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桑叶不同极性溶剂提取物的总多酚含量与抑菌活性 总被引:2,自引:0,他引:2
用不同极性溶剂萃取桑叶粉中的活性物质,分别获得乙酸乙酯提取物、正丁醇提取物和水提取物。采用琼脂打孔扩散法评价桑叶各极性溶剂提取物的抑菌效果,结果表明桑叶不同极性溶剂提取物对供试革兰阳性菌和革兰阴性菌均有一定的抑制作用,其中乙酸乙酯提取物的抑菌活性显著高于其它溶剂提取物,对大肠杆菌(Escherichia coli)的最低抑菌浓度为6.3mg/mL,对金黄色葡萄球菌(Staphyloccocus aureus)、枯草芽孢杆菌(Bacillus subtilis)、沙门氏菌(Salmonella sp.)的最低抑菌浓度均为12.5 mg/mL。测定乙酸乙酯提取物中的总多酚质量比为(11.91±0.67)mg/g,显著高于其它溶剂提取物,表明桑叶不同极性溶剂提取物的抑菌活性与其总多酚的含量成显著剂量效应关系(P<0.05)。 相似文献
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青枯劳尔氏菌(Ralstonia solanacearum)是引发桑青枯病的病原细菌。为了寻求防治桑青枯病的天然药剂,以工业提取黄酮化合物剩余的蜂胶渣为原料,经甲醇、乙醇、乙酸乙酯、氯仿及石油醚等溶剂分级浸提获得除蜡蜂胶渣提取物。通过比浊法测试不同极性溶剂提取物对青枯劳尔氏菌5个生理小种菌株均有一定的抑制作用(抑菌率8.36%~99.73%),其中乙醇提取物的抑菌活性显著高于其他溶剂的提取物(P0.05)。0.1 mg/m L除蜡蜂胶渣乙醇提取物对青枯劳尔氏菌RS-5菌株的抑制率达91.61%±4.75%,最低抑菌浓度为0.25 mg/m L,最小杀菌浓度为4 mg/m L,用扫描电子显微镜观察到部分病原细菌发生变形和细胞壁破损,用平板法监测到菌体的泳动性能受到不同程度抑制。基于负离子全扫描模式的LC-MS谱图鉴定除蜡蜂胶渣中主要含有咖啡酸及其酯类化合物(包括咖啡酸丙酯、咖啡酸丁酯、咖啡酸苯乙酯及咖啡酸戊酯),采用选择性反应监测模式外标法检测出其中所含咖啡酸和咖啡酸苯乙酯的质量比为1∶3.3。研究结果表明,除蜡蜂胶渣的乙醇提取物对青枯劳尔氏菌具有良好的抑制活性,发挥抑菌活性的主要成分可能是咖啡酸及其酯类衍生物,该提取物有进一步开发为天然来源的桑青枯病防控药剂的潜力。 相似文献
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《黑龙江畜牧兽医》2017,(21)
为了研究番石榴叶提取物的体外抑菌和抗氧化作用,试验采用试管倍比稀释法测定番石榴叶提取物对猪大肠杆菌和金黄色葡萄球菌的抑菌效果,采用总抗氧化检测试剂盒和紫外-可见分光光度法分别测定番石榴叶提取物的抗氧化效果及其总黄酮和总酚的含量。结果表明:番石榴叶不同极性提取物对猪大肠杆菌的抑菌效果差异不明显,番石榴叶石油醚提取物对猪金黄色葡萄球菌的抑菌效果较好(0.195 mg/mL);总抗氧化活性由大到小依次是番石榴叶正丁醇提取物、乙酸乙酯提取物和石油醚提取物。番石榴叶正丁醇提取物总酚含量最高,为215.55 mg/g;番石榴叶乙酸乙酯提取物总黄酮含量最高,为42.59 mg/g。说明番石榴叶提取物具有抑菌作用,提取物中总酚含量越高其抗氧化效果越好。 相似文献
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建立了蜂胶中的酚酸和黄酮的高效液相色谱质谱联用(HPLC-MS)定量方法。不同来源的蜂胶样品置于乙醇中,在70℃的条件下提取2h,提取物通过5μmC18对称性的250mm×4.6mm柱子分离。通过线性梯度洗脱方法分离,二极管阵列检测器(DAD)设置在200~450nm,MS测定范围设在100~1000Da。其中的大部分化合物主要是通过与标准品的HPLC色谱图的保留时间(RT)和紫外光谱对照进行定性的。没有标准品的,通过色谱的在线的紫外数据和质谱进行确认。欧洲、中国和阿根廷蜂胶的主要特点是含有黄酮和酚酸,主要成分为柯因(2~4%),松属素(2~4%),短叶松素乙酸酯(1.6~3%)及高良姜素(1~2%)。巴西蜂胶主要含有阿替匹林C、咖啡酰奎尼酸和黄酮类物质。如果考虑将黄酮的总含量纳入质量标准,我们认为低于11%的黄酮含量的蜂胶是次品,黄酮含量在11~14%为可以接受的,黄酮含量在14~17%的属于质量好的,高于17%属于高质量的。LC-DAD-MS分析方法可以用于蜂胶的化学成分的分析和商业上的蜂胶制品的质量鉴定。 相似文献
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试验旨在研究不同溶剂对蒙早苦荬菜活性物质提取的影响。试验以蒙早苦荬菜为原料,采用超声波辅助提取法,使用5种不同溶剂提取蒙早苦荬菜根、茎、叶进行总酚和总黄酮,测定提取液的抗氧化活性,评价不同溶剂提取物抗氧化能力与活性物质的相关性。结果显示,不同极性溶剂对不同部位的提取效果不同,叶的60%乙醇提取物总黄酮和总酚含量均为最高,分别为10.22、10.69 mg/g;根的乙醇(99.7%)提取物总黄酮含量最高(7.65 mg/g),甲醇提取物总酚含量最高(3.92 mg/g);茎的水提物总黄酮含量最高(6.89 mg/g),60%乙醇提取物总酚含量最高(3.36 mg/g)。研究表明,蒙早苦荬菜中活性物质的含量与其抗氧化性间呈良好的量效关系。蒙早苦荬菜各部位总黄酮和总酚的提取量排序为叶>根>茎,60%乙醇溶液是提取蒙早苦荬菜总黄酮和总酚的最佳溶剂。 相似文献
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分析了白三叶(Trifolium repens)种子经卫星搭载后,当代植株与光合作用相关的几种特性,包括叶片叶绿素含量、光合特性及叶绿体的超微结构。结果表明,卫星搭载当代植株叶片的叶绿素a和叶绿素总量显著下降(P<0.05);在13:00-15:00,白三叶的净光合速率(Pn)、气孔导度(Cond)和蒸腾速率(Tr)显著低于对照(P<0.05);与对照相比,卫星搭载当代植株叶片叶绿体扭曲,淀粉粒多,且大小不一,甚至有的无序堆满整个叶绿体,嗜锇颗粒在叶绿体中分布不集中,有的分布的多,有的很少,线粒体有明显的溢裂现象。基粒片层减少,直径加大。 相似文献
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NaHCO3胁迫对大叶紫花苜蓿生理特征的影响 总被引:9,自引:3,他引:6
采用砂基培养方法,研究了不同浓度的NaHCO3对大叶紫花苜蓿Medicago sativa叶片叶绿素、脯氨酸、丙二醛含量以及细胞膜透性的影响.结果表明,随着NaHCO3浓度的增大,脯氨酸含量、丙二醛含量及细胞膜透性逐渐增大;在NaHCO3浓度为50 mmol/L时叶绿素a和b的含量最大,浓度在50~200 mmol/L时叶绿素a和b的含量逐渐降低,且叶绿素a降低的趋势比较缓慢.说明大叶紫花苜蓿对低浓度的NaHCO3胁迫有一定的适应能力. 相似文献
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A total of 105 growing pigs (24.91 ± 1.06 kg) were used in a 6‐week trial to investigate the effects of including Saccharomyces cerevisiae cell wall extract and poplar propolis ethanol extract (SPE) in the diet on growth performance, digestibility, blood profiles, fecal microbiota and fecal noxious gas emissions. Pigs were randomly allocated to one of three dietary treatments (seven pens/treatment, five pigs/pen) according to initial body weight and sex (two gilts and three barrows). Treatments consisted of a corn soybean meal basal diet supplemented with 0, 0.05 or 0.10% SPE. There was a significant linear improvement (P < 0.05) in average daily gain, gain/feed, the apparent total tract digestibility of dry matter, nitrogen, and gross energy, blood lymphocyte percentage, immunoglobulin G concentration, fecal Escherichia coli and Lactobacillus counts as well as fecal NH3 and H2S emissions associated with the inclusion of SPE in the diet. Average daily feed intake, red blood cells and white blood cells concentration were not significantly (P > 0.05) affected by SPE supplementation in the diets. In conclusion, results indicate that dietary SPE supplementation can improve growth performance, digestibility and fecal microbiota, and decrease fecal gas emissions in growing pigs. 相似文献
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Adjuvant effect of green propolis on humoral immune response of bovines immunized with bovine herpesvirus type 5 总被引:1,自引:0,他引:1
Fischer G Cleff MB Dummer LA Paulino N Paulino AS de Oliveira Vilela C Campos FS Storch T D'Avila Vargas G de Oliveira Hübner S Vidor T 《Veterinary immunology and immunopathology》2007,116(1-2):79-84
Despite recent technological advances in vaccine production, most vaccines depend on the association with adjuvant substances. In this study, propolis, which has been attracting the attention of researchers due to its bioactive properties, was evaluated as an immunological adjuvant. The association of 40mg/dose of an ethanolic extract of green propolis with an inactivated oil vaccine against bovine herpesvirus type 5 (BoHV-5), resulted in a significant increase (P<0.01) in the neutralizing antibody levels, comparing to the bovines that received the same vaccine without propolis. Besides, propolis increased the percentage of animals with high antibody titers (above 32). Phenolic compounds such as artepillin C (3,5-diprenyl-4-hydroxycinnamic acid) and the derivatives of cinnamic acid besides other flavonoid substances were abundant in the propolis extract used, and they could be the main substances with adjuvant action. The effect of the green propolis extract on the humoral immune response can be exploited in the development of new vaccines. 相似文献
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本文通过鸡胚接种的方法就蜂胶乙醇浸出物对NDV的灭活作用进行了试验观察,结果表明常温下3min,1mg/ml的47.5%乙醇稀释液对ND克隆-30具有灭活作用。含蜂胶乙醇浸出物0.1mg/ml的95%乙醇稀释液、含蜂胶乙醇浸出物10mg/ml的47.5%乙醇稀释液、含蜂胶乙醇浸出物10mg/ml的生理盐水稀释液;37℃3min,含蜂胶乙醇浸出物0.1mg/ml的95%乙醇稀释液、含蜂胶乙醇浸出物0.1mg/ml的47.5%乙醇稀释液、含蜂胶乙醇浸出物10mg/ml的生理盐水稀释液均对ND克隆-30具有完全灭活作用。 相似文献
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Gressler LT Da Silva AS Machado G Rosa LD Dorneles F Gressler LT Oliveira MS Zanette RA de Vargas AC Monteiro SG 《Research in veterinary science》2012,93(3):1314-1317
Current therapy of Trypanosoma evansi infections is not effective for the vast majority of animals with relapsing parasitemia and clinical signs. Recently, attention is being focused on the antiparasitic activity of propolis. This study evaluated the susceptibility of T. evansi to propolis extract in vitro and in vivo. A dose-dependent trypanocidal activity of propolis extract was observed in vitro. All trypomastigotes were killed 1h after incubation with 10μgmL(-1) of the extract. In vivo, the concentrations of 100, 200, 300 and 400mgkg(-1) administered orally for 10 consecutive days showed no curative effect, and the rats died from the disease. However, rats treated with the two highest concentrations of propolis extract showed higher longevity than the other groups. Based on these data, we concluded that T. evansi is susceptible to propolis in vitro. Despite the lack of curative efficacy observed in vivo at the concentrations tested, the propolis extract can prolong life in rats infected with the protozoan. 相似文献