Cellulolytic Aspergillus Isolate Compost Production

The isolate of Aspergillus sp. (Bioggp 3) was obtained from a previous study in which they were isolated from the isolation process of mixed leaf litter and soil taken from the pineapple plantation of PT. Great Giant Pineapple (PT. GGP) Terbanggi Besar, Central Lampung, Indonesia. The isolate showed cellulolytic and xylanolytic activity with a cellulolytic index 4.00 ± 0.783 and xylanolytic index 4.20 ± 1.03 respectively [16] (link). The compost material used is pineapple plant biomass which consists of leaves and stems. The selection of cellulolytic fungi isolates was done by modification of the Congo-Red method [17] (link). Isolates were obtained were cultured in Cellulose Agar (cellulose 5.0, NaNO₃ 1.0, K₂HPO₄ 1.8, MgSO₄.7H₂O 0.9, KCl 0.5, 0.5 yeast extract, casein hydrolysat 0.5, agar 20 and distilled water 1L). Confirmation of cellulose-degrading ability of fungal isolates was performed by streaking it on cellulose agar media. Media were 2 layer media (bilayer) with the bottom layer was a PDA of 1/5 recipes, agar 1.5, and distilled water 100 mL. The top layer was Carboxymethyl Cellulose (CMC) 1–2%, agar 1.5 and distilled water 100 mL. Once inoculated with fungi in the middle of the test media, the cultures were then incubated for 4 days [18] . The media were added with 0.1% Congo-Red and allowed to stand for 20 minutes at room temperature. Media was washed with 1 M NaCl. Isolates producing cellulase formed a halo (clear zone) around the colony. The use of Congo-Red as an indicator for cellulose degradation in an agar medium provides the basis for a rapid and sensitive screening test for cellulolytic fungi. Colonies showing decolorization of Congo-Red were taken as positive cellulose-degrading fungal colonies [7] (link), and only these were taken for further study. The production of Aspergillus sp. inoculum was carried out in the Microbiology Lab, while composting applications were conducted at the Green House Botany Laboratory, Department of Biology, Universitas Lampung. Compost chemical analysis was carried out at PT. GGP.