ENVIRONMENT INTERNATIONAL
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2024
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IF 10.3
Tianao Mao,Wenbin Liu,Jinglin Deng,Chunci Chen,Tianqi Jia,Haifeng Li,Fei Yin
N , N ′-Substituted p -phenylenediamines (PPDs) are widely used as antioxidants in the rubber industry and are released into the environment in large quantities during the production and use of rubber products. We quantified PPDs and PPD quinone derivatives (PPD-Qs) in rubber consumer products, including car tires, rubber belts, rubber gloves, rubber cables, and rubber hoses, to obtain information on the degree of weathering over time during their use. Additionally, we investigated the occurrences and sources of PPDs and PPD-Qs in dust samples collected from four typical urban environments (roads, parking lots, automotive repair shops, and residences). The detected compounds included the highly toxic N -(1,3-dimethylbutyl)- N ′-phenyl-1,4-phenylenediamine quinone, which can cause acute mortality of coho salmon ( Oncorhynchus kisutch ). Concentrations of PPDs in the automotive repair shops reached 56.0 μg/g, and were much higher than in the other environments, while the residential samples had the lowest contaminant concentrations. In road and residential samples, N , N ′-di-2-naphthyl- p -phenylenediamine accounted for 17 %–30 % of the PPDs, and may have originated from different sources. We preliminarily identified 32 transformation products, and 11 of these were N , N ′-di-2-naphthyl- p -phenylenediamine transformation products. The average daily intakes of PPDs and PPD-Qs were calculated to assess the health risks of dust exposure in each environment. Workers had high total intakes of PPD [60.3 ng/(kg day)] and PPD-Qs [20.1 ng/(kg day)], and were at some risk of occupational exposure. These results improve our understanding of the environmental occurrences, sources, transformation, and health risks of PPDs and PPD-Qs.
研究领域:
环境科学
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毒理学
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产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
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2020
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IF 7.632
Heng Liu,Qiulin Li,Bing-Huan Zhang,Long-Cheng Zhang,Guo-Rong Hou,Maowen Xu,Shu-Juan Bao
Fe–N–C catalysts exhibit promising activity toward the catalytic oxygen reduction reaction (ORR). However, applicability of such catalysts is limited by serious oxidative corrosion via the Fenton reaction. In this feature work, we prepared manganese–nitrogen species by pyrolyzing a bimetal CdMn and P-phenylenediamine organic complex (CdMn–PPD) under different atmospheres for the first time. The experimental results suggest that the carbonized atmosphere deeply affects the graphitization degree, pore structure of carbon, and the formation of Mn–N active sites. Of the three prepared catalysts, Mn@NPC–NH3 exhibited the greatest Mn–N and pyridinic N content and delivered excellent ORR activity (Eonset: 0.95 V, E1/2: 0.83 V). Even more impressive, the Fenton reaction was substantially restrained by this catalyst. Overall, the Mn@NPC–NH3 offers superior stability to that of Fe–N–C catalysts, providing new insight for further explorations of excellent non-noble metal ORR catalysts.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
JOURNAL OF ETHNOPHARMACOLOGY
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2015
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IF 2.998
Hui-Hui Xiao,Quan-Gui Gao,Ming-Xian Ho,Yan Zhang,Ka-Chun Wong,Yi Dai,Xin-Sheng Yao,Man-Sau Wong
Ethnopharmacological relevance Sambucus williamsii Hance (SWH), which belongs to the Caprifoliaceae family distributed in various regions of China, Korea and Japan, has been used as a folk medicine for treatment of bone and joint diseases in China for thousands of years. In previous studies, SWH was shown to possess anti-osteoporosis, healing fracture, anti-inflammatory and analgesic activities. Our previous studies showed that SWH extract effectively suppressed ovariectomy-induced increase in bone turnover and improved bone mineral density and bone biomechanical strength in rats as well as in mice. An 8- O -4′ norlignan, (7 R ,8 S )-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]-1,3-propanediol (PPD) was previously isolated and identified as the bioactive ingredient in SWH. The present study aimed to characterize the bone protective effects as well as its mechanism of actions in osteoblasts. Materials and methods Bone protective actions of PPD on different cells were determined by proliferation assay, alkaline phosphatase (ALP) activity assay, calcium deposition as well as real-time reverse transcriptase-polymerase chain reaction (RT-PCR). In addition, estrogen receptor (ER) antagonist ICI182,780 and mitogen-activated protein kinase kinase (MEK) inhibitor U0126 blocking assays, competitive ER radioligand binding assay, ERE-dependent luciferase reporter assay and immunoblotting were used to determine if PPD activated ER and if the effects of PPD on osteoblastic functions were ER dependent. Results PPD exerted anabolic effects in osteoblasts and its effects were abolished by co-incubation with ICI182,780 or U0126. PPD induced mRNA expressions of Runx2, ALP, osteocalcin, and increased the ratio of osteoprotegerin/receptor activator of nuclear factor κB (OPG/RANKL). PPD failed to bind to either ERα or ERβ and did not activate ERE-luciferase activity via ER. PPD induced the phosphorylation of extracellular regulated kinases (ERK) and its effect was completely abolished by U0126. It also induced the phosphorylation of ERα at serine 118. Conclusion These data show that PPD is a bioactive compound in SWH that exerts oestrogen-like actions in osteoblast-like cells via ligand-independent, estrogen response element (ERE)-independent and mitogen-activated protein (MAP) Kinase-mediated rapid nongenomic ER signaling pathway.
研究领域:
民族药理学
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分子生物学
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骨代谢研究
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DOI
PubMed
高影响因子
MOLECULES
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2023
·Vol. 28
·期 3
·1122
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IF 4.6
Juan He,Xiaomin Xu,Hainan Sun,Tengfei Miao,Meisheng Li,Shouyong Zhou,Wei Zhou
The harmful effects on the human body from p-phenylenediamine (PPD) in hair dyes can cause allergies and even cancer. Therefore, it is particularly important to accurately control and detect the content of PPD in our daily products and environment. Here, a small amount of non-metallic elemental P doped in perovskite oxide of SrCoO3−δ(SC) forms a good catalytic material, SrCo0.95P0.05O3−δ(SCP), for PPD detection. The improved performance compared with that of the parent SC can be attributed to three contributing factors, including a larger amount of highly oxidative oxygen species O22−/O−, better electrical conductivity, and more active sites on the P5+-oxygen bonds of SCP. Moreover, the lattice oxygen mechanism (LOM) with highly active species of lattice O vacancies and adsorbed –OO for electrocatalytic oxidation of PPD by the SCP/GCE (glass carbon electrode) sensor is proposed in our work. More importantly, the SCP/GCE sensor exhibits good stability, a low limit of detection, and high reliability (error < 5.78%) towards PPD determination in real samples of hair dyes, suggesting the substantial research potential for practical applications.Keywords:lattice oxygen;phosphorus-doped SrCo0.95P0.05O3−δ;p-phenylenediamine (PPD);electrochemical sensors;hair dyes
研究领域:
材料科学
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环境科学
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分析化学
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产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2022
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IF 10.753
Xin Hua,Xiao Feng,Geyu Liang,Jie Chao,Dayong Wang
2-((4-Methylpentan-2-yl)amino)-5-(phenylamino)cyclohexa-2,5-diene-1,4-dione (6-PPDQ) is the ozonation product of 6-PPD, a commonly used tire preservative. Although the 6-PPDQ has been frequently detected in different environmental ecosystems, its long-term effects on organisms remain still largely unknown. We here used Caenorhabditis elegans as an experimental animal to investigate the toxic effect of prolonged exposure to 6-PPDQ (0.1–100 μg/L). After the exposure, we found that 100 μg/L 6-PPDQ caused the lethality . We further selected concentrations of 0.1–10 μg/L to examine the possible intestinal toxicity induced by 6-PPDQ. Although 0.1–10 μg/L 6-PPDQ could not influence intestinal morphology, the intestinal permeability was significantly enhanced by 1–10 μg/L 6-PPDQ as indicated by erioglaucine disodium staining. In addition, the expression of intestinal fatty acid transporter ACS-22 governing functional state of intestinal barrier was decreased by exposure to 1–10 μg/L 6-PPDQ. Meanwhile, intestinal reactive oxygen species (ROS) production was induced by 0.1–10 μg/L 6-PPDQ and lipofuscin accumulation reflected by intestinal autofluorescence was activated by 1–10 μg/L 6-PPDQ. Accompanied with activation of intestinal oxidative stress , expressions of some anti-oxidation related genes ( ctl-2 , sod-2 , sod-3 , and sod-4 ) were significantly increased by 0.1–10 μg/L 6-PPDQ. Moreover, intestinal RNAi of acs-22 strengthened the susceptibility of nematodes to intestinal toxicity of 6-PPDQ. Therefore, considering that the environmentally relevant concentrations of 6-PPDQ were ≤10 μg/L, our data suggested that long-term exposure to 6-PPDQ at environmentally relevant concentrations potentially results in intestinal toxicity by disrupting functional state of intestinal barrier in organisms.
研究领域:
环境毒理学
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分子生物学
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生物化学
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产品关联
DOI
PubMed
高影响因子
Food Bioscience
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2024
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IF 4.8
Yanbo Hu,Yiming Li,Yuzhu Shen,Baochun Zhang,Jiaxin Liu,Yi Cao,Jun Zhao
In this study, six rare protopanaxadiol (PPD)-type ginsenosides, namely, F2, CK, C-Mc1, C-Mc, CO, and CY, were prepared using enzymatic hydrolysis. Firstly, major (PPD)-type ginsenosides, including Rb1, Rb2, Rc, and Rd, were biotransformed by employing single and combined β-glucosidases BaBgl1A and BaBgl3A. Thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) analyses revealed that ginsenosides F2, CO, and C-Mc1 could be produced by BaBgl1A, while rare ginsenosides CK, CY, and C-Mc could be produced by the combined use of BaBgl1A and BaBgl3A. Furthermore, optimal preparation conditions for these rare ginsenosides were elucidated, with yields exceeding 76.34%. Additionally, large quantities of rare ginsenosides were prepared to determine their structures. Characteristic absorption peaks in 13 C NMR spectra and ion peaks in MALDI-TOF-MS suggested that the six high-purity rare ginsenosides (i.e., F2, CO and C-Mc1, CK, CY, and C-Mc) could be produced at high-efficiency. The findings of this study offer insights into novel enzymolysis methods for the targeted preparation of rare PPD-type ginsenosides, thus widening the range of raw materials that could be directed to in-depth biological activity research.
研究领域:
生物化学
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药理学
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生物技术
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DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
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2023
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IF 12.6
Caixia Sun,Xue Zhang,Hao Huang,Ya Liu,Xianwei Mo,Yufei Feng,Jiahong Wang,Wenhua Zhou,Paul K. Chu,Xue-Feng Yu,Wenxin Liu
Nanozymes with enzyme-like characteristics have drawn wide interest but the catalytic activity and substrate selectivity of nanozymes still need improvement. Herein, Se-vacancy-rich TiSe 2-x @Au nanocomposites are designed and demonstrated as nanozymes. The TiSe 2-x @Au nanocomposites show excellent peroxidase-like activity and the chromogenic substrate p-phenylenediamine (PPD) can be selectively oxidized to compounds that exhibit an absorption peak at 413 nm that differs from that of self-oxidation or generally oxidized species, suggesting high catalytic activity and strong substrate selectivity. Theoretical calculations reveal that the PPD adsorption geometry at Se vacancies with an adsorption energy of −3.00 eV shows a unique spatial configuration and charge distribution , thereby inhibiting the free reaction and promoting both the activity and selectivity in PPD oxidation . The TiSe 2-x @Au colorimetric system exhibits a wide linear range of 0.015 mM–0.6 mM and a low detection limit of 0.0037 mM in the detection of glucose. The blood glucose detection performance for human serum samples is comparable to that of a commercial glucose meter in the hospital (relative standard deviation < 6%). Our findings demonstrate a new strategy for rapid and accurate detection of blood glucose and our results provide insights into the future design of nanozymes.
研究领域:
纳米技术
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生物催化
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分析化学
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材料科学
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生物化学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）