Comparative effects of food-derived polyphenols on the viability and apoptosis of a human hepatoma cell line (HepG2)

Consumption of fruits and vegetables, which are rich in polyphenols, has been associated with a reduced risk of chronic diseases such as cancer. Dietary polyphenols have antioxidant and antiproliferative properties that might explain their beneficial effect on cancer prevention. The aim of this study was to investigate the effects of different pure polyphenols [quercetin, chlorogenic acid, and (-)-epicatechin] and natural fruit extracts (strawberry and plum) on viability or apoptosis of human hepatoma HepG2 cells. The treatment of cells for 18 h with quercetin and fruit extracts reduced cell viability in a dose-dependent manner; however, chlorogenic acid and (-)-epicatechin had no prominent effects on the cell death rate. Similarly, quercetin and strawberry and plum extracts, rather than chlorogenic acid and (-)-epicatechin, induced apoptosis in HepG2 cells. Moreover, quercetin and fruit extracts arrested the G1 phase in the cell cycle progression prior to apoptosis. Quercetin and strawberry and plum extracts may induce apoptosis and contribute to a reduced cell viability in HepG2 cells.     

福建三种稻田土壤地力贡献率及氮磷钾适宜用量

通过４年定位施肥及１９８９年早稻氮，磷，钾配比试验结果表明，灰泥田地力贡献率４年总平均为５１．２６％，灰黄泥田为４３．９５％，黄泥田为３６．２３％，氮，磷，钾配比试验结果经过二次回归分析，得出３种稻田早稻最佳化肥用量（ｋｇ／ｈｍ＾２）依次是：灰泥田为Ｎ１３５．２，Ｐ２Ｏ５４０．０，Ｋ２Ｏ１２３．２，灰黄泥田为Ｎ１３５．２，Ｐ２Ｏ５４２．４Ｋ２Ｏ１１５．２黄泥田为Ｎ１２０．８，Ｐ２Ｏ５５２．８Ｋ２Ｏ     

Solubility of purified lutein diesters obtained from Tagetes erecta in supercritical CO(2) and the effect of solvent modifiers

Purified lutein diesters deposited on commercial nonporous glass beads were solubilized in supercritical CO(2) in a computerized batch extractor, and their solubilities were compared to their solubilities in hexane. Densities of 0.7, 0.8, and 0.9 g/mL were evaluated without modifiers. Both pressure and temperature increased solubility, although temperatures >50 degrees C promoted carotenoid loss as determined by mass balance. Solubility was enhanced by the use of modifiers and was related to their log P. Chloroform (log P = 2) increased 2.8 times the amount of solubilized lutein diesters compared to pure CO(2) at the same extraction conditions (0.9 g/mL and 40 degrees C) to yield 65% of the amount extracted with hexane. Supercritical CO(2) extraction of lutein diesters could represent a cleaner technology as compared to the current industrial use of hexane with important ecological and health-related implications.     

Volatile compounds in Spanish, French, and American oak woods after natural seasoning and toasting

The volatile composition (volatile phenols, phenolic aldehydes, furanic compounds, lactones, phenyl ketones, and other related compounds) of Spanish oak heartwood of Quercus robur, Quercus petraea,Quercus pyrenaica, and Quercus faginea was studied by gas chromatography/mass spectrometry, in relation to the processing in barrels cooperage and in relation to the French oak of Quercus robur (Limousin) and Quercus petraea (Allier) and American oak of Quercus alba (Missouri), which are habitually used in cooperage. The volatile composition of seasoned oak woods varied according to individual trees, species, and origins, and the differences were more significant in Spanish species with respect to American species than with respect to French species. The toasting process influenced the volatile composition of wood. It led to high increases in the concentration of volatile phenols, furanic aldehydes, phenyl ketones, and other related structures, but the effect on w-lactones levels depended on species and origin. The volatile composition in Spanish oak species evolved during toasting like in French and American oak, but quantitative differences were found, especially important in American species with respect to European species.     

Volatile compounds in a spanish red wine aged in barrels made of Spanish, French, and American oak wood

A red Rioja wine was aged in barrels made of Spanish oak wood (Quercus robur, Quercus petraea,Quercus pyrenaica, and Quercus faginea) during 21 months. The concentrations of some volatile compounds [syringaldehyde, vanillin, eugenol, maltol, guaiacol, 4-ethylphenol, cis and trans isomers of beta-methyl-gamma-octalactone, 2-furfuraldehyde, 5-methyl-2-furfuraldehyde, 5-(hydroxymethyl)-2-furfuraldehyde, and furfuryl alcohol] were studied in these wines and compared with those of the same wine aged in barrels made from French oak of Q. robur (Limousin, France) and Q. petraea (Allier, France) and American oak of Quercus alba (Missouri). Similar concentrations of these compounds were found in wines aged in Spanish and French oak wood barrels, and significantly different concentrations were found with respect to wines aged in barrels made of American oak wood, indicating a different behavior. Thus, wines with different characteristics were obtained, depending on the kind of wood. Also, the kind of wood had an important influence on sensory characteristics of wine during the aging process. Spanish oak wood from Q. robur, Q. petraea, and Q. pyrenaica can be considered to be suitable for barrel production for quality wines, because a wine aged in barrels made of these Spanish oak woods showed similar and intermediate characteristics to those of the same wine aged in French and American oak woods usually used in cooperage.     

PCR-SSCP: a simple method for the authentication of grouper (Epinephelus guaza), wreck fish (Polyprion americanus), and Nile perch (Lates niloticus) fillets

A method of DNA analysis has been developed to verify the authenticity of grouper (Epinephelus guaza), wreck fish (Polyprion americanus), and Nile perch (Lates niloticus) fillets. A short fragment (208 bp) of the mitochondrial 12S rRNA gene was amplified by the polymerase chain reaction and analyzed by single-strand conformation polymorphism to get species-specific patterns of single-stranded DNA (ssDNA). DNA strands were separated by native polyacrylamide gel electrophoresis and visualized by silver staining. Discrimination among the three fish species studied was possible, because each one expressed a specific ssDNA pattern.     

Supercritical fluid extraction of all-trans-lycopene from tomato

A procedure is proposed for the supercritical fluid extraction of all-trans-lycopene from tomato using carbon dioxide at 40 degrees C without modifier. The present method minimizes the risk of degradation via isomerization and oxidation of health-promoting ingredients, such as lycopene. The effect of different experimental variables on the solvating power of the supercritical fluid was evaluated in terms of both the selectivity achievable in the process and the yield of the extraction of all-trans-lycopene. Satisfactory separations of the all-trans-lycopene isomers from the cis counterparts were achieved using a C(30) column. The obtained extract contained 88% all-trans-lycopene and 12% cis-lycopene.     

1-甲基环丙烯延长菠菜采后保鲜期的研究

分别对经0.1、1.0μL.L-1浓度的1-甲基环丙烯(1-MCP)处理和未经1-MCP处理的离体菠菜叶片的衰老特性进行研究。结果表明,与对照相比,经1-MCP处理的菠菜叶片在避光、23℃条件下贮藏6 d后,叶绿素含量和光系统Ⅱ最高光量子产量较高,溶质渗漏量较低,说明1-MCP处理可延缓菠菜叶片的衰老。贮藏3 d后,经1-MCP处理的菠菜叶片乙烯生成量增加,随后又下降至对照水平。经1-MCP处理的菠菜叶片中具有较高的抗坏血酸和谷胱甘肽含量及对于这两种物质较低的氧化还原比率。1-MCP处理还可以减少菠菜叶片中的铵盐积累及蛋白质的降解。综合上述结果可以得出,通过1-MCP抑制菠菜叶片对乙烯作用的敏感性可有效延长菠菜的采后保鲜期。     

甲酸对肉仔鸡生产性能、消化率、肠组织形态和血浆代谢产物的影响

研究饲粮甲酸对肉仔鸡生产性能、消化率、肠组织形态和血浆代谢产物的影响。120只罗斯雄性肉仔鸡,在实验室饲养,饲养期为1～42日龄。试验设4个处理:对照组(C);添加阿维霉素,水平为10 mg·kg~(-1)(AV);添加甲酸,水平为5g·kg~(-1)(FA5)和添加甲酸,水平为10 g·kg~(-1) (FA10)。各处理间,雄性肉仔鸡的增重、饲料采食量或饲料转化率没有显著差异。42日龄时,育成鸡饲粮中,各种添加物对雄性肉仔鸡回肠干物质消化率有一定影响;与其他处理相比,阿维霉素和添加水平为10 g·kg~(-1)的甲酸,轻度增加回肠干物质消化率。添加水平为5 g·kg~(-1)和10g·kg~(-1)的甲酸对空肠pH没有影响,试验结果不能清楚显示甲酸对肠组织形态的积极作用。各处理间,血液代谢产物没有不同,血浆钙、磷水平不受甲酸添加物影响。结论:卫生状况良好的肉仔鸡,饲粮甲酸对生产性能、肠组织形态或血浆代谢产物水平没有清楚的积极的影响;然而,对回肠营养物质消化率有轻度积极的影响。     

The magnetic field of saturn: pioneer 11 observations

The intrinsic magnetic field of Saturn measured by the high-field fluxgate magnetometer is much weaker than expected. An analysis of preliminary data combined with the preliminary trajectory yield a model for the main planetary field which is a simple centered dipole of moment 0.20 +/- 0.01 gauss-Rs(3) = 4.3 +/- 0.2 x 10(28) gauss-cm(3) (1 Rs = 1 Saturn radius = 60,000 km). The polarity is opposite that of Earth, and, surprisingly, the tilt is small, within 2 degrees +/- 1 degrees of the rotation axis. The equatorial field intensity at the cloud tops is 0.2 gauss, and the polar intensity is 0.56 gauss. The unique moon Titan is expected to be located within the magnetosheath of Saturn or the interplanetary medium about 50 percent of the time because the average subsolar point distance to the magnetosphere is estimated to be 20 Rs, the orbital distance to Titan.