Determination of yeast diversity in fermented Sumbawa mare’s milk using internal transcribed spacers (ITS) fragment analysis

ABSTRACT

Aims@#Molecular identification of yeast has been conducted on various fermentation products. However, the identification of yeast in fermented Sumbawa mare’s milk based on the genotyping method has not been carried out. This study was aimed to determine the diversity profile of yeasts in fermented Sumbawa mare’s milk using phenetic characters and PCR-RFLP analysis technique based on the ITS region.@*Methodology and results@#Yeast isolates were phenotypically characterized and visualized in a dendrogram using CLAD97 software. Then, the yeast DNA was extracted using heat treatment and amplified using ITS1 and ITS4 primers. The amplicons were analyzed by RFLP using HindIII and HaeIII enzymes. The phylogenetic tree was constructed using MEGA 7.0. Based on the result of grouping by phenetic analysis and PCR-RFLP, the 12 isolates were divided into four groups with different members. The results of the phenetic analysis were divided into group I (all isolates of Dompu), group II (isolate B3, B4, S3), group III (isolate B5) and group IV (isolate S1). The types of yeast that were identified molecularly and represented each group of PCR-RFLP results included in group I were Kluyveromyces marxianus D1A and K. marxianus D1B, group II: K. marxianus D7, group III: Kazachstania humilis D4, while milk from Bima and Sumbawa has one yeast species as a member of group IV, namely Pichia kudriavzevii B3. Kluyveromyces marxianus was the yeast frequently found in Sumbawa fermented mare’s milk.@*Conclusion, significance and impact of study@#Various yeast species as a consortium of the milk samples can contribute to the increasing quality of fermented Sumbawa mare’s milk.