A chitinase produced by Bacillus licheniformis MB-2 isolated from Tompaso geothermal springs, Indonesia, was purified and characterized. The extracellular enzyme was isolated by successive hydrophobic interaction, anion exchange, and gel filtration chromatographies. The purified enzyme was a monomer with an apparent molecular weight of 67 kDa. The optimal temperature and pH of the enzyme were 70°C and 6.0, respectively. It was stable below 60°C for 2 h and over a broad pH range of 4.0-11.0 for 4 h. The enzyme was resistant to denaturation by urea (1 M), Tween-20 (1%) and Triton-X (1%), but unstable toward organic solvents such as dimethyl sulphoxide, DMSO, (5%) and polyethylene glycol, PEG, (5%) for 30 min. The enzyme hydrolysed colloidal chitin, glycol chitin, chitosan, and glycol chitosan. The first 13 N-terminal amino acids of the enzyme were determined as SGKNYKIIGYYPS, which is identical to those in chitinases from B. licheniformis and B. circulans.

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Production of invert cane syrup is an alternative diversification product from sugarcane. The main problem with this product is the high cost of the associated decolourisation process for producing syrup with attractive colour for the consumer. This research project was conducted to study the effect of raw cane juice colour from different cane varieties on the colour of clear juice after purification and decolourisation steps as part of the process for the production of invert cane syrup. Purification of the raw cane juice was conducted using carbonatation-phosphatation followed by decolourisation of the clear juice using powder activated carbon (PAC). Sugarcane varieties were grouped into high, medium and low colour varieties having raw cane juice colour [20,000, 10,000-20,000 and \10,000 IU, respectively. The correlation between raw cane juice colour and clear juice colour after the purification and decolourisation processes was very high. The colour of clear juice after purification followed by decolourisation using PAC at 1.6% on brix using high, medium and low colour cane varieties were 4,500, 2,100 and 680 IU, respectively. In order to get the same colour as clear juice from low colour cane varieties, additional decolourisation processing was needed for clear juice from the high colour cane varieties. This investigation was able to show that using selective low colour sugarcane varieties in the production of invert cane syrup minimised the cost of decolourisation.