grant | 2019
Yeasts and bacteria are two of biocontrol agents can be used to control mycotoxigenic fungi, while the mangosteen grind is used as medicine products because it contain xanthone component. Xanthone has benefit for antibacteria, antioxidant, antiproliferation, antiinflamation, antimicrobe, antitumor, and anticancer.Yeasts and bacteria also can stimulate the fermentation process. Using the combination of yeast, acetic acid bacteria (AAB) and mangosteen grind extract (MGE) to inhibit aflatoxigenic Aspergillus flavus has never been conducted before. The objectives of this research were to investigate the effects of yeasts, AAB, and mangosteen grind extract on the growth of aflatoxigenic A. flavus in vitro; and to get information on the type of interactions between yeast and aflatoxigenic A. flavus. As much as 4 yeast isolates, i.e 3 yeast isolates of Issatchenkia orientalis (BIO 211291, BIO 211286, BIO 211288) and 1 isolate of Endomyces fibuliger BIO 132219; and 1 isolate of Acetobacter aceti FNCC0016 were tested for their antagonistic properties against aflatoxigenic A. flavus BIO 3361/747 . The percentage of inhibition and type of interaction were tested using direct oposition and screening for antagonistic yeast on aflatoxigenic A. flavus was also conducted using well (dip) test method. Three of four yeast isolates (2 isolates of Issatchenkia orientalis BIO 211291 and BIO 211288, and 1 isolate of Endomyces fibuliger BIO 132219) were able to inhibit aflatoxigenic A. flavus. The highest percentage of inhibition were found in I. orientalis BIO 211291 (49.58%) and E. fibuliger BIO 132219 (49.29%). Interaction between I. orientalis BIO 211291 and I. orientalis BIO 211288 on aflatoxigenic A. flavus isolates resulted in D type, while the interaction type between I. orientalis BIO 211286 and E. fibuliger BIO 132219 on A. flavus were A. The highest percentage of inhibition using well method (in vitro) was (100%) found in sample with I. orientalis BIO 211288 + Acetobacter aceti + MGE + A. flavus.