VIBRATIONAL SPECTROSCOPY
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2022
·
IF 2.382
Yiming Jia,Liangshuai Zhang,Yuan Xu,Lin Ye,Laiyuan Gu,Lin Chang,Wei Wang,Yujie Dai,Jiujiang Bai
In this study, we conducted diagnostic research on a precious Yuan dynasty tomb mural painting (A.D.1271–1368) excavated in Chongqing, 2005. To restore the painting, the painting technique and the artwork's preservation state were investigated through optical microscope (OM), portable X-ray fluorescence (p-XRF), micro-Raman spectroscopy (μ-Raman), macro-Fourier transform infrared spectroscopy (macro-FTIR), and X-ray powder diffraction (XRD) analyses. During this process, the coarse ground, fine ground and painting layer were characterized and analyzed. Experimental results show that the compositions of coarse ground are calcite and soil, while fine ground mainly consists of calcite and a few amounts of silicate. We also investigated and identified the pigments and binders used for the painting layers, which revealed that carbon black was used for the black pigment, cinnabar, red ochre and small amounts of red lead were used for the red pigments. To further investigate the distribution of materials in cross-sections with special attention to trace presented organic material, a FPA detector was used for imaging coupled with a large radius germanium crystal equipped attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. It has been found that the protein may be used as the binder and organic additive in mural painting. Our work enhances the understanding of the mural painting technique of the Yuan dynasty and also provides a reference for the future restoration work of paintings.
研究领域:
文物保护
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考古学
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材料科学
✓ 已验证
DOI
高影响因子
MOLECULES
·
2018
·Vol. 23
·期 10
·2518
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IF 3.098
Xuan Zheng,Hongwei Wang,Peng Zhang,Lin Gao,Ning Yan,Panpan Li,Xinmin Liu,Yongmei Du,Guoming Shen
Chaenomeles speciosa(Sweet) Nakai is a medicinal plant. Until date, there are no studies focusing on comparing the chemical profiles, antioxidant activity andα-glucosidase inhibitory activity of the dried fruits ofC. speciosafrom different production regions. In the study, we investigated the chemical components of dried fruits ofC. speciosafrom Yunnan, Chongqing, Zhejiang and Anhui provinces in China in relation to the antioxidant activity andα-glucosidase inhibitory activity.C. speciosafrom Yunnan had higher total flavonoid (47.92 ± 3.79 mg/g), total polyphenol (29.15 ± 0.29 mg/g) and polysaccharide (27.60 ± 1.56 mg/g) contents than plants from other production areas. Samples from Yunnan, Zhejiang and Anhui (all > 3200 mg/kg) had higher free amino acid contents than those from Chongqing (2286.66 mg/kg). Oleanolic acid and ursolic acid levels were highest in samples from Zhejiang (555.98 ± 20.88 μg/g) and Anhui (321.06 ± 14.64 μg/g), respectively.C. speciosafrom Chongqing had low total flavonoid, total polyphenol, polysaccharide, free amino acid, oleanolic acid and ursolic acid contents but high levels of palmitic acid (12.04 ± 0.02 mg/g) and stearic acid (2.23 ± 0.08 mg/g). Among four production areas, Yunnan represented the highest antioxidant activity andα-glucosidase inhibitory activity. In addition, correlation analysis revealed that total flavonoid, total polyphenol, polysaccharide and ursolic acid were the major components responsible for the antioxidant activity ofC. speciosa, while total flavonoid and polysaccharide were the main contributors forα-glucosidase inhibitory activity of the plant. These results would be helpful for evaluating the quality ofC. speciosain the different production areas.Keywords:Chaenomeles speciosa;chemical composition;antioxidant activity;α-glucosidase inhibitory activity
研究领域:
药用植物学
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植物化学
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药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Food Measurement and Characterization
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2020
·Vol. 14
·期 4
·2010-2020
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IF 1.648
Huang Shuai,Wang Qiang,Wang Yaosong,Ying Ruifeng,Fan Gongjian,Huang Meigui,Agyemang Mary
This study characterized the quality, composition and antioxidant activities of olive oil from four olive varieties grown in Chongqing, southwest of China. With the fruit skin turned from green to semi black, the percentage of oleic acid decreased while the percentage of linoleic acid increased. The highest concentrations of total phenolic content, total flavonoid content and total antioxidant activity were found in the Coratina olive oils, in which the lowest content of oleuropein was also observed. Significant differences of fatty acid composition at sn-2 position were observed among the varieties, with the percentage of oleic acid at sn-2 position in Picual olive oils were significantly higher than that of other varieties ( p < 0.05). In addition, the different varieties of olive oil samples were divided into three categories by principal component analysis (PCA), and the quality of Coratina olive oils were greatly affected by fruit ripening stage. With the fruit ripening, the levels of hydroxytyrosol, rutin, total phenolics, total flavonoids and antioxidant activities in Coratina olive oil all declined. This work can provide guidance for the harvesting time and processing of olives in Chongqing.
研究领域:
农业
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食品科学
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化学
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营养学
✓ 已验证
产品关联
DOI
高影响因子
Foods
·
2024
·Vol. 13
·期 6
·865
·
IF 4.7
Yiwen Miao,Lilei Wang,Fei Bai,Shuting Zheng,Jingna Yan,Hao Wei,Qing Meng,Huarong Tong
This study aims to investigate the relationship between the grades of Tuo tea and the quality of compounds. A combination of artificial sensory evaluation, intelligent sensory technologies (electronic nose and electronic tongue), gas chromatography–mass spectrometry (GC-MS), high-performance liquid chromatography (HPLC), chemical–physical analysis, and multivariate statistical analysis were employed to examine the differences among three grades of Tuo tea (SG, 1G, and 2G). The results of artificial sensory evaluation, electronic tongue, and electronic nose revealed that the aroma and taste of different grades of Tuo tea varied greatly. A total of 112 volatile compounds and 44 non-volatile compounds were identified. In order to elucidate the key components that cause differences in the quality of Tuo tea, 2 partial least squares discriminant analysis (PLS-DA) models with excellent parameters (volatile, R2Y = 0.999 and Q2= 0.996; non-volatile, R2Y = 0.992 and Q2= 0.972) were established. A total of 80 key differential volatile compounds were identified with the double selection criterion of variable importance in projection (VIP) greater than 1 andp< 0.05. Among these, 43 compounds with OAV > 1 were further identified as the odor-active compounds in all three grades of Tuo. Moreover, 22 key non-volatile compounds that contribute to the quality differences have been screened out. This investigation implied that the volatile and non-volatile compounds of Tuo tea could serve as indicators of its quality. The results provided a new approach to distinguish the grades of Tuo tea.
研究领域:
食品科学
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分析化学
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感官科学
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农业化学
✓ 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）