The productivity of cocoa plants in Sumbermanjing District is lower than in other parts of Malang Regency. Diseases like pathogenic fungi are to blame for the low output of cocoa plants. This research aimed to find chitinolytic bacteria that were superior at degrading chitin and limiting the growth of pathogenic fungi. These bacteria were isolated from cocoa garden soil and shrimp shell dumps. The bacteria from soil samples taken from the shrimp shell dump in Ujungpangkah District and the cocoa gardens in Sumbermanjing District were cultivated on an agar medium supplemented with colloidal chitin. The pathogenic fungi were discovered from decaying cocoa pods from Sumbermanjing District cocoa plantations. An antagonist test was used to gauge the inhibitory power, and a semi-quantitative test was used to measure the chitinolytic index. The similarity of 16S rDNA sequences allowed for the identification of superior bacterial isolates. The T2S1 isolates of chitinolytic bacteria had the highest levels of pathogenic fungi inhibition (25.14%, 20.85%, and 25.24%). With a 16S rDNA sequence similarity of 99.77%, Bacillus subtilis C10 was identified as the bacterium T2S1.

Cellulase is one of the most widely used enzymes in the industrial world and wastes decomposition process. Bacillus cereus is one of the bacteria that can produce cellulase enzymes that can hydrolyze cellulose to glucose. The addition of cofactors and incubation time can help determine the optimum conditions needed by cellulase enzymes to work optimally. This study aims to determine the effect of adding Mn2+ metal ions and incubation time to the activity of cellulase enzymes from Bacillus cereus endophytic bacteria. This research is experimentally used a Completely Randomized Design (CRD) factorial design with two factor treatments and 3 times repetitions. The first factor is variation of addition Mn2+ metal ions which are 5 mM, 10 mM, and 15 mM, the second is variation of incubation time which are 1 hour, 2 hours, 3 hours, 4 hours, and 5 hours. The data were analyzed using Analysis Of Variance (ANOVA) and if the data significantly affected the parameter, then it would be continued by Duncan Multiple Range Test (DMRT) with the fault level of 5%. The result showed that the interaction of addition Mn2+ metal ions and incubation time affected the cellulase enzyme activity of Bacillus cereus from endophytic bacteria. The highest cellulase enzyme activity obtained from interaction addition Mn2+ metal 10 mM and incubation time 3 hours with an activity 0,335 U/mL, while the lowest cellulase enzyme activity obtained from interaction addition Mn2+ metal 15 mM and incubation time 5 hours with an activity of 0,073 U/mL