In this paper,we prepared the nanoparticle drug carrier system between nanoparticles chitosan and Epigallocatechin-3 O-gallate(EGCG)for breast cancer cell inhibiting application.For this drug carrier system,chitosan a...In this paper,we prepared the nanoparticle drug carrier system between nanoparticles chitosan and Epigallocatechin-3 O-gallate(EGCG)for breast cancer cell inhibiting application.For this drug carrier system,chitosan acts as a carrier and EGOG as a drug.Which were systematically characterized and thoroughly evaluated in terms of their inhibition rate and biocompatibility.We also did a cell scratch test and the result indicated that the chitosan EGCG nanoparticles have inhibitory effect on the growth of breast cancer cells.The inhibition rate could reach up to 21.91%.This work revealed that the modification of nanopartidles paved a way for specific biomedical applications.展开更多
Lipophilic tea polyphenols (LTP) were prepared by catalytic esterification of green tea polyphenols (GTP) with hexadecanoyl chloride. A novel long chain acyl derivative of epigallocatechin 3 o gallate (EGCG) ...Lipophilic tea polyphenols (LTP) were prepared by catalytic esterification of green tea polyphenols (GTP) with hexadecanoyl chloride. A novel long chain acyl derivative of epigallocatechin 3 o gallate (EGCG) was first isolated from purification of LTP by high speed countercurrent chromatography (HSCCC) using a solvent system composed of n hexane ethyl acetate methanol water (1:1:1:1, v/v). The molecular structure of the acyl derivative, Epigallocatechin 3 O gallate 4′ O hexadecanate , was elucidated by means of elemental analysis, IR, 1H NMR and MS spectra.展开更多
Epigallocatechin-3-O-（3-O-methyl） gallate（EGCG3＂Me） present in leaves of Camellia sinensis has many beneficial biological activities for human health. However, EGCG3＂Me occurs naturally in tea leaves in extremel...Epigallocatechin-3-O-（3-O-methyl） gallate（EGCG3＂Me） present in leaves of Camellia sinensis has many beneficial biological activities for human health. However, EGCG3＂Me occurs naturally in tea leaves in extremely limited quantities. Finding an enzyme from C. sinensis to catalyze the synthesis of EGCG3＂Me is an alternative method to make up for the scarcity of EGCG3＂Me in natural situations. In the present study, a complementary DNA（c DNA） encoding region and genomic DNA of the caffeoyl-coenzyme A O-methyltransferase（CCo AOMT） gene were isolated from C. sinensis（designated Cs CCo AOMT）. Nucleotide sequence analysis of Cs CCo AOMT revealed an open reading frame of 738 bp that encodes a polypeptide with a predicted molecular weight of 28 k Da, which correlated well with the results of sodium dodecyl sulfate-polyacrylamide gel electrophoresis（SDS-PAGE）. The full-length DNA sequence（2678 bp） contained five exons and four introns. The deduced amino acid sequence of Cs CCo AOMT shared 92% identity with CCo AOMTs from Codonopsis lanceolata and Betula luminifera. The catalytic activity of Cs CCo AOMT was analyzed. Three monomethylated epigallocatechin-3-O-gallate（EGCG） compounds（EGCG4＂Me, EGCG3＂Me, and EGCG3＇Me） were produced by Cs CCo AOMT with K m in the micromolar range. Real-time polymerase chain reaction（RT-PCR） experiments indicated that the Cs CCo AOMT transcript was present at low levels during the early stages of leaf maturity（the first leaf and bud on a shoot） but the relative expression was augmented at advanced stages of leaf maturity（the third or fourth leaf on a shoot）, which accorded well with changes in EGCG3＂Me content in fresh leaves. Hence, we concluded that Cs CCo AOMT catalyzes the syntheses of methylated EGCGs.展开更多
目的:评价表没食子儿茶素没食子酸酯(EGCG)及其甲基化修饰物(EGCG-3Me)改性粘接剂对根管牙本质粘接界面稳定性的作用。方法:将质量浓度为400μg/ml的EGCG及EGCG-3Me添加到全酸蚀粘接剂Single Bond 2(SB2)中,制备改性粘接剂E-SB2及E3-SB2...目的:评价表没食子儿茶素没食子酸酯(EGCG)及其甲基化修饰物(EGCG-3Me)改性粘接剂对根管牙本质粘接界面稳定性的作用。方法:将质量浓度为400μg/ml的EGCG及EGCG-3Me添加到全酸蚀粘接剂Single Bond 2(SB2)中,制备改性粘接剂E-SB2及E3-SB2,SB2为对照组。激光共聚焦显微镜和分光光度法检测改性粘接剂抗粪肠球菌的性能。微拉曼光谱仪检测粘接剂双键转化率。制备纤维桩粘接试件,用于即刻和老化后的微推出实验。结果:改性粘接剂可以抑制粪肠球菌生物膜形成,且EGCG-3Me作用更显著。改性粘接剂与SB2的双键转化率和即刻微推出粘接强度差异无显著性(P>0.05)。老化后改性粘接剂的微推出粘接强度显著高于SB2(P<0.05)。结论:EGCG和EGCG-3Me改性的粘接剂均可抑制粪肠球菌增殖并提高树脂-根管牙本质粘接界面稳定性,EGCG-3Me抗菌性能较佳。展开更多
将质量浓度为400μg/mL的EGCG及EGCG-3Me添加到全酸蚀粘接剂Single Bond 2(SB2)中,制备改性粘接剂E-SB2及E3-SB2,SB2为对照组。激光共聚焦显微镜和分光光度法检测改性粘接剂抗粪肠球菌的性能;微拉曼光谱仪检测粘接剂双键转化率;制备纤...将质量浓度为400μg/mL的EGCG及EGCG-3Me添加到全酸蚀粘接剂Single Bond 2(SB2)中,制备改性粘接剂E-SB2及E3-SB2,SB2为对照组。激光共聚焦显微镜和分光光度法检测改性粘接剂抗粪肠球菌的性能;微拉曼光谱仪检测粘接剂双键转化率;制备纤维桩粘接试件,用于即刻和老化后的微推出实验。结果表明,改性粘接剂可以抑制粪肠球菌生物膜形成,且EGCG-3Me作用更显著;改性粘接剂与SB2的双键转化率和即刻微推出粘接强度差异无显著性(P>0.05);老化后改性粘接剂的微推出粘接强度显著高于SB2(P<0.05)。展开更多
The binding of （-）-epigallocatechin-3-O-gallate （EGCG） to bovine serum albumin （BSA） were investigated for the first time with spectral methods, including fluorescence and absorption spectrometry under simulativ...The binding of （-）-epigallocatechin-3-O-gallate （EGCG） to bovine serum albumin （BSA） were investigated for the first time with spectral methods, including fluorescence and absorption spectrometry under simulative physiological conditions. A strong fluorescence quenching reaction of EGCG to BSA was observed. It was proved that the fluorescence quenching of BSA by addition of EGCG was a result of the formation of EGCG-BSA complex. The binding constant K and the number of binding sites n were determined at physiological conditions and three different temperatures with fluorescence quenching method. The binding distance R and transfer efficiency E between BSA and EGCG were also obtained according to Forster theory of non-radiation energy transfer. The effects of Al^3＋, Cu^2＋, Mg^2＋ and Fe^2＋ on the binding constant between EGCG and BSA were studied at 298 K. The effect of EGCG on the conformation of BSA was also analyzed by synchronous fluorescence spectroscopy. PACS. 21. 10. Dr; 32. 50. ＋d; 32. 30. Jc; 82.80. Dx展开更多
基金the support of the National Natural Science Foundation of China(NSFC Nos.61722508 and 11305020)Nanophotonics and Biophotonics Key Laboratory of Jilin Province,P.R.China(20140622009JC)and(14GH005).
文摘In this paper,we prepared the nanoparticle drug carrier system between nanoparticles chitosan and Epigallocatechin-3 O-gallate(EGCG)for breast cancer cell inhibiting application.For this drug carrier system,chitosan acts as a carrier and EGOG as a drug.Which were systematically characterized and thoroughly evaluated in terms of their inhibition rate and biocompatibility.We also did a cell scratch test and the result indicated that the chitosan EGCG nanoparticles have inhibitory effect on the growth of breast cancer cells.The inhibition rate could reach up to 21.91%.This work revealed that the modification of nanopartidles paved a way for specific biomedical applications.
文摘Lipophilic tea polyphenols (LTP) were prepared by catalytic esterification of green tea polyphenols (GTP) with hexadecanoyl chloride. A novel long chain acyl derivative of epigallocatechin 3 o gallate (EGCG) was first isolated from purification of LTP by high speed countercurrent chromatography (HSCCC) using a solvent system composed of n hexane ethyl acetate methanol water (1:1:1:1, v/v). The molecular structure of the acyl derivative, Epigallocatechin 3 O gallate 4′ O hexadecanate , was elucidated by means of elemental analysis, IR, 1H NMR and MS spectra.
基金supported by the Zhejiang Provincial Natural Science Foundation of China(No.Y3080088)the National Natural Science Foundation of China(No.30972404)+1 种基金the Earmarked Fund for China Agricultural Research System(No.CARS-23)the Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(No.CAAS-ASTIP-2014-TRICAAS-OX)
文摘Epigallocatechin-3-O-（3-O-methyl） gallate（EGCG3＂Me） present in leaves of Camellia sinensis has many beneficial biological activities for human health. However, EGCG3＂Me occurs naturally in tea leaves in extremely limited quantities. Finding an enzyme from C. sinensis to catalyze the synthesis of EGCG3＂Me is an alternative method to make up for the scarcity of EGCG3＂Me in natural situations. In the present study, a complementary DNA（c DNA） encoding region and genomic DNA of the caffeoyl-coenzyme A O-methyltransferase（CCo AOMT） gene were isolated from C. sinensis（designated Cs CCo AOMT）. Nucleotide sequence analysis of Cs CCo AOMT revealed an open reading frame of 738 bp that encodes a polypeptide with a predicted molecular weight of 28 k Da, which correlated well with the results of sodium dodecyl sulfate-polyacrylamide gel electrophoresis（SDS-PAGE）. The full-length DNA sequence（2678 bp） contained five exons and four introns. The deduced amino acid sequence of Cs CCo AOMT shared 92% identity with CCo AOMTs from Codonopsis lanceolata and Betula luminifera. The catalytic activity of Cs CCo AOMT was analyzed. Three monomethylated epigallocatechin-3-O-gallate（EGCG） compounds（EGCG4＂Me, EGCG3＂Me, and EGCG3＇Me） were produced by Cs CCo AOMT with K m in the micromolar range. Real-time polymerase chain reaction（RT-PCR） experiments indicated that the Cs CCo AOMT transcript was present at low levels during the early stages of leaf maturity（the first leaf and bud on a shoot） but the relative expression was augmented at advanced stages of leaf maturity（the third or fourth leaf on a shoot）, which accorded well with changes in EGCG3＂Me content in fresh leaves. Hence, we concluded that Cs CCo AOMT catalyzes the syntheses of methylated EGCGs.
文摘目的:评价表没食子儿茶素没食子酸酯(EGCG)及其甲基化修饰物(EGCG-3Me)改性粘接剂对根管牙本质粘接界面稳定性的作用。方法:将质量浓度为400μg/ml的EGCG及EGCG-3Me添加到全酸蚀粘接剂Single Bond 2(SB2)中,制备改性粘接剂E-SB2及E3-SB2,SB2为对照组。激光共聚焦显微镜和分光光度法检测改性粘接剂抗粪肠球菌的性能。微拉曼光谱仪检测粘接剂双键转化率。制备纤维桩粘接试件,用于即刻和老化后的微推出实验。结果:改性粘接剂可以抑制粪肠球菌生物膜形成,且EGCG-3Me作用更显著。改性粘接剂与SB2的双键转化率和即刻微推出粘接强度差异无显著性(P>0.05)。老化后改性粘接剂的微推出粘接强度显著高于SB2(P<0.05)。结论:EGCG和EGCG-3Me改性的粘接剂均可抑制粪肠球菌增殖并提高树脂-根管牙本质粘接界面稳定性,EGCG-3Me抗菌性能较佳。
文摘将质量浓度为400μg/mL的EGCG及EGCG-3Me添加到全酸蚀粘接剂Single Bond 2(SB2)中,制备改性粘接剂E-SB2及E3-SB2,SB2为对照组。激光共聚焦显微镜和分光光度法检测改性粘接剂抗粪肠球菌的性能;微拉曼光谱仪检测粘接剂双键转化率;制备纤维桩粘接试件,用于即刻和老化后的微推出实验。结果表明,改性粘接剂可以抑制粪肠球菌生物膜形成,且EGCG-3Me作用更显著;改性粘接剂与SB2的双键转化率和即刻微推出粘接强度差异无显著性(P>0.05);老化后改性粘接剂的微推出粘接强度显著高于SB2(P<0.05)。
文摘The binding of （-）-epigallocatechin-3-O-gallate （EGCG） to bovine serum albumin （BSA） were investigated for the first time with spectral methods, including fluorescence and absorption spectrometry under simulative physiological conditions. A strong fluorescence quenching reaction of EGCG to BSA was observed. It was proved that the fluorescence quenching of BSA by addition of EGCG was a result of the formation of EGCG-BSA complex. The binding constant K and the number of binding sites n were determined at physiological conditions and three different temperatures with fluorescence quenching method. The binding distance R and transfer efficiency E between BSA and EGCG were also obtained according to Forster theory of non-radiation energy transfer. The effects of Al^3＋, Cu^2＋, Mg^2＋ and Fe^2＋ on the binding constant between EGCG and BSA were studied at 298 K. The effect of EGCG on the conformation of BSA was also analyzed by synchronous fluorescence spectroscopy. PACS. 21. 10. Dr; 32. 50. ＋d; 32. 30. Jc; 82.80. Dx
