摘要 In this study, polylactic acid (PLA), polybutylene glycol terephthalate (PBAT) in biodegradable plastics (BMPs) and polyethylene (PE) in conventional microplastics (CMPs) were selected as test chemicals, and Microcystis aeruginosa was used as the test organism. By testing indicators such as algal cell density, chlorophyll a (Chl-a), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), total intracellular soluble protein (TP) and reactive oxygen species (ROS), the effects of different dosages (50, 100, 150 and 200mg/L) and particle size (150, 250 and 500 μm) of PLA, PBAT and PE on the growth, oxidative stress and cell damage of Microcystis aeruginosa were investigated. The results showed that the growth and oxidative stress indexes of algal cells exhibited significant changes with exposure time under the single action of PLA/PBAT/PE. After 96h of exposure, compared with other treatment groups, the inhibition rate of PLA at a dosage of 100mg/L on Microcystis aeruginosa was the highest (16.31%), while the inhibition rate of PE at a particle size of 150 μm was the highest (15.97%). The exposure of PLA and PE significantly increased the contents of ROS, SOD, CAT and MDA in Microcystis aeruginosa, and their acute toxicity differences may be related to the roughness of the microplastic surfaces. PLA, as an aliphatic polyester, was more prone to hydrolysis in aquatic environments than PBAT, and the release potential of secondary microplastic fragments made it more severely acute toxic to algae.
Abstract：In this study, polylactic acid (PLA), polybutylene glycol terephthalate (PBAT) in biodegradable plastics (BMPs) and polyethylene (PE) in conventional microplastics (CMPs) were selected as test chemicals, and Microcystis aeruginosa was used as the test organism. By testing indicators such as algal cell density, chlorophyll a (Chl-a), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), total intracellular soluble protein (TP) and reactive oxygen species (ROS), the effects of different dosages (50, 100, 150 and 200mg/L) and particle size (150, 250 and 500 μm) of PLA, PBAT and PE on the growth, oxidative stress and cell damage of Microcystis aeruginosa were investigated. The results showed that the growth and oxidative stress indexes of algal cells exhibited significant changes with exposure time under the single action of PLA/PBAT/PE. After 96h of exposure, compared with other treatment groups, the inhibition rate of PLA at a dosage of 100mg/L on Microcystis aeruginosa was the highest (16.31%), while the inhibition rate of PE at a particle size of 150 μm was the highest (15.97%). The exposure of PLA and PE significantly increased the contents of ROS, SOD, CAT and MDA in Microcystis aeruginosa, and their acute toxicity differences may be related to the roughness of the microplastic surfaces. PLA, as an aliphatic polyester, was more prone to hydrolysis in aquatic environments than PBAT, and the release potential of secondary microplastic fragments made it more severely acute toxic to algae.
[1] 苗令占,邓肖雅,杨 铮,等.微塑料的老化过程、产物及其环境效应研究进展 [J]. 中国环境科学, 2023,43(11):6156-6171. Miao L Z, Deng X Y, Yang Z, et al. Progress in the aging process of microplastics, their products and their environmental effects [J]. China Environmental Science, 2023,43(11):6156-6171. [2] Besseling E, Wegner A, Foekema E M, et al. Effects of microplastic on fitness and PCB bioaccumulation by the Lugworm Arenicola marina (L.)[J]. Environmental Science & Technology, 2013,47(1):593-600. [3] Kaposi K L, Mos B, Kelaher B P, et al. Ingestion of microplastic has limited impact on a marine larva [J]. Environmental Science & Technology, 2014,48(3):1638-1645. [4] Carteny C C, Blust R. Not only diamonds are forever: Degradation of plastic films in a simulated marine environment [J]. Frontiers in Environmental Science, 2021,9:662844. [5] SHEN M C, SONG B, ZENG G M, et al. Are biodegradable plastics a promising solution to solve the global plastic pollution? [J]. Environmental Pollution, 2020,263:114469. [6] 张 敏,孟庆阳,刁晓倩,等.PLA/PBAT共混物的降解性能研究 [J]. 中国塑料, 2016,30(8):79-86. Zhang M, Meng Q Y, Diao X Q, et al. Study of degradation properties of PLA/PBAT blends [J]. China Plastics, 2016,30(8):79-86. [7] 孟庆阳,翁云宣.环氧类增容剂反应增容PLA/PBAT共混体系的研究 [J]. 中国塑料, 2014,28(2):91-95. Meng Q Y, Weng Y X. Study on the reactive capacitation of PLA/PBAT blended systems with epoxy-based capacitance enhancers [J]. China Plastics, 2014,28(2):91-95. [8] Napper I E, Thompson R C. Environmental deterioration of biodegradable, oxo-biodegradable, compostable, and conventional plastic carrier bags in the sea, soil, and open-air over a 3-year period [J]. Environmental Science & Technology, 2019,53:4775-4783. [9] Nazareth M, Marques M R, Leite M C, et al. Commercial plastics claiming biodegradable status: is this also accurate for marine environments [J]. Journal of Hazardous Materials, 2019,366:714-722. [10] Tabasi R Y, Ajji A. Selective degradation of biodegradable blends in simulated laboratory composting [J]. Polymer Degradation Stability, 2015,120:435-442. [11] Sintim H Y, Bary A I, Hayes D G, et al. Release of micro-and nanoparticles from biodegradable plastic during in situ composting [J]. Science of Total Environment, 2019,675:686-693. [12] Shi J, Wang Z, Peng Y M, et al. Effects of microplastics on soil carbon mineralization: The crucial role of oxygen dynamics and electron transfer [J]. Environmental Science & Technology, 2023,5736:13588-13600. [13] 郑涵月,孙姣霞,向 红,等.生物可降解塑料PBAT/PLA在典型非生物降解环境下的降解 [J]. 中国环境科学, 2023,43(8):4247-4254. Zheng H Y, Sun J X, Xiang H, et al. Degradation of biodegradable plastics PBAT/PLA in typical non-biodegradable environments [J]. China Environmental Science, 2023,43(8):4247-4254. [14] Manfra L, Marengo V, Libralato G, et al. Biodegradable polymers: a real opportunity to solve marine plastic pollution [J]? Journal of Hazardous Materials, 2021,416:125763. [15] Ganesan S, Ruendee T, Kimura S Y, et al. Effect of biofilm formation on different types of plastic shopping bags: structural and physicochemical properties [J]. Environmental Research, 2022,206: 112542. [16] Liu X M, Wang X L, Wang R J, et al. Effects comparison between the secondary nanoplastics released from biodegradable and conventional plastics on the transfer of antibiotic resistance genes between bacteria [J]. Environmental Pollution, 2023,317:120680. [17] Clx ement, L Hurel, C Marmier. Toxicity of TiO2 nanoparticles to cladocerans, algae, rotifers and plants -effects of size and crystalline structure [J]. Chemosphere, 2013,90(3):1083-1090. [18] Qi Y L, Beriot N, Gort G, et al. Impact of plastic mulch film debris on soil physicochemical and hydrological properties [J]. Environmental Pollution, 2020,266:115097. [19] Green D S, Boots B, Blockley D J, et al. Impacts of discarded plastic bags on marine assemblages and ecosystem functioning [J]. Environmental Science & Technology, 2015,49:5380-5389. [20] Green D S, Boots B, Sigwart J, et al. Effects of conventional and biodegradable microplastics on a marine ecosystem engineer (Arenicola marina) and sediment nutrient cycling [J]. Environmental Pollution, 2016,208:426-434. [21] Gonzalez P M, Tamayo B M, Pulido R G, Amariei, et al. Secondary nanoplastics released from a biodegradable microplastic severely impact freshwater environments [J]. Environmental Science Nano, 2019,6:1382-1392. [22] Su Y Y, Cheng Z R, Hou Y P, et al. Biodegradable and conventional microplastics posed similar toxicity to marine algae Chlorella vulgaris [J]. Aquatic Toxicology, 2022,244:106097. [23] A L Andrady. Microplastics in the marine environment [J]. Marine Pollution Bulletin, 2011,62(2011):1596-1605. [24] Ma, B, Xue W, Hu C, et al. Characteristics of microplastic removal via coagulation and ultrafiltration during drinking water treatment [J]. Chemical Engineering Journal, 2019,359:159-167. [25] Zheng X W, Liu X L, Zhang L L, et al. Toxicity mechanism of Nylon microplastics on Microcystis aeruginosa through three pathways: Photosynthesis, oxidative stress and energy metabolism [J]. Journal of Hazardous Materials, 2022,426:128094. [26] 雍玲丽,陈猷鹏,郭劲松,等.纳米银对铜绿微囊藻生物毒性的电荷效应 [J]. 中国环境科学, 2024,44(1):510-519. Yong L L, Chen Y P, Guo J S, et al. Charge effect of nanosilver on the biotoxicity of Microcystis aeruginosa [J]. China Environmental Science, 2024,44(1):510-519. [27] Zhang C, Chen X, Wang J, et al. Toxic effects of microplastic on marine microalgae Skeletonema costatum: Interactions between microplastic and algae [J]. Environmental Pollution, 2017,220(PtB): 1282-1288. [28] Zheng X W, Zhang W Z, Yuan Y, et al. Growth inhibition, toxin production and oxidative stress caused by three microplastics in Microcystis aeruginosa [J]. Ecotoxicology and Environmental Safety, 2021,208:111575. [29] Canniff P M, Hoang T C. Microplastic ingestion by Daphnia magna and its enhancement on algal growth [J]. Science of Total Environment, 2018,633:500-507. [30] Mao Y F, Ai H N, Chen Y, et al. Phytoplankton response to polystyrene microplastics: perspective from an entire growth period [J]. Chemosphere, 2018,208:59-68. [31] Ye T R, Yang A, Wang Y L, et al. Changes of the physicochemical properties of extracellular polymeric substances (EPS) from Microcystis aeruginosa in response to microplastics [J]. Environmental Pollution, 2022,315:120354. [32] Cui L, Fan L, Li Z, et al. Characterization of extracellular polymeric substances from Synechocystis sp. PCC6803 under Cd (II), Pb (II) and Cr (VI) stress [J]. Journal of Environmental Chemical Engineering, 2021,9(4):105347. [33] Zheng S, Zhou Q, Chen C, et al. Role of extracellular polymeric substances on the behavior and toxicity of silver nanoparticles and ions to green algae Chlorella vulgaris [J]. Science of the Total Environment, 2019,660:1182-1190. [34] C.Amaneesh, Shankari Anna Balan, P.S.Silpa, et al. Gross Negligence: Impacts of Microplastics and Plastic Leachates on Phytoplankton Community and Ecosystem Dynamics [J]. Environmental Science & Technology, 2023,57:5-24. [35] Angel B M, Vallotton P, Apte S C, et al. On the mechanism of nanoparticulate CeO2 toxicity to freshwater algae [J]. Aquatic Toxicology, 2015,(168):90-97. [36] Feng L J, Li J W, Xu E G, et al. Short-term exposure to positively charged polystyrene nanoparticles causes oxidative stress and membrane destruction in cyanobacteria [J]. Environmental Science: Nano, 2019,6(10):3072-3079. [37] Scialo F, Sriram A, Fernandez-Ayala D, et al. Mitochondrial ROS produced via reverse electron transport extend animal lifespan [J]. Cell Metabolism, 2019,23:725-734. [38] Yang W F, Gao X X, Wu Y X, et al．The combined toxicity influence of microplastics and nonylphenol on microalgae Chlorella pyrenoidosa [J]. Ecotoxicology and Environmental Safety, 2020,195: 110484. [39] Pirinccioglu A G, Gökalp D, Pirinccioglu M, et al. Malondialdehyde (MDA) and protein carbonyl (PCO) levels as biomarkers of oxidative stress in subjects with familial hypercholesterolemia [J]. Clinical Biochemistry, 2010,43(15):1220-1224. [40] Liu J, Zhang T, Tian L L, et al. Aging significantly affects mobility and contaminant⁃mobilizing ability of nanoplas tics in saturated loamy sand [J]. Environmental Science & Technology, 2019,53(10):5805-5815. [41] Mahana A, Guliy O I, Mehta S K. Accumulation and cel⁃ lular toxicity of engineered metallic nanoparticle in fresh⁃ water microalgae: Current status and future challenges [J]. Ecotoxicology and Environmental Safety, 2021,208:111662. [42] Attia H, Karray N, Msilini N, et al. Effect of salt stress on gene expression of superoxide dismutases and copper chaperone in Arabidopsis thaliana [J]. Biologia Plantarum, 2011,55(1):159-163. [43] Scandalios J G. Oxidative stress: Molecular perception and transduction of signals triggering antioxidant gene defenses [J]. Brazilian Journal of Medical and Biological research, 2005,38(7): 995-1014. [44] Liu Y, Wang Q, Zhang Y, et al. Synergistic and antagonistic effects of salinity and pH on germination in Switchgrass (Panicum virgatum L) [J]. Public Library of Science One, 2014,9(1):85282. [45] 许 楹,殷超凡,岳纹龙,等.石油基塑料的微生物降解 [J]. 生物工程学报, 2019,35(11):2092-2103. Xu Y, Yin C F, Yue W L, et al. Microbial degradation of petroleum-based plastics [J]. Chinese Journal of Biotechnology, 2019,35(11): 2092-2103. [46] Fu D, Zhang Q, Fan Z, et al. Aged microplastics polyvinyl chloride interact with copper and cause oxidative stress towards microalgae Chlorella Vulgaris [J]. Aquatic Toxicology, 2019,216:105319. [47] 贺 艳,王 晶,赵 曼,等.可降解微塑料对磺胺嘧啶的吸附行为研究 [J/OL]. 环境科学与技术, 2024:1-15. He Y, Wang J, Zhao M, et al. Adsorption behaviour of degradable microplastics on sulfadiazine [J/OL]. Environmental Science and Technology, 2024,1-15. [48] 金 琰,蔡凡凡,王立功,等.生物可降解塑料在不同环境条件下的降解研究进展 [J]. 生物工程学报, 2022,38(5):1784-1808. Jin Y, Cai F F, Wang L G, et al. Progress in the degradation of biodegradable plastics under different environmental conditions [J]. Journal of Bioengineering, 2022,38(5):1784-1808. [49] 肖 娜,王艳华,刘锐涵,等.可生物降解聚乳酸塑料产生二次微塑料的行为特征 [J]. 环境化学, 2024,44(1):1-13. Xiao N, Wang Y H, Liu R H, et al. The behavior characteristics of secondary microplastics from biodegradable polylactic acid [J]. Environmental Chemistry, 2024,44(1):1-13.
