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71.
不同肥料类型及成熟度对烤烟香气物质成分及香型的影响   总被引:45,自引:1,他引:45  
烟草香气是评价烟叶质量的重要因素之一。本项研究对烤烟复气物质主要成分进行了定性鉴定,共得出九类36种成分。含量较大的是新植二烯、烟碱、茄酮等。香型评定认为,苯乙醛、苯乙醇等对烟香贡献较大。 对香气物质主要成分的定量研究表明: (1)在不同肥料处理下,苯乙醛、2-呋喃甲醛等十种成分的含量均呈纯有机  相似文献   
72.
目的 基于超高效液相色谱–四极杆飞行时间–质谱(UHPLC–QTOF–MS)技术分析五倍子中单宁成分,建立一种有效的五倍子单宁成分测定方法,并解析单宁的裂解规律。 方法 使用高温和超声波辅助方法提取五倍子中的酚类化合物,基于二级质谱推定化合物的裂解途径。 结果 共鉴定到20种化合物,包含14种没食子单宁、3种酚酸、2种没食子酸酯和1种黄烷醇。以高温121℃为提取条件,均未鉴定到分子质量高于1 500 Da的没食子单宁,而在超声波辅助提取的五倍子水提取液中,成功地检测到1–O–没食子酰基葡萄糖至14–O–没食子酰基葡萄糖,其中,超声功率1 500 W,提取温度65℃条件下,鉴定到更多的没食子单宁异构体。MS/MS图谱显示,五倍子单宁主要通过没食子酸、没食子酰基、糖苷、水、羧基的损失进行裂解。 结论 本研究证明,超声波辅助提取条件下,应用UHPLC–QTOF–MS技术能够全面高效地分析五倍子中的单宁成分,本研究为富含单宁的植物的化学成分研究提供参考依据。  相似文献   
73.
Total methanolic extracts of Saponaria vaccaria seed derived from several varieties, as well as various purified components obtained through successive chromatographic separations of total extracts were evaluated for their growth inhibitory activity in WiDr (colon), MDA-MB-231 (breast), NCI-417 (lung) and PC-3 (prostate) human cancer cells as well as the non-tumorigenic fibroblast BJ (CRL-2522) cell line using MTT colorimetric assay. Purified bisdesmosidic saponins segetoside H and I were further examined using microscopy and apoptosis assays. Bisdesmosidic saponins exhibited dose-dependent growth inhibitory and selective apoptosis-inducing activity. Growth inhibitory effects were particularly strong in a breast (MDA-MB-231) and a prostate (PC-3) cancer cell line. Total extracts exhibited a different preference being most active against a colon cancer cell line (WiDr). In a comparison of varieties, all of the total seed extracts exhibited similar dose-dependent activities, but with some variation in potency. Monodesmosidic saponins vaccarosides A and B, phenolic vaccarin, and cyclopeptide segetalin A, co-occurring seed substituents, did not exhibit activity. The non-tumorigenic fibroblast cell line BJ (CRL 2522) was growth inhibited but did not undergo apoptosis when treated with bisdesmosidic saponins at low micromolar concentrations. Saponin-rich extracts from Kochia scoparia seed and Chenopodium quinoa were also evaluated alongside Saponaria saponins but did not exhibit activity. Closely related Quillaja saponins exhibited activity but were less potent.  相似文献   
74.
Tian S  He G  Song J  Wang S  Xin W  Zhang D  Du G 《Fitoterapia》2012,83(3):532-540
Baicalein, a flavonoid originally isolated from the root of Scutellaria baicalensis Georgi, has numerous pharmacological activities. Up to now, several studies regarding the pharmacokinetic profiles of baicalein have been described, while there is no such study reported in monkey, the species which is more similar to human. The purpose of this study was to investigate the pharmacokinetic profiles of baicalein after oral administration in monkeys. After orally administrating three doses of baicalein in monkeys, multi-peaks of the plasma concentration-time curves were observed and the non-linear pharmacokinetics for baicalein and its metabolite baicalin were found at doses of 50-500mg/kg. In order to calculate the absolute bioavailability, the intravenous pharmacokinetic study was also carried out after intravenous administration of 10mg/kg baicalein. The absolute bioavailability of baicalein in different doses was ranged from 13.1% to 23.0%. In this study, baicalein and baicalin were determined by LC-MS method. The chromatographic separation was performed on Agilent Poroshell 120 SB-C18 column (2.7μm, 2.1×50mm). Baicalein and baicalin were detected by single quadrupole mass spectrometer equipment with electrospray ionization interface with the selected ion monitoring mode. The assay was linear for both baicalein and baicalin with the correlation coefficients>0.99. The intra- and inter-day precisions for baicalein and baicalin were all less than 15% by relative standard deviation. The analytes were stable during samples storage and handling, and no matrix effects were observed. The method we developed in this study was sensitive, precise, stable and producible.  相似文献   
75.
用虎纹凤梨母株两侧的蘖芽经消毒处理后接种到MS+6-BA 1.0 mg/L+IAA 0.3 mg/L的培养基中,诱导出愈伤组织。而后用改良MS培养基+6-BA 0.3 mg/L+NAA 0.01 mg/L从愈伤中诱导出小芽并继代培养,扩繁。增殖率3.0~4.0倍。续代3~5代后从芽团上选取H>2.5 cm的粗壮单株仍用改良MS培养基+6-BA 0.3 mg/L+NAA 0.01 mg/L扩繁,增殖倍数2~3倍。而芽团上H<2.5 cm的丛芽分成具2~3个芽的小芽团用改良MS培养基+6-BA 0.05 mg/L+IAA 0.01 mg/L+C 100 mg/L使其长高长粗壮,增殖倍数1.5倍,经过一段时间的培养后切取达到生根标准的单株接到1/4 MS+IAA 0.3 mg/L+NAA 0.05 mg/L+C 500 mg/L培养基中,30~40 d生根率达95%以上。炼苗20 d左右移栽,成活率达85%~90%以上。  相似文献   
76.
This study aims to evaluate the chemical composition of wood and extractives of Pinus taeda and Schizolobium parahyba (guapuruvu) as potential feedstock for new applications in the biorefinery industry. For this purpose, their content of α-cellulose, hemicellulose, insoluble lignin, hot water solubility, NaOH1% solubility, inorganic materials (ash), and monomeric sugars by high-performance liquid chromatography was quantified. Attenuated total reflectance infrared spectroscopy and thermogravimetric analysis were also used to complete the physicochemical characterization of the studied woods. The extractives were obtained by soxhlet extraction with ethanol:toluene and dichloromethane and identified with pyrolysis-gas chromatography/mass spectroscopy technique. The results showed that guapuruvu wood has the higher amount of hemicellulose (16%) when compared to pine wood (10%), which resulted in higher solubility in alkali solution. Furthermore, in relation to other biomasses, the two woods presented more percentage of lignin and minor content of hemicelluloses. The P. taeda wood presented the highest percentage of extractives mainly composed of fatty acids and aromatic hydrocarbons, while guapuruvu wood had a higher percentage of phenolic compounds and also fatty acids. Both the materials have low content of extractives with dichloromethane and were mainly composed of lipophilic compounds.  相似文献   
77.
油茶饼粕是油茶种子制备茶油后的副产物,含有多种生物活性成分。为给油茶饼粕资源的高效利用提供理论依据,采用索氏抽提方法,以乙醇为浸提溶剂,对冷冻干燥除水后的油茶饼粕进行浸提,对其提取物和提取残渣进行真空浓缩干燥处理,并在600℃的条件下分别进行热裂解,然后对热裂解产物的组分进行热裂解-气质联用(Py-GC/MS)分析。结果表明:油茶饼粕乙醇提取物的热裂解组分中含有杂环类、酮、酯、酚、烃类、醛等成分,而其提取残渣的热裂解组分中含有杂环类、酮、酸、酯、醚、酚、糖类、氨基酸、腈等成分;油茶饼粕乙醇提取物与提取残渣的热裂解产物中的部分组分可用作生物医药、香料、化妆品的生产原料。  相似文献   
78.
为建立有效的阻燃剂的使用规范和为监管制度提供理论依据,本文建立了微波辅助萃取,液相色谱串级质谱法同时测定木制品中3种有机磷阻燃剂分析方法,并考察了萃取溶剂、萃取条件、流动相对试验结果的影响。结果表明,以丙酮为萃取溶剂,70℃微波辅助萃取30 min,利用多反应检测MRM模式,TCEP、TDCP在线性范围0.02~1.0 mg/kg,TCPP在线性范围0.002~0.2 mg/kg内质量浓度与响应值呈现良好的线性关系,定量下限分别为27、50、8μg/kg,加标回收率82.7%~98.3%,相对标准偏差1.8%~10.8%。该方法操作简单,提取效果较好,能够有效的检测木制品中三种有机磷酸酯阻燃剂。  相似文献   
79.
采用水蒸气蒸馏法提取毛黄肉楠(Actinodaphne pilosa(Lour.)Merr.)挥发油。经气相色谱—质谱联用仪(GC/MS)分析,共鉴定出75种挥发性化合物,用气相色谱峰面积归一法测定各组分的相对质量分数。结果表明,其主要成分分别为喇叭茶烯(12.72%)、萘,1,2,3,4,4a,5,6,8a-八氢-7-甲基-4-亚甲基-1-(1-甲基乙基)-,(1a,4aa,8aa)-(12.33%)、大根香叶烯-D(11.58%)、trans-石竹烯(10.66%)和兰桉醇(5.89%)等。  相似文献   
80.
油松幼枝 (松笔头)挥发性成分的分析   总被引:9,自引:0,他引:9  
采用水蒸气蒸馏法对辽宁产油松幼枝(松笔头)的挥发性成分进行提取,采用GC/MS方法对提取的挥发性成分进行了分离、鉴定,共鉴定了25个化学万分,挥发油得率约为2.1%。  相似文献   
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