Hydrogen−rich water (HRW) is widely recognized for its growth promoting, antioxidant, and anti−inflammatory properties. However, little is known about the role of HRW in aquaculture. This study aims to investigate how different concentrations of HRW affect the growth performance, digestive ability, antioxidant capacity, mTOR signaling pathway, and gut microbiota of juvenile largemouth bass. We randomly assigned 360 fish (13.73 ± 0.1 g) to three treatments. The control group was maintained in regular water, while the treatment groups were treated with different concentrations of H2 dissolved in water, which were H1 (179.65 ± 31.95 ppb) and H2 (280.65 ± 64.43 ppb), respectively. Through an analysis of the three treatments, it was found that H1 significantly increased the final body weight, weight gain rate, specific growth rate, and survival rate, and reduced the feed conversion ratio (p < 0.05). In addition, the trypsin activity was significantly increased in the intestine (p < 0.05), and the expression of genes related to the glucose metabolism (pk and pepck) and mTOR (tor, akt, s6k1, 4ebp1, and ampka) signaling pathways were significantly increased in the liver in H1 (p < 0.05). The relative abundance of Blautia in the gut microbiota (p < 0.05) was significantly increased in H1. Therefore, these results indicated that H1 can significantly improve growth performance, promote intestinal digestion, activate the glucose metabolism pathway and mTOR signaling pathway, and increase the abundance of beneficial bacteria in the gut of largemouth bass. These findings provided valuable support for the application of HRW to support the healthy aquaculture of largemouth bass.

中文翻译：

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不同浓度富氢水对大口黑鲈生长性能、消化能力、抗氧化能力、葡萄糖代谢途径、mTOR信号通路和肠道菌群的影响


富氢水 (HRW) 因其促进生长、抗氧化和抗炎特性而被广泛认可。然而，人们对硬红水在水产养殖中的作用知之甚少。本研究旨在探讨不同浓度的HRW如何影响幼年大口黑鲈的生长性能、消化能力、抗氧化能力、mTOR信号通路和肠道微生物群。我们将 360 条鱼 (13.73 ± 0.1 g) 随机分配到三个处理组。对照组维持常规水，而处理组则用不同浓度的溶解在水中的H2处理，分别为H1（179.65±31.95ppb）和H2（280.65±64.43ppb）。通过对3个处理的分析发现，H1显着提高了最终体重、增重率、特定生长率和成活率，并降低了饲料转化率（p < 0.05）。此外，肠道中胰蛋白酶活性显着增加（p < 0.05），与葡萄糖代谢（pk 和 pepck）和 mTOR（tor、akt、s6k1、4ebp1 和 ampka）信号通路相关的基因表达量也显着升高。 H1 肝脏中显着增加 (p < 0.05)。 H1 中肠道微生物群中 Blautia 的相对丰度 (p < 0.05) 显着增加。因此，这些结果表明H1可以显着提高大口黑鲈的生长性能，促进肠道消化，激活葡萄糖代谢途径和mTOR信号通路，增加大口黑鲈肠道内有益细菌的丰度。这些发现为应用硬红水支持大口黑鲈的健康养殖提供了宝贵的支持。