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71.
In this study the effects of propionate, L-valine, L-isoleucine, and DL-methionine on the metabolism of D-3-hydroxybutyrate (D-3-HB) were investigated in the isolated perfused non-working rat heart.Propionate inhibited the utilization (the total removal of D-3-HB by the heart) but stimulated the oxidation of D-3-HB. The degree of D-3-HB inhibition was dependent on the concentrations of propionate and D-3-HB. Furthermore, increasing the concentration of DL-hydroxybutyrate (DL-3-HB) to 16 or 30 mM abolished the inhibitory effect of propionate (4 mM). Whereas increasing the perfusion pressure from 40ndash;80 mmHg stimulated the utilization and the oxidation of D-3-HB; propionate (4 mM) severely inhibited the utilization of D-3-HB at 40 and 80 mmHg, when DL-3-HB was 5 mM. On the other hand insulin (2 mU .ml-1) stimulated the utilization and the oxidation of D-3-HB at perfusion pressure of 40 mmHg, but showed no effect at 80 mmHg. Insulin was unable to overcome the inhibitory effect of propionate. Propionate improved the oxidation but inhibited the utilization of D-3-HB, while L-valine and L-isoleucine showed no effects on the utilization and the oxidation of D-3-HB. DL-methionine inc d the utilization of D-3-HB by 14% without noticeable effects on the oxidation of D-3-HB. None of these anaplerotic substrates were suitable to ameliorate the utilization of D-3-HB.  相似文献   
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Lavandula genus is an important member of Labiatae (Lamiaceae) family. People use commonly Lavandula stoechas as a medicinal plant for various diseases around the world and also in Turkey. The aim of this study was to investigate cytotoxic and genotoxic effects of aqueous extracts (40, 80 and 120 g/L) from L. stoechas flowers on Allium cepa root tip meristem cells. For this purpose, A. cepa onion bulbs were treated with the above-mentioned L. stoechas flower extracts for 72 h. Spring water (pH 7.3) was used as a control. The result of this study sowed that aqueous extracts reduced mitotic index, but induced chromosome aberrations and mitotic aberrations in comparison with control, significantly (p < 0.05). Aqueous extracts induced breaks, stickiness, pole deviations and micronuclei. Furthermore, these effects were related to extract concentrations. These results showed that L. stoechas aqueous extracts have cytotoxic and genotoxic effects.  相似文献   
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目的:从肉苁蓉中提取并测定总黄酮含量,选择最佳提取工艺条件。方法:以芦丁为对照品,用分光光度法在最大吸收波长510nm对其含量进行测定。结果:测得样品中总黄酮含量C=9.33%,最佳提取工艺:乙醇浓度为70%、料液比1:40、回流时间2h、回流温度70℃。结论:选用芦丁为对照品应用于紫外分光光度法测定肉苁蓉总黄酮含量准确度较高,方法简单,是切实可行含量测定方法。  相似文献   
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BackgroundBlack pericarp rice has recently become popular among rice consumers for its diverse health benefits specially anti-cancer effect. Cyanidin-3-Glucosides (C3G), an prominant bioactive component of anthocyanins which is abundantly present in black pericarp rice.ObjectivesWe investigated, how effectively it can be used to fortify Cyanidin-3-Glucosides (C3G) content in red and white pericarp polished rice or rice based bakery products for more nutritional value.MethodIn the present study, we have characterized several black pericarp rice cultivars along with some red pericarp and white pericarp rice cultivars by physicochemical including mineral profiling, and quantified the C3G by UFLC and LCMS.ResultsC3G content was significantly reduced from raw rice to cooked rice condition. All the black pericarp rice cultivars synthesized C3G, while this content was not detected in red and white pericarp rice cultivars. However, when 25% of black pericarp rice were mixed with 75% red or white pericarp polished rice, C3G content was significantly retained in cooked rice conditions. Formulation of rice-based bakery food product using black pericarp rice powder was also remarkably retained the C3G content as compared to that of cooking. Black rice is harder in texture, difficult to digest and needs higher energy for cooking. Therefore, we tried to circumvent these challenges by fortifying 25% of black pericarp rice with white or red pericarp rice.ConclusionFortification of C3G enriched black rice (25%) with red or white pericarp rice (75%) might bring a better nutritional quality in both cooking and baking condition. This may lead a way to the effective management of the non-communicable disease such as cancer for common rice consuming population.  相似文献   
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Prucalopride (PCD), is a modern medication approved by the United States in 2018 to alleviate constipation caused by motility issues. PCD demonstrates a strong affinity and selectivity toward the 5-HT4 receptor. The study here introduces a feasible, direct, non-extractive, and affordable pathway for PCD analytical tracking. The fluorimetric study is based on the on–off effect on the emission amplitude of fluorone-based dye (pyrosin B). In a one-pot experiment, the complex between PCD and pyrosin B is formed instantly in an acidic medium. Correlation between decreased pyrosin B emission and PCD concentrations provides a linear calibration plot from 50 to 900 ng/mL. PCD–dye complex system affecting variables were meticulously tuned. The values of the estimated limit of quantitation and limit of detection for the current methodology were 47.5 and 15.7 ng/mL, respectively. Conformity of the strategy validity was achieved by a comprehensive study of the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use criteria. The method was convincingly applied for PCD assay in tablets and content uniformity investigation. Furthermore, PCD tracking in the spiked biological fluid was applied. Finally, the method uses distilled water as dispersing medium which rise accommodation with the green chemistry principle.  相似文献   
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The medicinal plant, Nothapodytes foetida contains a number of important alkaloids like camptothecin (an anticancer drug molecule) but its concentration is less to meet the existing demand of this important molecule, so in an effort for accessible availability of camptothecin. An endophyte (designated ZP5SE) was isolated from the seed of Nothapodytes foetida and was examined as potential source of anticancer drug lead compound i.e. camptothecin, when grown in Sabouraud liquid culture media under shake flask conditions. The presence of anticancer compound (camptothecin) in this fungus was confirmed by chromatographic and spectroscopic methods in comparison with authentic camptothecin. Isolated endophyte (Neurospora crassa) producing camptothecin may become an easily accessible source for the production of precursor anticancer drug molecule in future at large scale.  相似文献   
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