ANTAGONISTIC EFFECT OF YEAST, ACETIC ACID BACTERIA AND MANGOSTEEN RIND EXTRACT ON AFLATOXIGENIC Aspergifis flaws IN UNFERMENTED COCOA BEANS

Abstract

Yeasts and bacteria are two of common biocontrol agents to control mycotoxigenic fungi. Meanwhile, the mangosteen rind extract contains xanthone and gartanin compounds for antioxidant, antiproliferation,antiinflammation, antimicrobial, and anticancer. The objectives of this research were to test the effects of yeasts,acetic acid bacteria (AAB), and mangosteen rind extract on the aflatoxigenic A.ybegillz1sj7av.w growth and aflatoxinproduction in unfermented cocoa beans. Four yeast isolates, i.e., Issatcbenkia orientalis (lo) BIO 211291, 286 and288, and Endomyces fbulger (E! BIO 132219; one bacteria isolate of Acetobacter aceti (Aa) FNCC0016; andmangosteen rind extract (MRE) were tested for their capabilities in inhibiting an aflatoxigenic A.javus (Afj BIO3361/747 growth using the well method (in vitro). Two types of yeast (10 BIO 211291 and 288) were combinedwith Aa and MRE in cocoa beans (in vivo). Aflatoxin production was analyzed using Thin hyer Cbromathograph_v(TLC). The results showed that interaction of lo BIO 211291 and 288, and EfBIO 132219 on aflatoxigenic Afwere interaction with inhibition zone > 2 mm (type D), while the interaction type of lo BIO 211286 on Afweremutual intermingling growth, where both fungi grew into each other without any macroscopic sign of interaction(type A). The best treatment in agar media (in vitro) was Io BIO 211288 + Aa on Potato Dextrose Agar + 12 g/LMRE. The highest lo population was 5.88 log cfu/g on cocoa beans inoculated by Io BIO 211291 + MRE in 1day after inoculation, while the highest A. aceti population was 4.74 log cfu/g on cocoa beans with lo BIO 21 1291+ BIO 211288 + Aa in 3 days after inoculation. Two best treatments were Io BIO 211288 + Aa + MRE and IoBIO 211291 + BIO 211288 + Aa + MRE, because there were no A.j7avuspopulation since 3 until 11 days afterinoculation. Aflatoxin in all samples treatment was lower than limit detection B1 (< 2.20 ppb), B2 (< 3.50 ppb),(GI < 0.54 ppb), dan (G2 < 1.00 ppb)