Document Type : Primary Research paper
A study was undertaken to evaluate the effects of supplementation fibrolytic enzymes on digestibility to improving the nutritional quality of local raw materials (soybean meal, rice bran, cassava pulp, cassava skin) for aquafeed. The objectives of the study were to improve the quality of cassava pulp and cassava skin from industrial cassava starch production by fibrolytic enzymes to obtain more sugar that can be the energy source in aquatic animals feed.The factorial experimental design (4X3) was conducted to study 4 types of raw materials (soybean meal, rice bran, cassava pulp, cassava skin) and 3 types of enzymes (xylanase at 24,000 U/kg, cellulase at 10 U/kg and mannanase at 750 U/kg). The result found that total sugars (glucose, xylose, maltose, mannose) from in vitro digestion from rice bran digestion was the highest (6.477 ± 107 mg/g) and significant differences from other raw materials (P < 0.05). However, total sugars of cassava pulp (0.900 ± 0.031 mg/g) and cassava skin (0.543 ± 0.013 mg/g) was not significantly difference from soybean meal (1.459 ± 0.054 mg/g) (P > 0.05). In soybean meal, rice bran and cassava pulp all three enzymes showed no significant differences (P > 0.05) in digestibility efficiency interestingly, cellulase exhibited significantly better digestibility with cassava skin. Total sugar from Cellulase, Xylanase and Mannanase were 0.484 ± 0.215, 0.128 ± 0.025 and 0.287 ± 0.055 respectively. Mannanase enzyme had the ability to digest fiber and released sugar from cassava pulp better than cellulase enzyme and xylanase enzyme, respectively.