Analytical difficulties encountered in the determination of ethyl carbamate, a known cancinogen, in a wide variety of wines and spirits have been overcome by spe- cific, sensitive GC/GC and CC/CC/MS methods with a rel...Analytical difficulties encountered in the determination of ethyl carbamate, a known cancinogen, in a wide variety of wines and spirits have been overcome by spe- cific, sensitive GC/GC and CC/CC/MS methods with a relatively shorter extraction procedure. The lowest detection limits were estimated to be 0. 1 and 0. 01μg/L for GC/GC and GC/GC/MS respectively. The RSD of the GC/GC method was 2. 5%.展开更多
The present work sought to characterize the cyanogenic glycoside dhurrin in five sugarcane varieties and to determine its possible relationship with the formation of ethyl carbamate in cachaca. For each variety, metha...The present work sought to characterize the cyanogenic glycoside dhurrin in five sugarcane varieties and to determine its possible relationship with the formation of ethyl carbamate in cachaca. For each variety, methanol, ethyl acetate and hexane extracts were prepared and submitted to thin layer chromatography. Chromatographic spots were revealed with iodine vapors. The physical and chemical parameters of the spirits produced from the five different varieties of sugar cane and by different production processes were within the legal limits. Although not exceeding the limit for ethyl carbamate, a significant variation in the final concentration of this compound was observed for each sample analyzed. The Rf values for the dhurrin standard and for the sugarcane variety SP 83-2847 were equal, similar to those for SP 80-3280 and CTC 11 and different from the Rf values for the RB 86-7515 and IAC 86-2480 samples.展开更多
分析10%乙羧氟草醚EC对大豆田阔叶杂草的防除效果和最佳使用剂量,对其进行了田间药效试验。结果表明,10%乙羧氟草醚EC 300~1 200 m L/hm2处理,药后40 d对大豆田阔叶杂草的株防效达91.49%~99.87%,鲜重防效达95.65%~99.94%,可较好地控制...分析10%乙羧氟草醚EC对大豆田阔叶杂草的防除效果和最佳使用剂量,对其进行了田间药效试验。结果表明,10%乙羧氟草醚EC 300~1 200 m L/hm2处理,药后40 d对大豆田阔叶杂草的株防效达91.49%~99.87%,鲜重防效达95.65%~99.94%,可较好地控制大豆田野苋菜、马齿苋的为害,在杂草3~5叶期使用,用量以600~900 m L/hm2为宜。展开更多
为明确17.5%精喹禾灵EC对大豆田禾本科杂草的防除效果及其使用的安全性,在田间设17.5%精喹禾灵EC每公顷26.25、39.375、52.5、78.75 g 4个处理,以5%精喹禾灵EC 45 g/hm^2为对照药剂,以人工锄草和清水喷雾为对照。结果表明,17.5%精喹禾...为明确17.5%精喹禾灵EC对大豆田禾本科杂草的防除效果及其使用的安全性,在田间设17.5%精喹禾灵EC每公顷26.25、39.375、52.5、78.75 g 4个处理,以5%精喹禾灵EC 45 g/hm^2为对照药剂,以人工锄草和清水喷雾为对照。结果表明,17.5%精喹禾灵EC对大豆田马唐、稗草具有很好的防效,可以在生产上推广使用。展开更多
Wax apple(Syzygium samarangense)has received growing research interest for its high nutritional and medicinal value due to its constituents such as polysaccharide,organic acids,flavonoids,minerals,and other substances...Wax apple(Syzygium samarangense)has received growing research interest for its high nutritional and medicinal value due to its constituents such as polysaccharide,organic acids,flavonoids,minerals,and other substances.In this study,wax apple polysaccharide(WAP)was isolated from this plant and its protective effect against ethyl carbamate(EC)-induced oxidative damage was evaluated in human hepatocytes(L02 cells).Firstly,a series of analyses such as high-performance liquid chromatography(HPLC),high-performance gel permeation chromatography(HPGPC),Fourier transform infrared spectroscopy(FT-IR),gas chromatography/mass spectrometry(GC/MS),and 1H and 13C nuclear magnetic resonance(NMR)were conducted to identify the structure of,in vitro cell experiments were performed to verify the protective effects of WAP against EC-induced cytotoxicity,genotoxicity,and oxidative damage in L02 cells.Our results revealed that WAP is composed of mannose,rhamnose,glucuronic acid,galacturonic acid,glucose,galactose,arabinose,and fucose in a molar ratio of 2.20:3.94:4.45:8.56:8.86:30.82:39.78:1.48.Using a combination of methylation and NMR spectroscopic analysis,the primary structure of WAP was identified as Araf-(1→,Glcp-(1→,→2)-Araf-(1→,→3)-Galp-(1→,→3)-Araf-(1→,and→6)-Galp-(1→.Cell experiments indicated that WAP exhibited significant protective effects on EC-treated L02 cells via suppressing cytotoxicity and genotoxicity,reducing reactive oxygen species(ROS)and O2?-formation,as well as improving mitochondrial membrane potential(MMP)and glutathione(GSH).In a nutshell,WAP has the potential as an important therapeutic agent or supplement for hepatic oxidative damage.Meanwhile,further studies are needed to prove the above effects in vivo at the biological and clinical levels.展开更多
文摘Analytical difficulties encountered in the determination of ethyl carbamate, a known cancinogen, in a wide variety of wines and spirits have been overcome by spe- cific, sensitive GC/GC and CC/CC/MS methods with a relatively shorter extraction procedure. The lowest detection limits were estimated to be 0. 1 and 0. 01μg/L for GC/GC and GC/GC/MS respectively. The RSD of the GC/GC method was 2. 5%.
基金the Conselho Nacional de Desenvolvimento Cientifico e Tecnologico(CNPQ),the Fundacao de Amparo a Pesquisa do Estado de Minas Gerais(FAPEMIG),and the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior(CAPES)for financial support.
文摘The present work sought to characterize the cyanogenic glycoside dhurrin in five sugarcane varieties and to determine its possible relationship with the formation of ethyl carbamate in cachaca. For each variety, methanol, ethyl acetate and hexane extracts were prepared and submitted to thin layer chromatography. Chromatographic spots were revealed with iodine vapors. The physical and chemical parameters of the spirits produced from the five different varieties of sugar cane and by different production processes were within the legal limits. Although not exceeding the limit for ethyl carbamate, a significant variation in the final concentration of this compound was observed for each sample analyzed. The Rf values for the dhurrin standard and for the sugarcane variety SP 83-2847 were equal, similar to those for SP 80-3280 and CTC 11 and different from the Rf values for the RB 86-7515 and IAC 86-2480 samples.
文摘分析10%乙羧氟草醚EC对大豆田阔叶杂草的防除效果和最佳使用剂量,对其进行了田间药效试验。结果表明,10%乙羧氟草醚EC 300~1 200 m L/hm2处理,药后40 d对大豆田阔叶杂草的株防效达91.49%~99.87%,鲜重防效达95.65%~99.94%,可较好地控制大豆田野苋菜、马齿苋的为害,在杂草3~5叶期使用,用量以600~900 m L/hm2为宜。
文摘为明确17.5%精喹禾灵EC对大豆田禾本科杂草的防除效果及其使用的安全性,在田间设17.5%精喹禾灵EC每公顷26.25、39.375、52.5、78.75 g 4个处理,以5%精喹禾灵EC 45 g/hm^2为对照药剂,以人工锄草和清水喷雾为对照。结果表明,17.5%精喹禾灵EC对大豆田马唐、稗草具有很好的防效,可以在生产上推广使用。
基金supported by the Zhejiang Provincial Key R&D Program of China(No.2021C02018)the Open Project of Wencheng Joint Research Center of Big Health Industry of Zhejiang University(No.Zdwc2205),China.
文摘Wax apple(Syzygium samarangense)has received growing research interest for its high nutritional and medicinal value due to its constituents such as polysaccharide,organic acids,flavonoids,minerals,and other substances.In this study,wax apple polysaccharide(WAP)was isolated from this plant and its protective effect against ethyl carbamate(EC)-induced oxidative damage was evaluated in human hepatocytes(L02 cells).Firstly,a series of analyses such as high-performance liquid chromatography(HPLC),high-performance gel permeation chromatography(HPGPC),Fourier transform infrared spectroscopy(FT-IR),gas chromatography/mass spectrometry(GC/MS),and 1H and 13C nuclear magnetic resonance(NMR)were conducted to identify the structure of,in vitro cell experiments were performed to verify the protective effects of WAP against EC-induced cytotoxicity,genotoxicity,and oxidative damage in L02 cells.Our results revealed that WAP is composed of mannose,rhamnose,glucuronic acid,galacturonic acid,glucose,galactose,arabinose,and fucose in a molar ratio of 2.20:3.94:4.45:8.56:8.86:30.82:39.78:1.48.Using a combination of methylation and NMR spectroscopic analysis,the primary structure of WAP was identified as Araf-(1→,Glcp-(1→,→2)-Araf-(1→,→3)-Galp-(1→,→3)-Araf-(1→,and→6)-Galp-(1→.Cell experiments indicated that WAP exhibited significant protective effects on EC-treated L02 cells via suppressing cytotoxicity and genotoxicity,reducing reactive oxygen species(ROS)and O2?-formation,as well as improving mitochondrial membrane potential(MMP)and glutathione(GSH).In a nutshell,WAP has the potential as an important therapeutic agent or supplement for hepatic oxidative damage.Meanwhile,further studies are needed to prove the above effects in vivo at the biological and clinical levels.
