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1.
Our purpose was to determine the effects of six cigarette toxicants (pyridine, nicotine, 2-ethylpyridine, 3-ethylpyridine, p-cresol, and pyrazine) on three types of cultured mammalian cells (human umbilical vein endothelial cells [HUVECs], human microvascular endothelial cells [HMVECs], and NIH 3T3 cells) using a cell proliferation/survival assay. Synchronized cells were cultured in proliferation or survival medium containing various doses (10(-18)M-10(-2)M) of the tested chemicals. After 48 h, cells were counted using a hemacytometer. The no observable adverse effect level (NOAEL), lowest observable adverse effect level (LOAEL), and the efficacy were determined for each compound in the cell proliferation and survival assays. Pyridine and p-cresol did not show significant effects with any cell types, except at high doses. Derivitization of the pyridine ring altered its potency, especially when an ethyl group or nitrogen was added. In survival medium, nicotine stimulated proliferation of all three cell types at doses found in smoker's serum (10(-8)M-10(-7)M). For HUVEC and HMVEC, 2-ethylpyridine, 3-ethylpyridine, and pyrazine inhibited proliferation in proliferation medium and induced cell death in survival medium at attomolar and femtomolar doses. All chemicals, except pyridine and pyrazine, stimulated NIH 3T3 cell proliferation at low doses and induced cell death at high doses. LOAELs and efficacies revealed that endothelial cells from a developing organ (umbilical cord) were more sensitive to these chemicals than endothelial cells from an adult organ (lung). 3-Ethylpyridine and pyrazine, which induced cell death at low doses, are added to consumer products and should be subjected to further toxicological testing. 相似文献
2.
目的 通过超声辅助大孔树脂对荆芥穗Schizonepetae Spica水提物中总黄酮和总酚类化合物进行富集并对比处理前后化合物含量及活性变化。方法 从7种不同类型树脂中筛选超声辅助最佳树脂型号,在吸附动力学和吸附热力学研究下,对超声温度、功率、上样质量浓度及解吸溶剂百分比等影响因素进行工艺优化。测定了优化处理前后各成分含量及活性变化。结果 动力学和热力学的研究表明,荆芥穗总黄酮适用于Langmuir模型,且吸附过程为自发吸热熵增,总酚则为自发放热熵减并适用于Freundlich模型,据此不同的吸附机制优化了2类成分同时富集的最佳工艺,在超声辅助AB-8大孔树脂,温度25 ℃、时间2.5 h,功率150 W,上样质量浓度0.1 g/mL,70%乙醇解吸附的过程下,荆芥穗水提物中总黄酮和总酚类化合物含量增加2~3倍,其单体成分的含量及抗氧化和神经氨酸酶抑制活性均显著增加。结论 超声辅助大孔树脂技术为荆芥穗总黄酮和总酚类成分的有效可行富集技术。 相似文献
3.
干姜超临界CO2提取物质量控制的研究 总被引:3,自引:0,他引:3
目的:建立干姜超临界CO2提取物的有效部位质量控制的方法。方法∶采用薄层色谱法,以石油醚(60~90℃)醋酸乙酯冰醋酸(8∶3∶0.2)为展开剂,5%香草醛硫酸溶液为显色剂,对本品进行鉴别;并采用紫外双波长分光光度法和高效液相色谱法对本品进行总酚及有效成分6姜酚的含量测定。结果∶总酚在9.668~38.67μg·mL-1呈良好线性关系(r=0.9999),平均回收率为97.7%,RSD1.96%;6姜酚在0.20~2.00μg呈良好线性关系(r=0.9999),平均回收率为97.9%,RSD0.33%。结论∶方法准确,灵敏、专属性强,可作为该原料的全面质量控制标准。 相似文献
4.
Vladimir Plyuta Julia Zaitseva Elena Lobakova Natalia Zagoskina Alexander Kuznetsov Inessa Khmel 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2013,121(11):1073-1081
In the natural environment, bacteria predominantly exist in matrix‐enclosed multicellular communities associated with various surfaces, referred to as biofilms. Bacteria in biofilms are extremely resistant to antibacterial agents thus causing serious problems for antimicrobial therapy. In this study, we showed that different plant phenolic compounds, at concentrations that did not or weakly suppressed bacterial growth, increased the capacity of Pseudomonas aeruginosa PAO1 to form biofilms. Biofilm formation of P. aeruginosa PAO1 was enhanced 3‐ to 7‐fold under the action of vanillin and epicatechin, and 2‐ to 2.5‐fold in the presence of 4‐hydroxybenzoic, gallic, cinnamic, sinapic, ferulic, and chlorogenic acids. At higher concentrations, these compounds displayed an inhibiting effect. Similar experiments carried out for comparison with Agrobacterium tumefaciens C58 showed the same pattern. Vanillin, 4‐hydroxybenzoic, and gallic acids at concentrations within the range of 40 to 400 μg/mL increased the production of N–3‐oxo‐dodecanoyl‐homoserine lactone in P. aeruginosa PAO1 which suggests a possible relationship between stimulation of biofilm formation and Las Quorum Sensing system of this bacterium. Using biosensors to detect N‐acyl‐homoserine lactones (AHL), we demonstrated that the plant phenolics studied did not mimic AHLs. 相似文献
5.
《International journal of food sciences and nutrition》2013,64(3):239-249
The stem, leaf, and root of Tinospora cordifolia (willd.) have been highly exploited for medicinal preparations; however, the nutritional and nutraceutical potential of its attractive red berries (fruits) have not so far been studied. Pigments, berberine (107.0 mg/100 g) and lycopene (50.8 mg/100 g), were identified in the deseeded fruit. Total phenol content in the fruit was 3.2 mg gallic acid equivalent/g. The IC50 of DPPH√ (82, and 468 ppm) and OH√ (100, and 1,000 ppm) scavenging activity, and the EC50 of reducing power (2,616, and 1,472 ppm) of hexane and methanol extracts, respectively, were observed. Oxygen radical absorbance capacities of the fruit extracts (150 and 300 ppm) were 1,107 and 2,614 μM trolox equivalent/g, respectively. Nutrient composition including carbohydrate (18.4%), proteins (1.5%), lipids (6%) of which ~62% was unsaturated fatty acids, vitamins like ascorbic acid (0.24 μg), niacin (0.7 mg), and tocopherols (2.4 mg) in 100 g fruits were determined. Potassium content was 1.2 g/100 g dry tissue of berries. These findings show that components of T. cordifolia fruit could be bioactive and used in food, pharmaceutical, and cosmetics. 相似文献
6.
7.
Cauliflower (Brassica oleraceae L. var. Botrytis) is a good source of bioactive compounds, such as glucosinolates, phenolic compounds and vitamins. In this study, the effects of some processes (i.e. boiling, steaming) on the sinigrin bioaccessibility as a major glucosinolate found in cruciferous vegetables after in vitro digestion, also in vitro antimutagenic activities, total phenols and total antioxidant capacities of cauliflower were determined. The sinigrin content was reduced by approximately 9.6% and 29.1% in steamed and boiled cauliflower (p > 0.05), respectively. After in vitro simulated digestion, sinigrin content was decreased by 26.4% in raw samples, increased by 29.5% and 114.7% in steamed and boiled samples, respectively. In all samples, mutagenic effect to Salmonella typhimurium TA 100 was not seen. When samples were steamed, phenol content was increased by 14.83%. After boiling total phenol content of cauliflower was decreased by 1.8%. Total antioxidant capacities (TAC) measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3 ethylbenzothiazoline-6-sulfonic acid) (ABTS) methods were increased by 47% and 39%, respectively (p < 0.05) in steamed samples and decreased by 8% and 7% with boiling, respectively (p > 0.05). TAC in raw sample of cauliflower, which was investigated in phosphomolybdenum assays, was determined as 18.7 mg ascorbic acid equivalents (AAE)/100 g. In all cases, the highest antioxidant activity was determined in the steamed samples, while the lowest antioxidant activity was in boiled samples. 相似文献
8.
目的建立基于药物体系的肉桂特征图谱质量表征关联分析方法,全面评价肉桂饮片质量。方法采用HPLC-PDA法建立肉桂饮片特征图谱,筛选7个特征峰并通过相对保留时间表征其质的关联性;同时测定6个主要有效指标性成分(原儿茶酸、表儿茶素、香豆素、肉桂醇、肉桂酸、肉桂醛)的含量并表征主要酚类成分和主要苯丙素类成分的含量,通过关联度等概念表征其量的关联性。结果以批号13为基准,基于质的表征模式及关联分析,肉桂饮片特征图谱中筛选的7个特征峰中有酚类成分2个、苯丙素类成分5个,15批肉桂饮片色谱图中均含有此7个特征峰。基于量的表征模式及关联分析,批号14有效指标性成分总体含量高于基准批号13,批号4、6、8、10含量与基准批号13关联性较高,综合评价得出批号14、13、4、6、8、10优良度居前。结论在定性的基础上进行定量表征,可全面评价肉桂饮片质量优次,为肉桂饮片资源筛选、药物原料质量控制及应用提供依据,同时为中药质量评价提供新的方法。 相似文献
9.
目的 采用超高效液相色谱-四级杆-飞行时间质谱(UPLC-Q-TOF-MS)技术对中药复方渴络欣胶囊中的化学成分进行研究。方法 采用ACQUITY UPLC HSS T3 C18色谱柱(100 mm×2.1 mm,1.8 μm),以甲醇-0.1%甲酸水溶液为流动相梯度洗脱,体积流量为0.3 mL/min;采用ESI源在正、负离子模式下分别采集数据。根据化合物精确相对分子质量及二级碎片离子信息,结合参考文献数据,鉴定渴络欣胶囊的主要化学成分。结果 从渴络欣胶囊中分离和鉴定出54个化学成分,包括蒽醌类化合物10个、黄酮类化合物10个、萜类化合物7个、酚类化合物16个等。结论 首次采用UPLC-Q-TOF/MS联用技术研究渴络欣胶囊中化学成分,进一步明确了其物质基础。 相似文献
10.