Optimization of protein extraction and solubilization for mature grape berry clusters

Protein extraction from grape berries has been challenging, particularly in mature berries, which can have sugar concentrations as high as 26%. Grape skins and seeds contain large amounts of polyphenols, which can also interfere with efficient protein extraction. In plants, two extraction protocols, TCA/acetone-based and phenol-based methods, have been mainly used to extract proteins from different organs or tissues on many species. However, few results have been reported for grape berry clusters. We wanted to determine which of these protocols was optimal for berry clusters in order to achieve both efficient protein extraction and high spot resolution on 2-D gels. Four protocols, derived from either TCA/acetone or phenol procedures, were tested on mature Cabernet Sauvignon whole berry clusters. The phenol-based protocols were superior to the TCA/acetone methods, showing larger protein yields and greater spot resolution on 2-D gels. One method was clearly superior to the rest, a phenol-based extraction method combined with resuspension in the presence of both urea and thiourea as chaotropes. A total of 81 spots were excised and identified following MALDI-TOF/TOF MS analyses. Their identification helped further characterize the specificity of each extraction procedure.     

Hypervalent iodine oxidation of phenol derivatives using a catalytic amount of 4-iodophenoxyacetic acid and Oxone as a co-oxidant

Reaction of p-substituted phenols 2 with a catalytic amount of 4-iodophenoxyacetic acid (1) and Oxone^® as a co-oxidant in tetrahydrofuran (THF) or 1,4-dioxane-water gave the corresponding p-quinols 3 in excellent yields. Reaction of p-dialkoxyarenes 4 in 2,2,2-trifluoroethanol-water gave the corresponding p-quinones 5 in excellent yield without purification. These reactions provide efficient and practical methods for the preparation of p-quinols and p-quinones from p-substituted phenols and p-dialkoxyarenes, respectively. This quinone synthesis was applied to synthesis of blattellaquinone (13), the sex pheromone of the German cockroach Blattella germanica.     

On the structure of penipratynolene and WA

The antipode of the structure proposed for the natural product penipratynolene in the literature was synthesized in high enantiopurity via an chiron approach and fully characterized. However, substantial differences were observed between the physical and spectroscopic data of the synthetic sample and those reported for the natural penipratynolene. Possible causes for the discrepancies are proposed on the basis of acquisition and comparison of additional data. The present work also provides the only piece of synthetic evidence for an antifungal natural product WA, the corresponding acid of the antipode of natural penipratynolene.     

疏水性二氧化硅气凝胶吸附水中微量苯酚和甲醛的研究

气凝胶是一种新型纳米多孔非晶材料,其密度低、比表面积大、孔隙率高,可以作为吸附剂.本文研究了稻壳灰为硅源制成的合甲基的疏水性二氧化硅气凝胶对水中微量苯酚和甲醛的吸附性能.结果表明,疏水性气凝胶对水中微量苯酚和甲醛具有一定的吸附能力,实验中对苯酚的吸附容量是1.93mg/g,要大于对甲醛的吸附容量0.92mg/g;增大气凝胶的疏水化程度可以增加其对水中微量苯酚和甲醛的平衡吸附容量;苯酚的吸附平衡等温曲线符合Langmuir和Freundlich方程,甲醛的吸附平衡等温曲线符合Freundlich方程.     

木质素对再造烟叶烟气中苯酚的影响

通过对木质素以及添加一定比例木质素的再造烟叶进行热裂解分析,探讨木质素对再造烟叶苯酚释放量的影响。结果表明,木质素热裂解产物中酚类物质含量较高;再造烟叶热裂解产生的苯酚及其他酚类物质含量随木质素含量的增加而升高。结果对降低再造烟叶及卷烟苯酚释放量的技术开发具有重要意义。     

膨润土负载掺铁氧化钛光降解苯酚

以钛酸四丁酯为原料,用溶胶-凝胶法制备了以膨润土为载体的负载型TiO2光催化剂;采用分光光度法测试其光降解性能;讨论了影响苯酚降解的主要因素。结果表明,在pH=8.0时,光催化剂的用量为15mg/L,苯酚溶液的浓度为5mg/L时,光照时间为120min,苯酚的降解率可达98.2%。