Effects of non-starch polysaccharides enzyme, phytase and citric acid on activities of endogenous digestive enzymes of tilapia (Oreochromis niloticus × Oreochromis aureus)

Abstract

Non-starch polysaccharides (NSPs) enzyme, phytase and citric acid have been shown to increase digestibility in pigs, poultry and some fish. To examine their roles in digestion in tilapia (Oreochromis niloticus · Oreochromis aureus), the present study was designed to evaluate their effects on activities of a number of endogenous digestive enzymes in tilapia. Neither NSPs enzyme (1 g kg )1 ) nor phytase (1 g kg )1 ) affected the activities of protease in digestive organs. In contrast, NSPs enzyme increased the activities of amylase in the hepatopancreas and intestine by 11.4% and 49.5%, respectively, while phytase (1 g kg )1 ) increased the activities of amylase in the hepatopancreas and intestine by 14.0% and 24.1%, respectively. Citric acid (10 g kg )1 ) increased the activities of protease in stomach by 29.6%, but reduced the activities of protease in the intestine by 35.1%. Citric acid increased the activities of amylase in the hepatopancreas and intestine by 30.7% and 29.4%. Lipase activities were not affected by NSPs enzyme, phytase or citric acid. Above results suggest that NSPs enzyme, phytase and citric acid primarily influence the activities of amylase in digestive tract of tilapia. KEY WORDS

Non-starch polysaccharides and their role in fish nutrition – A review

“…Almirall et al (1995) showed that broiler chicks fed with high viscosity barley had lower amylase and lipase activities in the digesta, while addition of b-glucanase in the diet increased activities of the two enzymes and of trypsin as well. This observation was consistent with the result of Li, Li, and Wu (2009) with tilapia (Oreochromis niloticus  Oreochromis aureus) where 1 g/kg of NSP-degrading enzyme (50 FBG (fungal b-glucanase units)/g; Roche Shanghai) increased activity of amylase in the hepatopancreas and intestine by 11.4% and 49.5%, respectively. The application of Natugrain-blend Ò (containing b-glucanase and b-xylanase) at concentrations of 75, 150 and 300 ll/kg in diets containing 30% wheat or dehulled lupin had no remarkable effect on dry matter, energy or protein digestibilities when fed to silver perch (Stone, Allan, & Anderson, 2003a).…”

Efeito da suplementação de fitase na alimentação de juvenis de tambaqui (Colossoma macropomum)

“…Em peixes onívoros, esse mecanismo é reduzido, devido ao valor do pH do estômago dessas espécies. Como alternativa, poderiam ser utilizados ácidos orgâ-nicos ou acidificantes na dieta para melhorar a atividade enzimática (Li et al, 2008).…”

Effect of dietary L-malic acid supplementation on growth, feed utilization and digestive function of juvenile GIFT tilapiaOreochromis niloticus(Linnaeus, 1758)

“…The Genetically Improved Farmed Tilapia (GIFT) strain of O. niloticus was developed by the International Center for Living Aquatic Resources Management (ICLARM) from selected breeding stocks from Africa and Asia (Tendencia et al., ), and has been widely cultured in China in recent years. To our knowledge, dietary inclusion of citric acid at 10 g kg −1 improved the digestive function of hybrid tilapia O. niloticus × O. aureus (Li et al., ). As another intermediate metabolite of the TCA cycle, dietary MA inclusion might exert similar beneficial effects in tilapia.…”