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1.
测定河南和山西连翘叶中总木脂素、连翘酯苷A、连翘酯苷B和连翘苷含量。采用分光光度法测定连翘叶中总木脂素含量,结果显示山西连翘叶高于河南连翘叶总木脂素含量。采用高效液相色谱法(HPLC)测定连翘叶中连翘酯苷A、连翘酯苷B和连翘苷的含量。连翘酯苷A平均回收率为99.6%,RSD为1.23%;连翘酯苷B平均回收率为101.3%,RSD为1.74%;连翘苷平均回收率为102.3%,RSD为2.58%;连翘叶中连翘酯苷A和连翘苷的含量较高,并且不同产地连翘叶中连翘苷含量差异较大;另外对于富含连翘酯苷和连翘苷的连翘叶能否代替果实或者与果实合并用药有待于进一步研究。  相似文献   

2.
采用响应面分析法优化连翘叶中连翘酯苷A和连翘苷的最佳提取工艺条件,在单因素实验基础上,采用Box-Behnken中心组合设计原理研究液料比、乙醇浓度、浸提时间、浸提温度4个因素对连翘酯苷A得率和连翘苷得率的影响.利用Design Expert 8.0.5 b分析确定最佳提取工艺,根据实际条件,得到连翘酯苷A和连翘苷的最佳提取工艺为:乙醇浓度53%、提取温度74℃、浸提时间为53 min、液料比30 mL/g.回归模型预测最优条件下连翘酯苷A得率为7.53%,连翘苷得率为3.03%,验证值分别为7.56%,3.09%,与预测值的相对误差分别为0.4%,2.0%.  相似文献   

3.
中药连翘及连翘叶中连翘苷含量的比较研究   总被引:21,自引:0,他引:21  
用高效液相色谱法对不同产地的连翘叶、老翘、青翘中的连翘苷含量进行测定。结果表明:连翘叶中连翘苷含量比老翘高40倍以上,比青翘中连翘苷含量高2~4倍左右,不同产地的连翘叶、老翘及青翘中连翘苷的含量也有较明显的差别。  相似文献   

4.
测定河南和山西连翘叶中总木脂素、连翘酯苷A、连翘酯苷B和连翘苷含量。采用分光光度法测定连翘叶中总木脂素含量,结果显示山西连翘叶高于河南连翘叶总木脂素含量。采用高效液相色谱法(HPLC)测定连翘叶中连翘酯苷A、连翘酯苷B和连翘苷的含量。连翘酯苷A平均回收率为99.6%,RSD为1.23%;连翘酯苷B平均回收率为101.3%,RSD为1.74%;连翘苷平均回收率为102.3%,RSD为2.58%;连翘叶中连翘酯苷A和连翘苷的含量较高,并且不同产地连翘叶中连翘苷含量差异较大;另外对于富含连翘酯苷和连翘苷的连翘叶能否代替果实或者与果实合并用药有待于进一步研究。  相似文献   

5.
本文旨在开发一种微生物转化工艺,将连翘苷转化为活性更高的连翘脂素.结果从土壤中分离筛选到一株桔青霉(Penicillium citrinum)LB菌株,转化连翘苷为连翘脂素的专一性较高.经培养基主要组成和转化条件优化,得出较佳的产酶培养组成为:蔗糖7 g/L,(NH4)2 SO45 g/L,NaCl 5 g/L,KH2 PO45 g/L,MgSO41 g/L,MnSO40.5 g/L,pH 6.0.LB菌株经产酶培养后,过滤收集菌体悬浮于2倍发酵液体积的磷酸盐缓冲液中,加入2 g/L的底物连翘苷,于30℃、200 r/min转化20 h,连翘脂素的转化得率可达94.1%.利用微生物将连翘苷转化为连翘脂素,具有方法简单、转化得率高、产物容易纯化和副产物少等优点,有潜在的工业化应用价值.  相似文献   

6.
连翘苷和黄芩苷对表皮葡萄球菌生物膜抑制作用的研究   总被引:3,自引:0,他引:3  
目的通过中药有效成分连翘苷和黄芩苷分别对表皮葡萄球菌生物膜抑制作用的研究,为表皮葡萄球菌生物膜引起的相关感染提供新的治疗途径。方法体外构建表皮葡萄球菌生物膜,XTT减低法评价连翘苷、黄芩苷对表皮葡萄球菌初始黏附及生物膜内细菌代谢的影响,显微镜下观察用药后表皮葡萄球菌生物膜形态和结构改变。结果连翘苷和黄芩苷对表皮葡萄球菌生物膜的早期黏附均无抑制作用;连翘苷对表皮葡萄球菌生物膜菌的SMIC50为31.25μg/ml,而黄芩苷对表皮葡萄球菌生物膜菌的代谢无影响;在显微镜下观察,连翘苷使部分表皮葡萄球菌被膜的形态发生改变,而黄芩苷对其形态影响不显著。结论连翘苷对表皮葡萄球菌生物膜的初始黏附阶段无抑制作用,对生物膜菌的代谢和生物膜形态均有显著影响;黄芩苷对表皮葡萄球菌生物膜无显著作用。  相似文献   

7.
目的以β淀粉样蛋白损伤自然衰老小鼠建立一种新的复合式老年痴呆(AD)小鼠模型,观察连翘酯苷对复合模型学习记忆障碍的改善作用,并对其机制进行初步探讨。方法采用14月龄C57BL/6小鼠侧脑室注射Aβ25-35形成拟AD复合模型;Morris水迷宫实验观察小鼠学习记忆能力,实验结束取小鼠脑组织用放射免疫分析法检测TNF-α及IL-1的含量;Western blot方法检测GFAP蛋白表达,化学比色法测定ChAT、AchE、SOD酶活性及MDA的含量。结果水迷宫实验中连翘酯苷组可显著改善小鼠的学习记忆能力(P<0.05)。作用机制研究发现:连翘酯苷能降低TNF-α、IL-1的含量(P<0.05),抑制GFAP蛋白表达。提高ChAT、SOD酶活力,降低AchE活性及MDA的含量(P<0.05,P<0.01)。结论连翘酯苷对拟AD复合动物模型学习记忆的改善作用可能与抑制脑内炎症反应,调节胆碱能系统,抗氧化作用等有关。  相似文献   

8.
以高效液相色谱法,测定杜仲不同采收期及不同部位中桃叶珊瑚苷的含量。结果发现4~9月采集的样品中桃叶珊瑚苷的含量以4月份最高,以后逐渐降低。杜仲各部位桃叶珊瑚苷含量:内皮>叶>枝>栓皮,内皮中的含量明显高于其他部位。  相似文献   

9.
连翘苷对小鼠减肥作用的显微观察   总被引:1,自引:0,他引:1  
为了研究连翘苷对肥胖小鼠脂肪细胞及空肠绒毛表面积的影响,采用高脂饲料建立小鼠肥胖模型,以小鼠脂肪细胞、空肠绒毛表面积大小的变化以及小鼠体重增长率,脂肪系数,全视野内脂肪数目等指标,观察连翘苷的减肥作用。结果显示,连翘苷可以使肥胖小鼠脂肪细胞直径变小,空肠绒毛表面积降低,体重增长率降低,脂肪系数变小,全视野内脂肪细胞数目增加。提示连翘苷对营养性肥胖小鼠有一定的减肥作用。  相似文献   

10.
HPLC法测定感冒退热颗粒中连翘苷的含量   总被引:1,自引:0,他引:1  
采用DiamonsiltmC18(4 6mm× 2 5 0mm ,5 μm)色谱柱 ;以乙腈 水 (2 0∶80 )为流动相 ,流速为 1mL/min ,柱温为 30℃ ,检测波长为 2 77nm ,以外标法用HPLC测定了感冒退热颗粒中连翘苷的含量。连翘苷在0 10 2 9~ 1 6 4 6 4 μg范围内呈线性关系 ,其在制剂中的平均回收率 (n =6 )为 99 5 5 %。  相似文献   

11.
通过对临汾市山区水保封禁治理区域内药用植物的恢复研究,得出:连翘、翅果油树作为该区最主要的两种药用植物,经三年的封禁,其密度恢复分别增加183.8%、8.0%,产量增加9.8%、460.2%;其它药材增加密度为5.6%、产量255.0%,而对其它药用植物的研究可知,耐干旱的、阳性的药用植物恢复好于耐阴,阴性的药用植物,草本药用植物优于灌木、乔木,土石山区的药用植物恢复优于黄土区.封禁治理应是一个长期的植被恢复过程.  相似文献   

12.
In the Oslofjord the amphipods Gammarus oceanicus Segerstråle, 1947 and G. salinus Spooner, 1947 were estimated to live for a maximum of 15 months. All specimens which survived during winter died in spring, mainly in May. A G. oceanicus population living on a freshwater influenced shore contained smaller specimens, had a lower proportion of the female population in breeding condition and probably produced fewer broods than a population living on a fully marine shore. The differences are discussed in relation to environmental factors and the distribution of G. salinus. Gammarus oceanicus possibly was breeding from December to May, some females even in June, resulting in an estimated maximum of three broods from December to May. Gammarus salinus showed two breeding periods, the first from December to May, a few of these females even bred in June, while new females bred from June to October, giving estimated maxima of respectively three (December to May) and five broods. Gammarus salinus females entered a reproductive resting stage in September-October. The sex ratio was mostly female dominated. A shift to male dominance was noted in one population and was related to possible infections. Information from the literature on longevity and breeding periods was compiled and compared to the Oslofjord data.  相似文献   

13.
Cluster bean (Cyamopsis tetragonoloba L.) yield has plateaued due to reduction in rainfall and rise in temperature. Therefore, its production cycle could not get appropriate water and temperature. It becomes important to standardize the sowing time and plant spacing of cluster beans in changing climate scenarios to get higher productivity. Therefore, a field study was conducted in 2019 at the Research area of MNS-University of Agriculture, Multan, Pakistan to evaluate the effect of four sowing times (15th May, 1st June, 15th June, and 1st July) and three plant spacings (10, 12 and 15 cm) on crop growth, yield, and physiological functions of cluster bean genotype BR-2017 under split plot arrangement under randomized complete block design (RCBD) with three replications. The sowing times (15th May, 1st June, 15th June, and 1st July) were placed in the main plot, while plant spacing (10, 12 and 15 cm) was maintained in subplots. The significant effect of sowing time and plant spacing was observed on pod plant−1, pod length, grain yield, and 1000-grain weight. Results showed that 1st June sowing performed better over 15th May, 15th June, and 1st July, while plant spacing 15 cm about in all sowing times showed higher results on growth and yield parameters of cluster bean over plant spacing 10, 12, and 15 cm. The 1st June sowing time at 15 cm plant spacing showed 8.0, 22.7, and 28.5% higher grains pod-1 than 15th May, 15th June, and 1st July sowing, respectively. Maximum grain yield was observed on 1st June in all three spacings (10, 12, and 15 cm). The chord diagram indicates that the crop has received optimum environmental conditions when sown 1st June over other sowing times. In conclusion, 1st June sowing with 15 cm plant spacing could be a good option to achieve maximum productivity of cluster bean under changing climate scenario.  相似文献   

14.
Abstract In western North America, the tick Ixodes pacificus Cooley & Kohls (Acari: Ixodidae) is the primary vector to humans and domestic animals of the disease agents causing Lyme disease and granulocytic ehrlichiosis. We examined the seasonal activity patterns of I. pacificus nymphs over a 4‐year period, including the wet and cold El Niño winter/spring of 1998, in a dry oak/madrone woodland, and for one year in a cooler and moister redwood/tanoak woodland in Mendocino County, California. Linear regressions were used to estimate when nymphal densities first exceeded and then fell below 25, 50 and 75% of the recorded yearly peak densities. In oak/madrone woodland, nymphs typically were active by mid‐March, reached 50% of their yearly peak densities in early to mid‐April, peaked by early May, fell below 50% of their peak densities by early to mid‐June, and were absent by late July to mid‐August. The lengths of the periods with nymphal densities exceeding 50 and 75% of the recorded yearly peaks in oak/madrone woodland were associated positively with rainfall and negatively with maximum air temperatures during April–May. Moreover, nymphal numbers typically reached 50% of their peak 10–15 days later, remained at levels above 50% of the peak 1.3–1.5 times longer, and started declining 4–6 weeks later under cooler, moister climatic conditions (oak/madrone woodland in 1998 and redwood/tanoak woodland in 2000) relative to warmer, drier conditions (oak/madrone woodland in 2000–2001). In oak/madrone woodland, nymphal densities typically started to decline when mean maximum daily air temperatures exceeded 23°C. Nymphal densities were higher in dry oak/madrone relative to moist redwood/tanoak woodland from mid‐March to late May 2000, similar in both habitat types in early June, but higher in redwood/tanoak woodland from late June onwards. We conclude that large‐scale studies of the density of I. pacificus nymphs in California need to consider spatial variation in the length of nymphal activity periods and select temporal sampling regimens that yield representative data for all included habitat types.  相似文献   

15.
河北太行山南段树木年轮指示的167年来相对湿度变化研究   总被引:1,自引:0,他引:1  
王亚军  张永  邵雪梅 《生态学报》2019,39(12):4570-4578
研究建立了河北太行山南段侧柏(Platycladus orientalis)树轮宽度年表,分析树木径向生长对水热变化的响应,构建了研究区167年来相对湿度变化序列。结果表明,侧柏树轮宽度与6月降水显著正相关,与5—7月逐月均温和最高温均显著负相关,侧柏径向生长受到春末夏初水热条件的显著制约。研究区167年来干湿变化明显,明显的干旱期有1876—1877,1900—1901,1904—1912,1918—1921,1926—1930和1933—1935年,湿润期有1871—1873,1882—1884,1888—1890,1893—1895,1953—1956,1971—1972和2002—2003年。5—7月相对湿度变化与旱涝等级负相关达到0.01显著水平。周期分析表明,167年来5—7月相对湿度变化存在2—4年、7.71年和60年左右周期,可能与太平洋活动、太阳活动有一定关联。  相似文献   

16.
Variations in biomass yield, essential oil yield and terpenoid composition in rose-scented geranium (Pelargonium species) in response to seasonal climatic changes were investigated under semiarid tropical climatic conditions. A large number of essential oil samples were collected during different seasonal months (once a month) and daily during the peak summer season months of May and June. They were analysed for terpenoid composition by GC and GC-MS. The crop yielded the lowest values for biomass yield, essential oil yield and essential oil concentration in the summer months of April to June. Evaluation of terpenoid compositions showed minimum concentrations (% of essential oil) of linalool, geraniol and its esters and maximum concentrations of citronellol and its esters during summer months. The percentages of geraniol and its esters were highest during cool winter season months of December and January followed by rainy and autumn season months. Isomenthone, 10-epi-gamma-eudesmol and other minor terpenoid compounds (present in <1% amounts in the essential oil) did not exhibit any definite seasonal trends. Rainy/monsoon (August and September) and autumn (October and November) season months were characterised by high rainfall, cloudy days and short photoperiods. These favourable environmental conditions encouraged crop growth and produced highest biomass yields, essential oil yields and maximum concentration of essential oil in rose-scented geranium plants.  相似文献   

17.
【目的】从药用植物连翘内生真菌中筛选抑菌活性菌株, 并对其主要活性成分进行检测分析。【方法】采用常规组织分离法分离内生真菌, 滤纸片法测定其发酵产物对3种指示细菌的抑菌活性。TLC、HPLC和HPLC-MS检测活性菌株代谢产物中连翘苷成分。根据形态学特征和ITS序列分析鉴定目的菌株。【结果】分离得到的24株内生真菌中抑菌圈直径超过10 mm的菌株, 发酵液组有11株(45.8%), 菌丝体组有19株(79.2%), 活性菌株主要集中在果实内生真菌中, 其中G5、G7和G10表现出较强的抑菌活性。从菌株G10的胞内产物中发现活性成分连翘苷, 将其鉴定为胶孢炭疽菌Colletotrichum gloeosporioides。【结论】连翘内生真菌是天然抗菌活性物质的重要筛选来源。  相似文献   

18.
A crop growth model developed in Canterbury, New Zealand was used to assess the potential of lentil (Lens culinaris) as a grain legume crop in the UK. The model was validated using five sowing dates at Durham (54.77°N, 1.58°W) in 1999. Predicted time to flowering was within 7 days of actual time to flowering and predicted seed yields were within 9% of actual yields. Actual yields ranged from 1.40 to 1.65 t ha‐1. Seed was of high quality. The model was used to predict rate of development and yields of spring and autumn sown lentils at eight sites along a transect from NW Scotland (Stornoway, 58.22°N, 6.32°W) to SE England (East Mailing, 51.28°N, 0.45°E) chosen to encompass important environmental gradients in the UK. In general, for a 1 May sowing with 150 or 250 mm plant available water (PAW) and a 1 October sowing with 150 mm PAW, predicted mean values over the period 1987–95 for maximum crop growth rate, maximum leaf area index, radiation intercepted, total dry matter produced and seed yield were closely positively related to monthly mean values for mean daily air temperature and increased along the transect from NW to SE UK. Time to flowering generally decreased along the transect from NW to SE UK ranging from 28 June to 9 July and from 20 May to 14 June with the May and October sowings respectively. For the 1 May sowing with 250 mm PAW, predicted mean seed yield ranged from 1.00 to 1.90 t ha‐1. For all sites, yield was very stable over the 9 yr period. For the 1 May sowing with 150 mm PAW, predicted mean seed yield ranged from 0.97–1.23 t ha‐1. Yields for the four more southerly sites were more variable at the lower PAW and, in exceptionally dry years, were substantially lower than average. For these sites, autumn sowing increased seed yields in exceptionally dry years and gave similar or greater mean seed yields to spring sowing with 250 mm PAW. For East Mailing, predicted yields for autumn sowing were on average 2.78 t ha‐1. Also, for Stornoway, because of its relatively high overwinter temperatures, the model predicted substantial increases in yield with autumn sowing. It is concluded that lentil has considerable potential as a grain legume crop in the UK.  相似文献   

19.
武汉地区克氏原螯虾繁殖期的研究   总被引:5,自引:0,他引:5  
为探究武汉地区克氏原螯虾(Procambarus clarkii)繁殖期的问题,采用石蜡切片的方法,对武汉地区自然群体中克氏原螯虾雌雄成体的生殖腺进行了周年观察研究。结果表明,武汉地区成年克氏原螯虾的卵母细胞发育不同步,在4~5月以及9~10月的卵巢中都有大量成熟期的卵子,同时也含有少量卵黄发生前期或初期的卵母细胞。6~7月和11月都可见产后恢复期的卵巢,内含少量未产出的正在退化的过熟卵和一些卵黄发生前期或初期的卵母细胞。精巢发育的年周期变化没有卵巢变化的那么明显,但也可以看到,在4~6月和9~10月,含精子细胞和精子的精小管的比例大大增加,而在其他时期,含精原细胞和精母细胞的精小管比例较多。这些结果提示,武汉地区克氏原螯虾一年有两个繁殖高峰期,一个在4~5月,另一个在9~10月。  相似文献   

20.
The activity and diving patterns of four adult Saimaa ringed seals ( Phoca hispida saimensis , a landlocked subspecies living in Lake Saimaa, Finland) were examined during spring, summer, and autumn by the use of VHF-transmitters. Over 17,000 dives were registered. The duration of the dives and diving patterns differed among individuals. The mean duration of dives increased from spring to autumn; e.g. , in one individual the mean dive duration increased from 6 min in June to 10.5 min in October. The haul-out periods of one individual in May to early June made up 46.2% of its total activity budget, but in another individual in July to August the haul-out periods made up only 11% of the budget and the seal was submerged for 80% of the time. Periods of successive long duration dives (>10 min) were observed in three individuals in summer and autumn. The longest dive measured was 23 min. The duration of the periods containing long dives was often over three hours (maximum six hours) and the mean duration of the dives about 15 min. These long duration dives are assumed to be aerobic resting dives. Generally, the dives of the Saimaa ringed seal appear to be of longer duration than previously assumed.  相似文献   

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