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1.
采用活性跟踪法从银胶菊中分离获得抗病毒活性物质,经质谱和核磁共振分析,确定该物质为小白菊内酯.采用半叶枯斑法和叶圆盘法测定了其对烟草花叶病毒(Tobacco mosaic virus,TMV)的抑制效果,结果表明:0.2 mg/mL的小白菊内酯在混合接种和药液浸泡两种处理中均表现出较好的体外抑制TMV活性,其抑制率分别为69.0%和72.1%;在离体条件下对烟草叶圆盘中的烟草花叶病毒复制也具有良好的抑制效果,抑制率为72.3%.  相似文献   

2.
本文对粘细菌AHB103-1的次级代谢产物A组分的抗肿瘤活性和作用机制进行了初步的探讨。采用MTT方法研究了它对HepG2、MDA-MB-231、293T和B16四种肿瘤细胞的作用浓度和作用时间,并与临床上应用的几种抗肿瘤药物对HepG2细胞的作用效果进行了比较;利用荧光显微镜和扫描电镜观察研究了它对HepG2细胞的作用机制。结果表明:A组分的抗癌活性比泰素低,却高于表柔比星、依立替康和奥沙利铂。当样品浓度≥15μg/mL时,对各种肿瘤细胞株的抑制率均达到90%以上。随着样品浓度的降低,对各细胞株的抑制率均表现下降趋势。当样品浓度为30μg/mL时,对四种细胞株作用时间选择24 h即有理想效果。当样品浓度为1.88μg/mL时,对B16、293T和HepG2细胞,作用时间选择48 h较好;而对MDA-MB-231,作用时间选择72 h较好。荧光显微镜和扫描电镜观察的结果分别从形态学上证明了A组分具有引起HepG2细胞凋亡的活性。  相似文献   

3.
本文初步研究了松茸多糖TMSP-5亚组分Ⅱ的美白作用机理。采用酪氨酸酶抑制实验、细胞水平黑色素测定实验来综合评价TMSP-5亚组分Ⅱ的美白功效;选定MITF、POMC和TYR三个靶基因作为研究对象,通过实时定量PCR实验,进一步阐明TMSP-5亚组分Ⅱ的美白作用靶点。结果显示,TMSP-5亚组分Ⅱ对酪氨酸酶具有一定的抑制作用,125μg/m L时酪氨酸酶抑制率为56.5%;不同浓度(3、30、300μg/m L)的TMSP-5亚组分Ⅱ样品能成剂量依赖的方式抑制B16细胞内黑色素水平,当浓度为300μg/m L时,TMSP-5亚组分Ⅱ样品能够减少黑色素的含量,且优于熊果苷;TMSP-5亚组分Ⅱ对MITF、POMC、TYR的表达水平均起下调作用,从而影响了黑素的形成。结果表明,TMSP-5亚组分Ⅱ样品具有一定的美白功效。TMSP-5亚组分Ⅱ样品对酪氨酸酶生成的重要基因和主要影响因子的基因水平的表达起到抑制作用,从而减少酪氨酸酶的量。  相似文献   

4.
以水稻(Oryza sativa)等5种植物和水稻稻瘟病(Magnaporthe grisea)等6种植物病原真菌为试验对象,测定了碎米莎草(Cyperus iria)茎总生物碱对植物和病原菌的生物活性.结果表明,250~4000 μg mL-1的总生物碱对水稻种子的萌发无显著影响,对千金子(Leptochloa chinensis)幼苗的苗高有显著抑制作用.4000μmL-1的总生物碱对烟草(Nicotiana tabacum)、鳢肠(Eclipta prostrate)和车前草(Plantago asiatica)种子的萌发、烟草幼苗的苗高以及水稻、烟草和鳢肠幼苗的鲜重有显著抑制作用,相对较低浓度总生物碱对千金子种子萌发、千金子和车前草幼苗的鲜重以及5种植物幼苗的根长和苗高(烟草幼苗的苗高除外)有显著抑制作用.25~400 μg mL-1的碎米莎草茎总生物碱对小麦赤霉病菌(Fusarium gramblearum)的生长无显著影响,而对苹果轮纹病菌(Physalospora piricola)的生长有显著抑制作用,100~400μg mL-1的总生物碱对稻瘟病菌、油菜菌核病菌(Sclerotinia sclerotiovum)和番茄早疫病菌(Alternaria solani)的生长有显著抑制作用,200~400 μg mL-1的总生物碱对杨树溃疡病菌(Dothiorella gregaria)的生长有显著抑制作用,400μg mL-1的总生物碱对上述病原真菌的抑菌率分别为8.20%、74.87%、40.93%、60.91%、52.70%和16.28%.  相似文献   

5.
目的:建立婴幼儿配方奶粉中3-氯丙醇酯的气相色谱—质谱联用(GC-MS)测定方法,并对部分市售婴幼儿配方奶粉中3-氯丙醇酯的含量进行调查。方法:用乙醚+石油醚(1∶1)提取奶粉样品中脂肪,以1 mL甲醇钠甲醇溶液(0.25 mol/L)将脂肪中的3-氯丙醇酯(3-MCPD酯)水解成3-氯丙醇(3-MCPD)并用硅藻土小柱净化后,经七氟丁酰基咪唑衍生,再用选择离子监测的气相色谱—质谱联用法测定,采用内标法定量。结果:3-MCPD酯在250~5 000 μg/kg范围内线性良好(r>0.999),3个浓度水平下加标回收率为71.5%~99.6%,相对标准偏差为2.3%~6.0%。20份奶粉样品中,检出率65%,含量为0.26~0.97 mg/kg脂肪、0.042~0.22 mg/kg样品。不同阶段统计婴幼儿配方奶粉平均暴露量,一阶段 3.32 μg/(kg·bw)、二阶段 2.42 μg/(kg·bw)、三阶段 2.72 μg/(kg·bw)、四阶段 0.23 μg/(kg·bw)。结论:该方法灵敏度高、定量准确度,适合婴幼儿配方奶粉中3-氯丙醇酯的检测。  相似文献   

6.
由一株链霉菌产生的核苷N970 5是肽酰胞嘧啶核苷衍生物 ,具有广谱抗生活性。N970 5能够抑制疱疹病毒I型 (HSV I)对Vero细胞、烟草花叶病毒 (TMV)对烟叶细胞的病理损伤作用 ;对四种水稻病原真菌和一种烟草病原真菌有较强的抑制生长作用 ;还对腐生线虫 (P .redivivus)及松材线虫 (B .xylophilus)有杀伤作用。  相似文献   

7.
摘要:【目的】通过对2株活性海洋真菌发酵产物提取物抑制烟草花叶病毒和抗肿瘤活性进行研究,为进一步得到活性纯品化合物作为抗病毒及抗肿瘤的先导化合物奠定基础。【方法】菌株发酵产物的粗提物是通过甲醇浸取并在真空条件下蒸干得到的。粗提物中溶于水的部分为水溶性部分,不溶于水的部分为脂溶性部分。通过间接酶联免疫法检测样品抑制烟草花叶病毒的活性,通过四甲基偶氮唑盐微量酶反应比色法(MTT法)检测样品抗肿瘤活性,通过形态及ITS rDNA序列法进行菌株鉴定。【结果】两株海洋真菌抑制烟草花叶病毒活性和抗肿瘤的活性均较高。分子鉴定结果显示,两株真菌分别与Penicillium oxalicum 和 Neosartorya fischeri 的同源性极高。菌株0312F1发酵液的水溶性部分具有抗病毒及抗肿瘤活性,菌株1008F1发酵液的脂溶性部分具有抑制烟草花叶病毒活性,而水溶性部分具有抗肿瘤活性。【结论】菌株0312F1和菌株1008F1发酵液的提取物抑制烟草花叶病毒的活性部位不同,而抗肿瘤活性部位相同。菌株0312F1发酵液提取物的水溶性活性部位对肝癌细胞BEL-7404的抑制效果比对胃癌细胞SGC-7901的抑制效果明显,而菌株1008F1发酵液提取物的水溶性活性部位对胃癌细胞SGC-7901的抑制效果比对肝癌细胞BEL-7404的抑制效果明显。  相似文献   

8.
一种食用菌提取物y3对烟草花叶病毒的钝化作用及其机制   总被引:6,自引:0,他引:6  
测定了从食用菌毛头鬼伞(Coprinus comatus)中提纯的y3蛋白对烟草花叶病毒(Tobacco mosaic virus,TMV)的钝化作用,结果表明y3对TMV有较强的体外钝化作用,在心叶烟枯斑寄主上对TMV的抑制中浓度约为2.0μg/mL;y3在pH9.0时较稳定;TMV与y3混合后用RNase处理,测得侵染率为61.74%,比未用RNase处理的对照降低了38.26%,说明y3具有一定的体外脱衣壳作用;另外电镜观察发现y3可使部分TMV粒体发生裂解,变短.  相似文献   

9.
采用菌丝生长抑制法,测定了小桐子枝叶6种不同溶剂提取物对小麦赤霉病菌、稻瘟病菌、烟草疫霉菌和辣椒疫霉菌的抑制作用,从中筛选出抑制作用最强的粗提物进行进一步的活性组分分离和抑菌活性测定。结果表明小桐子枝叶的乙醇提取物对4种植物病原菌抑制活性最高,在浓度为0.8 g·L-1时,小桐子枝叶的乙醇提取物对小麦赤霉病菌、稻瘟病菌、烟草疫霉菌、辣椒疫霉菌菌丝生长抑制率分别为:87.1%、90.3%、86.4%、77.9%,其抗菌活性与农药世高均无显著差异;在小桐子枝叶乙醇提取物的不同溶剂萃取物对稻瘟病菌和烟草疫霉病菌进行生物活性追踪测试中发现,石油醚和水萃取物都具有较好的活性,当浓度为0.8 g·L-1时,石油醚和水萃取物对两种病菌抑制率都达50%以上。表明小桐子枝叶含有丰富的抗植物病原真菌活性物质,且主要存在于小桐子枝叶乙醇提取物的石油醚相和水相中。  相似文献   

10.
为了探讨新疆胀果甘草总黄酮(general flavonoids,GFs)对宫颈癌细胞的细胞毒活性,自制备胀果甘草GFs,通过离子阱喷雾式质谱技术分析,建立GFs组分的指纹图谱;并且对SiHa宫颈癌细胞进行GFs药物干预,应用MTT法和流式细胞技术分别鉴定细胞活力和细胞凋亡率。获得了新疆胀果甘草GFs组分的特征性指纹图谱,提取物中GFs含量可达35.40%;发现在0~500μg/mL GFs浓度范围内,GFs药物干预引起细胞活力梯度性下降,其MTT法检出的最低值为12%;在0~1000μg/mL GFs浓度范围内,GFs诱导的细胞凋亡率呈现梯度性上升趋势,其流式细胞仪检出的最高值为78%。结果表明新疆胀果甘草GFs具有较强的细胞毒活性,能够抑制宫颈癌细胞生长与活力,并诱导细胞凋亡。  相似文献   

11.
Some chemical and physical properties of agarose (AG) and agaropectin (AP) isolated from agar of various red seaweeds were studied. The two components were isolated by acrinol. Methanol containing sodium iodide was superior to the mixed solvent of ethanol and acetone (1:1) as solvent for removing acrinol. Greater value of the ratio of intrinsic viscosity of both AG and AP in the solution of 0.1 m sodium chloride against that in the mixed solution of 4 m urea and 0.001 m sodium thiocyanate made water holding capacity greater except sample whose molecular weight is very small. Water holding capacity of AG was decreased with increasing ratio of d-galactose plus 6-O-methyl-d-galactose against 3,6-anhydro-l-galactose, and with lower liquefying temperature of gel. In the case of AP, however, these relations were not always distinct.  相似文献   

12.
A strain of Penicillium corylophilum isolated from Brazilian soil sample was submitted to different culture conditions to investigate the production of secondary metabolites with antimicrobial activity. The largest number of conidia was obtained after 5 days of incubation in oat medium and the highest level of antimicrobial activity was produced when the fungus culture was developed in the Czapek medium. The activity against Staphylococcus aureus was found only in the chloroform extract from Czapek culture broth, which also showed activity against Micrococcus luteus. Fumiquinozoline F was isolated from the active chloroform extract by using chromatographic methods. The minimal inhibitory concentration (MIC) values for M. luteus and S. aureus were 99 μg/mL and 137 μg/mL, respectively.  相似文献   

13.
The Indian sarsaparilla (Hemidesmus indicus) is a commonly used plant in Indian traditional medicine of Ayurveda for the preparation of various non-alcoholic beverages. However, limited studies are available on the essential oil of H. indicus roots (HRO); therefore, the study evaluated the antioxidant, anti-inflammatory and antidiabetic activities of H. indicus root essential oil as well as insecticide potential against the common pests of stored food materials (Sitophilus oryzae, Callosobruchus maculatus and Tribolium castaneum). The repellant efficacy of HRO was found to be high against S. oryzae (8.21 ± 0.55 μg/mL). Likewise, the fumigant potential was also observed for HRO against these pests; the higher activities were observed against S. oryzae and C. maculatus (32.46 ± 1.42 and 35.18 ± 1.62 μg/L). Besides, the essential oil was also found to be active as a contact poison, however, against all the three pests, the toxicity was above 100 μg/mm3, being the highest against C. maculatus (122.8 ± 3.57 μg/mm3). To analyze the possible effect of the essential oil on grains, the different grains were allowed to germinate and compared to that of normal; thus, the non-toxic nature of HRO against the stored products is also confirmed. The essential oil shown to have DPPH hydrogen peroxide and ABTS radical scavenging, nitric oxide scavenging potential, and inhibition of lipoxgenase, alpha-amylase and alpha-glucosidase. Overall, the present study concludes that the H. indicus may be a suitable repellant and fumigant agent against different pests of stored products and a possible antioxidant, anti-inflammatory, and anti-diabetic agent.  相似文献   

14.
八种菊科中草药抗霉菌及饲料霉变的研究   总被引:6,自引:0,他引:6  
从我国南方霉变的粮食和饲料中分离得到黄曲霉、黑曲霉等10种霉菌并作为供试菌;采用抑菌圈及二倍稀释法研究了野菊花、艾叶等8种菊科中草药的提取物拮抗此10种供试霉菌的活性.结果表明,蒲公英、虾须草等6种中草药及8种中草药的等比混合品抗霉菌活性最强,对各种供试菌的MIC值均不超过12.5g/L,其中中草药混合品和蒲公英显示了MIC的最小值0.391g/L.对此8种中草药提取物及其混合品抗饲料霉变及黄曲霉毒素的产生做了进一步研究,发现中草药混合品的拮抗霉菌生长及黄曲霉毒素产生的效力很强,对黄曲霉毒素的抑制率可超过95%,显示了广阔的应用前景.  相似文献   

15.
A new series of 1,4-dihydropyridine derivatives (2a–h, 3a–e, and 4a–e) were systematically designed and synthesized via ultrasound irradiation methods with easy work-up and good yields. Compounds structures were confirmed by IR, 1H NMR, 13C NMR, and mass spectra. The synthesized compounds were screened for both antimicrobial and anticoagulant activities. Compound 2e (MIC: 0.25?μg/mL) was highly active against Escherichia coli and compound 2c (MIC: 0.5?μg/mL) was also highly active against Pseudomonas aeruginosa compared with ciprofloxacin. (MIC: 1?μg/mL) The antifungal activity of 2c (MIC: 0.5?μg/mL) against Candida albicans was high relative to that of clotrimazole (MIC: 1?μg/mL). Anticoagulant activity was determined by activated partial thromboplastin time (APTT) and prothrombin time (PT) coagulation assays. Compound 4-(4-hydroxyphenyl)-2,6-dimethyl-N3,N5-bis(5-phenyl-1,3,4-thiadiazol-2-yl)-1,4-dihydropyridine-3,5-dicarboxamide 3d (>1000?s in APTT assays) was highly active in anticoagulant screening compared with the reference of heparin.Cytotoxicity was evaluated using HepG2 (liver), HeLa (cervical), and MCF-7 (breast) cancer cell lines, with high toxicities observed for 2c (GI50?=?0.02?μm) against HeLa cell line and 2e (GI50?=?0.03?μm) equipotant against MCF-7 cell line. Therefore, the compounds 2e, 2c and 3d can serve as lead molecules for the development of new classes of antimicrobial and anticoagulant agent.  相似文献   

16.
The essential oil of Artemisia judaica L., grown on Sinai Peninsula of Egypt, was extracted via hydrodistillation. Chromatographic separation on repeated silica gel columns led to isolate two compounds namely piperitone and trans-ethyl cinnamate. Insecticidal, antifeedant and antifungal properties of the isolated compounds were examined. Both compounds showed pronounced insecticidal and antifeedant activity against the third instar larvae of Spodoptera littoralis (Boisd). trans-Ethyl cinnamate (LD50 = 0.37 μg/larva) was more toxic than piperitone (LD50 = 0.68 μg/larva). The two isolated compounds revealed antifeedant activity in a concentration dependent manner, with complete feeding inhibition at a concentration of 1000 μg/ml. When tested for antifungal activity against four plant pathogenic fungi, the isolated compounds exhibited a moderate to high activity.  相似文献   

17.
Extracts of cultures grown in liquid or on solid rice media of the fungal endophyte Ampelomyces sp. isolated from the medicinal plant Urospermum picroides exhibited considerable cytotoxic activity when tested in vitro against L5178Y cells. Chromatographic separation yielded 14 natural products that were unequivocally identified based on their 1H and 13C NMR as well as mass spectra and comparison with previously published data. Six compounds (2, 4, 5, 7, 9 and 11) were natural products. Both fungal extracts differed considerably in their secondary metabolites. The extract obtained from liquid cultures afforded a pyrone (2) and sulfated anthraquinones (7 and 9) along with the known compounds 1, 3, 6 and 8. When grown on solid rice medium the fungus yielded three compounds 4, 5 and 11 in addition to several known metabolites including 6, 8, 10, 12, 13 and 14. Compounds 4, 8 and 10 showed the strongest cytotoxic activity against L5178Y cells with EC50 values ranging from 0.2–7.3 μg/ml. Furthermore, 8 and 10 displayed antimicrobial activity against the Gram-positive pathogens, Staphylococcus aureus, S. epidermidis and Enterococcus faecalis at minimal inhibitory concentrations (MIC) of 12.5 μg/ml and 12.5–25 μg/ml, respectively. Interestingly, 6 and 8 were also identified as constituents of an extract derived from a healthy plant sample of the host plant U. picroides thereby indicating that the production of bioactive natural products by the endophyte proceeds also under in situ conditions within the host plant.  相似文献   

18.
Zinc and its derivatives requirement increased to enhance human immunity against the different pandemics, including covid-19. Green synthesis is an emerging field of research. Zinc oxide (ZnO) nanoparticles have been prepared from Anoectochilus elatus and characterized using absorption, vibrational and electron microscope analysis. They were carried for antibacterial, inflammatory control tendency, and potential antioxidant activities. The brine shrimp lethal assay tested the biologically derived nanomaterial toxicity and the lethal concentration (LC50) is 599.79 µg/ml. The inhibition against the important disease-causing pathogens was measured against four-gram negative, gram-positive bacteria and two fungus pathogens. The nanomaterial exposed inhibition zone for gram-positive bacteria between 17 mm and 25 mm. The inhibition zone against gram-negative bacteria exists between 19 mm and 24 mm. The anti-inflammatory activity was assessed by inhibition of protein denaturation and protease inhibitory activity using nanomaterial. The antioxidant activity was examined using four assays for the therapeutic activities. The average size range of 60–80 nm nanoparticles has prepared and exposed the good biological activity between 50 µg/ml and 100 µg/ml. The comparative results of anti-inflammatory and antioxidant assay results with standards such as Aspirin and vitamin C exposed that two to three times higher concentrations are required for the fifty percent of inhibitions. The prepared low-cost nanoparticle has exhibited excellent biological activity without any side effects and may enhance immunity.  相似文献   

19.
Primaquine homodimers, e.g. symmetric PQ-diamides of dicarboxylic acids containing 4 to 8 carbon atoms, were evaluated against Plasmodium berghei hepatic stages and P. falciparum blood stages, as well as against three cancer cell lines. Novel PQ-homodimers exerted much higher activity against hepatic stages, but less pronounced activity against blood stages in comparison to the parent drug. The submicromolar activity of succinic, fumaric and maleic derivatives against P. berghei was determined (IC50 values: 726.2, 198.1 and 358.4 nM, respectively). Our results indicated that the length and type of spacer between two PQ moieties highly modified the antiproliferative activities of PQ-homodimers. The general antiproliferative activity of the adipic and mesaconic derivatives against three cancer cell lines (MCF-7, HCT116, H 460) was observed (GI50 = 1.78–13.7 and 2.36–4.31 µM, respectively), but adipic derivative was less toxic to human embryonic kidney cells (HEK 293). High selectivity of fumaric and suberic derivatives against breast adenocarcinoma cell line MCF-7 was detected. These two compounds have shown no antiproliferative activity against other tumor cells and HEK 293.  相似文献   

20.
It is of interest to analyze the antioxidant, antimicrobial and cytotoxicity activity of n-hexane extract of Cayratia trifolia L. (C. trifolia). The antimicrobial activity of n-hexane extract of C. trifolia was determined using disc diffusion method against six selected pathogenic microorganisms. The cytotoxicity potential of n-hexane plant extract was also studied against A2780 cell lines by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Results, n-hexane extract of C. trifolia possess significant antioxidant activity with significant IC50 values in radical scavenging assays. In antimicrobial studies, the maximum zone of inhibition was found in the range of 19.0 ± 0.1 to 22.0 ± 0.1 mm. In MTT assay, inhibition of cell growth with minimal IC50 values of 46.25±0.42μg/mL against A2780 cell lines was observed. Thus, n-hexane extract of C. trifolia is a possible antioxidant, antimicrobial and cytotoxicity agent.  相似文献   

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