In vitro evaluation of nonstarch polysaccharide digestibility of feed ingredients by enzymes

Some of the commonly used feed ingredients for poultry (corn, sorghum, fing er millet, deoiled ricebran, soybean meal, peanut meal, sunflower meal, and rapeseed meal) were screened for pentosans, cellulose, pectin, and total n onstarch polysaccharides. The ingredi ent in vitro digestibilities by enzym es were evaluated. Cereal samples screened contained mainly pentosans. Pect in content was rich in oilseed meals. Sunflower meal, soybean meal, deoiled rice bran, and a broiler starter diet were subjected to a two-stage in vit ro digestion assay with three different enzyme mixtures viz., Enzyme-I (xyl anase + cellulase from Trichoderma viridae), Enzyme-II (xylanase + cellulas e + beta -glucanase from Huminicola insolens), and Enzyme-III (xylanase + c ellulase + pectinase + beta -glucanase from Aspergillus aculeatus) by incub ating 0.1 g of the sample with 3 mL of a pepsin-HCl mixture (2,000 U pepsin /mL of 0.1N HCl) for 45 min to simulate the peptic phase of bird digestion. A pancreatin-NaHCO3 mixture (2 mg pancreatin/mL of 1 M NaHCO3) was used fo r 2 h at 40 C to simulate the pancreatic phase. Digestibility was assessed by measuring the relative viscosity of the digesta supernatent and the tota l sugars released. Enzyme-I produced the least relative viscosity and highe st total sugars in sunflower meal, deoiled rice bran, and broiler starter d iet, whereas Enzyme-III was very effective in soybean meal subjected to in vitro digestion. The assay was a convenient and rapid method of screening f or effective and stable enzymes.