Long Wen, Ou Hongdong, Luo Jiajie, Mi Haifeng, Zhang Lu, Deng Junming
College of Fisheries, Guangdong Ocean University, Zhanjiang, China.
Tongwei Agricultural Development Co., Ltd, Chengdu, China.
J Sci Food Agric. 2025 Jun 30. doi: 10.1002/jsfa.70029.
Citrus pulp (CP) is rich in pectin, which exhibits anti-inflammatory, antioxidant, and hypolipidemic properties. Despite these advantages, the application of CP in aquafeed remains limited. This study investigated the effects of dietary CP inclusion on the glucolipid metabolism of largemouth bass (Micropterus salmoides).
Juveniles were fed diets containing varying levels of CP (0%, 3%, 6%, 9%, 12%, or 15%) for 58 days. Adding 3-6% CP in feed has no adverse effect on growth performance. Dietary CP had direct effects on lipid and glucose metabolism. For lipid metabolism, the inclusion of 3-12% CP resulted in reduced serum complement 3, complement 4, total cholesterol and triglyceride levels, as well as low-density lipoprotein cholesterol/high-density lipoprotein cholesterol (LDL-C/HDL-C) ratio. Additionally, the inclusion upregulated the relative expression levels of lipid metabolism-related genes such as ppar-α, cpt-1α, and apoa1, but downregulated the relative expression level of apob in liver. However, higher doses (>12%) of CP led to increased serum LDL-C and HDL-C levels. Regarding glucose metabolism, the inclusion of 3-12% CP enhanced hepatic glucose-6-phosphate dehydrogenase (G6PDH), phosphoenolpyruvate carboxykinase (PEPCK), hexokinase and phosphofructokinase-6 (PFK-6) activities as well as serum insulin, insulin-like growth factor 1, growth hormone, G6PDH, PEPCK, hexokinase and PFK-6 levels. Additionally, the inclusion upregulated the relative expression levels of glucose metabolism-related genes such as glut2, glut4, gk, hk, pk, pfk, pepck, g6pase, fbp1, ir, irs1, and pik3r1 in liver. However, higher doses (>12%) of CP did not improve the indicators of glucose metabolism and even downregulated the relative expression level of irs1.
In summary, the recommended dietary inclusion of CP is between 3% and 12%, as this range can enhance lipid and glucose metabolism in largemouth bass, and the addition of 6% CP had the most beneficial effect on the glucolipid metabolism of largemouth bass. © 2025 Society of Chemical Industry.
柑橘果肉（CP）富含果胶，具有抗炎、抗氧化和降血脂特性。尽管有这些优点，但CP在水产饲料中的应用仍然有限。本研究调查了饲料中添加CP对大口黑鲈（Micropterus salmoides）糖脂代谢的影响。
幼鱼投喂含不同水平CP（0%、3%、6%、9%、12%或15%）的饲料58天。饲料中添加3 - 6%的CP对生长性能无不利影响。饲料CP对脂质和葡萄糖代谢有直接影响。对于脂质代谢，添加3 - 12%的CP可降低血清补体3、补体4、总胆固醇和甘油三酯水平，以及低密度脂蛋白胆固醇/高密度脂蛋白胆固醇（LDL-C/HDL-C）比值。此外，添加CP上调了肝脏中脂质代谢相关基因如ppar-α、cpt-1α和apoa1的相对表达水平，但下调了apob的相对表达水平。然而，较高剂量（>12%）的CP导致血清LDL-C和HDL-C水平升高。关于葡萄糖代谢，添加3 - 12%的CP可增强肝脏葡萄糖-6-磷酸脱氢酶（G6PDH）、磷酸烯醇式丙酮酸羧激酶（PEPCK）、己糖激酶和磷酸果糖激酶-6（PFK-6）的活性，以及血清胰岛素、胰岛素样生长因子1、生长激素、G6PDH、PEPCK、己糖激酶和PFK-6的水平。此外，添加CP上调了肝脏中葡萄糖代谢相关基因如glut2、glut4、gk、hk、pk、pfk、pepck、g6pase、fbp1、ir、irs1和pik3r1的相对表达水平。然而，较高剂量（>12%）的CP并未改善葡萄糖代谢指标，甚至下调了irs1的相对表达水平。
综上所述，推荐的饲料CP添加量为%至12%，因为这个范围内可以增强大口黑鲈的脂质和葡萄糖代谢，添加6%的CP对大口黑鲈的糖脂代谢最有益。© 2025化学工业协会
