FIBERS AND POLYMERS
·
2016
·Vol. 17
·期 2
·305-309
·
IF 1.022
Yu Yalun,Cai Muyuan,Zhou Lan,Shao Jianzhong
The accumulation and autoxidation of residual oily soil from human sebum is regarded as a major reason for the aging and yellowing of clothing and household textiles. In this study, the yellowing degree of cotton fabrics soiled with human sebum components and aged under various environmental conditions (various temperatures, humidities and light intensities etc.) were investigated. The representative sebum components including olive oil, squalene, oleic acid and cottonseed oil were selected and their chemical changes were studied by FTIR analysis. The results showed that, olive oil, squalene, oleic acid and cottonseed oil could caused more significant fabric-yellowing than other components in human sebum, and the yellowing degree could become higher with increasing temperatures, humidities and/or light intensities of aging environments. The chemical structures of olive oil, squalene and oleic acid changed remarkably after aging treatment. The aging products contained hydroxyl groups and carbonyl groups, and the conjugated C=O group was considered to be the chemical species leading to the yellowing of sebum-soiled fabrics.
研究领域:
纺织科学
·
生物化学
✓ 已验证
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2020
·
IF 4.032
Qingkun Liu,Jia Li,Chuanbo Cong,Haomeng Cui,Lixin Xu,Ying Zhang,Xiaoyu Meng,Qiong Zhou
The research on the applicability of elastomeric sealing materials in geothermal environments has focused on changes in physical properties, and our understanding of the chemical changes remains lacking. This work investigates the thermal and thermo-oxidative aging behaviors of tetrafluoroethylene–propylene elastomer (FEPM) at temperatures above 300 °C. During thermal aging, the polypropylene (PP) molecular chain that is not adjacent to the polytetrafluoroethylene (PTFE) component breaks and thus causes the removal of partial saturated hydrocarbons. During thermo-oxidative aging, the appearance of O 2 promotes the oxidative scission of the PP component and the removal of the PTFE component, thereby generating new carbonyl-containing substances and double bonds. Therefore, the degrees of mechanical and thermal property damages caused by thermo-oxidative aging are much higher than those caused by thermal aging. In addition, the triallyl isocyanurate crosslinked structure degrades during thermal and thermo-oxidative aging, resulting in the destruction of the crosslinked network. The analysis of the degradation mechanism of FEPM allows chemical changes to be correlated with physical modifications and provides theoretical guidance for the future development of fluoroelastomers.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY
·
2021
·
IF 5.277
Chengcheng Zhang,Jianming Zhang,Daqun Liu
Zhacai is a traditional fermented vegetable that has been consumed in China for centuries. It is currently manufactured by spontaneous fermentation and therefore mostly relies on the activities of autochthonous microorganisms. Here, we characterized microbial community dynamics and associated biochemical changes in 12% salted Zhacai during a 90-day spontaneous fermentation process using high-throughput sequencing and chromatography-based approaches to identify associations between microorganisms and fermentation characteristics. Amplicon sequencing targeting bacterial 16S rRNA genes revealed that bacterial communities were dominated by halophilic bacteria (HAB, i.e., Halomonas and Idiomarina ) and lactic acid bacteria (LAB, i.e., Lactobacillus -related genera and Weissella ) after 30 days of fermentation. In addition, the relative abundances of the fungal genera Debaryomyces , Sterigmatomyces , and Sporidiobolus increased as fermentation progressed. Concomitantly, pH decreased while titratable acidity increased during fermentation, along with associated variation in biochemical profiles. Overall, the levels of organic acids (i.e., lactic and acetic acid), free amino acids (i.e., alanine, lysine, and glutamic acid), and volatiles (i.e., alcohols, esters, aldehydes, and ketones) increased in mature Zhacai. In addition, the abundances of Lactobacillus -related species, Halomonas spp., Idiomarina loihiensis , as well as that of the yeast Debaryomyces hansenii , were strongly correlated with increased concentrations of organic acids, amino acids, biogenic amines, and volatiles. This study provides new detailed insights into the succession of microbial communities and their potential roles in Zhacai fermentation.
研究领域:
食品科学
·
微生物学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2024
·
IF 3.8
Fan Xinyu,Zhou Lin,Xing Yanchao,Wang Liming,Choi Shin Sik,Zhang Zixin,Zhang Xu,Liu Caixiang,Zhu Yu,Fu Zhifei,Han Lifeng
The processing of traditional Chinese medicine (TCM) plays an important role in the clinical application, which usually has the function of "increasing efficiency and reducing toxicity". Polygonum multiflorum (PM) has been reported to induce hepatotoxicity, while it is believed that the toxicity is reduced after processing. Studies have shown that the hepatotoxicity of PM is closely related to the changes in chemical components before and after processing. However, there is no comprehensive investigation on the chemical changes of PM during the processing progress. In this research, we established a comprehensive method to profile both small molecule compounds and polysaccharides from raw and different processed PM samples. In detail, an online two-dimensional liquid chromatography coupled with quadrupole-orbitrap mass spectrometry (2D-LC/Q-Orbitrap MS) was utilized to investigate the small molecules, and a total of 150 compounds were characterized successfully. After multivariate statistical analysis, 49 differential compounds between raw and processed products were screened out. Furthermore, an accurate and comprehensive method for quantification of differential compounds in PM samples was established based on ultra-high performance liquid chromatography/Q-Orbitrap-MS (UHPLC/Q-Orbitrap-MS) within 16 min. In addition, the changes of polysaccharides in different PM samples were analyzed, and it was found that the addition of black beans and steaming times would affect the content and composition of polysaccharides in PM significantly. Our work provided a reference basis for revealing the scientific connotation of the processing technology and increasing the quality control and safety of PM. Graphical Abstract
研究领域:
药理学
·
分析化学
·
中医药
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2023
·
IF 8.9
Yu Xing,Jing Li,Jingjing Yang,Junyi Li,Weiyi Pang,Francis L. Martin,Li Xu
Humans are routinely exposed to nanoplastics (NPs) in various ways, and this exposure presents a significant health risk. Nevertheless, there remain gaps in our knowledge, particularly in the mechanisms of toxicity of NPs with different surface charges at very low environmental concentrations. Herein, a spectrochemical approach was used to profile the cytotoxicity of NPs with different surface charges in HepG 2 cells. It was found that all three NPs can cause some biomolecular alterations in cells, affecting cellular lipids, proteins, amino acids, and genetic material. Of these, PS and PS-COOH led to a non-linear dose-response, which may be related to a biphasic dose-response, whereas PS-NH 2 led to a linear dose-response with a gradual increase in toxicity with increasing exposure concentration. In addition, the spectroscopic results showed that surface modifications led to cellular biochemical changes and caused adverse biological effects, with PS-NH 2 exhibiting higher toxicity compared to PS or PS-COOH along with an inhibition of cell proliferation. Surprisingly PS-COOH, although considered the least toxic NP, appears to cause DNA damage. Overall, the toxic effects of different surface-modified NPs in cells were detected for the first time by applying spectrochemical techniques, and these findings provide important data towards understanding the emerging widespread environmental pollution of NPs and their effects on humans.
研究领域:
毒理学
·
细胞生物学
·
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Scientific Reports
·
2017
·Vol. 7
·期 1
·1-9
·
IF 4.259
Li Shan-Shan,Guan Qi-Yuan,Meng Gang,Chang Xiao-Feng,Wei Ji-Wu,Wang Peng,Kang Bin,Xu Jing-Juan,Chen Hong-Yuan
Better understanding the drug action within cells may extend our knowledge on drug action mechanisms and promote new drugs discovery. Herein, we studied the processes of drug induced chemical changes on proteins and nucleic acids in human breast adenocarcinoma (MCF-7) cells via time-resolved plasmonic-enhanced Raman spectroscopy (PERS) in combination with principal component analysis (PCA). Using three popular chemotherapy drugs (fluorouracil, cisplatin and camptothecin) as models, chemical changes during drug action process were clearly discriminated. Reaction kinetics related to protein denaturation, conformational modification, DNA damage and their associated biomolecular events were calculated. Through rate constants and reaction delay times, the different action modes of these drugs could be distinguished. These results may provide vital insights into understanding the chemical reactions associated with drug-cell interactions.
研究领域:
生物物理学
·
药学
·
细胞生物学
·
光谱学
✓ 已验证
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）