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11.
Bo Yu Zhao-Xin Lu Xiao-Mei Bie Feng-Xia Lu Xian-Qing Huang 《European Food Research and Technology》2008,226(3):415-421
Many bioactive peptides possess specific biological properties that make these potential ingredients of health-promoting foods.
Increasing attention is being focused on physiologically active peptides derived from soybean proteins. In this study, soybean
peptides were produced by fermentation of defatted soybean meal with Bacillus subtilis SHZ and purified by ultrafiltration and gel chromatogram. Free radical scavenging property and the effect on anti-fatigue
of the peptides were evaluated in vitro and in vivo, respectively. Swimming endurance tests of mice were carried out after
20 days of soybean peptides administration (0, 100, 200, 400 mg/kg BW/day for control, low-dose, middle-dose and high-dose
group, respectively). And the blood lactate and hepatic glycogen of mice were determined. Results showed that the purified
peptides exhibited significant (P < 0.01) scavenging potencies on superoxide (62%) and hydroxyl (96%) at a concentration of 10 mg/ml. The average swimming
time of the low-, middle- and high-dose group was increased by 20.91, 45.45 and 70% compared with that of control group, respectively.
And administration with soybean peptides could significantly accelerate the clearance of blood lactate after mice swimming
(P < 0.01). The hepatic glycogen storage of middle and high dose groups were obviously increased (P < 0.05). It suggested that the soybean peptides produced by fermentation could significantly alleviate physical fatigue of
the mice. 相似文献
12.
The process of ozonation of glyoxal in aqueous solution has been studied by following its chemical and kinetic evolution. Results show that the oxidative process leads to formation of carboxylic functions and carbon dioxide according to a constant selectivity ratio at varying conversion degree.. Comparison between the oxygen amounts of reaction products and the corresponding ozone consumptions reveals that molecular oxygen takes part in the reaction process. System behavior is explained on the basis of radical reaction mechanism. 相似文献
13.
采用DPPH·、O2^-、和HO·的清除试验及卵磷脂脂质体氧化试验,研究比较了沙棘籽原花色素和葡萄籽原花青素的抗氧化活性。结果表明:两种原花色素对DPPH·、O2^-·和HO·均具有较强的清除能力;沙棘籽原花色素对O2^-的清除速率和清除活力及对HO·的清除活力显著高于葡萄籽原花青素,对O2^-的半清除浓度分别为23.95μg/mL,与HO·反应的速率常数分别为1.355×10^9L/g·s。两种原花色素均可显著延长AAPH诱导的卵磷脂脂质体氧化的延迟期时间、降低延迟期和扩增期氧化速率,沙棘籽原花色素抑制氧化的效果强于葡萄籽原花青素。 相似文献
14.
The purpose of this study was to determine the reducing power, metal chelating, and radical scavenging capabilities of water and ethanol extracts of sumac (Rhus coriaria L.), comparatively. The water and ethanol extracts of sumac were evaluated for their radical scavenging activities by means of the DPPH and DMPD assays. Water extract of sumac (R. coriaria L.) scavenged radicals effectively with EC50 values of 36.4 ??g/ml for DPPH free radical and 44.7 ??g/ml for DMPD cation radical. Similarly, the total reducing power of water extract was found higher than ethanol extract in both potassium ferricyanide reduction (FRAP) and cupric ions reduction capacity methods (CUPRAC). 2,2′-Bipyridine was used to determine the metal chelating activity and the result of water extract was found higher than ethanol extract. Total phenolic and total flavonoid contents of both extracts were studied as well. The values of water extract were found to be higher than that of ethanol extract. The present study found that water extracts of sumac (R. coriaria L.) have effective antioxidant and radical scavenging activities as compared to ethanol extracts. 相似文献
15.
In addition to nine known bromophenol derivatives, five new nitrogen-containing bromophenols were isolated from an ethyl acetate extract of the marine red alga Rhodomela confervoides. By using spectroscopic methods, the structures of the new compounds were identified as 3-(2,3-dibromo-4,5-dihydroxybenzyl)pyrrolidine-2,5-dione (1), methyl 4-(2,3-dibromo-4,5-dihydroxybenzylamino)-4-oxobutanoate (2), 4-(2,3-dibromo-4,5-dihydroxybenzylamino)-4-oxobutanoic acid (3), 3-bromo-5-hydroxy-4-methoxybenzamide (4), and 2-(3-bromo-5-hydroxy-4-methoxyphenyl)acetamide (5). All of these bromophenols showed potent scavenging activity against DPPH (1,1-diphenyl-2-picrylhydrazyl) radicals, with IC(50) values ranging from 5.22 to 23.60μM. These compounds also displayed moderate activity against ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonate) radicals, with Trolox Equivalent Antioxidant Capacity values (TEAC) ranging from 2.11 to 3.58mM. The results obtained in this study demonstrate that the bromophenols obtained from R. confervoides may have potential application in food and/or pharmaceutical fields as natural antioxidants. 相似文献
16.
介绍了采用二步硅烷交联工艺制备高交联度易加工硅烷交联管材专用料的方法,讨论了基础树脂、助剂对专用料交联度和加工性能的影响;通过加入自由基捕捉剂的方法,抑制接枝反应过程中的碳-碳大分子交联,解决了二步法硅烷交联领域的技术瓶颈问题,使硅烷交联管材专用料既具有高的交联度又具有良好的加工性能. 相似文献
17.
Francisco López-Carrasquero Giuseppe Giammanco Angélica Díaz Johanna Dávila Carlos Torres Estrella Laredo 《Polymer Bulletin》2009,63(1):69-78
A series of comb like poly(p-n-alkylstyrene)s with linear alkyl groups, containing even numbers of carbon atoms from 12 up to 22 were synthesized by radical
polymerization and characterized by FTIR, 1H NMR, TGA, TVA DSC, and WAXS. All polymers were obtained in good yields and were soluble in organic solvents as chloroform,
dichloromethane or tetrahydrofuran and insoluble in methanol; they are stable up to temperatures near 300 °C. On the other
hand, the alkylic side chains of all series are able to crystallize in a paraffinic phase in which the melting temperature
and enthalpy increase with the methylene number of the n-alkyl chain. 相似文献
18.
Sea urchin gonads are highly priced sushi foodstuff “Uni” in Japanese traditional food, but after removal of them the residual shells with spines are dumped as waste. However, sea urchin shells contain naphthoquinone pigments with several phenolic hydroxyl groups, which were expected to act as potent antioxidant substances by donating hydrogens. Our previous study has evaluated their antioxidant ability to depress lipid peroxidation. This study examined other antioxidant property of the pigments from purple sea urchin shells, which possess larger amount of pigments than those of red and green sea urchins. The pigments as well as known antioxidant, α-tocopherol, exhibited 1,1-diphenyl 2-picryhydrazyl (DPPH) radical scavenging ability. Superoxide anion radical and hydrogen peroxide were also scavenged while hydroxyl radical, one of the most reactive oxygen species, was not significantly inhibited. However, because the pigments had significant activity to scavenge hydrogen peroxide and superoxide anion radical that could be in vivo precursors of hydroxyl radical, sea urchin pigments would be able to depress the generation of its related active oxygen radical species. These results suggested that sea urchin shells, which are still regarded as food waste, would be a new bio-resource for obtaining natural antioxidant. 相似文献
19.
BDC引发苯乙烯的均相聚合反应是以活性自由基机理进行的;大分子自由基间的偶合反应及向大分子的链转移反应使聚合产物不带有活性端基;大分子链活性端基数的测定结果表明了这种失活性的存在。 相似文献
20.
本文采用大分子单体法合成了结构明确的两亲接枝共聚物—聚苯乙烯接枝聚氧乙烯 ( PS— g—PEO) ,通过 IR,NMR和 GPC系统表征了两亲接枝共聚物。通过定性和定量的表征研究 ,结果证明两亲接枝共聚物 PS— g— PEO具有预期的结构 相似文献