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以琯溪蜜柚柚皮为原料,采用纤维素酶辅助水蒸气蒸馏法提取精油,并对精油的抑菌活性进行了评价。在单因素实验的基础上,通过正交试验研究酶法提取柚皮精油的最佳工艺条件,并通过滤纸片法测定柚皮精油抑菌性活性的大小。结果表明,酶法辅助水蒸气蒸馏法优化后的提取工艺为:酶加量0.5%,提取温度45℃,pH=4.0,提取时间2 h,精油提取率为1.96%,相比优化前提高46%,相比水蒸气蒸馏法提高180%。提取的精油对酿酒酵母菌、枯草芽孢杆菌和藤黄微球菌均具有一定的抑制作用,对黑曲霉菌无抑制作用。 相似文献
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目的 优化滇刺枣多酚(Zizyphus mauritiana Lam. polyphenols, ZMP)超声辅助酶法提取工艺条件并测定ZMP抗氧化性。方法 以液料比、乙醇体积分数、超声温度、超声时间、超声功率、酶用量作为考察因素,在单因素实验考察基础上设计响应面法实验优化ZMP提取条件,并对ZMP清除DPPH自由基(DPPH·)、羟基自由基(·OH)的能力进行研究。结果 ZMP超声辅助酶法提取最佳工艺条件为:液料比为40∶1(m L∶g)、超声温度为41℃、超声功率为304W、酶用量为4.1%(m/m)、乙醇体积分数为60%、超声时间为50min,此时,ZMP提取量平均值为(18.41±0.16)mg·g-1,接近预测值(18.33mg·g-1)。抗氧化性测定结果显示,当ZMP质量浓度为3.0μg·m L-1时,对DPPH·、·OH的清除率分别为75%、72%,二者清除率均大于对照药品维生素C。结论 响应面法实验优化的ZMP超声辅助酶法提取工艺稳定、可行,具有较强的抗氧化性,ZMP可作为一种抗氧化剂开发利用。 相似文献
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目的优化广西莪术挥发油提取工艺,并分析挥发油的抗氧化活性。方法利用微波辅助提取法提取广西莪术挥发油,通过单因素和正交实验对提取工艺进行优化,再通过测定挥发油的还原性能力以及清除·OH、DPPH·能力,初步评价其抗氧化活性。结果微波辅助提取广西莪术挥发油的最佳提取工艺条件为料液比1∶20,提取时间6 min,提取功率900 W在最佳提取条件下提取率为5.18%。挥发油为100μg/m L时的还原性好于同浓度Vc,并且显示较好的清除羟基自由基和DPPH自由基能力,具有一定抗氧化效果。 相似文献
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以挥发油提取率为评价指标,采用单因素实验和响应面法实验优化陕产长春七挥发油的超声提取工艺,并考察了长春七挥发油对DPPH自由基和ABTS自由基的清除能力,评价其抗氧化活性。确定长春七挥发油的最佳提取工艺为:以乙醚为提取溶剂、料液比1∶53 (g∶mL)、超声时间20 min、超声温度26℃,在此工艺条件下,挥发油提取率为13.639 2%,与理论值相差0.002 4%,说明此方法可行。长春七挥发油对DPPH自由基和ABTS自由基均有较高的清除率,且随着浓度增大清除能力增强,长春七挥发油清除DPPH自由基线性范围在1.4~1.8 mg·mL~(-1)为最佳,长春七挥发油清除ABTS自由基线性范围在2.5~3.5 mg·mL~(-1)为最佳。为进一步有效开发利用陕西"太白七药"提供了一定的理论基础。 相似文献
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以艾叶挥发油提取率为考核指标,采用单因素实验考察浸泡时间、料液比、提取时间等对艾叶挥发油提取率的影响,在此基础上,采用响应面法优化艾叶挥发油的共水蒸馏提取工艺,并通过紫外分光光度法测定艾叶挥发油对DPPH自由基的清除率来评价其抗氧化性能。结果表明,艾叶挥发油的最佳提取工艺条件为:浸泡时间1.5 h、料液比1∶10(g∶mL)、提取时间4.5 h,在此条件下,艾叶挥发油提取率最高,为0.83%。当艾叶挥发油浓度为80 mg·mL~(-1)时,DPPH自由基清除率最高,为39.12%。表明艾叶挥发油具有一定的抗氧化活性。 相似文献
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Raheleh Ghanbari Mohammad Zarei Afshin Ebrahimpour Azizah Abdul-Hamid Amin Ismail Nazamid Saari 《International journal of molecular sciences》2015,16(12):28870-28885
In recent years, food protein-derived hydrolysates have received considerable attention because of their numerous health benefits. Amongst the hydrolysates, those with anti-hypertensive and anti-oxidative activities are receiving special attention as both activities can play significant roles in preventing cardiovascular diseases. The present study investigated the angiotensin-I converting enzyme (ACE) inhibitory and anti-oxidative activities of Actinopyga lecanora (A. lecanora) hydrolysates, which had been prepared by alcalase, papain, bromelain, flavourzyme, pepsin, and trypsin under their optimum conditions. The alcalase hydrolysate showed the highest ACE inhibitory activity (69.8%) after 8 h of hydrolysis while the highest anti-oxidative activities measured by 2,2-diphenyl 1-1-picrylhydrazyl radical scavenging (DPPH) (56.00%) and ferrous ion-chelating (FIC) (59.00%) methods were exhibited after 24 h and 8 h of hydrolysis, respectively. The ACE-inhibitory and anti-oxidative activities displayed dose-dependent trends, and increased with increasing protein hydrolysate concentrations. Moreover, strong positive correlations between angiotensin-I converting enzyme (ACE) inhibitory and anti-oxidative activities were also observed. This study indicates that A. lecanora hydrolysate can be exploited as a source of functional food owing to its anti-oxidant as well as anti-hypertension functions. 相似文献
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Salleh WM Ahmad F Yen KH Sirat HM 《International journal of molecular sciences》2011,12(11):7720-7731
Chemical composition, antioxidant and antimicrobial activities of the fresh leaves and stems oils of Piper caninum were investigated. A total of forty eight constituents were identified in the leaves (77.9%) and stems (87.0%) oil which were characterized by high proportions of phenylpropanoid, safrole with 17.1% for leaves and 25.5% for stems oil. Antioxidant activities were evaluated by using β-carotene/linoleic acid bleaching, DPPH radical scavenging and total phenolic content. Stems oil showed the highest inhibitory activity towards lipid peroxidation (114.9 ± 0.9%), compared to BHT (95.5 ± 0.5%), while leaves oil showed significant total phenolic content (27.4 ± 0.5 mg GA/g) equivalent to gallic acid. However, the essential oils showed weak activity towards DPPH free-radical scavenging. Evaluation of antimicrobial activity revealed that both oils exhibited strong activity against all bacteria strains with MIC values in the range 62.5 to 250 μg/mL, but weak activity against fungal strains. These findings suggest that the essential oils can be used as antioxidant and antimicrobial agents for therapeutic, nutraceutical industries and food manufactures. 相似文献
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采用超临界二氧化碳萃取法提取深山含笑和乐昌含笑叶片挥发油,应用GC-MS技术测定挥发油的成分并对其DPPH自由基清除能力和还原能力等抗氧化指标进行测定.结果表明:深山含笑萜类为35.35%,酯类为15.12%,醇类为9.09%,其余37.02%为萜烯类含氧衍生物.乐昌含笑萜类为28.49%,酯类为11.12%,醇类为1.94%,其余54.55%为萜烯类含氧衍生物.两种含笑叶片挥发油质量浓度为50mg/L时DPPH自由基清除能力达到饱和,且挥发油质量浓度越大还原能力越强.通过与常用抗氧化剂进行比较,发现两种含笑叶片挥发油的抗氧化能力均强于植酸PA、没食子酸丙酯PG和抗坏血酸Vc. 相似文献
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Janina Dose Seiichi Matsugo Haruka Yokokawa Yutaro Koshida Shigetoshi Okazaki Ulrike Seidel Manfred Eggersdorfer Gerald Rimbach Tuba Esatbeyoglu 《International journal of molecular sciences》2016,17(1)
Astaxanthin is a coloring agent which is used as a feed additive in aquaculture nutrition. Recently, potential health benefits of astaxanthin have been discussed which may be partly related to its free radical scavenging and antioxidant properties. Our electron spin resonance (ESR) and spin trapping data suggest that synthetic astaxanthin is a potent free radical scavenger in terms of diphenylpicryl-hydrazyl (DPPH) and galvinoxyl free radicals. Furthermore, astaxanthin dose-dependently quenched singlet oxygen as determined by photon counting. In addition to free radical scavenging and singlet oxygen quenching properties, astaxanthin induced the antioxidant enzyme paroxoanase-1, enhanced glutathione concentrations and prevented lipid peroxidation in cultured hepatocytes. Present results suggest that, beyond its coloring properties, synthetic astaxanthin exhibits free radical scavenging, singlet oxygen quenching, and antioxidant activities which could probably positively affect animal and human health. 相似文献
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深山含笑和乐昌含笑叶片挥发油的成分分析及性能测定 总被引:1,自引:0,他引:1
采用超临界二氧化碳萃取法提取深山含笑和乐昌含笑叶片挥发油,应用GC-MS技术测定挥发油的成分并对其DPPH自由基清除能力和还原能力等抗氧化指标进行测定。结果表明:深山含笑萜类为 35.35%,酯类为 15.12%,醇类为 9.09%,其余 37.02% 为萜烯类含氧衍生物。乐昌含笑萜类为 28.49%,酯类为 11.12%,醇类为 1.94%,其余 54.55%为萜烯类含氧衍生物。两种含笑叶片挥发油质量浓度为 50 mg/L 时DPPH自由基清除能力达到饱和,且挥发油质量浓度越大还原能力越强。通过与常用抗氧化剂进行比较,发现两种含笑叶片挥发油的抗氧化能力均强于植酸 PA、没食子酸丙酯 PG 和抗坏血酸 Vc。 相似文献
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采用水水蒸馏-乙醚萃取法手和Clevenger法萃取草果挥发性成分.分别以1.12%和1.87%的平均得率获得了精油。用GC/MS分析方法从水蒸气景馏-乙醚革取扶得的精油中检测出30种成分.解析鉴定出其中29个成分,总相对含量占精油全部组分的99.619%,主要成分为1,8-桉树脑(41.4.33%)、α-水芹烯(7.882%)、2-异丙基苯甲醛(5.930%)。Cleverlger法所得精油榆测出38种成分.解析鉴定出其中32个成分,总相对含量占精油全部组分的98.395%,主要成分为1.8-桉树脑(40.891%)、α-水芹烯(9.769%)2-异丙基苯甲醛(6.988%)。两种方法获得的精油郁具有明显的清除DPPH自由基能力,在浓度为为10mg/mL。时,以水蒸气蒸馏-乙醚萃取法和Clevenger法所获得的精油对DPPH的清除率分别为80.0%和75.8%。 相似文献
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Ivana Tomaz Luna Maslov Domagoj Stupić Darko Preiner Danijela Ašperger Jasminka Karoglan Kontić 《分离科学与技术》2016,51(2):255-268
Grape skin contains large amounts of different flavonoids so it can be used for their recovery. Optimization of enzyme-assisted extraction of flavonoids was conducted using oenological enzyme preparations with respect to enzyme dosage, temperature, extraction time, pH, and enzyme preparation. Optimal conditions were obtained using enzyme preparation Lallzyme EX-V, at the temperature of 45°C, time of 3 h, pH 2.0, and enzyme dosage of 10.52 mg/g. The new optimized extraction method is less expensive, simple, accurate, and selective for the recovery of simple flavonoids. It is based on an environmentally-friendly extraction solvent which may provide a valuable alternative to conventional methods. 相似文献
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为明晰采收后向日葵盘精油的成分及其体外抗氧化活性,应用水蒸气蒸馏法提取采收后向日葵盘精油,利用气相色谱-质谱联用法(GC-MS)分析其化学成分,通过DPPH自由基和ABTS自由基清除法对精油的体外抗氧化活性进行测定。结果显示:从向日葵盘精油中共鉴定出49种化学成分(占精油总量91.16%),其中α-蒎烯(28.22%)、柠檬烯(6.55%)、α-蛇麻烯(4.99%)、反式-β-金合欢烯(3.58%)和莰烯(3.39%)为其主要成分。向日葵盘精油具有一定的体外抗氧化活性,其清除DPPH自由基、ABTS自由基的半数有效浓度(EC50)值分别为0.47、0.30 g/L,明显高于阳性对照BHT的EC50值(分别为8.21和6.16 mg/L)。 相似文献