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1.
在整理保存于中国科学院植物研究所标本馆(PE)国产合瓣花植物模式标本时,根据《国际藻类、菌类、植物命名法规》(墨尔本法规)规则9.5,我们发现在忍冬科中长柄金花忍冬、红花岩生忍冬、唐古特忍冬和肉叶荚蒾,在败酱科中小花缬草和小缬草,在川续断科中裂叶翼首花,以及在菊科中的糙毛兔儿风、铃铃香青、乳白香青、球花蒿、尖苞艾纳香、天目山蟹甲草、盘花垂头菊、矮垂头菊、香芸火绒草、红花火绒草、毛冠菊、大槲叶雪兔子、秋海棠叶蟹甲草、瓜拉坡蟹甲草、箭叶橐吾、华蟹甲和亚灌木状川甘亚菊名称模式为合模式。遵照规则8.1、9.11和9.12,以及辅则9A.3精神,本文对这24个名称做出后选模式指定。  相似文献   

2.
为对香芸火绒草(Leontopodium haplophylloides)的化学成分进行分离纯化及抗炎活性研究,本实验通过正、反相硅胶柱色谱、Sephadex LH-20凝胶柱色谱,从香芸火绒草的中分离得到17个化合物,并运用现代波谱技术(1H NMR、13C NMR)分别鉴定为:咖啡酸(1)、咖啡酸-β-苯乙醇酯(2)、原儿茶酸(3)、tyrosol(4)、对羟基苯甲酸(5)、邻苯二甲酸二丁酯(6)、异莨菪亭(7)、7-(2,3-epoxy-3-methyl-3-butyloxy)-6-methoxycoumarin(8)、洋芹素(9)、牡荆素(10)、5-羟基-4',7-二甲氧基-6,8-二甲基黄酮(11)、5,7-二羟基-8-甲氧基黄酮(12)、百蕊草素Ⅲ(13)、methyl flavogallonate(14)、3,5,7,3',4'-pentahydroxyflavone (15)、木犀草素(16)、高良姜素(17),其中化合物1~16为首次从该植物中分离得到;经抗菌筛选发现发化合1、2、4~6、9、10、13~17对大肠杆菌、金黄色葡萄球菌及蜡状芽孢菌有抑制作用。  相似文献   

3.
亚高山地区香芸火绒草挥发油的研究   总被引:2,自引:0,他引:2  
对甘肃产野生香芸火绒草采用SED和萃取两种方法提取精油和浸膏,测得精油平均得率0.037%,浸膏1.18%,净油53.4%。精油有65种组分,评香鉴定认为,具有醛香、清香、甜香,香气浓强。研究分析表明,该植物可成为一种新的生产天然香精香料的原料来源。  相似文献   

4.
目的:深入调查研究辽宁地区药用植物火绒草的分布、资源及使用概况,为火绒草的合理开发利用提供依据.方法:采用文献查阅方法、野外样线调查和样地、样方调查相结合的方法,对以昌图县为代表性地区及辽宁其他地区火绒草的分布区域、生长情况及生态环境等进行调查分析.结果:辽宁为火绒草主要分布区,主要生长在干旱、向阳环境,多分布在沈阳、...  相似文献   

5.
研究植物种群的分布格局及空间关联性是揭示植物种群与环境间关系、自身特性以及种间相互作用的一种重要手段。本研究以甘南高寒草甸为对象,沿海拔梯度(2900、3500、3800 m)设置3个样地,采用Ripley K函数对不同海拔矮嵩草(Kobresia humilis)与火绒草(Leontopodium nanum)种群的空间分布格局及种间关联性进行了分析。结果表明:(1)随着海拔的上升,矮嵩草种群的重要值、盖度、株数等呈递增趋势,火绒草种群的重要值、盖度、株数等则呈递减趋势。(2)矮嵩草种群在不同海拔的研究尺度内均表现为聚集分布,但其聚集的程度有所不同;火绒草种群在海拔2900 m处呈聚集分布状态;海拔3500 m处,火绒草种群在0~2.8 m尺度上呈聚集分布,但其聚集强度随着研究尺度的增加而逐渐减弱,最终转变为随机分布; 3800 m处,火绒草种群在0~2 m尺度内呈聚集分布,在较大尺度(2~5 m)上呈随机分布。(3)海拔2900 m处,矮嵩草与火绒草种群在小尺度(0~1.1 m)内表现为正相关,较大尺度上表现为无相关;海拔3500 m处,在整个研究尺度内表现为负相关;海拔3800 m处,在小尺度范围(0~1.4 m)内表现为无相关,较大尺度上表现为负相关,且随研究尺度的增大,其关联性增强。  相似文献   

6.
以青藏高原两种生境(阴坡和阶地)和4个斑块大小等级水平(等级1:0.2—0.6m2,G1;等级2:0.6—2 m2,G2;等级3:2—3.6 m2,G3和等级4:3.6—8.6 m2,G4)的火绒草(Leontopodium nanum)群落为对象,利用幂乘方法则,分析了其种群和群落空间异质性和群落物种多样性特征,明晰了优势种、亚优势种、伴生种和偶见种对其植被分布格局的影响。结果表明:各火绒草斑块的群落空间分布格局均呈集群分布,植物种的随机出现频率和实际出现频率的方差对数值与其幂乘方法吻合性较高(R2﹥0.8),幂乘方法能对火绒草斑块植被空间分布格局进行客观分析。优势种火绒草和线叶嵩草(Kobresia capillifolia),亚优势种球花蒿(Artemisia smithii)和珠芽蓼(Polygonum viviparum)等的相对空间异质性(ε)高于群落的空间异质性(δC),位于直线y=0上方,使群落趋于集群分布;伴生种西北针茅(Stipa krylovii)、瑞香狼毒(Stellera chamaejasme)和苔草(Carex sp)等的ε与群落的δC类似,位于直线y=0附近,它们维持群落自身空间分布状态;偶见种的ε低于群落的δC,位于直线y=0下方,降低群落的集群分布。随火绒草斑块等级水平的增加,群落物种数呈增加,丰富度指数DGI呈降低变化。一般火绒草斑块的δc和βw为阶地﹥阴坡,DGI为阶地﹤阴坡;两种生境下,植物种组成的相似性G1斑块较低,G2—G4斑块较高。火绒草斑块的群落分布格局主要由优势种和亚优势种及偶见种的ε决定。  相似文献   

7.
目的:分析也门与中国产香丝草挥发油的化学成分,比较两者差异。方法:采用水蒸气蒸馏法提取也门及中国产香丝草的挥发油,运用气相色谱-质谱联用法(GC—MS)对挥发油进行组分分析,将两者的成分差异进行了比较。结果:从也门产香丝草挥发油中鉴定了34个成分,相对含量最多的分别为醇类(47.77%)、烯类(29.15%)、酯类(9.64%),主要为雪松烯醇(18.54%)和环氧化香橙烯(18.75%);从中国产香丝草挥发油中鉴定了56个成分,以酯类(31.20%)、烯类(28.05%)、醇类(14-29%)等挥发性物质为主,包括异戊酸香叶酯(18.81%)、反式--佛手柑油烯(10.31%)。结论:也门与中国产香丝草挥发油的组成具有较大的差异,是两者香味迥异的物质基础,也是也门产香丝草制作香料、美食的科学依据;  相似文献   

8.
报道我国青藏高原东南缘5种6个居群火绒草属植物的染色体数目和核型.银叶火绒草Leontopodium souliei 2n =2x=24=13M+8m+3sm,1B;坚秆火绒草L.franchetii 2n=2x=26=6M+ 18m +2sm,2A;华火绒草L.sinense;四川木里海拔2406m的居群:2n=2x=26=4M+22m,1B,四川木里海拔3074m居群:2n=4x=52=16M+36m,1B;美头火绒草L.calocephalum 2n=4x=48=3M+43m +2sn,1B;毛香火绒草L.stracheyi 2n=4x=48=13M+35m,1A.对现有的染色体资料分析表明:火绒草属的染色体核型比较对称,但种间具一定的变异;多倍化可能是该属在我国青藏高原及其周边地区发生强烈物种分化的重要原因之一.  相似文献   

9.
不同海拔火绒草光合特性的研究   总被引:6,自引:0,他引:6  
对生长于青藏高原东北部3个不同海拔地区(2300、2700和3800m)的火绒草叶片的光合特性进行了比较研究。结果发现,随着海拔的升高,叶绿素含量有降低的趋势,而叶绿素a/b比值及类胡萝卜素相对含量呈上升趋势。与海拔2300m处的相比,生长于海拔3800m处的火绒草的净光合速率、表观量子效率和光补偿点较低,但光饱和点较高。研究表明,火绒草在光合特性上的变化是对逆境的一种适应.是青藏高原特殊生态条件长期胁迫的结果。  相似文献   

10.
为了解不同提取方式对香露兜挥发性成分的影响,以采自海南兴隆的香露兜成熟鲜叶为研究对象,采用100%甲醇蒸馏法、75%乙醇蒸馏法、100%乙醇蒸馏法、75%乙醇超声波辅助法、100%乙醇超声波辅助法、75%乙醇浸提法和100%乙醇浸提法7种不同方式进行提取,利用气相色谱-质谱法(GC-MS)测定各提取物的挥发性成分,并结合主成分分析(PCA)和相关分析(CA)对其组成和含量差异进行比较分析。结果表明,7种不同提取方式共鉴定出52种挥发性成分,主要由酯类、醇类、酮类、烯烃类、吡咯类物质组成,100%甲醇蒸馏法未检测出关键特征香气物质2-乙酰-1-吡咯啉(2-AP),其余6种方式提取物均有检出,含量变幅为1.21~37.48μg/g;7种香露兜提取物相关性系数平均值为34.80%±7.20%,PCA分析将7种提取方式分为3组:75%、100%乙醇超声波辅助提取法和75%、100%乙醇浸提法主要挥发性成分为叶绿醇、角鲨烯、3-羟基-2-丁酮、棕榈酸乙酯、羟基丙酮、3-甲基-2-(5H)-呋喃酮和2-AP,75%和100%乙醇蒸馏提取法主要挥发性成分为硬脂酸甲酯、2-AP、(E)-7-四癸醇和棕榈酸甲酯,100%甲醇蒸馏提取法主要挥发性成分为(Z)-十六烯酸甲酯、苯乙烯、十四酸甲酯、十五碳酸甲酯。由此说明,香露兜7种不同方式提取物3个组间挥发性成分的组成和含量存在差异,这为香露兜产品精深加工提供了理论依据。  相似文献   

11.
The osmanthus volatile oil was welcomed by consumers even if the high price since the unique and pleasant odor. Meanwhile, the low yield of osmanthus volatile oil restricts industrial production. In this work, an osmanthus volatile oil was obtained by means of a novel ultrasonic-assisted flash extraction method and was compared with the oil from hydrodistillation and supercritical fluid extraction on yield, aroma, and biological activities. The volatile oil obtained from the ultrasonic-assisted flash extraction was obtained with the petroleum ether and got a high yield at 3.51 % within a 40-min process, an increase of nearly 81 % from the single solvent extraction. This oil also showed a high aroma intensity and aroma compound concentration. Meanwhile, the oil also has the highest antioxidant ability but lower antibacterial activity against oil from hydrodistillation. It was considered that this work was helpful for the optimization of the extraction method of osmanthus volatile oil.  相似文献   

12.
The characteristic aroma compounds of Citrus natsudaidai Hayata essential oil were evaluated by a combination of instrumental and sensory methods. Sixty compounds were identified and quantified, accounting for 94.08% of the total peel oil constituents. Limonene was the most abundant compound (80.68%), followed by gamma-terpinene (5.30%), myrcene (2.25%) and alpha-pinene (1.30%). Nineteen compounds which could not be identified in the original oil were identified in the oxygenated fraction. Myrcene, linalool, alpha-pinene, beta-pinene, limonene, nonanal, gamma-terpinene, germacrene D, and perillyl alcohol were the active aroma components (FD-factor > 3(6)), whereas beta-copaene, cis-sabinene hydrate and 1-octanol were suggested as characteristic aroma compounds, having a Natsudaidai-like aroma in the GC effluent. Three other compounds, heptyl acetate, (E)-limonene oxide and 2,3-butanediol, which each showed a high RFA value (>35) were considered to be important in the reconstruction of the original Natsudaidai oil from pure odor chemicals. The results indicate that 1-octanol was the aroma impact compound of C. natsudaidai Hayata peel oil.  相似文献   

13.
The characteristic aroma compounds of Citrus natsudaidai Hayata essential oil were evaluated by a combination of instrumental and sensory methods. Sixty compounds were identified and quantified, accounting for 94.08% of the total peel oil constituents. Limonene was the most abundant compound (80.68%), followed by γ-terpinene (5.30%), myrcene (2.25%) and α-pinene (1.30%). Nineteen compounds which could not be identified in the original oil were identified in the oxygenated fraction. Myrcene, linalool, α-pinene, β-pinene, limonene, nonanal, γ-terpinene, germacrene D, and perillyl alcohol were the active aroma components (FD-factor > 36), whereas β-copaene, cis-sabinene hydrate and 1-octanol were suggested as characteristic aroma compounds, having a Natsudaidai-like aroma in the GC effluent. Three other compounds, heptyl acetate, (E)-limonene oxide and 2,3-butanediol, which each showed a high RFA value (>35) were considered to be important in the reconstruction of the original Natsudaidai oil from pure odor chemicals. The results indicate that 1-octanol was the aroma impact compound of C. natsudaidai Hayata peel oil.  相似文献   

14.
This study aimed to check the hypothesis that aroma concentration in the aqueous phase of an oil-in-water emulsion controlled the odor intensity of single aroma compounds. A set of flavored oil-in-water emulsions, prepared according to a 22 experimental design (aroma concentration, oil volume fraction) with two central points, was assessed for odor intensity by a 24-member panel during four sessions. In each session, three of the four-studied aroma molecules (benzaldehyde, ethyl butyrate, linalool and acetophenone) were investigated. Whatever the aroma, the experimental data showed that the oil volume fraction of the emulsion (from 0.12 to 0.48) did not influence the odor intensity. For each emulsion composition, aroma concentrations at equilibrium in both phases were calculated using the oil-water partition coefficient of the compound. Odor intensities, estimated from aroma concentration in the aqueous phase using previously reported modeling of odor intensity above water solutions, were then compared to experimental data. It is confirmed that the perceived odor intensity is governed by the aroma concentration in the aqueous phase at the time of the trial and not by the averaged apparent concentration in the emulsion.  相似文献   

15.
The present study explored the possibility that aroma components generated by the oxidation of olive oil may enhance the palatability of olive oil. Using a mouse behavioral model, we found that olive oil oxidized at room temperature for 3 weeks after opening the package, and heated olive oil were both significantly preferred over non-oxidized olive oil. Furthermore, this preference was enhanced with an additive of oxidized refined olive oil flavoring preparation at a certain concentration. These results suggest that the aroma of oxidized fat might be present in most fats, and might act as a signal that makes possible the detection of fats or fatty acid sources.  相似文献   

16.
A computerized time intensity procedure was used to evaluate the retronasal aroma intensity of vanillin and limonene in oil/water emulsion. The maximum perceived retronasal intensity of limonene was decreased as oil content in the emulsion increased, but temporal perception (time to maximum intensity and total duration of perception) was not affected. Total duration of vanillin retronasal aroma increased as oil content increased, and salivary flow rate had a significant effect on perception of vanillin aroma. These results suggest that time intensity measurements may be a valuable tool for evaluating the effects of matrix interactions on retronasal aroma intensity.  相似文献   

17.
香叶油的化学成分   总被引:12,自引:0,他引:12  
为了探讨不同产地香叶油的香气特徵,我们对云南省昆明、玉溪、石屏、宾川产香叶油和法国波尔蓬,埃及产香叶油的化学成分用Finnigan-4510型气相色谱/质谱/计算机联用方法进行了定性、定量分析,共分离鉴定了35个成分(见表2)。 分析结果表明:云南产香叶油的香气成分主要由香茅醇,甲酸香茅酯,香叶醇,玫瑰醚构成;而法国、埃及产香叶油的香气成分则主要由香叶醇,甲酸香叶酯,香茅醇,甲酸香茅酯和芳樟醇构成。二者具有不同的格调和香气特徵。  相似文献   

18.
Using an intensity rating with no external calibration, experiments were designed to measure the sensory oil-water partition coefficients of four aroma molecules (benzaldehyde, ethyl butyrate, linalool and acetophenone) as the ratios of concentration producing stimuli of equivalent intensities. Flavored water and oil phases were successively assessed for odor intensity by 24 panelists who were given total freedom regarding scaling strategy. Each session combined five concentration levels of three out of the four studied aromas in a solvent (water or oil). A predominant concentration effect was found for each aroma in both solvents and concentration dependencies of perceived intensity above water and oil were similar. Experimental data were modeled with Fechner, Stevens and Hill equations. Combining results above water and oil solutions to feed a common model led to the evaluation of an overall sensory oil-water partition coefficient for each aroma compound. All three models produced similar partition coefficient values for each aroma that were lower than the related instrumental partition coefficients. Biases previously detected when external calibration had been used were reduced in a large proportion while suggested enhancement of odor intensity by water vapor could not be excluded.  相似文献   

19.
The aim of this study was to investigate the chemical composition and the odor‐active compounds of the essential oils from Evolvulus alsinoides, which is a well‐known edible and medicinal plant. The volatile compounds in the oils were identified by hydrodistillation (HD) and solvent‐assisted flavor evaporation (SAFE) in combination with GC, GC/MS, GC/O (=olfactometry), aroma extract dilution analysis (AEDA), and relative flavor activities (RFA values). The most abundant compound in the HD oil was cisα‐necrodol (12.62%), an irregular monoterpene with a cyclopentane skeleton, which is very unusual in the plant kingdom. In the SAFE oil, the main components included 2‐butoxyethanol (9.01%), benzyl alcohol (8.01%), and γ‐butyrolactone (7.37%). Through sensory analysis, 21 aroma‐active compounds were identified by GC/O. The most intense aroma‐active compounds in the HD oil were hexan‐1‐ol and γ‐nonalactone, both of which showed high RFA values. α‐Methyl‐γ‐butyrolactone and dimethyl sulfone contributed more strongly to the aroma of the SAFE oil. These results imply that the essential oils of E. alsinoides deserve further investigation in the food industry.  相似文献   

20.
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