Aims:The objective of this research was to isolate caffeine-degrading bacteria from coffee pulp waste in Indonesia and characterize their caffeine degradation activity. Methodology and results: The caffeine-degrading bacteria were isolated from coffee pulp wastes of Coffea arabica and C. canephora. These isolates were selected based on their caffeine degradation activity. The identification and biochemical properties of the best isolate were conducted via 16S rDNA sequence analyses and by using the Microbact kit. Meanwhile, caffeine degradation activity of this bacteria was analyzed by using LC-MS/MS. The results indicated that fourteen bacterial isolates were able to degrade caffeine. The highest caffeine degradation activity was performe d by isolate KRM9 at the rate of 99.26 ± 0.01%, on a caffeine medium after 24 h of incubation. Based on the 16S rDNA analyses, the KRM9 isolate was identified as Pseudomonas monteilii. Till present, this species has not been reported as a caffeine-degrading bacterium. However, LC-MS/MS analysis indicated that caffeine was degraded by P. monteilii KRM9 and theobromine was not the secondary metabolite of caffeine degradation. Conclusion, significance and impact of study: Pseudomonas monteilii KRM9 was detected as a new isolate of caffeine-degrading bacteria. This bacterium can be introduced as an agent to degrade caffeine from coffee pulp waste. It is expected that further research can be conducted on the overall mechanism of caffeine degradation by P. monteilii KRM9.

Aims:The objective of the research was to get the potential cellulolytic bacteria which was caffeine tolerance from Indonesian coffee pulp waste. Methodology and results: The cellulolytic bacteria were isolated from coffee pulp wastes of Coffea arabica and C. canephora. These isolates were selected based on their cellulose hydrolysis, CMCase activity, and caffeine tolerance. The density of cellulolytic bacteria of C. arabica pulp waste was 4.7 ± 3.5 × 10 6 CFU/g, and that of C. canephora pulp waste was 1.5 ± 1.5 × 10 6 CFU/g. Among 61 cellulolytic bacterial isolates, 24 isolates formed clear zones on CMC medium with Gram iodine flooding. Three isolates (CRM10, CRM1, and CRM12) from C. canephora pulp waste had the highest cellulolytic activity. Based on the CMCase activity, it was indicated that an isolate of CRM10 showed the highest CMCase activity with 3.38 ± 0.65 U/mL. This bacteria had tolerance ability to caffeine until 0.4% on nutrient agar medium. Isolates of CRM10 had similarity to Bacillus subtilis based on 16S rDNA sequence. Conclusion, significance, and impact of study: CRM10 was identified as Bacillus subtilis and considered as a potential isolate to degrade cellulose of coffee pulp waste that contained caffeine. .

Naturally, the coffee pulp contains caffeine. Caffeine-degrading bacteria can use caffeine for their growth. The purpose of this research was to obtain high potency of caffeine-degrading bacterial isolates. These bacteria were isolated from naturally-fermented pulp waste of Coffea arabica. The bacteria were isolated by using minimal medium M9 contain 1 g/L caffeine and was screened based on their activity to degrade caffeine. There 13 isolates that successfully isolated by this medium. The research found five isolates had high potency to degrade caffeine. They were KAFS 33, KAFS 34, KAFS 16, KAFS 47, and KAFS 35 respectively. Those isolates were the potential to be further analysis as an agent of decaffeinating coffee.