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1.
响应面法优化紫山药花青苷提取工艺 总被引:1,自引:0,他引:1
以紫山药为实验材料,以酸性乙醇为提取溶剂通过Box-Behnken响应面法及Design-Expert 8.0.6分析软件建立二次多项式数学模型优化紫山药花青苷的提取工艺及参数。研究表明,五种单因素对花青苷得率影响大小的顺序为X5(盐酸质量分数)X2(时间)X4(乙醇体积分数)X3(料液比)X1(温度)。并且温度和料液比、温度和乙醇体积分数、提取时间和料液比、提取时间和盐酸体积分数之间存在交互作用。得到紫山药花青苷最佳提取工艺参数为温度:81℃、时间:3.5 h、料液比:1∶25、乙醇体积分数:70%、盐酸质量分数:18‰。在此条件下花青苷平均得率达到4.928 mg/g,相对标准偏差为0.31%,与数学模型理论得率间的相对误差小于1.0%。 相似文献
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以紫山药为实验材料,以酸性乙醇为提取溶剂通过Box-Behnken响应面法及Design-Expert 8.0.6分析软件建立二次多项式数学模型优化紫山药花青苷的提取工艺及参数。研究表明,五种单因素对花青苷得率影响大小的顺序为X5(盐酸质量分数)>X2(时间)>X4(乙醇体积分数)>X3(料液比)>X1(温度)。并且温度和料液比、温度和乙醇体积分数、提取时间和料液比、提取时间和盐酸体积分数之间存在交互作用。得到紫山药花青苷最佳提取工艺参数为温度:81℃、时间:3.5 h、料液比:1∶25、乙醇体积分数:70%、盐酸质量分数:18‰。在此条件下花青苷平均得率达到4.928 mg/g,相对标准偏差为0.31%,与数学模型理论得率间的相对误差小于1.0%。 相似文献
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《中国野生植物资源》2020,(2)
目的:以贵州罗甸野生多穗柯为原料,研究超声波辅助法对多穗柯根皮苷提取率的影响。方法:在单因素试验基础上采用正交试验研究提取时间、提取温度、料液比、超声波功率对根皮苷得率的影响。结果:较佳提取工艺条件为提取时间50 min、提取温度50℃、提取功率720 W、料液比1∶30,此提取工艺提取率为1386%,RSD为0726%。结论:该工艺稳定性好、重复性高,是一种高效提根皮苷的方法。 相似文献
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紫色小白菜有机酸的提取优化及UPLC定量分析 总被引:1,自引:0,他引:1
为建立一种紫色小白菜中精准的有机酸提取及定性定量分析方法。本研究在单因素试验的基础上,采用Box-Behnken的中心组合试验设计原理,设计响应面试验优化紫色小白菜有机酸的提取工艺。结果表明,紫色小白菜有机酸提取的最优工艺参数为:乙醇浓度73%,料液比1∶21,超声时间11 min,超声温度70℃。通过超高效液相色谱法(ultra performance liquid chromatography,UPLC)对紫色小白菜叶片和叶柄部位有机酸进行定性定量分析,检测出苹果酸、柠檬酸、丙二酸、琥珀酸和酒石酸,其中苹果酸含量最高,分别为15.968、5.019 mg/g;其次为柠檬酸,分别为9.293、1.385 mg/g。定性定量结果表明,紫色小白菜叶片及叶柄部位含有丰富有机酸类物质,叶片部位苹果酸、柠檬酸、丙二酸、酒石酸含量均高于叶柄部位,而琥珀酸含量较低。 相似文献
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采用超声波法提取北五味子果实中的果胶成份,咔唑-浓硫酸显色法测果胶得率,并应用正交试验设计对其提取工艺参数进行了优化。试验结果表明:各因素对北五味子果胶提取的影响顺序依次为超声功率提取温度料液比提取时间,最佳工艺参数为超声功率200 W,提取温度为65℃,料液比为1∶30,提取时间为50 min,果胶提取率为6.32%。 相似文献
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为了筛选超声提取中国楤木根皮粗多糖的工艺,以中国楤木根皮多糖得率为衡量指标,采用水提醇沉法,对中国楤木根皮粗多糖超声提取工艺中提取时间、提取温度、超声功率、料液比4个因素用正交设计法进行优化研究。结果表明:中国楤木根皮粗多糖超声提取最佳工艺为温度70℃,料液比1∶30(g/m L),提取时间80 min,超声功率100 W,此工艺下多糖得率为11.13%。该方法提取的多糖测得稳定性、重现性均良好。所得到的优化提取工艺准确可靠,保证了中国楤木根皮多糖的有效提取。 相似文献
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通过单因素实验和正交实验,研究料液比、超声功率、超声提取温度和超声作用时间对王不留行多糖提取效果的影响。分别采用紫外分光光度法和邻苯三酚自氧化法测定其清除DPPH·和O-·2的作用进行试验,根据试验结果评价其体外抗氧化活性。得出优化工艺条件为:料液比(g∶m L)1∶50,提取温度60℃,超声功率100W,作用时间40 min。王不留行多糖的得率为9.60%,优选王不留行多糖的超声提取工艺,省时、高效、可靠、重现性好;体外抗氧化性试验显示王不留行多糖对DPPH·和O-·2具有较强的清除能力,且在一定范围内其抗氧化作用与浓度呈现良好的量效关系。 相似文献
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采用超声波法提取北五味子果实中的果胶成份,咔唑-浓硫酸显色法测果胶得率,并应用正交试验设计对其提取工艺参数进行了优化。试验结果表明:各因素对北五味子果胶提取的影响顺序依次为超声功率>提取温度>料液比>提取时间,最佳工艺参数为超声功率200 W,提取温度为65℃,料液比为1∶30,提取时间为50 min,果胶提取率为6.32%。 相似文献
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正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases 相似文献
12.
Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme
responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare
the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show
that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by
distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of
demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least
one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of
the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable
potent antiproliferative synthetic drugs. 相似文献
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The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle. 相似文献
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Meng Miao Gang Deng Xiaobei Xiong Yang Qiu Wenda Huang Meng Yuan Fei Yu Shimei Bai Xi Zhou Xiaolu Zhao 《中国病毒学》2022,37(2):314-317
Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions. 相似文献
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions. 相似文献
16.
Dong Liu Xin Wang Yisong Wang Peigang Wang Dongying Fan Sichang Chen Yuguang Guan Tianfu Li Jing An Guoming Luan 《中国病毒学》2018,33(5):402-409
Rasmussen’s encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8+ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8+ T cells are involved in the pathogenesis of RE. 相似文献
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Shen Jia-Yuan Li Man Xie Lyu Mao Jia-Rong Zhou Hong-Ning Wang Pei-Gang Jiang Jin-Yong An Jing 《中国病毒学》2021,36(1):145-148
正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016). 相似文献
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Renfei Lu Xiuming Wu Zhenzhou Wan Yingxue Li Lulu Zuo Jianru Qin Xia Jin Chiyu Zhang 《中国病毒学》2020,35(3):344-347
In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans. 相似文献