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1.
Kassim M  Yusoff KM  Ong G  Sekaran S  Yusof MY  Mansor M 《Fitoterapia》2012,83(6):1054-1059
Malaysian Gelam honey has anti-inflammatory and antibacterial properties, a high antioxidant capacity, and free radical-scavenging activity. Lipopolysaccharide (LPS) stimulates immune cells to sequentially release early pro- and anti-inflammatory cytokines and induces the synthesis of several related enzymes. The aim of this study was to investigate the effect of the intravenous injection of honey in rats with LPS-induced endotoxemia. The results showed that after 4h of treatment, honey reduced cytokine (tumor necrosis factor-α, interleukins 1β, and 10) and NO levels and increased heme oxygenase-1 levels. After 24h, a decrease in cytokines and NO and an increase in HO-1 were seen in all groups, whereas a reduction in HMGB1 occurred only in the honey-treated groups. These results support the further examination of honey as a natural compound for the treatment of a wide range of inflammatory diseases.  相似文献   

2.
Plant defensin is a small, cationic, cysteine-rich broad-spectrum antimicrobial peptide with four or five disulfide bridges and has been shown to be a component of the innate immunity system in plants. In the present study, the defensin gene (TvD1) from Tephrosia villosa was overexpressed in tobacco and characterized. Two high-expression (T1, T26) and one low-expression (T13) plant lines were selected through semi-quantitative RT-PCR and used for bioassays along with non-transgenic controls. The high-expression plant line exhibited strong in vivo anti-fungal and anti-feedant activity against the pathogen Rhizoctonia solani and the first and second instar larvae of the Spodoptera litura (F.), the tobacco cutworm, respectively. The low-expression plant line showed a moderate level of tolerance/resistance in the bioassays. The recombinant peptide (rTvD1) exhibited toxicity to tobacco pollen grains in the germination assay, but transgenic plants produced copious fertile pollen and set capsules with viable seeds. The results of this study demonstrate that the single gene (TvD1) effectively controls both fungal and insect pests and, hence, it can be used for crop transformation.  相似文献   

3.
分别以甲醇、丙酮、水为提取剂,提取山胡椒叶片的次生代谢产物,并测定3种不同提取液的次生代谢产物含量及体外抑菌效果,评价山胡椒的药用价值,为山胡椒的进一步开发利用提供理论依据。实验结果表明,不同提取液中次生代谢产物含量均是黄酮>鞣质>游离蒽醌>皂甙>生物碱;3种提取液的次生代谢产物含量及抑菌活性存在较大差异,不同提取液对枯草芽孢杆菌的抑菌活性要高于大肠杆菌、水可作为山胡椒叶片次生代谢产物的良好提取剂。通径分析表明,影响不同提取液对枯草芽孢杆菌的抑菌活性的次生代谢产物主要是总黄酮和总皂甙,影响提取液对大肠杆菌抑菌活性的次生代谢产物主要是总皂甙。  相似文献   

4.
以苍耳根、茎、叶作为试验材料,以丙酮、80%乙醇、乙酸乙酯、蒸馏水作为提取溶剂,利用滤纸片法研究了苍耳不同器官4种不同溶剂提取液对2种细菌和1种真菌的抑菌活性,结果表明:苍耳各器官的不同溶剂提取液抑菌效果不同。对溶剂来说,苍耳叶丙酮、乙酸乙酯提取液对枯草芽孢杆菌的抑菌圈直径分别达16.32mm、15.66mm,叶的乙酸乙酯提取液对苹果轮纹病菌的抑菌圈直径达15.64mm,4种不同溶剂提取液的总体抑菌活性由大到小依次为丙酮、乙酸乙酯、80%乙醇、蒸馏水;对不同器官来说,苍耳各器官提取液抑菌效果由大到小依次为叶、根、茎,尤以叶的丙酮提取液抑菌效果最佳,乙酸乙酯次之。苍耳叶的丙酮、乙酸乙酯提取液对枯草芽孢杆菌、苹果轮纹病菌均表现为较强的抑菌活性,但对大肠杆菌的抑菌活性较弱。  相似文献   

5.
水合霉素对松材线虫病的影响   总被引:1,自引:0,他引:1  
松材线虫病是松树的一种毁灭性病害。为进一步弄清细菌在病害中的作用,本文筛选了几种对细菌菌株GD1有抑菌活性的抗菌剂,在马尾松(Pinu massomiama水培1a~2a生离体松枝上测定了其对病害发生的影响。结果表明,红霉素和环丙沙星对菌株GD1均有较强的抑菌活性,水合霉素的抑菌活性较弱,叶枯宁、菌毒清、农用链霉素、青霉素钠和氯霉素均没有抑菌活性;离体松枝上的试验显示,水合霉素能减轻混合接种松材线虫(Bursaphelenchus xylophilus)和菌株GD1松枝的病情,而红霉素和环丙沙星无此现象,从而再次证明了细菌在松材线虫病中的重要作用。据此提出了从细菌和松材线虫两方面入手的该病防治策略。  相似文献   

6.
以广东紫珠药材粉末为原料,探讨其不同提取部位的抑菌作用,并筛选其有效部位。对广东紫珠药材用不同极性大小溶剂(石油醚、二氯甲烷、乙酸乙酯、乙醇、70%乙醇、水)回流提取,获得广东紫珠粗提物,用滤纸片法测定其抑菌圈大小(金黄色葡萄球菌、大肠杆菌、奇异变形杆菌、甲型副伤寒沙门氏菌、乙型溶血性链球菌、白色念珠菌),对抑菌活性明显的提取部位进行梯度萃取,并分别测定其抑菌圈大小,得到广东紫珠抑菌有效部位,并测定其有抑菌作用的有效部位的最小抑菌浓度。结果显示广东紫珠70%乙醇提取物对金黄色葡萄球菌、大肠杆菌、奇异变形杆菌、甲型副伤寒沙门氏菌、乙型溶血性链球菌均表现了不同程度的抑菌活性,初步判定为广东紫珠的抑菌活性部位,70%广东紫珠提取物经过萃取后,石油醚萃取物及二氯甲烷萃取物没有抑菌作用,乙酸乙酯萃取物、正丁醇萃取物及剩余的水部分均有不同程度的抑菌作用。70%乙醇广东紫珠提取物通过二氯甲烷萃取除去部分脂溶性杂质,即得到广东紫珠抑菌部位,可以此为基础寻找广东紫珠抑菌活性成分,为后期开发利用提供理论依据。  相似文献   

7.
桑叶总黄酮的提取及其抑菌活性研究   总被引:2,自引:0,他引:2  
以抑菌活性为评价指标,对桑叶总黄酮的提取工艺进行了优化,并对优化条件下得到的粗提物采用不同溶剂进行分级提取和定性分析,测定了各萃取物的总黄酮含量,考察了萃取物对大肠杆菌、金黄色葡萄球菌的抑菌圈直径、最低抑菌浓度,选取抑菌效果最佳的萃取物进行了稳定性实验。结果表明,桑叶总黄酮提取的最佳条件为:温度70℃,乙醇体积分数70%,提取时间4 h,固液比1∶30(g∶mL);抑菌效果最佳的为乙酸乙酯萃取物,且乙酸乙酯部分对温度和紫外线照射的影响均具有良好的稳定性。  相似文献   

8.
Antibacterial spectrum of Hypericum hookerianum.   总被引:1,自引:0,他引:1  
The antibacterial activity of the chloroform, acetone and methanol extracts of Hypericum hookerianum leaves and stems was evaluated. All extracts showed antibacterial activity against six different gram-positive and gram-negative bacteria, the methanol extracts exhibiting the maximum inhibitory activity at 400 microg/ml.  相似文献   

9.
为了探讨不同类型桃果实糖酸代谢的差异性及采后风味劣变的机理,从而为适宜采收成熟度的选择奠定理论基础,以不同成熟度的‘沪油018’油桃、‘湖景蜜露’水蜜桃和‘玉露’蟠桃为试材,对其果实在采后糖酸代谢的规律和差异性进行了研究。结果表明:1采收时,七、八、九成熟的‘沪油018’其果实中的蔗糖含量间无显著性差异,八成熟‘湖景蜜露’水蜜桃果实中的蔗糖含量显著高于其七成熟果实,七成熟‘玉露’蟠桃果实中的蔗糖和山梨醇含量均显著高于其八成熟果实;‘玉露’蟠桃果实中的蔗糖含量(82.8~91.49 mg·g~(-1))显著‘湖景蜜露’水蜜桃(77~87 mg·g~(-1))‘沪油018’(55~60 mg·g~(-1));七、八成熟‘沪油018’和‘湖景蜜露’水蜜桃果实中的苹果酸和总酸含量间的差异均不显著,七成熟‘玉露’蟠桃果实中各游离酸和总酸含量均显著高于(P≤0.05)其八成熟果实;‘玉露’蟠桃和‘沪油018’果实中的苹果酸含量均显著高于‘湖景蜜露’水蜜桃。2室温贮藏期间,3种类型桃果实中蔗糖和总糖含量的变化均较缓和;七、八成熟‘玉露’蟠桃和‘沪油018’果实中的苹果酸和总酸含量均呈上升趋势,七成熟‘湖景蜜露’水蜜桃果实中的奎宁酸和苹果酸含量均呈急剧下降的趋势。3低温冷藏下,七、八成熟果实中糖的合成速率均低于室温贮藏的果实,九成熟果实中的果糖和葡萄糖含量均已呈降解趋势,其甜度也有一定程度的降低;七、八成熟‘湖景蜜露’果实中各游离酸和总酸含量均呈急剧下降趋势,而‘沪油018’和‘玉露’蟠桃的变化均较缓和。综合分析结果表明:不同类型桃果实的糖酸组分及其代谢存在一定的差异,‘湖景蜜露’水蜜桃风味劣变快于其他两个品种;室温和低温贮藏期间,其果糖组分及含量的变化均缓和,而其果酸组分及含量的变化却均剧烈。文中因此建议,以酸代谢为果实低温冷藏研究的主要方向,以酸降解峰点来界定果实的安全贮藏期。  相似文献   

10.
《Fitoterapia》1999,70(5):523-525
2-Hydroxyheptane-3,5-dione (1) was obtained from the petrol-soluble fraction (PE) of the ethanol extract of Potamogeton nodosus. Biological screening of PE revealed antibacterial activity and cytotoxicity. Compound 1 showed only antibacterial activity.  相似文献   

11.
Investigations on longevity and fertility of Megastigmus bipunctatus Swederus (Hym., Chalc., Torymidae)Investigations on the influence of different climatic and nutritional factors on longevity and fertility of adult femaleMegastigmus bipunctatus showed that differences in relative humidity had little effect. In higher temperatures longevity and fertility were reduced; the number of undeveloped eggs was reduced more than the number of mature eggs. Food formulas containing protein in the form of chicken egg albumen had a negative effect on longevity and fertility when compared with data fromM. bipunctatus femals kept without food and water. An increase of both, life span and number of eggs, was observed after giving distilled water, aqueous honey solution or aqueous honey solution enriched with vitamin mixture. A maximum increase was obtained with femals living only on honey solution.  相似文献   

12.
The aerial parts of Anvillea radiata yielded a new germacranolide, 8alpha,9alpha-epoxyparthenolide (3), together with two known compounds, 9alpha-hydroxyparthenolide (1) and parthenolid-9-one (2). The structures of the compounds were elucidated from IR, HRMS, 1H and 13C-NMR, COSY, HETCOR, HMBC and HOHAHA spectral data. The major component 1 was tested for its cytotoxicity and antibacterial activity.  相似文献   

13.
为给鸭儿芹的综合利用提供科学依据,以鸭儿芹茎、叶为原料,采用水蒸气蒸馏法提取鸭儿芹精油,利用气相色谱-质谱联用技术(GC-MS)对鸭儿芹精油成分进行了分析,利用DPPH、ABTS自由基清除能力试验与FRAP试验及打孔法抑菌试验对其精油的抗氧化抗菌活性进行了分析。结果表明:(1)精油成分方面,从鸭儿芹精油中共分离出32个峰,占总离子峰的93.75%,共鉴定出30种化合物,其主要成分分别为α-芹子烯(42.01%)、β-芹子烯(19.86%)、(Z)-β-金合欢烯(12.76%)、镰叶芹醇(4.16%)、α-没药醇(3.93%)等;(2)抗氧化能力方面,当鸭儿芹精油浓度由19μg/m L上升到38μg/m L时,DPPH反应液中Trolox的当量由0.003μmol上升到0.007μmol,ABTS反应液中Trolox的当量由0.069μmol上升到0.074μmol,FRAP反应液中Trolox的当量由0.225μmol上升到0.280μmol,当精油浓度在一定范围内,其DPPH清除能力、ABTS自由基清除能力及铁离子还原抗氧化能力与其浓度间均呈量效关系,且均呈正相关效应,表明鸭儿芹精油具有良好的抗氧化能力;(3)抗菌活性方面,当鸭儿芹精油浓度为1 280 mg/m L时,金黄色葡萄球菌的抑菌圈直径可达7.05 mm,表现出一定的抑菌活性,且其对金黄色葡萄球菌的抑菌效果显著优于其对大肠杆菌的抑菌效果。  相似文献   

14.
The effects of fire retardant application at varying rates on surface-dwelling ants in heathland communities were assessed over a 1-year period from March 2001 to March 2002. The study was conducted at two sites, one in East Gippsland at Marlo and the other in the Grampians region of south-west Victoria where a total across both sites of 6407 specimens representing 18 ant species contained in 5400 pitfall trap samples were collected. It was concluded that despite retardant application, no significant effect was observed within the major ant species Rhytidoponera metallica (Smith) and Pheidole sp. at both sites. These species appear to form a stable component of the heathland ant community. However, significant decreases in activity were observed for Camponotus terebrans (Lowne) at the Grampians site and Paratrechina sp. at the Marlo site. Evidence suggests that retardant application when combined with prevailing suitable climatic conditions, leads to foliage mortality, litter accumulation and weed invasion, leading to potential creation of habitat less suitable for activity of these species. When assessed in terms of taxon richness and community evenness, ant species were unaffected at the Grampians, while at Marlo, community evenness was affected due to the smaller number of individuals collected in the medium retardant treatment. When assessed by their functional groupings, the Subordinate Camponotini showed significantly reduced activity on the retardant treated sites at the Grampians directly as a result of C. terebrans activity. Further study is required to determine the combined effects of fire and retardant on ant species, as well as any longer-term effects past 1 year.  相似文献   

15.
从本研究室保藏的一株来自于凯菲尔粒的嗜酸乳杆菌培养基质中分离出具有抑菌活性的蛋白组分——细菌素,对该嗜酸乳杆菌所产生的细菌素的分离方法及表面活性剂对其抑菌活性的影响作用进行了研究。结果表明,嗜酸乳杆菌在添加了油酸的MRS培养基中培养16h后达到产细菌素高峰;对细菌素分离纯化研究包括三个步骤:硫酸铵沉淀、离子交换色谱(IEC)和疏水作用色谱(HIC)。不同类型的表面活性剂对细菌素的抑菌活性具有不同的影响。  相似文献   

16.
利用含氮和含卤素试剂对银杏叶聚戊烯醇末端羟基进行含氮和含卤素的衍生化改性,结果得到5种衍生物,分别为聚戊烯基邻苯二甲酰亚胺(GPH)、氨基聚戊烯醇(GAM)、聚戊烯基季铵盐(GAS)、聚戊烯基三氟乙酰(GTF)和聚戊烯基氯乙酰(GCH),并用~1H NMR分别表征并证实了产物结构。通过比较产物抑菌圈直径和最小抑质量浓度(MIC)来筛选出抗菌作用较强的衍生物,结果显示:GAS对于大肠杆菌和金黄色葡萄球菌的抗菌活性均为最高,其抑菌圈为19.1~19.8 mm,MIC均为31.3 mg/L。同时研究了GAS在亚抑菌质量浓度下(15.6 mg/L)对大肠杆菌和金黄色葡萄球菌的杀菌曲线,结果显示:GAS对大肠杆菌和金黄色葡萄球菌在48 h内具有一定抗菌性;在前8 h内,GAS对于大肠杆菌和金黄色葡萄球菌的杀菌作用较强,致使菌群数量迅速下降;8 h以后,两种菌群都有不同程度的再生,抑菌活性减弱。  相似文献   

17.
高速公路两侧水蜜桃重金属污染调查   总被引:1,自引:0,他引:1  
经调查测定,锡宜高速公路两侧不同距离水蜜桃鲜果中砷、汞、铅、铬、镉等重金属含量分别不高于0.018mg/kg、0.001 8 mg/kg、0.11 mg/kg、0.022 mg/kg、0.008 mg/kg,满足无公害水果相应重金属含量分别低于0.5 mg/kg、0.01 mg/kg、0.2 mg/kg、0.5 mg/kg、0.03 mg/kg的要求,证实锡宜高速公路两侧水蜜桃鲜果中重金属含量符合无公害农产品标准.  相似文献   

18.
Three new carbazole alkaloids, harmandianamines A-C (1-3), together with fifteen known compounds (4-18) were isolated from the twigs of Clausena harmandiana. The structures were elucidated by spectroscopic methods, including UV, IR, NMR, and MS. The antibacterial activity against Escherichia coli TISTR 780, Salmonella typhimurium TISTR 292, Staphylococcus aureus TISTR 1466 and methicillin-resistant S. aureus (MRSA) SK1 of some isolated compounds was also evaluated. Compound 6 exhibited significant antibacterial activity against MRSA SK1 with an MIC value of 0.25 μg/mL which higher than that of standard drug, vancomycin (MIC value=1 μg/mL) whereas compounds 14 and 5 showed strong activity with MIC values of 4 and 8 μg/mL, respectively. Only compound 14 showed strong antibacterial activity against S. aureus TISTR 1466 with an MIC value of 4 μg/mL.  相似文献   

19.
Nine samples of Glycyrrhiza glabra were collected in various sites of Calabria, Italy, with the aim to determine the variability in the confront of active constituents and in antibacterial and antifungal activities of the extracts. The samples showed remarkable differences in chemical composition and biological activity.  相似文献   

20.
Antimicrobial activity of Symplocos cochinensis.   总被引:1,自引:0,他引:1  
The methanol extracts of leaves, root and stem barks of Symplocos cochinchinensis and their fractions obtained by partition (petrol, dichloromethane, ethyl acetate) were screened for antimicrobial activity. All the crude extracts and fractions showed a broad spectrum of antibacterial activity, that was enhanced on fractionation. None of them showed activity against the tested moulds.  相似文献   

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