Titanium dioxide (TiO₂) is used in numerous applications, such as medicinal products, cosmetics and food whitening (E171). This work aimed to assess the protective role of Lactobacillus plantarum in the TiO₂ nanoparticles induced toxicity in Oreochromis niloticus. A total number of 600 O. niloticus was divided into four groups G1–4; G1 was fed on the basal diet, G2 fed on L. plantarum, G3 fed on contaminated TiO₂ NPs-diet (1 mg/kg body weight), while G4 fed on contaminated TiO₂ NPs-diet then treated with L. plantarum for the same period. Fish immunity was evaluated at 10, 20 and 30 days except G4 were at 20, 40 and 60 days. The gene expression of the interleukin (IL)-1β, IL-6, IL-10 and tumour necrosis factor-α were significantly enhanced in G4 compared with G3. On days 10 and 20, the phagocytic activity was significantly increased in G4 compared with G1 and G3, while it was decreased on day 30 in G4 and G3. In addition, oxidative burst activity and serum antibacterial activity had the same trend indicating the immunosuppression effects of TiO₂ NPs. The mortality rate of fish challenged against Aeromonas hydrophila was decreased in G4 (30%, 50% and 60%) compared with G3 (50%, 50% and 70%) respectively. The antioxidant enzymes catalase, glutathione peroxidase and superoxide dismutase were stimulated, indicating the generation of reactive oxygen species by TiO₂ in exposed O. niloticus. It was concluded that L. plantarum could protect O. niloticus against TiO₂ NPs-induced immunosuppression by enhancing their immune response and oxidative status.

中文翻译：

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植物乳杆菌改善二氧化钛纳米粒子（金红石）对尼罗罗非鱼的免疫学影响

二氧化钛 (TiO ₂ ) 用于多种应用，例如医药产品、化妆品和食品增白 (E171)。本工作旨在评估植物乳杆菌在 TiO _{2纳米颗粒诱导的}尼罗罗非鱼毒性中的保护作用。一共600个O。尼罗罗非鱼分为四组G1-4；G1 以基础日粮喂养，G2 以L喂养。植物，G3 以受污染的 TiO ₂  NPs-饮食（1 mg/kg 体重）为食，而 G4 以受污染的 TiO ₂  NPs-饮食为食，然后用L处理。植物同一时期。除了 G4 在 20、40 和 60 天外，鱼类免疫力在 10、20 和 30 天进行评估。与 G3 相比，G4 中白细胞介素 (IL)-1β、IL-6、IL-10 和肿瘤坏死因子-α 的基因表达显着增强。第10天和第20天，G4的吞噬活性较G1和G3明显增加，而G4和G3的吞噬活性在第30天下降。此外，氧化爆发活性和血清抗菌活性具有相同的趋势，表明TiO ₂  NPs的免疫抑制作用。受嗜水气单胞菌攻击的鱼的死亡率与 G3（50%、50% 和 70%）相比，G4（30%、50% 和 60%）分别下降。_{抗氧化酶过氧化氢酶、谷胱甘肽过氧化物酶和超氧化物歧化酶受到刺激，表明TiO 2}在暴露的O中产生活性氧。尼罗罗非鱼 得出的结论是L . 植物可以保护O。尼罗罗非鱼 通过增强其免疫反应和氧化状态来对抗 TiO _{2 NPs 诱导的免疫抑制。}