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91.
Reactive oxygen species (ROS) at physiological concentrations may be required for normal cell function. Excessive production of ROS can be detrimental to cells, because ROS can cause oxidative damage to lipids, proteins, and DNA. Herein, we describe the isolation and purification of a novel antioxidant protein the water extract of dried, powdered Sundakai (Solanum torvum [Solanaceae]) seeds. Sundakai belongs to the Solanaceae family, a small shrub, which is distributed widely in India, Malaya, China, Phillipines and tropical America. Fifty percent of ammonium sulphate-precipitated crude water extract was fractionated on a Sephadex G100 column, which yielded two peaks, PI and PII. Peaks PI and PII inhibited lipid peroxidation up to 40% and 89%, respectively in linolenic acid micelles. Rechromatographing of peak PII on Sephadex G100 yielded a single peak, indicating the homogeneity of the purified protein. SDS–PAGE analysis indicated the molecular weight of the purified protein to be ∼28 kDa. The purified protein, at 0.8 μM, inhibited deoxyribose degradation induced by generation of hydroxyl radicals by 90% and scavenged DPPH (1,1-diphenyl-2-picrylhydrazyl) radicals by 76%. The reducing power and chelating power of the purified protein, at 0.8 μM, were found to be 72% and 85%, respectively. The protein, at 0.8 μM, also offered significant protection to calf thymus DNA damage induced by H2O2 (1 mM). Therefore, the present study demonstrates, for the first time, a novel protein from the water extract of Sundakai seeds as an excellent antioxidant. 相似文献
92.
Pollination trials in otherwise male-free hop gardens are described. The results showed that a reduction in cone yield of up to 30% may be expected from seedless hops, but an increase in α-acid content of the cones more or less compensates for this yield reduction and the yield of α-acid per acre can be almost as high from seedless as seeded hops. Northern Brewer, in particular, performed better than other varieties when grown seedless but most of the high α-acid varieties gave reasonable results. It is suggested that the variation in response may depend on the number of resin glands present on the seeds of the different varieties, and differences in the distribution of resin glands on other parts of the cone. 相似文献
93.
94.
K.S. Triantafyllidis A.A. Lappas I.A. Vasalos Y. Liu H. Wang T.J. Pinnavaia 《Catalysis Today》2006,112(1-4):33-36
Aluminosilicate mesostructures (MSU-SBEA) assembled from zeolite Beta (BEA) seeds exhibited relatively high hydrothermal stability and were significantly more active in the cracking of gas–oil compared to MCM-41 after severe steaming pretreatment. The MSU-SBEA mesoporous materials with wormhole framework structure and those having morphology of solid nanoparticles with high interparticle mesoporosity were more steam-stable and more active after severe steaming than those with hexagonal pore structure. Differences in acid sites strength between the MSU-SBEA materials and MCM-41 could not be probed by the complex reaction system of the large hydrocarbon molecules of gas–oil. 相似文献
95.
M. A. S. Barrozo C. A. S. Felipe D. J. M. Sartori J. T. Freire 《Drying Technology》2006,24(4):415-422
The present work describes and analyzes Brazilian research related to the quality of soybean seeds dried in moving bed dryers. The main process variables were drying air temperature, relative humidity and velocity, and solid flow rate. The statistical methodology used allowed the achievement of empirical equations for predicting the quality of soybean seeds (germination, vigor, and fissures) in two classical configurations of the moving bed: countercurrent and crosscurrent. The results show that the increase of the seed coat cracking is associated to conditions that lead to a high drying rate. Germination and vigor reduction is also associated to the overdrying conditions. 相似文献
96.
F. Szöcs 《Journal of food science》2002,67(6):2079-2082
ABSTRACT: We used electron spin resonance (ESR) to investigate free radicals in wheat seeds in air or under vacuum in relation to annealing temperature. Annealing in the 100 to 200 °C range resulted in concentration increases of free radicals in samples. A greater increase was observed for experiments carried out in air than for those under vacuum. Most free radicals occurred in the grain surface layer. The bran contained a concentration of free radicals 100 times greater than that of the white grain portion. The reaction of stable free radicals in bran was also studied during thermal decomposition of dibenzoyl peroxide at high pressure. They reacted with shortlived peroxyl radicals in bran to produce a nonradical product. 相似文献
97.
Seham Fiad 《Journal of the American Oil Chemists' Society》1991,68(1):23-25
The component triacylglycerols of six seed oils of the Malvaceae family—Gossypium barbadense (Egyptian cotton),Hibiscus cannabinus (kenaf),Hibiscus sabdarifa (roselle), two varieties ofHibiscus esculentas (okra) andAlthea rosea (ketmia, hollyhock or Egyptian hemp)—have been determined by using the lipase hydrolysis technique. The oils were found to
contain triacylglycerols belonging to trisaturated (1.0–2.1), disaturated-monounsaturated (12.3–20.9), monosaturated-diunsaturated
(42.3–46.6) and triunsaturated (30.1–44.2) types of triacylglycerols. 相似文献
98.
通过引入凝胶和晶体介质对液相扩散速率的修正因子,在非自成核体系得到修正的Lechert分子筛晶体生长动力学模型,给出了诱导期和晶体快速生长期的计算公式,表明了晶种量对诱导期影响的特殊性。与Lechert模型相比,该模型不仅对Y型、ZSM-5型和L型实验晶化曲线的前期和后期进行了较好的拟合,且可通过Y型分子筛晶体生长曲线定性推断导向剂中初始晶种的半径、晶种量和颗粒密度随导向剂老化条件的变化规律。 相似文献
99.
100.
Disinfection of Rice Seeds Prior to Sprouting 总被引:3,自引:0,他引:3
Different methods of rice seeds disinfection were investigated in order to limit the development of micro-organisms during sprouting. At room temperature, sodium hypochlorite at 1000 ppm or hydrogen peroxide resulted in a 2 to 3 log decrease in aerobic plate counts. Ethanol was found to inhibit germination, thus prohibiting its use. The limited effectiveness of decontaminating solutions could be because they did not access the bacteria, which was supported by the results of washing with benzalkonium chloride. Greater reduction (up to 5 log) was obtained by soaking seeds for 5 min in a sodium hypochlorite solution at 60°C. 相似文献