MOLECULES
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2023
·Vol. 28
·期 12
·4774
·
IF 4.6
Qingqing Xiang,Ying Zhou,Chengxia Tan
Prothioconazole (PTC) is a broad-spectrum triazole fungicide with one asymmetric center and consists of two enantiomers,R-(−)-PTC andS-(+)-PTC. To address the concern of its environmental safety, the enantioselective toxic effects of PTC onScendesmus obliquus(S. obliquus) were investigated. PTC racemates (Rac-PTC) and enantiomers exhibited dose-dependent acute toxicity effects againstS. obliquusat a concentration from 1 to 10 mg·L−1. The 72 h-EC50 value ofRac-,R-(−)-, andS-(+)-PTC is 8.15, 16.53, and 7.85 mg·L−1, respectively. The growth ratios and photosynthetic pigment contents of theR-(−)-PTC treatment groups were higher than theRac- andS-(+)-PTC treatment groups. Both catalase (CAT) activities and esterase activities were inhibited in theRac- andS-(+)-PTC treatment groups at high concentrations of 5 and 10 mg·L−1, and the levels of malondialdehyde (MDA) were elevated, which exceeded the levels in algal cells for theR-(−)-PTC treatment groups. PTC could disrupt the cell morphology ofS. obliquusand induce cell membrane damage, following the order ofS-(+)-PTC ≈Rac-PTC >R-(−)-PTC. The enantioselective toxic effects of PTC onS. obliquusprovide essential information for its ecological risk assessment.Keywords:prothioconazole;toxicity effects;Scenedesmus obliquus;enantioselectivity
研究领域:
环境科学
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毒理学
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生态学
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PubMed
高影响因子
CHIRALITY
·
2016
·Vol. 29
·期 2
·61-69
·
IF 2.025
Peng Xu,Ledan Huang
In this study the stereoselective bioaccumulation and transformation of triadimefon and the toxicity of triadimefon and its metabolite triadimenol to the green algae Scenedesmus obliquus were studied. In growth inhibition experiments, triadimenol was more toxic than triadimefon, and (1S,2R)-triadimenol, which has the largest fungicidal activity, presented the highest toxicity to the algae. In bioaccumulation experiments, triadimefon was rapidly taken up by algae cells, and the decrease in the concentration of triadimefon was accompanied by an increase in triadimenol. The transformation of S-(+)- triadimefon was faster than that of the R-(−)-enantiomer, resulting in four triadimenol stereoisomers at different forming rates: B2 (1S, 2S) > B1 (1R, 2R) > A2 (1S, 2R) > A1 (1R, 2S). Thus, it is necessary to explore the enantioselective toxicology and ecological fate of these chiral pesticides in an environmental risk assessment. Also, their metabolites should be paid specific attention to since they may pose higher ecological risks.
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高影响因子
AQUATIC TOXICOLOGY
·
2025
·
IF 4.3
Wei Hong,Fan Zhang,Zhuang Wang
Graphdiyne (GDY), an emerging 2D carbon nanomaterial, holds promise yet remains unexplored for environmental hazards. Herein, we investigated the toxicity effects and mechanisms of GDY towards the freshwater microalga Scenedesmus obliquus at environmentally relevant concentrations. The results revealed that 1 mg/L of GDY inhibited the growth of the algae and significantly induced a decrease in photosynthetic pigments. Exposure to 0.1 and 1 mg/L of GDY led to a reduction in cell membrane permeability and induced intracellular oxidative stress in the algae. Further, 1 mg/L of GDY caused oxidative damage to the algal cells. Molecular modeling indicated that GDY could directly affect the stability of dsDNA fragment. Transcriptome analysis showed that GDY at 1 mg/L influenced the expression of 2216 genes, with the glycerolipid metabolism pathway being enriched significantly. Metabolome analysis identified 129 differentially expressed metabolites (DEMs) in the algae exposed to 1 mg/L of GDY, revealing three significantly disrupted pathways: glycerophospholipid metabolism, pentose phosphate pathway, and flavonoid biosynthesis. The integrated transcriptome and metabolome analysis suggested that GDY exposure downregulated the level of a lysophosphatidylcholine species (LPC 18:3) by inhibiting the expression of genes related to FMN binding molecular functions. Simultaneously, the algae responded to GDY exposure by upregulating genes involved in the biological process of carbohydrate metabolic process and the molecular function of hydrolase activity, as well as increasing the levels of DEMs, specifically a lysophosphatidic acid species (LPA 16:4). This study elucidates the stress mechanisms induced by GDY in aquatic organisms and emphasizes the importance of monitoring its acute biological effects.
研究领域:
环境科学
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分子生物学
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PubMed
高影响因子
AQUATIC TOXICOLOGY
·
2025
·
IF 4.3
Tianlie Luo,Jingjing Shi,Ping Zhang,Shuang Yang,Guo Liu,Willie J.G.M. Peijnenburg
In this study, Scenedesmus obliquus ( S. obliquus ) has been employed as a model organism to investigate the bioaccumulation, metabolism, and toxicity mechanisms of tricresyl phosphate (TCP). The results indicated that S. obliquus enhanced TCP degradation in water by 97% after 14 days. The bioaccumulation factor of tricresyl phosphate in S. obliquus were calculated to be 8. When exposed to a high concentration of TCP (160 μmol/L), the algal growth rate was initially negative at 24 h, but gradually recovered over time. By 96 h, the inhibition rate was 64.74% and the EC 50 values was determined to be 86.41 μmol/L. Prolonged exposure to TCP substantially inhibited photosynthesis in S. obliquus , as indicated by a significant reduction in chlorophyll content. The addition of humic acid (HA), a representative substance of dissolved organic matter, exacerbated TCP toxicity by increasing ROS production, indicating a synergistic effect between HA and TCP. Conversely, a mixed nitrogen source reduced TCP toxicity. Four TCP metabolites were identified, resulting from hydroxylation, ketonization, hydrolysis, and ester bond cleavage. ECOSAR analysis revealed that these metabolites exhibit lower toxicity compared to TCP. These findings indicate that metabolic transformations within the algae may mitigate TCP toxicity, whereas HA significantly exacerbates TCP-induced oxidative stress. This study offers novel insights into the ecological risks of TCP in aquatic environments, especially in the presence of natural organic matter.
研究领域:
环境科学
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毒理学
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PubMed
高影响因子
RENEWABLE ENERGY
·
2018
·
IF 4.9
Yi Zhang,Xiaoying Kong,Zhongming Wang,Yongming Sun,Shunni Zhu,Lianhua Li,Pengmei Lv
Cell wall disruption is an essential downstream processing step for improving the efficiency of lipid extraction from microalgae. Enzyme-assisted extraction of lipid from microalga Scenedesmus sp. with cellulase , xylanase and pectinase, using various parameters, such as enzyme concentration , temperature, pH and incubation time, was optimized by central composite design (CCD) coupled with response surface methodology (RSM). Both the lipid extraction from microalgae and the fatty acid methyl esters (FAMEs) production under optimal conditions showed a ∼twofold in the yields compared to the control group with no enzymatic treatment . SEM images, FTIR measurement, XPS and HPLC analysis showed that the enzymatic pretreatment caused significant alterations in the cell wall structure of microalgae. And the disruption of microalgal cell walls was primarily attributed to the breakage of β-glucosidic linkages in cellulose and hemicellulose . The study showed a promising approach can lead to an improvement in the lipid extraction yield from microalgae and further provide valuable information for the use of enzymes in microalgal processes.
研究领域:
生物技术
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可再生能源
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微生物学
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DOI
高影响因子
Plants-Basel
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2020
·Vol. 9
·期 12
·1748
·
IF 2.762
Zhou Li,Philippe Juneau,Yingli Lian,Wei Zhang,Shanquan Wang,Cheng Wang,Longfei Shu,Qingyun Yan,Zhili He,Kui Xu
The effects of the photocatalytic toxicity of titanium dioxide nanoparticle (nano-TiO2) on phytoplankton are well understood. However, as UV light intensity decreases sharply with the depth of the water column, the effects of nano-TiO2itself on deeper water phytoplankton, such as green algae, need further research. In this research, we investigated the effects of three sizes of TiO2(10, 50 and 200 nm) on the photosynthetic and antioxidative processes ofScenedesmus obliquusin the absence of UV light. We found that 50 nm and 10 nm TiO2(10 mg/L) inhibited growth rates and the maximal photosystem II quantum yield compared to the control inScenedesmus obliquus. The minimal and maximal fluorescence yields, and the contents of reactive oxygen species and lipid peroxidation, increased, indicating that photosynthetic energy/electrons transferred to oxygen and induced oxidative stress in nano-TiO2-treated samples. In addition, we found that aggregations of algae and 10 nm TiO2were present, which could induce cell membrane disruption, and vacuoles were induced to cope with nano-TiO2stress inScenedesmus obliquus. These results enhance our understanding of the effects of nano-TiO2on the photosynthetic and antioxidative processes of green algae, and provide basic information for evaluating the ecotoxicity of nano-TiO2in freshwater ecosystems.Keywords:titanium dioxide nanoparticle;photosynthesis;oxidative stress;Scenedesmus obliquus
研究领域:
环境科学
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水生生态学
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植物生理学
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DOI
PubMed
高影响因子
JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART A-TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING
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2017
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IF 1.425
Nan Ye,Zhuang Wang,Hao Fang,Se Wang,Fan Zhang
A combined ecotoxicity study was carried out with nano-zinc oxide (nZnO) and nano-copper oxide (nCuO) to freshwater algae Scenedesmus obliquus. Concentration–response analysis indicated that the dissolved metal fraction was not the major source of individual and combined toxicity of the metal-oxide nanoparticles (MONPs). Moreover, the contribution of the nCuO (based on metallic mass) to the combined toxicity was greater than that of the nZnO. The observed combined toxicity can be predicted by the pharmacological concepts of concentration addition (CA) and independent action (IA). Combined toxicity prediction (in terms of median effect concentration) based on both concepts tends to overestimate the overall observed toxicity of the MONP mixtures. CA was more accurate for predicting the combined toxicity than IA. It may be concluded that CA gives a valid estimation of the overall ecotoxicity for mixtures comprising of similar acting MONPs.
研究领域:
环境科学
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毒理学
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DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2020
·Vol. 27
·期 16
·20545-20553
·
IF 3.056
Xu Wenjing,Tan Liju,Zhao Ting,Zhu Xiaolin,Wang Jiangtao
The expanding production and widespread application of acrylamide caused inevitable release to aquatic ecosystems. Contrary to its extensive attention to human and animal health, the hazards of acrylamide to the aquatic primary productivity have been rarely studied. The potential effects of acrylamide on the marine algae ( Nitzschia closterium ) and the limnetic algae ( Scenedesmus quadricauda ) were investigated by monitoring cell abundance, total chlorophyll content, maximum photosystem II (PSII) quantum yield (Fv/Fm), and reactive oxygen species (ROS). The growth of two algae was significantly inhibited by acrylamide. The 96 h EC 50 of acrylamide on N. closterium and S. quadricauda were 5.50 mg L −1 and 45.3 mg L −1 , and no observed effect concentration (NOEC) were 1.07 mg L −1 and 6.97 mg L −1 , respectively. After 96 h exposure to 50 mg L −1 of acrylamide, the total chlorophyll content declined to approximate 18% ( N. closterium) and 48% ( S. quadricauda ), and Fv/Fm was observed to be 0.35 and 0.32 for N. closterium and S. quadricauda , respectively. ROS was significantly increased following higher exposure concentrations, and its levels increased around 2.1-fold and 1.4-fold following exposure to 5 mg L −1 of acrylamide. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed the visible cell plasmolysis, rupture of the plasma membrane, cell vacuolization, and disintegration of chloroplasts of the algae caused acrylamide.
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高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2020
·Vol. 27
·期 22
·28198-28208
·
IF 3.056
Chen Qiaohong,Zhang Li,Han Yihong,Fang Jingyun,Wang Haiying
The degradation and metabolic pathways of sulfamethazine (SMZ) and enrofloxacin (ENR) via microalgal treatment systems were investigated in this study. SMZ and ENR applied at 1–25 mg L −1 did not significantly inhibit the growth of Chlorella vulgaris or Scenedesmus obliquus . SMZ and ENR exposure did not significantly alter the maximum quantum efficiencies of C. vulgaris and S. obliquus . When cultured at light intensities of 45–50 μmol photon m −2 s −1 , the C. vulgaris and S. obliquus treatment systems achieved 24% and 11% degradation, respectively. The greatest removal of ENR was 52% and 43.3%, for C. vulgaris and S. obliquus treatment systems , respectively, after 15 days. The results indicated that the degradation of SMZ and ENR occurred by a combination of biodegradation and photolysis. Kinetic investigations revealed that the removal of SMZ and ENR (5 mg L −1 ) followed a first-order model, with apparent rate constants ( k ) ranging from 0.0141 to 0.0048 day −1 and 0.0132 to 0.0086 day −1 , respectively. Fifteen metabolites of SMZ and five intermediates of ENR were identified by UPLC-MS, and degradation pathways for SMZ and ENR were proposed. SMZ transformation reactions included ring cleavage, hydroxylation, methylation, and oxidation, whereas ENR was degraded by dealkylation, decarboxylation, and defluorination.
Graphical abstract
研究领域:
环境科学
·
微生物学
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DOI
PubMed
高影响因子
HARMFUL ALGAE
·
2018
·
IF 4.138
Miaomiao Zhao,Xinyi Chen,Ning Ma,Qiuyue Zhang,Dong Qu,Ming Li
To form Microcystis blooms, Microcystis must be competitively dominant to other phytoplankton species to produce enough biomass. The aim of this study was to determine the competition mechanisms between Microcystis aeruginosa and Scenedesmus obliquus . M. aeruginosa and S. obliquus were separately cultured in the filtrate of mono and mixed cultures of M. aeruginosa and S. obliquus with varying treatments concerning N, P and iron availability. The inhibition rate for M. aeruginosa was 20–31% when cultured in mono and mixed culture filtrates enriched with N and P, but this rate was reduced to −15 to 19% when cultured in filtrates enriched with N, P and iron. The inhibition rate for M. aeruginosa decreased from 80 to 100% to 11–39% in dialytic filtrates. However, there were no differences in inhibition rate for S. obliquus, regardless of filtrate or dialytic filtrate treatments. The potential allelochemical, 2-butyl-octanol (0.144 mg L −1 ), was found to have little inhibitory effect to M. aeruginosa or S. obliquus . Thus, previously reported allelopathy to Microcystis would be overestimated. We also report a new mechanism in phytoplankton competition in this study. The phytoplankton secreted humic acid-like substances that can reduce the bioavailability of iron, resulting in the inhibition of other phytoplankton.
研究领域:
生态学
·
环境科学
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DOI
PubMed
高影响因子
Journal of Cleaner Production
·
2026
·
IF 10.7
An'an Xiao,Lu Xiong,Shanshan Shen,Xinran Li,Shulei Yang,Fangyan Shen,Qian Hu,Fangni Lin,Lian Huang,Jinquan Liu,Zhaohui Zhang,Hui Wang
Physiological & transcriptomic responses of Scenedesmus obliquus to 0.01–20.0 mg/L BeSO 4 were studied. • S. obliquus accumulated 3.53 mg of BeSO 4 with 88.1% removal efficiency at 20.0 mg/L. • Genes related to photosynthesis (44), stress response (93), and nitrogen metabolism (46) were upregulated. • Eighty-six upregulated ion-binding and transport genes promoted Be 2+ bioaccumulation. • S.obliquus shows promise for bioremediation of beryllium-contaminated aquatic environments. Beryllium (Be) is a widely utilized industrial metal with favorable physicochemical properties but poses severe chronic toxicity to aquatic organisms and humans, mandating safe and efficient removal from aqueous solutions. Current algal biosorption research remains limited for Be 2+ separation and underlying molecular mechanisms. In this study, the green microalgae Scenedesmus obliquus was exposed to varying concentrations of BeSO 4 (0.01, 0.1, 1.0, 10.0, and 20.0 mg/L), and its growth, photosynthesis, oxidative stress response, Be 2+ removal performance, and transcriptomic responses were investigated. Short-term exposure to BeSO 4 had negligible effects on microalgal cell growth, chlorophyll a content and antioxidant system, whereas high dose (20.0 mg/L) or prolonged exposure (4 days) significantly inhibited these processes. The total bioaccumulation amount of beryllium increased continuously with elevating BeSO 4 concentrations, ranging from 0.002 mg to 3.53 mg. Although the beryllium removal efficiency was relatively lower under 1 mg/L BeSO 4 treatment (40.02%), it exhibited a steady increase with rising BeSO 4 concentration and ultimately reached 88.14% at 20.0 mg/L BeSO 4 on day 1. Transcriptomic analysis revealed that most genes associated with photosynthesis (44 transcripts), antioxidant system (33), stress response (60), nitrogen metabolism (46), endocytosis (38), and ion binding and transport (86) were upregulated, contributing to the high tolerance and total bioaccumulation of S. obliquus to beryllium ions. These findings revealed physiological and molecular mechanisms of beryllium tolerance and bioaccumulation in S. obliquus , providing a scientific foundation for the treatment of beryllium-containing wastewater and aquatic bioremediation. Download: Download high-res image (300KB) Download: Download full-size image
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高影响因子
COMPUTERS AND ELECTRONICS IN AGRICULTURE
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2021
·
IF 5.565
Bingquan Chu,Kai Chen,Xiaoxiao Pan,Qianying Wu,Shiwang Liu,Jinyan Gong,Xiaoli Li
Microalgae lipid and its degree of fatty acid unsaturation (DU) have the ability to undergo programmatic changes in response to different environmental and culture conditions. A real-time and reliable approach to monitor the change patterns of lipid-accumulation and DU is crucial for microalgal culture and bioprocess control. In this study, a fast visual and nondestructive method based on visible/short-wave near-infrared hyperspectral imaging (V/SNIR HSI) at 400–1000 nm region was developed to investigate the dynamic changes and content distribution of lipids and DU of Scenedesmus obliquus treated by nitrogen-low stress (0.3 g/L NaNO 3 , NL) and nitrogen-free stress (0 g/L NaNO 3 , NF). After collecting the average spectra from the region of interests (ROIs), the competitive adaptive reweighted sampling (CARS) algorithm and the successive projection algorithm (SPA) were applied to pick effective wavebands from the spectral data for the establishment of the lipid concentration and DU estimation models including partial least squares regression (PLSR) and multiple linear regression (MLR) . The prediction results show the CARS-PLSR (R p = 0.9762, RMSE p = 0.0143) and CARS-MLR (R p = 0.9477, RMSE p = 0.5718) performed the best for lipids and DU of S. obliquus , respectively. Based on the optimal models, the spatial distribution of lipid abundance and DU in liquid suspension were visualized, which could be helpful in exploring the dynamic process of lipid synthesis and DU of S. obliquus. The overall results show that V/SNIR HSI is a promising technique for fast and noninvasively monitoring the lipid-accumulation and its characteristics i.e. DU in situ, and is expected to be applied for efficient and high-quality lipid production in microalgae industries.
研究领域:
生物技术
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环境科学
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光谱学
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微生物学
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高影响因子
危险品化学品经营许可证（带存储）