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91.
《亚太热带病杂志(英文版)》2014,4(5):378-383
ObjectiveTo determine the total phenolics and flavonoids and to evaluate antioxidant and antimicrobial activities of different extracts from fruits of Datura metel (D. metel).MethodsDifferent crude extracts from the fruits of D. metel were subjected to determination of total phenolics, flavonoids, antioxidant and antimicrobial activities by established methods.ResutlsThe total phenolics results showed that ethyl acetate extract was the most efficient (60.26%) compared to hexane, chloroform, butanol and methanol extracts which had phenolic contents of 50.08, 35.50, 52.54 and 26.49%, respectively. Almost similar results were obtained from the fruits crude extracts for total flavonoids and results found that methanol crude extract was the highest (1.71%) compared to other crude extracts. The antioxidant activity results showed that methanol extract acted the highest activity compared to other extracts and in the order of methanol>ethyl acetate>hexane>chloroform>butanol extract. All extracts were displayed moderate antibacterial potential against the tested bacteria such as Staphylococcus aureus, Escherichia coli and Pseudomonus aeruginosa in the range of 0%–10%.ConclusionsThe results of this present study clearly showed that the crude extracts of D. metel demenstrated antimicrobial and antioxidant activities and it may act as potential antioxidant sources for human biological system. 相似文献
92.
《Journal of Pharmaceutical Analysis》2020,10(4):334-345
Tetrahydrocurcumin (THC) is one of the major metabolites of curcumin (CUR), an ancient bioactive natural polyphenolic compound. This research article describes both the solid and liquid state characterization of THC using advanced spectroscopic and thermo-analytical techniques. Anti-inflammatory, anti-oxidant, and neuroprotective activities of THC were investigated using in vitro cell lines. Liquid chromatography-mass spectrometry analysis revealed that our sample comprised 95.15% THC, 0.51% tetrahydrodemethoxycurcumin (THDC), 3.40% hexahydrocurcumin, and 0.94% octahydrocurcumin. Gas chromatography-mass spectrometry analysis indicated the presence of 96.68% THC and 3.32% THDC. THC in solution existed as keto-enol tautomers in three different forms at different retention time, but the enol form was found to be dominant, which was also supported by nuclear magnetic resonance analysis. THC was thermally stable up to 335.55 °C. THC exhibited more suppression of cytokines (TNF-α, IL-1β, and MIP-1α) than CUR in a concentration-dependent manner in mouse splenocytes, while NK-cell and phagocytosis activity was increased in macrophages. THC showed a significant reduction of free radicals (LPO) along with improved antioxidant enzymes (SOD and catalase) and increased free radical scavenging activity against ABTS+ radicals in HepG2 cells. THC displayed higher protection capability than CUR from oxidative stress and neuronal damage by improving cell viability against H2O2 induced HepG2 cells and MPP+ induced SH-SY5Y cells, respectively, in a concentration-dependent manner. Thus, a variation of the biological activities of THC might rely on its keto-enol form and the presence of other THC analogs as impurities. The present study could be advantageous for further research on THC for better understanding its physicochemical properties and biological variation. 相似文献
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94.
PURPOSE
The aim of the present study was to assess the effect of ascorbic acid, ethanol and acetone on microtensile bond strength between fiber posts pre-treated with hydrogen peroxide and composite resin cores.MATERIALS AND METHODS
Twenty four fiber posts were pre-treated with 24% hydrogen peroxide and divided into 4 groups as follows: G1: no treatment, as control group; G2: treatment with 10% ascorbic acid solution for 5 minutes; G3: treatment with 70% ethanol solution for 5 minutes; and G4: treatment with 70% acetone solution for 5 minutes. Each fiber post was surrounded by a cylinder-shaped polyglass matrix which was subsequently filled with composite resin. Two sections from each sample were selected for microtensile test at a crosshead with speed of 0.5 mm/min. Statistical analyses were performed using one-way ANOVA and a post hoc Tukey HSD test. Fractured surfaces were observed under a stereomicroscope at ×20 magnification. The fractured surfaces of the specimens were observed and evaluated under a SEM.RESULTS
Means of microtensile bond strength values (MPa) and standard deviations in the groups were as follows: G1: 9.70±0.81; G2: 12.62±1.80; G3: 16.60±1.93; and G4: 21.24±1.95. G4 and G1 had the highest and the lowest bond strength values, respectively. A greater bond strength value was seen in G3 compared to G2. There were significant differences between all the groups (P<.001). All the failures were of the adhesive mode.CONCLUSION
Application of antioxidant agents may increase microtensile bond strength between fiber posts treated with hydrogen peroxide and composite cores. Acetone increased bond strength more than ascorbic acid and ethanol. 相似文献95.
Oxidative stress is an important factor for aging. The antioxidative enzymes glutathione peroxidase (GPx), glutathione reductase (GRd) and superoxide dismutase (SOD) play a crucial role protecting the organism against the age-dependent oxidative stress. Glutathione (GSH) is present in nearly all living cells. GSH is one of the main antioxidants in the cell and it serves several physiological functions. Our purpose was to evaluate the age-related changes in mitochondrial GPx, GRd and SOD activities, and mitochondrial GSH pool in the brains of young (3months) and aged rats (24months). We also investigated whether melatonin administration influences these brain mitochondrial enzyme activities and GSH levels in young and aged rats. The results showed that GPx activity increased with age, whereas melatonin treatment decreased GPx activity in the aged rats at levels similar to those in young and young+melatonin groups. The activities of GRd and SOD, however, did not change with age. But, melatonin treatment increased SOD activity in the aged rats. GSH levels, which also increased with age, were not modified by melatonin treatment. The reduction in the SOD/GPx and GR/GPx ratios with age was prevented by melatonin administration. Together, our results suggest that the age-related oxidative stress in rat brain mitochondria is more apparent when the antioxidant enzyme ratios are analyzed instead of their absolute values. The antioxidative effects of melatonin were also supported by the recovery of the enzyme ratios during aging. 相似文献
96.
目的检测感染隐孢子虫奶牛血液免疫和抗氧化体系指标。方法对安徽省某奶牛场325头奶牛粪样采用饱和蔗糖溶液漂浮法检测隐孢子虫感染情况。选择隐孢子虫感染强阳性的7头奶牛作为感染组,同时取7头隐孢子虫粪检阴性奶牛作为对照组,早晨饲喂前从奶牛颈静脉采血,分别测定总蛋白(TP)、白蛋白(ALB)、免疫球蛋白(IgG、IgM和IgA)、中性粒细胞吞噬率、T淋巴细胞转化率、白细胞介素-2(IL-2)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、丙二醛(MDA)、一氧化氮(NO)、丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、碱性磷酸酶(ALP)、血糖(GLU)、甘油三脂(TG)、Cl-和Ca2+等19项指标。结果 325头奶牛隐孢子虫感染率为31.7%(103/325),根据卵囊的形态和大小,初步鉴定为安氏隐孢子虫(Cryptosporidium andersoni)。与对照组相比,感染组奶牛血清中TP、ALB、IgM、IgA、GSH-Px、ALT、AST、ALP和Cl-含量无显著变化(P>0.05);血清中MDA和NO含量分别升高59.9%和28.1%(P<0.05或0.01);而血清中IgG、SOD、GLU、TG、Ca2+和IL-2含量,以及T淋巴细胞转化率和中性粒细胞吞噬率分别降低了32.9%、11.1%、18.6%、78.9%、14.5%、7.0%、22.0%和20.2%(均P<0.05)。结论感染隐孢子虫奶牛部分免疫指标下降,抗氧化酶活性降低,清除体内自由基的能力减弱。 相似文献
97.
98.
《Renal failure》2013,35(5):479-486
Free oxygen radicals and nitric oxide (NO) play a crucial role in the pathogenesis of myoglobinuric acute renal failure (ARF). In this study, we aimed to investigate the effect of melatonin, a potent free radical scavenger, on the myoglobinuric ARF formed by injecting hypertonic glycerol intramuscularly (im). The rats were randomly divided into 4 Groups. Rats in Group 1 were given saline and those in Groups 2, 3, and 4 were injected with glycerol (10 mL/kg) im. Concomitant and 24 hours after glycerol injection Group 3 (5 mg/kg) and Group 4 (10 mg/kg) were administrated melatonin intraperitoneally. Forty‐eight hours after the glycerol injection, the blood and kidneys of the rats were taken under anesthesia. Kidney morphology and the levels of urea, creatinine and nitric oxide metabolites (NOx) in the plasma and the enzyme activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) and the level of malondialdehyde (MDA) in the kidney were determined. In both groups of melatonin administration, there was no protective effect of melatonin. Moreover, melatonin significantly decreased the level of NO. As a result, we suggest that the decreasing effect of melatonin on NO, which is a strong vasodilatator, may further increase the renal ischemia in this model. Thus, melatonin may have worsening rather than beneficial effects on myoglobinuric ARF. 相似文献
99.
A. E. Moubasher A. M. E. El Din M. E. Ali W. T. El‐sherif H. D. Gaber 《Andrologia》2013,45(2):135-139
Cryopreservation of human spermatozoa offers a pre‐therapeutic possibility of preserving progenity in patients with testicular tumours. We aimed to investigate effects of cryopreservation and addition of catalase on sperm motility, vitality and DNA integrity in fresh and swim‐up spermatozoa. Semen samples were collected from 50 fertile men. Each sample was divided into two parts. First part was subdivided into two equal aliquots: both cryopreserved with and without catalase. The second part was subdivided into two equal aliquots: both processed by swim up and then cryopreserved with or without catalase. Semen analyses, sperm vitality and sperm DNA integrity were performed. Sperm concentration showed significant decrease while percentage of progressive motility, sperm vitality and % of DNA damage showed significant increase in processed and cryopreserved processed samples when compared with fresh and cryopreserved fresh samples. There was no significant difference in sperm concentration while there was significant increase in % of progressive motility and sperm vitality and % of DNA damage showed significant decrease in samples with catalase when compared with samples without catalase (either fresh or processed). Catalase supplementation (fresh and processed) during cryopreservation results in better post‐thawing percentage of progressive motility and percentage of sperm vitality and improved DNA integrity. 相似文献
100.