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 × 106 CFU/g, and that of C. canephora pulp waste was 1.5 ± 1.5 × 106 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. .

Aims: The objective of this research was to isolate caffeine-degrading bacteria from coffee pulp waste in Indonesia andcharacterize their caffeine degradation activity.Methodology and results: The caffeine-degrading bacteria were isolated from coffee pulp wastes of Coffea arabicaand C. canephora. These isolates were selected based on their caffeine degradation activity. The identification andbiochemical properties of the best isolate were conducted via 16S rDNA sequence analyses and by using the Microbactkit. Meanwhile, caffeine degradation activity of this bacteria was analyzed by using LC-MS/MS. The results indicatedthat fourteen bacterial isolates were able to degrade caffeine. The highest caffeine degradation activity was performedby isolate KRM9 at the rate of 99.26 ± 0.01%, on a caffeine medium after 24 h of incubation. Based on the 16S rDNAanalyses, the KRM9 isolate was identified as Pseudomonas monteilii. Till present, this species has not been reported asa caffeine-degrading bacterium. However, LC-MS/MS analysis indicated that caffeine was degraded by P. monteiliiKRM9 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 ofcaffeine-degrading bacteria. This bacterium can be introduced as an agent to degrade caffeine from coffee pulp waste. Itis expected that further research can be conducted on the overall mechanism of caffeine degradation by P. monteiliiKRM9