EXPLORATION OF LOCAL MICROBES FROM WEST JAVA ROBUSTA COFFEE CHERRIES

• Main Author: Niryana Ravila, Alvira
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/62342
• Institution: Institut Teknologi Bandung

Indonesia is the world's fourth largest coffee producer after Brasil, Vietnam and Colombia, contributing about 7% of total world production. Coffee production in Indonesia is dominated by Robusta, which is around 72%, while the remaining 27% is Arabica. However, Robusta coffee produced generally has a lower cupping value than Arabica coffee. Coffee quality is influenced by various things, including the microorganisms involved in the coffee fermentation process. This study aims to determine the abundance of bacteria and yeast from Robusta coffee cherries originating from several areas in West Java, namely the Subang, Bogor and Ciamis areas. Various studies have shown that the main source of microorganisms in the coffee postharvest process is natural microbes derived from coffee cherries. Therefore, this study isolated microbes from fresh coffee cherries, and further measured the abundance of bacterial and yeast groups of bacteria. Measurement of microbial abundance and isolation was carried out by growing microbes on NA, PDA, YGCA, R2A, MRSA, and Actinomycetes Isolation Agar media following the SP-SDS (single plate-serial dilution spotting) method, followed by purification following the fourway streak plate method. The single isolates were characterized macroscopically and microscopically and identified by MALDI-TOF MS. Microbial abundance of fresh coffee cherries from Subang, Bogor and Ciamis on NA, YGCA, PDA, R2A, MRSA, and Actinomycetes Isolation Agar media, respectively, were 9,42x106 CFU/g, 1,12x105 CFU/g, 6,89x106 CFU/g, 7,50x106 CFU/g, 1,98x105 CFU/g, 3,06x106 CFU/g; 3,90x105 CFU/g, 1,07x105 CFU/g, 1,03x103 CFU/g, 4,08x105 CFU/g, 8,00x104 CFU/g, 1,69x105 CFU/g; 1,05x103 CFU/g, 4,08x102 CFU/g, 8,96x102 CFU/g, 1,04x103 CFU/g, 1,03x103 CFU/g, 3,63x102 CFU/g. Isolation by growing microbes in various media above, obtained isolates of bacteria and yeast from Robusta coffee cherries Subang, Bogor, and Ciamis respectively, are 9 bacterial isolates (8 Gram positive and 3 Gram negative) and 1 yeast isolate; 6 isolates of Gram positive bacteria and 2 isolates of yeast; 8 bacterial isolates (5 Gram positive vi and 3 Gram negative) and 1 yeast isolate. The next research stage is the determination of microbial diversity using the Shannon, Gini–Simpson's index, and evenness. The Shannon, Gini–Simpson's, and evenness index values of Robusta Subang respectively are 1.934, 0.841 and 0.839; Robusta Bogor are 2,015, 0.859 and 0.969; Rosbuta Ciamis are 1.755, 0.813 and 0.798. Characterization with MALDI-TOF succeeded in identifying 8 different isolates from Subang, namely Klebsiella pneumoniae, Enterobacter cloacae, Serratia marcescens, Micrococcus luteus, Klebsiella aerogenes, Enterobacter hormaechei, Klebsiella variicola, Candida krusei; 4 different isolates from Bogor, namely Streptococcus gallolyticus, Moraxella osloensis, Enterobacter cloacae, Kloeckera apiculata; and 4 different isolates from Ciamis, namely Klebsiella oxytoca, Bacillus cereus, Micrococcus luteus, Kloeckera apiculata. This study shows that there is diversity in Robusta coffee cherries isolated from the Subang, Bogor and Ciamis.