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《中国麻业》2019,(1)
为优化大麻叶总黄酮提取工艺并评估大麻叶总黄酮抗氧化活性,研究在单因素试验基础上,以提取时间、提取温度、料液比和乙醇体积分数为影响因素,总黄酮浸提量为评价指标,采用响应面试验设计优化提取工艺。采用FRAP总抗氧化能力测定试验、DPPH自由基清除试验以及ABTS自由基清除试验对总黄酮提取物进行抗氧化活性评价。结果表明:提取大麻叶总黄酮的最佳工艺条件为乙醇体积分数50%、料液比1∶20(g/m L)、提取时间2.0 h、提取温度70℃。在该最优提取条件下,大麻叶总黄酮浸提量为14.28 mg/g。抗氧化试验表明,大麻叶总黄酮的总抗氧化能力相当于1.288 mmol/L Fe SO4,对DPPH自由基的清除能力(IC50=3.7μg/m L)低于VC的清除能力(IC50=2.3μg/m L),而对ABTS自由基的清除力相当于0.391 mmol/L的Trolox。该工艺提取大麻叶得到的总黄酮含量较高,且具有一定的抗氧化性,可为未来大麻叶总黄酮的开发提供一定的科学依据。 相似文献
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《中国麻业》2020,(3)
以菜用黄麻叶为原料,采用冷凝回流法提取黄麻叶中总多酚,通过控制反应温度、反应时间、液料比、乙醇体积分数4个因素来优化黄麻叶中总多酚提取方法,采用响应面法优化黄麻叶总多酚提取工艺。此外,对黄麻提取液进行抗氧化试验。结果表明,各因素对总多酚提取量的影响大小为:液料比反应温度乙醇体积分数反应时间,黄麻叶总多酚最佳提取工艺条件为:反应温度90℃、反应时间2.5 h、液料比30∶1(mL/g)、乙醇体积分数50%,在该条件下黄麻总多酚提取量为13.400 mg/g。此外,黄麻提取液对1,1-二苯基-2-三硝基苯肼(DPPH)、2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(ABTS)和铁离子还原/抗氧化能力(FRAP)均有一定的抗氧化能力。研究结果将为菜用黄麻的药用提供理论依据。 相似文献
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以莲子干品为原料,在单因素试验的基础上,通过正交试验确定了乙醇提取莲子多酚类物质的最佳工艺条件为乙醇浓度90%、液料比1∶10、微波功率300 W、提取时间35 s、提取3次。在此条件下浸提,莲子多酚提取率为7.74 mg·g^-1。 相似文献
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研究木奶果果皮多酚水浴振荡辅助提取工艺及其体外抗氧化活性。在单因素试验基础上,采用响应面法优化木奶果果皮多酚的水浴振荡辅助乙醇提取工艺,并以V_C为对照,对DPPH自由基、ABTS自由基和超氧阴离子自由基清除能力进行探讨。结果表明:采用优化后的工艺条件,提取时间63 min、提取温度65℃、乙醇浓度66%、液料比42∶1(m L/g),木奶果果皮多酚提取量为31.2 mg/g,与模型预测值31.0 mg/g相近,最佳工艺实用性强。体外抗氧化活性实验表明,木奶果果皮多酚对于DPPH自由基、ABTS自由基和超氧阴离子自由基的IC50值分别为12.3、2.35、0.141 mg/m L,最高清除率分别为90.6%、99.1%和61.9%,说明木奶果果皮多酚具有很强的抗氧化活性。 相似文献
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以枇杷叶为试材,在单因素试验基础上,采用响应面分析法,建立料液比、乙醇浓度、提取温度和提取时间等4个因素影响枇杷叶多酚提取率的二次多项回归模型,并验证该数学模型的有效预测性。结果表明:料液比、提取温度、提取时间是影响枇杷叶多酚提取率的主要因素;随着料液比和提取温度的增加,枇杷叶多酚提取率呈先上升后下降的趋势,二者交互作用差异具有统计学意义。试验检验了枇杷叶多酚的最佳提取条件为:料液比1∶21(g∶m L)、乙醇浓度48.5%、温度60℃、浸提时间2.6 h,获得提取率为3.40%,该值与理论预测值3.44%接近,证明该模型可较好的指导枇杷叶多酚的提取条件。 相似文献
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2种提取工艺对橄榄果实多酚含量及抗氧化活性的影响 总被引:1,自引:0,他引:1
以橄榄果实为原料,利用正交实验探讨有机溶剂和超声波提取对多酚提取量和总还原力FRAP的影响,并分析比较2种提取方法,以确定最佳提取条件和参数。结果表明:有机溶剂提取的最佳工艺参数料液比为1∶60、提取时间60 min、提取温度60℃、乙醇浓度50%,其多酚提取量和总还原力FRAP分别为79.07 mg/g和740.45μmol/g。超声波提取的最佳工艺参数料液比1∶40、提取时间20 min、超声功率180 W及乙醇浓度60%,该条件下多酚提取量和总还原力FRAP分别为85.26 mg/g和952.27μmol/g。超声波提取具有多酚提取量高、抗氧化活性强、提取时间短、溶剂耗量少的特点,优于有机溶剂提取。 相似文献
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Sena L.P. VanderJagt D.J. Rivera C. Tsin A.T.C. Muhamadu I. Mahamadou O. Millson M. Pastuszyn A. Glew R.H. 《Plant foods for human nutrition (Dordrecht, Netherlands)》1998,52(1):17-30
In the western Sahel, indigenous plants become important staples when cereal harvests are inadequate to support populations inhabiting that region of Africa. The purpose of this study was to assess the nutrient content of several of these edible wild plants. The leaves of the following seven plant foods were analyzed: Ziziphus mauritiana, Cerathotheca sesamoides, Moringa oleifera, Leptadenia hastata, Hibiscus sabdarifa, Amaranthus viridi, and Adansonia digitata. The fatty acid, vitamin E, carotenoid, selected mineral and amino acid contents of these plant foods were determined. These same analyses were performed on the fruit of the Adansonia digitata. In quantitative and qualitative terms, Amaranthus viridis was found to be an excellent source of protein. Its amino acid composition compared favorably to that of a World Health Organization (WHO) protein standard. It also contained considerable amounts of the two fatty acids that are essential in humans (linoleic and -linolenic) and a number of minerals including iron, magnesium, calcium and zinc. The leaves of Hibiscus sabdarifa contained an appreciable quantity of protein the composition of which was comparable to the WHO standard. The mineral content of the leaves of this plant was also exceptionally high; noteworthy was its high zinc content. H. sabdarifa also contained significant quantities of the two essential fatty acids. Ziziphus mauritiana was an excellent source of the essential fatty acid linoleic acid and several of the metals including iron, calcium, magnesium and zinc. Its content of other essential nutrients, however, was rather low. In general, Adansonia digitata leaves were nutritionally superior to the fruit of the tree; however, the fruit did contain useful quantities of potassium, phosphorus, zinc and -linolenic acid. The Leptadenia hastata leaves were an especially good source of lutein and -carotene. These data should be useful to the people who inhabit the western Sahel in helping them devise healthy diets during times when cereal staples are in short supply. 相似文献
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通过电解质外渗法和匍匐茎恢复试验对‘阳江’狗牙根及其12个通过形态鉴定选出的坪用价值高且花序密度低的诱变后代进行抗寒性鉴定。电解质外渗法结果表明:诱变后代间的抗寒性具有较大差异,其叶片半致死温度(LT50)的变异范围为-7.6~-0.2℃(最低值与最大值相差7.4℃);参试材料抗寒性由强到弱依次为M18>M4>M26>M28> M22>阳江>M29>M31>M10>M37>M16>M1>M25,其中,有5个诱变后代抗寒性优于亲本,分别是M18、M4、M26、M28、M22。匍匐茎恢复实验结果表明:诱变后代M1、M22、M26、M31、M25在0℃和-5℃低温胁迫后的恢复生长率都高于亲本,恢复能力均优于亲本;M10、M37、M28在-5℃低温胁迫下,恢复生长能力低于亲本,抗寒性相对较弱,M16和M4在0℃和-5℃低温胁迫下,恢复生长率都低于亲本,抗寒性明显弱于亲本。综合2种方法鉴定结果显示:诱变后代M1、M25的恢复能力较强;M4、M28的叶片抗寒性较好,青绿期较长;M22、M18、M26的叶片抗寒性和匍匐茎恢复能力均较强;M29,M31的叶片抗寒性和匍匐茎恢复能力与亲本相似;M10、M16、M37的叶片抗寒性和匍匐茎恢复能力均较弱,整体抗寒性较弱。 相似文献
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橡胶树丛枝病病原的抗血清制备与应用 总被引:5,自引:1,他引:4
以感染橡胶树丛枝病病原的长春花为材料,制备得到橡胶丛枝病病原菌抽提液,以抽提液为抗原免疫家兔,制备抗血清,经微量沉淀测定,抗血清效价为1:2048。应用橡胶丛枝病抗血清检测橡胶褐皮病,无症苗木检出率达30%-37%,可疑的褐皮病树检出率达85.7%。 相似文献
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R. W. Summers 《Crop Protection》1989,8(6):451-454
One hundred and fifty-six pre-roost gatherings of starlings were observed at 28 sites around a roost in west Norfolk during winter. Pre-roost gatherings occurred more frequently at individual farmyards compared with individual fields, but 82% of the sites where gatherings occurred were on fields. The size of gatherings was greater, the closer to the roost. Birds in pre-roost gatherings on fields of autumn-sown winter wheat spent most of the time feeding and had a diet composed almost exclusively of wheat seeds. Birds in gatherings on grass fields also fed intensively whereas only 31% of birds at farmyards were feeding. The implications that these results have with regard to potential damage to fields of winter wheat and around farmyards are discussed. 相似文献
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以‘福桐’、‘绿桐’2个无性系与10个不同种源的白花泡桐个体为研究对象,采用ISSR分子标记对12份白花泡桐材料的亲缘关系进行研究,并利用DPSv3.01进行聚类分析。结果表明:10条引物共扩增出66条条带,其中有37条多态带,多态性比例为56.1%。根据ISSR聚类分析结果,在遗传距离为0.35时,12份白花泡桐材料可分为5类,第1类为‘福桐’无性系与河南、河北种源个体;第2类为‘绿桐’无性系与湖南、湖北、江苏种源个体;第3类为浙江、广东种源个体;第4类为江西、福建种源个体;第5类为广西种源个体。此结果 相似文献
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Insect pest management is facing the economic and ecological challenge worldwide due to the human and environmental hazards caused by majority of the synthetic pesticide chemicals. Identification of novel effective insecticidal compounds is essential to combat increasing resistance rates. Botanicals containing active insecticidal phytochemicals appear to be promising to address some of these problems. Therefore, there is a continuous need to explore new active molecules with different mechanisms of action. Secondary metabolites present in plants apparently function as defense (toxic), which inhibits reproduction and other processes. The phytochemical biomolecules could be used for maximizing the effectiveness and specificity in future insecticide design with specific or multiple target sites, while ensuring the economic and ecological sustainability. In this article, the current state of knowledge on phytochemical sources and insecticidal activity, their mechanism of action in insects, resistance, and promising advances made in phytochemical research are reviewed. 相似文献
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为深入研究昆虫病原真菌蝉拟青霉疏水蛋白PChyd基因的功能,根据蝉拟青霉基因组信息克隆疏水蛋白PChyd基因,对该基因序列进行生物信息学分析,使用qRT-PCR技术对其在不同培养条件或阶段下的表达模式进行分析,并通过酶切酶连的方法构建了该基因的敲除载体。结果表明:PChyd基因的开放阅读框序列全长303 bp,编码100 aa,包含22 aa的信号肽序列和70 aa疏水蛋白功能区域。系统发育分析显示该基因与粗糙虫草菌亲缘关系最近。qRT-PCR结果显示PChyd基因在PDA培养的菌丝体、诱导的附着胞、诱导的芽生孢子中表达量显著高于另外2个样品,其中芽生孢子表达量最高,暗示该基因在蝉拟青霉侵染初期和在昆虫血腔中定殖阶段可能具有重要作用。凝胶电泳结果表明,成功构建了该基因的敲除载体,扩增出含有上臂、HPH、下臂的3356 bp左右的片段。本研究为进一步探究蝉拟青霉疏水蛋白PChyd基因的致病机理、生防工程菌的改造奠定了基础。 相似文献