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101.
目的 研究不同浓度甜菜碱与褪黑素复合处理对采后龙眼果实冷藏的保鲜效果,以期为龙眼贮藏保鲜新技术提供理论参考。方法 以‘储良’龙眼为实验材料,分别采用0、5、10、15 mmol/L的甜菜碱与300 mmol/L的褪黑素复配制成保鲜剂处理果实。在温度为4 ℃、相对湿度为85%条件下贮藏,研究其冷藏期间质量损失率及可溶性固形物(TSS)、可滴定酸(TA)、抗坏血酸(VC)、丙二醛(MDA)、游离脯氨酸含量和过氧化氢酶(CAT)、过氧化物酶(POD)、超氧化物歧化酶(SOD)活性的变化。结果 与300 mmol/L褪黑素对照组相比,复合保鲜剂能有效减少龙眼果实水分、TSS、TA、VC和游离脯氨酸含量的损失,使龙眼果肉保持较高的SOD、CAT活性(P<0.05),而POD活性和MDA含量维持在较低水平。结论 300 mmol/L褪黑素+10 mmol/L甜菜碱处理对龙眼的冷藏保鲜效果最佳。 相似文献
102.
该研究以混合菌种雪莲菌为发酵菌种,枸杞原浆中甜菜碱含量为指标,通过单因素试验和正交试验对雪莲菌发酵枸杞原浆进行工艺优化,并对发酵后的枸杞原浆进行品质分析。结果表明,最佳发酵工艺条件为雪莲菌接种量5%(m/V),发酵时间48 h,发酵温度25 ℃,此条件下甜菜碱含量为18.95 mg/mL,比未发酵枸杞原浆甜菜碱含量增加2.54倍,总酚含量为2.03 mg/mL、黄酮含量为0.68 mg/mL、总糖含量为11.92 mg/mL。雪莲菌发酵后枸杞原浆中共检测出65种挥发性成分,包括21种醇类、27种酯类、1种醛类、1种酮类、8种酸类、3种烷类、2种酚类和2种烯类,与发酵前相比新增24种,且醇类、酯类和酸类物质较发酵前显著性增加,挥发性成分总含量由8.94 mg/mL增加至39.76 mg/mL,为制备高品质枸杞原浆提供理论依据,为枸杞产业化深加工提供指导。 相似文献
103.
新型甜菜碱两性表面活性剂的合成 总被引:1,自引:0,他引:1
本文以脂肪醇缩水甘油醚(I)为原料,经开环和羧甲基化两步反应合成了三种含有羟丙基的甜菜碱型两性表面活性剂(Ⅱ)。 相似文献
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The alterations caused by betaine-type zwitterionic and anionic surfactant mixed systems in the permeability of unilamellar
liposomes have been investigated. The partition coefficient of these systems, at different molar fractions, between the aqueous
phase and the lipid bilayer of liposomes has been determined. These surfactant mixed systems were formed byN-dodecyl-N,N-dimethylbetaine (C12-Bet) and sodium dodecyl sulfate (SDS) in the presence of 20 mM PIPES buffer and 110 mM Na2SO4, at pH 7.21. Unilamellar liposomes were prepared from egg phosphatidylcholine and phosphatidic acid (9:1 molar ratio). The
release of the fluorescent agent 5-(6)-carboxyfluorescein induced by the systems has been studied at sub-solubilizing concentrations.
When the molar fraction of C12-Bet/SDS is about 0.4, the critical micelle concentration values of these systems exhibit a minimum, whereas their partition
coefficient between the aqueous phase and lipid bilayer of lipid bilayers shows a maximum. There is a consistent correlation
between the partition coefficient and the ability of the different systems of surfactants to modify the permeability of liposomes. 相似文献
107.
Xinrui Wang Xiaoqin Shang Peng Liu Fengwei Xie Tingyu Xiao Shanshan Song Zhe Gong 《Journal of surfactants and detergents》2018,21(5):647-655
In this work, the reaction kinetics of betaine synthesis were investigated. Specifically, an integral method was used to analyze the experimental data of the amidation reaction over the temperature range of 413.15–453.15 K and the data of the quaternization reaction over the temperature range of 348.15–368.15 K. The 2 reaction steps were shown to match the second‐order bimolecular kinetics model, and their equations could be deduced from the experimental data at different temperatures. The activation energy, Ea, and the pre‐exponential factor, A, were obtained from the equilibrium constant at different temperatures using the Arrhenius equation. For the 2 reactions, the activation energies were 31.68 and 47.03 kJ mol?1, respectively, and the preexponential factors were 26.99 and 4.07 × 104. Over the tested temperature range, the kinetic model equations were verified by comparing the additional experimental data with the theoretical values. This study provides a theoretical basis for the continuous production of palmitamidopropyl betaine. 相似文献
108.
109.
粘弹性表面活性剂胶束酸在砂岩储层分流酸化中的应用 总被引:3,自引:0,他引:3
粘弹性表面活性剂(VES)技术已在碳酸盐岩油气藏压裂、酸化中得到成功的应用,同样VES技术可应用于砂岩酸化。实验合成出新型粘弹性表面活性剂-芥子酰胺丙基甜菜碱(SAP-BET),由于SAP-BET为具有很长疏水碳链的两性粘弹性表面活性剂,所以用其配制的胶束流体具有良好的粘弹性行为,可用其配制具有自主分流、控滤失等特性的酸液或清洁压裂液。根据粘性表皮系数,建立了砂岩VES胶束流体分流酸化技术。该酸化工艺适合高温非均质多层砂岩油藏分流酸化。 相似文献
110.
The wastewater from baker's yeast production contains above‐average concentrations of organic pollutants (25 000 mg/L total chemical oxygen demand, TCOD), nutrients (1500 mg/L Ntot, 100 mg/L Ptot) and sulphate (2900 mg/L SO42?). Baker's yeast wastewater with a flow rate of 190 m3/day was treated in a mesophilic anaerobic/anoxic continuous stirred tank reactor (CSTR) system. At the expense of the reduction of trimethylglycine (or betaine‐component of sugar‐beet molasses) to other nitrogen‐containing compounds, it was possible to re‐oxidize the sulphides to elemental sulphur, remove them from the wastewater and increase biogas production. Therefore, the average removal efficiency in the anaerobic/anoxic system was 79% by TCOD, 100% by SO42? in which the concentration of sulphides in the effluent did not exceed 50 mg/L. The application of this combined anaerobic/anoxic system to a full‐scale treatment plant supported biogas production up to 1300 m3/day, and the purification of wastewater was feasible without the use of granular sludge. 相似文献