文献类型： 外文期刊

作者： Wu, Xuehui ¹ ; Zhang, Xing ² ; Chen, Xuedong ¹ ; Ye, Aihong ¹ ; Cao, Jinru ¹ ; Hu, Xiaolong ³ ; Zhou, Wenlin ¹ ;

作者机构： 1.Zhejiang Acad Agr Sci, Inst Sericulture & Tea, Hangzhou 310021, Peoples R China

2.Suzhou Univ Sci & Technol, Sch Chem & Life Sci, Suzhou 215009, Peoples R China

3.Soochow Univ, Sch Biol & Basic Med Sci, Suzhou 215123, Peoples R China

关键词： Silkworm; Polylactic acid; Microbiota; Metabolite

期刊名称：ENVIRONMENTAL POLLUTION （ 影响因子：8.9； 五年影响因子：9.5 ）

ISSN： 0269-7491

年卷期： 2023 年 334 卷

页码：

收录情况： SCI

摘要： Polylactic acid (PLA) is a highly common biodegradable plastic and a potential threat to health and the environment. However, limited data are available on the effects of PLA exposure in the silkworm (Bombyx mori), a model organism used in toxicity studies. In this study, silkworms with or without PLA exposure (P1: 1 mg/L, P5: 5 mg/L, P25: 25 mg/L, and P0: 0 mg/L) for the entire 5th instar period were used to investigate the impact of PLA exposure on midgut morphology, larvae growth, and survival. Mitochondrial damage was observed in the P5 and P25 groups. The weights of the P25 posterior silk gland (5th day in the 5th instar), mature larvae and pupae were all significantly lower than those of the controls (P < 0.05). Dead worm cocoon rates and larva-pupa to 5th instar larvae ratios showed a positive and negative dose-dependent manner with respect to PLA concentrations, respectively. Additionally, reactive oxygen species levels and superoxide dismutase activity of the P25 midgut were significantly higher and lower when compared with controls, respectively (P < 0.05). The molecular mechanisms underlying the effects of PLA and associated physiological responses were also investigated. In the midgut metabolome, 127 significantly different metabolites (variable importance projection >1 and P < 0.05) were identified between the P0 and P25 groups and were mainly enriched for amino acid metabolism and energy supply pathways. The 16 S rDNA data showed that PLA altered microbial richness and structural composition. Microbiota, classified into 34 genera and 63 species, were significantly altered after 25 mg/L PLA exposure (P < 0.05). Spearman's correlation results showed that Bifidobacterium catenulatum and Schaalia odontolytica played potentially vital roles during exposure, as they demonstrated stronger correlations with the significantly different metabolites than other bacterial species. In sum, PLA induced toxic effects on silkworms, especially on energyand protein-relevant metabolism, but at high concentrations (25 mg/L). This prospective mechanistic investigation on the effects of PLA on larval toxicity provides novel insight regarding the ecological risks of biodegradable plastics in the environment.