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31.
One strain-many compounds (OSMAC) manipulation of the sponge-derived fungus Pestalotiopsis heterocornis XWS03F09 resulted in the production of new secondary metabolites. The chemical study of the fermentation, cultivated on 3% artificial sea salt in the rice media, led to the isolation of twelve compounds, including eight new polyketide derivatives, heterocornols Q–X (1–8), one new ceramide (9), and three known analogues (10–12). The structures and absolute configurations of the new compounds were elucidated by spectroscopic data and calculated ECD analysis. Heterocornols Q (1) and R (2) are novel 6/5/7/5 tetracyclic polyketide derivatives featuring dihydroisobenzofuran and benzo-fused dioxabicyclo [4.2.1] nonane system, which might be derived from the acetyl-CoA by epoxidation, polyene cyclization, and rearrangement to form the core skeleton. Compound 12 showed moderate or weak antimicrobial activities against with MIC values ranging from 25 to 100 μg/mL. Heterocornols T and X (7 and 8) could inhibit the production of LPS-induced NO significantly, comparable to dexamethasone. Further Western blotting analysis showed 7 and 8 markedly suppressed the iNOS protein expression in LPS-induced RAW 264.7 cells in a dose-dependent manner. The result showed that 7 and 8 might serve as potential leads for development of anti-inflammatory activity.  相似文献   
32.
2014年世界卫生组织首份全球抗菌素耐药报告显示全世界面临严重的公共卫生威胁,2021年农业农村部制定了《全国兽用抗菌药使用减量化行动方案》(2021-2025),从国家层面实施综合治理策略和措施,鼓励替代抗菌药物的研制和创新。大黄素甲醚、大黄酸作为植物蒽醌类有效成分,具有抗微生物、抗炎、抗氧化、神经保护等药理作用,但对其抗菌、抗病毒、抗炎症相关的作用机制和产业化工艺缺少详细报道。本文对国内外已经发表的专利文献、期刊文献进行综述,总结其抗菌、抗病毒、抗炎作用机制及其生产工艺,以期为进一步开发利用提供科学支撑。  相似文献   
33.
Three new 9,11-secosterols, pinnisterols A–C (1–3), were isolated from a gorgonian coral Pinnigorgia sp., collected off the waters of Taiwan. The structures of these compounds were elucidated on the basis of spectroscopic methods. The new sterols 1 and 3 displayed significant inhibitory effects on the generation of superoxide anions and the release of elastase by human neutrophils, and sterol 1 was found to show moderate cytotoxicity in hepatic stellate cells (HSCs).  相似文献   
34.
目的 探讨白子菜提取物对急性痛风性关节炎大鼠模型抗炎作用。方法 将72只Wistar大鼠随机分为9组(每组8只):空白组、模型组、秋水仙碱组、白子菜水提取物低、中、高剂量组、白子菜醇提取物低、中、高剂量组。造模5 h后开始连续灌药,7 d后取材,观察各组大鼠关节炎症情况,关节组织单位面积内炎症细胞计数及检测血清白介素-1β(interleukin-1 β,IL-1β)、肿瘤坏死因子-α(tumour necrosis factor-α,TNF-α)浓度。结果 中、高剂量白子菜提取物组与秋水仙碱组在足趾炎症情况显著低于模型组(P<0.05)。在淋巴细胞、中性粒细胞计数方面各药物组显著低于模型组(P<0.05),各药物组间无明显差异(P>0.05)。秋水仙碱组TNF-α表达水平显著低于模型组(P<0.05)。秋水仙碱组及白子菜醇提取物中剂量组IL-1β表达水平显著低于模型组(P<0.05)。结论 秋水仙碱及中剂量白子菜醇提物对急性痛风性关节大鼠模型具有抗炎免疫作用。  相似文献   
35.
[目的]研究白头翁、黄连、大青叶等复方药效学作用.[方法]白头翁复方口服液体外大肠杆菌抑菌杀菌试验、大鼠足跖肿胀法抗炎试验、小鼠番泻叶法止泻试验和小鼠冰醋酸法镇痛试验.[结果]白头翁复方口服液最小抑菌浓度(minimum inhibitory concentration,MIC)1×2-3,生药含量为125 mg/mL;最小杀菌浓度(minimum bactericidal concentration,MBC)1×2-2,生药含量为250 mg/mL;对二甲苯刺激导致的大鼠炎性反应有抗炎作用,剂量为1.5 g/kg·bw;连续饲喂小鼠3d,剂量为0.75、1.5 g/kg· bw时对番泻叶造成的小鼠腹泻有治疗作用;剂量为0.75、1.5、3.0 g/kg· bw,对冰醋酸造成的小鼠腹痛有止痛效果.[结论]白头翁复方口服液具有明显的抗菌、抗炎、止泻与镇痛作用.  相似文献   
36.
丹翘灌注液抗炎镇痛作用的研究   总被引:1,自引:0,他引:1  
研究丹翘灌注液的抗炎镇痛作用。采用二甲苯致小鼠耳廓肿胀、棉球致小鼠肉芽肿、小鼠醋酸扭体反应、小鼠福尔马林致痛模型观察丹翘灌注液的抗炎和镇痛作用。40、20、10 g/kg的丹翘灌注液能不同程度的抑制二甲苯引起的小鼠耳廓肿胀、棉球引起的肉芽肿增生;不同程度的减少醋酸引起的小鼠扭体次数和福尔马林引起的舔足时间。结果表明,丹翘灌注液具有抗炎、镇痛的作用。  相似文献   
37.
Two new briarane-type diterpenoids, briarenolides K (1) and L (2), were isolated from an octocoral identified as Briareum sp. The structures of new briaranes 1 and 2 were elucidated by spectroscopic methods. In the in vitro anti-inflammatory effects test, briaranes 1 and 2 were found to significantly inhibit the accumulation of the pro-inflammatory iNOS protein of the lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells.  相似文献   
38.
β-Agonists have been shown to display anti-inflammatory properties in several experimental models. The aim of this study was to investigate the anti-inflammatory properties of clenbuterol (CB), administered either intravenously or by aerosol, in comparison with fluticasone propionate (FP) in recurrent airway obstruction (RAO)-susceptible horses. Eight horses, of which five were known to be susceptible to RAO, underwent an inhalation challenge with Aspergillus fumigatus (AF) antigen and were treated with CB intravenously, CB by aerosol, or FP by aerosol. Twenty-four hours after the challenge, bronchoalveolar lavage was performed, the total and differential cell counts were assessed, and cytokines were measured in isolated alveolar macrophages. After challenge with AF, RAO-susceptible horses showed an increase in total cell count, based on an increase in macrophages and lymphocytes, which was inhibited by treatment with intravenous CB, aerosolized CB and aerosolized FP. Neutrophil ratios were decreased when treated with aerosolized CB and FP. Expression of interleukin (IL)-1β and IL −8 was significantly increased after AF challenge .Interleukin −1β was significantly decreased following treatment with intravenous CB, aerosolized CB and aerosolized FP, whereas only FP decreased the expression of IL-8. These data suggest that the anti-inflammatory property of CB provide new opportunities in the therapeutic intervention of early inflammation in RAO.  相似文献   
39.
YH Chen  J Kuo  JH Su  TL Hwang  YH Chen  CH Lee  CF Weng  PJ Sung 《Marine drugs》2012,10(7):1566-1571
A novel 15C compound, pseudoalteromone B (1), possessing a novel carbon skeleton, was obtained from a marine bacterium Pseudoalteromonas sp. CGH2XX. This bacterium was originally isolated from a cultured-type octocoral Lobophytum crassum, that was growing in cultivating tanks equipped with a flow-through sea water system. The structure of 1 was established by spectroscopic methods. Pseudoalteromone B (1) displayed a modestly inhibitory effect on the release of elastase by human neutrophils.  相似文献   
40.
目的 研究复方白头翁散的抗炎作用.方法 采用小鼠耳廓肿胀法、皮内染料渗出法、棉球肉芽肿胀法及大鼠足跖肿胀法观察复方白头翁散对急慢性炎症的作用.结果 小鼠耳壳二甲苯致肿实验结果 显示,与阴性对照组相比,低剂量组差异不显著,中剂量组差异显著P<0.05,高剂量组差异极显著P<0.01;与阳性对照组相比,低剂量组差异极显著P...  相似文献   
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