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Comprehensive scientific data provide evidence that isolated phytochemicals or whole plant foods may beneficially modify carcinogenesis. The aim of this study was to evaluate the oncostatic activities of Rhus coriaria L. (sumac) using animal models (rat and mouse), and cell lines of breast carcinoma. R. coriaria (as a powder) was administered through the diet at two concentrations (low dose: 0.1% (w/w) and high dose: 1 % (w/w)) for the duration of the experiment in a syngeneic 4T1 mouse and chemically-induced rat mammary carcinoma models. After autopsy, histopathological and molecular analyses of tumor samples in rodents were performed. Moreover, in vitro analyses using MCF-7 and MDA-MB-231 cells were conducted. The dominant metabolites present in tested R. coriaria methanolic extract were glycosides of gallic acid (possible gallotannins). In the mouse model, R. coriaria at a higher dose (1%) significantly decreased tumor volume by 27% when compared to controls. In addition, treated tumors showed significant dose-dependent decrease in mitotic activity index by 36.5% and 51% in comparison with the control group. In the chemoprevention study using rats, R. coriaria at a higher dose significantly reduced the tumor incidence by 20% and in lower dose non-significantly reduced tumor frequency by 29% when compared to controls. Evaluations of the mechanism of oncostatic action using valid clinical markers demonstrated several positive alterations in rat tumor cells after the treatment with R. coriaria. In this regard, histopathological analysis of treated tumor specimens showed robust dose-dependent decrease in the ratio of high-/low-grade carcinomas by 66% and 73% compared to controls. In treated rat carcinomas, we found significant caspase-3, Bax, and Bax/Bcl-2 expression increases; on the other side, a significant down-regulation of Bcl-2, Ki67, CD24, ALDH1, and EpCam expressions and MDA levels. When compared to control specimens, evaluation of epigenetic alterations in rat tumor cells in vivo showed significant dose-dependent decrease in lysine methylation status of H3K4m3 and H3K9m3 and dose-dependent increase in lysine acetylation in H4K16ac levels (H4K20m3 was not changed) in treated groups. However, only in lower dose of sumac were significant decreases in the expression of oncogenic miR210 and increase of tumor-suppressive miR145 (miR21, miR22, and miR155 were not changed) observed. Finally, only in lower sumac dose, significant decreases in methylation status of three out of five gene promoters–ATM, PTEN, and TIMP3 (PITX2 and RASSF1 promoters were not changed). In vitro evaluations using methanolic extract of R. coriaria showed significant anticancer efficacy in MCF-7 and MDA-MB-231 cells (using Resazurin, cell cycle, annexin V/PI, caspase-3/7, Bcl-2, PARP, and mitochondrial membrane potential analyses). In conclusion, sumac demonstrated significant oncostatic activities in rodent models of breast carcinoma that were validated by mechanistic studies in vivo and in vitro.  相似文献   
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马尾松化学热磨机械浆酶法改性研究   总被引:1,自引:0,他引:1  
利用漆树漆酶/介体体系对马尾松化学热磨机械浆进行生物酶处理及后续H2O2漂白,探索漆酶生物改性最佳工艺条件。结果表明,在漆酶用量为2.0 U/g,2,2’-连氮-二(3-乙基噻唑-6-磺酸)(ABTS)用量0.5%,酶处理温度50℃,酶处理时间60 min时,与对照浆相比,纸浆白度可提高3.0%ISO,抗张指数、撕裂指数分别提高22.5%、7.9%。纤维长度、粗度分析及扫描电镜谱图显示,漆酶处理只发生在纤维表面,有利于表面木素的降解溶出,从而提高了纸浆的白度和可漂性。  相似文献   
4.
火炬树果穗红色素的提取及稳定性的研究   总被引:7,自引:1,他引:7  
研究了从火炬树果穗中提取红色素的方法,并对其进行精制。对色素的基本性质进行了初探。实验表明该色素耐热、耐光等较好,是一种值得开发的色素。  相似文献   
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The purpose of this study was to determine the reducing power, metal chelating, and radical scavenging capabilities of water and ethanol extracts of sumac (Rhus coriaria L.), comparatively. The water and ethanol extracts of sumac were evaluated for their radical scavenging activities by means of the DPPH and DMPD assays. Water extract of sumac (R. coriaria L.) scavenged radicals effectively with EC50 values of 36.4 ??g/ml for DPPH free radical and 44.7 ??g/ml for DMPD cation radical. Similarly, the total reducing power of water extract was found higher than ethanol extract in both potassium ferricyanide reduction (FRAP) and cupric ions reduction capacity methods (CUPRAC). 2,2′-Bipyridine was used to determine the metal chelating activity and the result of water extract was found higher than ethanol extract. Total phenolic and total flavonoid contents of both extracts were studied as well. The values of water extract were found to be higher than that of ethanol extract. The present study found that water extracts of sumac (R. coriaria L.) have effective antioxidant and radical scavenging activities as compared to ethanol extracts.  相似文献   
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漆树资源在我国有着悠久的栽培和利用历史,形成了中华民族特有的生漆文明。漆树具有高等植物的生态功能,并向人类提供大量的生物质材料。生漆作为漆树的次生代谢产物,伴随人类走过7000多年的历程,成为世界文明史、科学技术史、工艺美术史上的一朵奇葩。随着人类技术进步、经济发展、文化创造以及物质化应用需求的增长,漆树资源的开发向多元化、深层次推进,从文化到人类经济社会,从髹漆艺术品到生物基材料产品,从医药保健品到精细化学品,从石油化工领域到军工产品等等,应用领域不断拓展,桼彩光辉。  相似文献   
7.
火炬树树叶清除自由基作用的研究   总被引:6,自引:0,他引:6  
孟洁  胡博路  张建生 《食品科学》2002,23(8):258-260
分别用DPPH法、TBA法和化学发光法测定了火炬树树叶提取物对自由基的清除作用。结果表明:火炬树树叶各提取物对DPPH自由基均有清除作用,其中以乙酸乙酯提取物的清除能力最强;各提取物对亚油酸脂质过氧化体系亦有良好的抑制作用,乙酸乙酯提取物的抑制作用强于水提取物。火炬树树叶水提物对碱性连苯三酚体系产生的超氧阴离子自由基(O2•)也有较强的清除作用。  相似文献   
8.
Sumac, Rhus coriaria L., is a Mediterranean plant showing several useful properties, such as antioxidant and neuroprotective effects. Currently, there is no evidence about its possible neuroprotective action in Parkinson’s disease (PD). We hypothesized that sumac could modulate mitochondrial functionality in fibroblasts of familial early-onset PD patients showing PARK2 mutations. Sumac extract volatile profile, polyphenolic content and antioxidant activity have been previously characterized. We evaluated ROS and ATP levels on sumac-treated patients’ and healthy control fibroblasts. In PD fibroblasts, all treatments were effective in reducing H2O2 levels, while patients’ ATP content was modulated differently, probably due to the varying mutations in the PARK2 gene found in individual patients which are also involved in different mitochondrial phenotypes. We also investigated the effect of sumac extract on THP-1-differentiated macrophages, which show different embryogenic origin with respect to fibroblasts. In THP-1 macrophages, sumac treatment determined a reduction in H2O2 levels and an increase in the mitochondrial ATP content in M1, assuming that sumac could polarize the M1 to M2 phenotype, as demonstrated with other food-derived compounds rich in polyphenols. In conclusion, Rhus coriaria L. extracts could represent a potential nutraceutical approach to PD.  相似文献   
9.
采用紫外分光光度法测定五种不同产地五倍子中单宁含量,单宁酸的平均回收率为97.67%,RSD为2.0%(n=9),单宁酸含量在62.26%~67.87%不等,结果表明不同产地五倍子中单宁酸含量差别较大。  相似文献   
10.
彭涛  林鹿  雷晓春  劳宗广 《中华纸业》2007,28(11):27-30
利用日本漆树漆酶与介体ABTS构成的体系(LMS)对马尾松化学热磨机械浆(CTMP)进行生物处理及后续H2O2漂白,分析了酶用量、介体用量、pH值、酶处理温度和酶处理时间对纸浆白度和强度性能的影响,探索LMS生物改性的最佳工艺条件。并利用傅里叶变换红外光谱技术分析用LMS处理前后的纸浆,结果表明,经LMS处理,纸浆中的发色基团减少,并伴随着木素的降解溶出,从而提高了纸浆的白度和可漂性。  相似文献   
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