Freshwater Fisheries Research Institute of Jiangsu Province, 79 Chating East Street, Nanjing 210017, China; Biology Program, School of Distance Education, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia.
Institute of Marine Biology, College of Oceanography, Hohai University, Nanjing 210098, China.
Sci Total Environ. 2022 Aug 10;833:155722. doi: 10.1016/j.scitotenv.2022.155722. Epub 2022 May 4.
The widespread generation and accumulation of plastic waste has become a globally recognized problem. However, there are limited reports on the adverse effects of nanomaterials on freshwater crustaceans. This study tested the acute effects of different concentrations (0, 5, 10, and 20 mg/L) after 48 h exposure of 75 nm polystyrene nanoplastic on intestinal microbes, and oxidative stress parameters of freshwater crayfish, Procambarus clarkii. High-throughput sequencing analysis revealed the richness, diversity, and composition of intestinal microbiota in P. clarkii exposed to polystyrene nanoplastic. At the genus level, abundances of Lactobacillus, Faecalibaculum, Niveibacterium, and Candidatus Bacilloplasma were significantly different. The reduced abundance of Lactobacillus could affect the balance of intestinal microbes through quantitative disadvantage, which may lead to reduced immunity of P. clarkii. Streptococcus salivarius, Clostridium butyricum and Lachnospiraceae bacterium10-1 in intestinal tract reached maximum abundance at a polystyrene concentration of 20 mg/L. The increase in the number of some pathogenic bacteria may upset the balance of intestinal microorganisms through the number of dominance, and the decrease in the relative abundance of lactic acid bacteria. Probiotics, such as Lactobacillus salivarius, Lactobacillus murinus, Lactobacillus gasseri, Lactobacillus reuteri, Lactobacillus iners AB-1, and Lactobacillus crispatus in the intestinal tract reached the lowest value at a concentration of 10 mg/L. The reduced abundance of Lactobacillus can affect the balance of intestinal microbes through quantitative disadvantage, which may lead to reduced immunity in P. clarkii. At nanoplastic 10 mg/L, the relative abundance of intestinal pathogens increased, while the relative abundance of lactic acid bacteria and other probiotics decreased. With increases in nanoplastic concentrations, the values of glutathione (GSH), superoxide dismutase (SOD), acid phosphatase (ACP), lysozyme (LZM), alkaline phosphatase (AKP), peroxidase (POD), glutathione peroxidase (GPX), and protein carbonylation were significantly changed. Our data suggested that Lactobacillus may play an adjunctive role in the treatment of oxidative stress in P. clarkii exposed to 75 nm polystyrene. This study represents an important step towards a better understanding of the toxic effects of nanoplastics on aquatic crustaceans.
广泛产生和积累的塑料废物已成为全球公认的问题。然而，关于纳米材料对淡水甲壳类动物的不良影响的报道有限。本研究测试了在 48 h 暴露于 75nm 聚苯乙烯纳米塑料后，不同浓度（0、5、10 和 20 mg/L）对淡水小龙虾（Procambarus clarkii）肠道微生物和氧化应激参数的急性影响。高通量测序分析揭示了暴露于聚苯乙烯纳米塑料的 P. clarkii 肠道微生物的丰富度、多样性和组成。在属水平上，Lactobacillus、Faecalibaculum、Niveibacterium 和 Candidatus Bacilloplasma 的丰度有显著差异。Lactobacillus 的丰度减少可能通过定量劣势影响肠道微生物的平衡，从而降低 P. clarkii 的免疫力。肠道中链球菌（Streptococcus salivarius）、丁酸梭菌（Clostridium butyricum）和 Lachnospiraceae bacterium10-1 的丰度在聚苯乙烯浓度为 20 mg/L 时达到最大值。一些致病菌数量的增加可能会通过数量优势扰乱肠道微生物的平衡，同时降低乳酸菌的相对丰度。肠道中乳杆菌属（Lactobacillus）的某些益生菌，如唾液乳杆菌（Lactobacillus salivarius）、鼠李糖乳杆菌（Lactobacillus murinus）、格氏乳杆菌（Lactobacillus gasseri）、雷氏乳杆菌（Lactobacillus reuteri）、AB-1 短乳杆菌（Lactobacillus iners AB-1）和卷曲乳杆菌（Lactobacillus crispatus）的丰度在浓度为 10 mg/L 时达到最低值。Lactobacillus 的丰度减少可能会通过定量劣势影响肠道微生物的平衡，从而降低 P. clarkii 的免疫力。在纳米塑料 10 mg/L 时，肠道病原体的相对丰度增加，而乳酸菌和其他益生菌的相对丰度下降。随着纳米塑料浓度的增加，谷胱甘肽（GSH）、超氧化物歧化酶（SOD）、酸性磷酸酶（ACP）、溶菌酶（LZM）、碱性磷酸酶（AKP）、过氧化物酶（POD）、谷胱甘肽过氧化物酶（GPX）和蛋白质羰基化的含量值发生显著变化。我们的数据表明，Lactobacillus 可能在治疗暴露于 75nm 聚苯乙烯的 P. clarkii 的氧化应激中发挥辅助作用。本研究是朝着更好地了解纳米塑料对水生甲壳类动物的毒性作用迈出的重要一步。
