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

Aims: Microbial cultures with multi-biological activities in increasing plant growth were developed to be an alternative way to reduce dependency on chemical fertilizer and to support plants productivity. The aims of this study were to characterize the potency of Tangerine var. Batu 55 diazotroph rhizobacteria as Plant Growth Promoting Rhizobacteria (PGPR) agents and to identify diazotroph rhizobacteria with multi-biological activities especially the activity of nitrogen fixation, ammonia (NH3) production, phosphate solubilizing, and Indole Acetic Acid (IAA) production. Methodology and results: A total of 21 nitrogen-fixing bacteria (diazotroph) were isolated from Tangerine rhizosphere soil. Screening of PGPR isolates candidates were performed by in vitro assays consist of phytohormone Indole Acetic Acid (IAA) production, ammonia production, and phosphate-solubilizing assay. Candidates of PGPR isolates were identified based on 16S rDNA sequences. The result revealed that three isolates (Dbs 1, Dbs 2, and Dbm 3) had multibiological activities. Isolates of Dbs 1, Dbs 2, and Dbm 3 capable producing ammonia up to 10 μg/mL; 9.1 μg/mL; and 3.8 μg/mL, activity of IAA production were 30.08 μg/mL; 24.68 μg/mL; and 190.77 μg/mL, activity of phosphate solubilizing were 11.3 μg/mL; 8.6 μg/mL; and 2.2 μg/mL, respectively. Based on 16S rDNA, Dbs 1, Dbs 2, and Dbm 3 were identified as Acinetobacter schindleri, Pseudomonas syncyanea, and P. moraviensis, respectively. Based on our knowledge, this is the first report P. syncyanea was exhibited plant growth-promoting properties. Conclusion, significance and impact of study Candidates of PGPR isolates could be alternative PGPR agents, but still need to evaluate the effect of three PGPR isolates application on citrus plant growth.