scholarly journals The synthesis and versatile reducing power of low-valent uranium complexes

2020 ◽  
Vol 49 (43) ◽  
pp. 15124-15138
Author(s):  
Michael A. Boreen ◽  
John Arnold
Keyword(s):  
Reducing Power ◽  
Uranium Complexes ◽  
Low Valent

This synthesis and diverse reactivity of uranium(iii) and uranium(ii) complexes is discussed.

COMPARISON OF VARIOUS METHODS FOR THE CHEMICAL ASSAY OF CORTICOIDS IN URINE

1955 ◽  
Vol 18 (4) ◽  
pp. 374-378
Author(s):  
Mogens Sprechler
Keyword(s):  
Calibration Curve ◽  
Periodic Acid ◽  
Reducing Power ◽  
Standard Technique ◽  
Phosphomolybdic Acid ◽  
Florisil Column ◽  
Chemical Assay ◽  
Chromatographic Procedure ◽  
Acid Reagent

SUMMARY Since 1949 about 10,000 urinary corticoid analyses have been performed routinely in our laboratory. The method used for this purpose was described in 1950 (Sprechler). We determine the corticoids which can be extracted from the urine with chloroform immediately after acidification to pH 1. The extract is washed with sodium hydroxide and water, a Girard separation is performed, and finally the reducing power of the ketonic fraction is measured by means of the phosphomolybdic acid reagent reaction. During the last few years two other chemical reactions have been used for comparison: The formaldehyde and the Porter-Silber method. After a thorough examination of the above methods a standard technique was followed. In the formaldehyde method a microdiffusion in a Conway unit was used instead of distillation of the formaldehyde following the oxidation with periodic acid. The calibration curve was corrected for loss of material by taking the standard doses of DOC through all the procedures of the method. A micromodification of the Porter-Silber method was chosen. Furthermore attempts were made to determine how specific the chromatographic procedure is in the determination of steroids in urinary extracts. For this purpose the Florisil column was used, and the technique described by Nelson & Samuels was followed. Finally we have investigated the glucuronide-bound corticoids in urine in a smaller series of objects.

Characterization of non polar-polar solvent extracts from some tea plantation shade tree leaves with special reference to antioxidant and antibacterial activities

2020 ◽  
pp. 15-21
Author(s):  
Arindam Ghosh ◽  
Soumya Majumder ◽  
Sumedha Saha ◽  
Malay Bhattacharya
Keyword(s):  
Cardiac Glycosides ◽  
Polar Solvent ◽  
Reducing Power ◽  
Scavenging Activity ◽  
Shade Trees ◽  
Crude Fibre ◽  
Shade Tree ◽  
Dpph Scavenging Activity ◽  
Dpph Scavenging

Beneficial properties of shade trees of tea plantations other than their medicinal properties have been extensively studied. This research was initiated to explore the properties of some shade trees with special emphasis on their antioxidant and antibacterial properties. Leaves from shade tree like Dalbergia sissoo (DS), Cassia siamea (CS), Derris robusta (DR), Leucaena leucocephala (LL), Acacia lenticularis (AL) and Melia azedarach (MA) were used for the study. Characterization of shade tree leaves by determination of moisture, crude fibre and ash content and tests of non polar – polar solvent extracts for steroid, tannins, cardiac glycosides and coumarin, free radical scavenging, ferric reducing power, NO scavenging activities, quantification of Flavonoids and antibacterial activity were conducted. The average moisture, crude fibre and ash percentage of shade tree plants were found to be 62.95, 11.28 and 1.86 respectively. Methanol, ethanol, acetone and ethyl acetate respectively proved to be the most potent solvent for various phytochemical extractions as it gave positive results for tests like tannin, steroid, cardiac glycosides and coumarin. AL (91.46%), DR (92.69%), LL (94.32%) and MA (93.34%) leaf extracts showed a high level of DPPH scavenging activity in their water extracts. In DS (88.11%) and CS (83.23%) maximum DPPH scavenging activity was observed in Diethyl ether and Methanol extracts respectively.  Acetone extracts were more active than the water extracts in exhibiting ferric reducing power and NO scavenging activity. Summation of the quantity revealed that DS showed maximum presence of flavonoids and acetone as most potential for isolation of flavonoids. The decreasing order of summative antibacterial activity was recorded in DS, followed by CS, DR, AL, MA and LL. Chloroform showed the highest summative inhibition zone followed by ethanol, ethyl acetate, diethyl ether, acetone, water,  hexane, benzene and methanol. The antioxidant and antibacterial potential of shade trees were established.

Turmeric and cinnamon dominate in antioxidant potential among four major spices

2017 ◽  
Vol 26 (1) ◽  
pp. 27 ◽  
Author(s):  
B Saranya ◽  
T Sulfikarali ◽  
S Chindhu ◽  
A M Muneeb ◽  
N K Leela ◽  
...  
Keyword(s):  
Methanol Extract ◽  
Reducing Power ◽  
Black Pepper ◽  
Chloroform Extract ◽  
Antioxidant Potential ◽  
Total Phenol Content ◽  
Power Method ◽  
Phenol Content ◽  
Dpph Assay ◽  
Synthetic Antioxidant

Antioxidant activity of sequential extracts of black pepper, ginger, turmeric and cinnamon was determined by DPPH assay, phosphomolybdate method and ferric reducing power method and compared with that of the synthetic antioxidant BHA. The results revealed that methanol extract of cinnamon has highest antioxidant potential followed by chloroform extract of turmeric. The antioxidant potential was also correlated with total phenol content.  

Physiochemical properties and antioxidant potential of Persea Americana seed oil

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Seed Oil ◽  
Antioxidant Activities ◽  
Radical Scavenging ◽  
Reducing Power ◽  
Acid Value ◽  
Persea Americana ◽  
Antioxidant Potential ◽  
Physiochemical Properties ◽  
Physiochemical Parameters ◽  
Ic50 Value

Oil extracted from Persea Americana seed was assayed for its physiochemical properties and antioxidant potential using various standard methods. The oil content of the seed was found to be < 10%. Brownish-red color oil was liquid at room temperature, with specific gravity of 0.91±0.02 g/mL. Other physiochemical parameters determined were; acid value (4.51±0.08 mgKOH/g), %FFA (2.26±0.08), peroxide value (2.40±0.57 mgO2/Kg), ester value (31.26±0.03 mgKOH/g), saponification value (35.76±0.07 mgKOH/g) and iodine value (23.5±0.07). The results of the antioxidant activities of the seed oil showed that the flavonoid content (80.00±1.41 mgQE/g) was ~10 folds higher than the phenolic content (8.27±0.06 mgGAE/g). The DPPH radical scavenging value was found to be 51.54±0.25% with an IC50 value of 4.68±0.02 mg/mL and reducing power with an average absorbance of 0.85±0.01 and an IC50 value of 0.001±0.02 mg/mL. Gallic acid showed better antioxidant activities than the oil studied. The results obtained in this study showed that Persea Americana seed oil has nutritional, industrial as well as medicinal potentials.

Antioxidant Activity, Phenolic Content and Hematoprotective Effects of Cleome arabica Polyphenolic Leaf Extract

2019 ◽  
Author(s):  
C. Tigrine ◽  
A. Kameli
Keyword(s):  
Antioxidant Activity ◽  
Biological Effects ◽  
Reducing Power ◽  
Hematological Toxicity ◽  
Protective Effects ◽  
Ferrous Ions ◽  
Polyphenolic Extract ◽  
Cleome Arabica

In this study a polyphenolic extract from Cleome arabica leaves (CALE) was investigated for its antioxidant activity in vitro using DPPH•, metal chelating and reducing power methods and for its protective effects against AraC-induced hematological toxicity in vivo using Balb C mice. Results indicated that CALE exhibited a strong and dose-dependent scavenging activity against the DPPH• free radical (IC50 = 4.88 μg/ml) and a high reducing power activity (EC50 = 4.85 μg/ml). Furthermore, it showed a good chelating effects against ferrous ions (IC50 = 377.75 μg/ml). The analysis of blood showed that subcutaneous injection of AraC (50 mg/kg) to mice during three consecutive days caused a significant myelosupression (P < 0.05). The combination of CALE and AraC protected blood cells from a veritable toxicity. Where, the number of the red cells, the amount of hemoglobin and the percentage of the hematocrite were significantly high. On the other hand, AraC cause an elevation of body temperature (39 °C) in mice. However, the temperature of the group treated with CALE and AraC remained normal and did not exceed 37.5 °C. The observed biological effects of CALE, in vitro as well as in vivo, could be due to the high polyphenol and flavonoid contents. In addition, the antioxidant activity of CALE suggested to be responsible for its hematoprotective effect.

Comparison Among Five Eucalyptus Species Based on Their Leaf Contents of Some Primary and Secondary Metabolites

2019 ◽  
Vol 20 (7) ◽  
pp. 573-587
Author(s):  
Alyaa Nasr ◽  
Tehmina Saleem Khan ◽  
Shi-Ping Huang ◽  
Bin Wen ◽  
Jian-Wen Shao ◽  
...  
Keyword(s):  
Secondary Metabolites ◽  
Protocatechuic Acid ◽  
Antioxidant Activities ◽  
Reducing Power ◽  
Renewable Resource ◽  
Total Phenolic ◽  
Eucalyptus Species ◽  
Primary And Secondary Metabolites ◽  
Acetone Water ◽  
Phenolic Constituents

Background: Eucalyptus belongs to the Myrtaceae family. It is the most planted hardwood forest crop worldwide, representing a global renewable resource of fiber, pharmaceuticals and energy. Objective: To compare the five species, E. maidenii, E. robusta, E. citriodora, E. tereticornis and E. camaldulensis, seeking for the richest source of nutrients and pharmaceuticals. Methodology: Eucalyptus samples were subjected to some chemical determinations for both primary and secondary metabolites to verify their nutritional and pharmaceutical importance related to different extracts. GC-MS analysis was applied to detect the presence of some individual phenolic constituents in their leaves. Results: E. robusta recorded the maximum contents of carbohydrates (40.07%) and protein (31.91%). While E. camaldulensis contained the highest contents of total phenolic compounds (46.56 mg/g), tannins (40.01 mg/g) and antioxidant activities assayed by the phosphomolybednum method (57.60 mg/g), followed by E. citridora. However, E. tereticornis exhibited the highest reducing power ability (151.23 mg/g). The GC-MS highlighted 20 phenolic constituents and antioxidants which varied in their abundance in Eucalyptus leaves, 8 individual phenolics (hydroquinone, hesperitin, pyrogallol, resorcinol, protocatechuic acid, naringenin, chlorogenic acid and catechin) were maximally recorded with E. camaldulensis and secondly, with E. citridora in case of at least 5 components. Nevertheless, gallic and quinic acids were more abundant in the leaves of E. tereticornis, which may explain its high corresponding reducing powers. Conclusion: Acetone-water combination has enhanced phenolics extraction from Eucalyptus tissues. This is the first report aiming to compare between the aforementioned Eucalyptus species highlighting either their nutritional or medicinal importance.

Dipeptidyl Peptidase IV Inhibitors for Nonalcoholic Fatty Liver Disease – Systematic Review and Metanalysis

2020 ◽  
Vol 16 ◽  
Author(s):  
Lucas Ribeiro dos Santos ◽  
Marcio Luis Duarte ◽  
Maria Stella Peccin ◽  
Antônio Ricardo de Toledo Gagliardi ◽  
Tamara Melnik
Keyword(s):  
Hepatic Steatosis ◽  
Grey Literature ◽  
Specific Treatment ◽  
Reducing Power ◽  
Dipeptidyl Peptidase ◽  
Dipeptidyl Peptidase Iv ◽  
Cochrane Library ◽  
Vast Number ◽  
Dpp Iv ◽  
Dipeptidyl Peptidase Iv Inhibitors

Introduction:: Hepatic steatosis is a frequent condition, that afflicts, especially, obese and insulin resistant patients; diagnosis is made, usually, through imaging tests. Despite the high prevalence and risk of complications, there is no specific treatment approved, though a vast number of medications have been tested. Objective:: To determine the efficacy of dipeptidyl peptidase IV inhibitors (i DPP-IV) in the treatment of NAFLD. Methods:: We searched the electronic databases of the Cochrane Library, MEDLINE, EMBASE and LILACS, as well as reference lists of the included studies and grey literature; 9 studies were selected for inclusion. Results:: 7 studies were used for metanalysis, for 3 outcomes. i DPP-IV showed an ALT-reducing power of MD -10.83 [95% CI 35.23 to 13.57] at 3 months and MD -9.27 [95% CI 10.92 to -7.62] at 6 months of intervention, as well as reduction of hepatic steatosis via MRI of SMD 0.10 [95% CI 0.31 to 0.50]; the overall incidence of adverse events was very low. The studies were considered of low and very low quality by the GRADE evaluation. Conclusion:: Because of the poor overall quality of the studies and heterogeneity of the population analyzed, i DPP-IV did not show efficacy on inflammatory markers or fibrosis in patients with NAFLD.

Investigation of Oral Subacute Toxicity and In-Vitro Antioxidant Activity of Standardized Methanolic Extract of Quercus serrata Leaves

2020 ◽  
Vol 16 ◽  
Author(s):  
Maibam Beebina Chanu ◽  
Biseshwori Thongam ◽  
Khumukcham Nongalleima ◽  
Hans Raj Bhat ◽  
Surajit Kumar Ghosh ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Antioxidant Activity ◽  
Biochemical Parameters ◽  
Methanolic Extract ◽  
Reducing Power ◽  
Quercus Serrata ◽  
Control Group ◽  
Blood Cell Count ◽  
Toxicological Profile

Background: Quercus serrata Murray leaves have been used traditionally in the treatment of diabetes, dysmenorrhoea, inflammation and urinary tract infection. So, far no study had been reported on the toxicological profile and antioxidant properties of the plant. Objective: The present study was aimed to investigate the in-vivo toxicological profile and in-vitro antioxidant activities of the methanolic extract of standardized Quercus serrata leaves. Methods: Per-oral sub-acute toxicity study was performed in rats using three dose levels (200, 400 and 800 mg/kg b.w.) of the extract for 28-days. Control group received gum acacia suspended in water. Bodyweight was measured weekly. Biochemical parameters were analysed using the serum, the blood-cell count was done using whole blood. Pathological changes were also checked in highly perfused tissues. Further, in-vitro reducing power assay, nitric oxide scavenging assay, DPPH free-radical scavenging assay were performed to check the antioxidant activity of the extract. Results: There were no significant alterations in the blood-cell count and biochemical parameters analysed in the treatment group when compared with the normal control. Histopathology study of liver, kidney, pancreas, heart and brain revealed normal cellular architecture in the treatment groups alike the control group animals. Quercus serrata also showed a significant reduction of DPPH with IC50 4.48±0.254 µg/mL, in-vitro reducing power activity with IC50121.65±0.320 µg/mL and nitric oxide scavenging activity IC50 106.43±0.338 µg/mL. Conclusion: The above study showed that standardized methanolic extract of Quercus serrata leaves was safe after subacute oral administration in rats and has good antioxidant potential.

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