SOME FACTORS AFFECTING THE DETERMINATION OF HOT-WATER-SOLUBLE BORON FROM PODZOL SOILS USING AZOMETHINE-H

1979 ◽  
Vol 59 (3) ◽  
pp. 241-247 ◽  
Author(s):  
UMESH C. GUPTA
Keyword(s):  
Prince Edward Island ◽  
Sandy Loam ◽  
Water Soluble ◽  
Hot Water ◽  
Colorimetric Determination ◽  
Factors Affecting ◽  
Water Extracts ◽  
Percent Recovery

A study was conducted on some factors affecting the colorimetric determination of B using the azomethine-H reagent on soils from Prince Edward Island. Two fine sandy loam soils (A and B) were used for the main study and additional soil samples varying in organic matter (OM) were used to assess the role of OM. Soils containing less than 3.0% OM and 3.1–4.1% OM required 0.4 g and 0.8 g charcoal per 25 g soil, respectively, to produce clear hot-water extracts. Quantities of greater than 0.8 g charcoal were necessary to produce clear extracts from soils containing more than 4.1% OM. Colored hot-water extracts of soil resulted in higher absorbance than those hot-water extracts treated with charcoal as measured at 430 mμ. Additions of 0.8 and 1.6 g charcoal or greater to the soils (A and B) resulted in considerably lower recoveries of B as noted by comparing the absorbance obtained using 0.4 and 0.8 g, respectively. Storage of azomethine-H up to 7 days did not affect the absorbance of the B-azomethine-H complex. One hour after the addition of azomethine-H, a maximum absorbance was found which persisted for up to 4 h. The percent recovery of B added to the two soils was about 10–12% less using azomethine-H as compared to those obtained using the carmine method. However, the mean hot-water-soluble B contents of 10 soils as measured using the carmine and azomethine-H reagents were 0.70 and 0.66 ppm. Pure B solutions when boiled with charcoal resulted in losses of B added. Such losses of B increased with increasing rates of charcoal.

Factors affecting in vitro and in vivo antioxidant effects. Experimental conditions and nature of oxidants determine antioxidant efficacy

2021 ◽  
pp. 1-9
Author(s):  
Etsuo Niki
Keyword(s):  
Biological Molecules ◽  
Experimental Conditions ◽  
Factors Affecting ◽  
Beneficial Effects ◽  
Multiple Oxidants ◽  
Antioxidant Effects

Reactive oxygen and nitrogen species have been implicated in the onset and progression of various diseases and the role of antioxidants in the maintenance of health and prevention of diseases has received much attention. The action and effect of antioxidants have been studied extensively under different reaction conditions in multiple media. The antioxidant effects are determined by many factors. This review aims to discuss several important issues that should be considered for determination of experimental conditions and interpretation of experimental results in order to understand the beneficial effects and limit of antioxidants against detrimental oxidation of biological molecules. Emphasis was laid on cell culture experiments and effects of diversity of multiple oxidants on antioxidant efficacy.

Nitrogen enrichment of animal bone-derived biochars as an agricultural NP-fertilizer 

2021 ◽  
Author(s):  
Gerhard Soja ◽  
Dominik Tauber ◽  
Jan Höllrigl ◽  
Andrea Mayer ◽  
Christoph Pfeifer
Keyword(s):  
Phosphorus Content ◽  
Water Soluble ◽  
Meat Production ◽  
Colorimetric Determination ◽  
Animal Bone ◽  
Soluble Phosphorus ◽  
Sorption Potential ◽  
P Supply ◽  
Np Fertilizer

<p>Food processing creates many by-products, and not all of them are used efficiently. Especially animal-based side products are frequently considered as waste with costly disposal requirements. For recycling of the nutrients contained in these residues, also under consideration of the hygienic specifications, pyrolysis can be used to create animal bone-based biochars. A lab-scale pyrolysis reactor (Pyreka 3.0) was used to produce biochars from different bone fractions of cattle and pigs after these bones had originated as waste from abbatoir operations. This study had the objective to investigate the potential of the bone chars to serve as a phosphorus (P) supply for agricultural purposes and to study the ammonium sorption potential of these chars.</p><p>The total phosphorus content of bones reached up to 140 mg/g. The water-soluble phosphorus content was in the range of 0.16 – 0.93 mg/g, an increase in pyrolysis temperature from 350 °C to 500 °C or 650 °C increased the water-soluble content by 13.3 or 12.2 % respectively. The citric acid soluble phosphorus content was between 1.75 – 2.19 mg/g. After pyrolysis temperatures of 350 °C, slightly more phosphorus dissolved in the coal products than at 500 °C (+2.7 %) and at 650 °C (+5.5 %).</p><p>The ammonium sorption capacity of biochars produced by varying pyrolytic processes was investigated by a series of sorption experiments. The removal of ammonium by the biochars from an aqueous ammonium solution was measured by using colorimetric determination of the ammonium content. The maximum ammonium sorption results were achieved by biochars produced from bovine heads and feet respectively at a temperature of 900°C and activated with H<sub>2</sub>O.</p><p>When exposed to a solution containing 50 mg/L of ammonium, these biochars adsorbed 1.23 and 1.14 mg ammonium/g biochar, respectively. The possibility to enrich abattoir waste biochars, which are depleted in nitrogen because of the pyrolysis process, with ammonium gained from a nitrogen-enriched biogas slurry produced from animal residues of the meat production process was tested using a substitute slurry made with ammonium sulfate. The highest absorbance rate using the substitute slurry containing 10 g/L ammonium was achieved by biochar made from bovine heads and resulted in 43.1 mg ammonium/g biochar.</p><p>This study shows that bone-based biochars enriched with nitrogen from e.g. biogas digestates have significant potential as an NP-fertilizer that supports the strategies of circular economy.</p>

scholarly journals Skin Electrical Resistance Measurement of Oxygen-Containing Terpenes as Penetration Enhancers: Role of Stratum Corneum Lipids

Molecules ◽  
2019 ◽  
Vol 24 (3) ◽  
pp. 523 ◽  
Author(s):  
Xue-min Zhu ◽  
Yu Li ◽  
Fei Xu ◽  
Wei Gu ◽  
Guo-jun Yan ◽  
...  
Keyword(s):  
Stratum Corneum ◽  
Electrical Resistance ◽  
Attenuated Total Reflection ◽  
Penetration Enhancers ◽  
Rapid Screening ◽  
Factors Affecting ◽  
Skin Cell ◽  
First Time

The measurement of skin electrical resistance (SER) has drawn a great deal of attention for the rapid screening of transdermal penetration enhancers (PEs). However, the mechanisms underlying the SER measurement are still unclear. This study was to investigate the effects and mechanisms of seven oxygen-containing terpenes on the SER kinetics. Stratum corneum (SC) lipids were proved to play a key role in SER measurement. Then, the factors affecting the SER measurement were optimized. By the determination of SER kinetics, cyclic terpenes (1,8-cineole, terpinen-4-ol, menthol and α-terpineol) were demonstrated to possess higher enhancement ratio (ER) values compared with linear terpenes (linalool, geraniol and citral). For the first time, the linear correlation was found between ER of terpenes and the interaction energy of terpene–ceramide complexes revealed by molecular simulation. The attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) analysis revealed that the effect of cyclic terpenes on SC lipid arrangement was obviously stronger than that of linear terpenes. In addition, by evaluating HaCaT skin cell viability, little difference was found between the toxicities of cyclic and linear terpenes. In conclusion, measurement of SER could be a feasible approach for the efficient evaluation of the PEs that mainly act on SC lipids.

Contributions to the Analysis of Rubber. I. Determination of the Water-Soluble Components of Rubber

1937 ◽  
Vol 10 (3) ◽  
pp. 574-583
Author(s):  
P. Dekker
Keyword(s):  
Acetic Acid ◽  
Acid Reflux ◽  
Water Soluble ◽  
Hot Water ◽  
Water Bath ◽  
Vulcanized Rubber ◽  
Magnesium Compounds ◽  
Calcium Compounds ◽  
Soluble Components

Abstract 1. It is shown that the methods which are ordinarily used for determining water-soluble substances in raw rubber give low results, and are quite useless for vulcanized rubber. 2. New analytical procedures are developed for determining the water-soluble substances in raw rubber and in vulcanized rubber. These procedures are carried out in the following manner. (a) Raw Rubber.—Heat 2 grams of rubber in 80 cc. of xylene and 5 cc. of acetic acid on a water bath until the rubber is completely dissolved, add 5 cc. of acetic acid and 10 cc. of water, heat for 3–4 hours on the water bath with frequent agitation, transfer to a distilling flask (rinsing the first flask with 50 cc. of hot water), distill the xylene with steam, filter the residual solution, evaporate the filtrate on a water bath; and dry at 100° C. (b) Vulcanized Rubber and Rubber Mixtures.—First extract the sample with acetone, heat 2 grams of the acetone-extracted sample with 80 cc. of xylene on a water bath, add 5 cc. of acetic acid, reflux the mixture on an oil bath, after complete dissolution add 5 cc. of acetic acid and 10 cc. of water, heat the solution for 2 hours on an oil bath at 110–120° C., distill the xylene, as in the determination with raw rubber, filter the residue, evaporate the filtrate to dryness, take up the residue in 50 cc. of water, pass a current of hydrogen sulfide through the solution for 10 minutes to precipitate zinc as sulfide, filter, evaporate the filtrate, and dry the residue at 100° C. 3. In the presence of calcium compounds, magnesium compounds, glue and textiles, the method gives false results. Modifications of the method are therefore recommended, whereby these substances are eliminated.

EFFECTS OF APPLIED AND RESIDUAL BORON ON THE NUTRITION OF CABBAGE AND FIELD BEANS

1984 ◽  
Vol 64 (4) ◽  
pp. 571-576 ◽  
Author(s):  
UMESH C. GUPTA ◽  
J. A. CUTCLIFFE
Keyword(s):  
Prince Edward Island ◽  
Field Experiments ◽  
Leaf Tissue ◽  
Water Soluble ◽  
Hot Water ◽  
Boron Toxicity ◽  
First Year ◽  
Application Rates ◽  
Seed Yields ◽  
Field Beans

Field experiments were conducted at four locations in Prince Edward Island to determine the effect of applied B on leaf tissue B and yields of beans (Phaseolus vulgaris L.) and cabbage (Brassica oleracea var. capitata L.) in the year of application of B and again the following year. Application rates of 8.8 kg B∙ha−1 reduced bean seed yields at all locations and the 4.4-kg B∙ha−1 rate reduced yields at two locations in the first year. Leaf tissue B levels > 109 μg∙g−1 are clearly toxic for beans and seriously reduced bean yields. Furthermore, the yield and visual symptom data strongly suggest that tissue B levels even as low as 60 μg∙g−1 are toxic for this crop. No significant reductions in bean yields were noted in the second year crop, even at the 8.8 kg B∙ha−1 rate. Rates of up to 8.8 kg B∙ha−1 did not cause any reduction in cabbage yield even during the year of application. Leaf tissue B concentrations as high as 71–132 μg∙g−1 were not related to any B toxicity in cabbge. Added B did not increase yield of either beans or cabbage. Even though leaf tissue B levels as low as 16 μg∙g−1 in cabbage and 26 μg∙g−1 in beans occurred, no B deficiency was found. After the first and second years of beans the hot-water-soluble B in the soil ranged from 1.4 to 1.9 and from 0.8 to 1.2 μg∙g−1, respectively, where B had been applied at 8.8 kg∙ha−1. Key words: Cabbage, beans, boron toxicity, tissue boron, yields

Validated Spectrophotometric and RP-HPLC–DAD Methods for the Determination of Ursodeoxycholic Acid Based on Derivatization with 2-Nitrophenylhydrazine

2017 ◽  
Vol 100 (3) ◽  
pp. 677-685
Author(s):  
Dina S El-Kafrawy ◽  
Tarek S Belal ◽  
Mohamed S Mahrous ◽  
Magdi M Abdel-Khalek ◽  
Amira H Abo-Gharam
Keyword(s):  
Ursodeoxycholic Acid ◽  
Internal Standard ◽  
Acid Hydrazide ◽  
Acid Group ◽  
Reversed Phase ◽  
Water Soluble ◽  
Precolumn Derivatization ◽  
Colorimetric Determination ◽  
Pharmaceutical Dosage Forms

Abstract This work describes the development, validation, and application of two simple, accurate, and reliable methods for the determination of ursodeoxycholic acid (UDCA) in bulk powder and in pharmaceutical dosage forms. The carboxylic acid group in UDCA was exploited for the development of these novel methods. Method 1 is the colorimetric determination of the drug based on its reaction with 2-nitrophenylhydrazine hydrochloride in the presence of a water-soluble carbodiimide coupler [1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride] and pyridine to produce an acid hydrazide derivative, which ionizes to yield an intense violet color with maximum absorption at 553 nm. Method 2 uses reversed-phase HPLC with diode-array detection for the determination of UDCA after precolumn derivatization using the same reaction mentioned above. The acid hydrazide reaction product was separated using a Pinnacle DB C8 column (4.6 × 150 mm, 5 μm particle size) and a mobile phase consisting of 0.01 M acetate buffer (pH 3)–methanol–acetonitrile (30 + 30 + 40, v/v/v) isocratically pumped at a flow rate of 1 mL/min. Ibuprofen was used as the internal standard (IS). The peaks of the reaction product and IS were monitored at 400 nm. Different experimental parameters for both methods were carefully optimized. Analytical performance of the developed methods were statistically validated for linearity,range, precision, accuracy, specificity, robustness, LOD, and LOQ. Calibration curves showed good linear relationships for concentration ranges 32–192 and 60–600 μg/mL for methods 1 and 2, respectively. The proposed methods were successfully applied for the assay of UDCA in bulk form, capsules, and oral suspension with good accuracy and precision. Assay results were statistically compared with a reference pharmacopeial HPLC method, and no significant differences were observed between proposed and reference methods.

A simple colorimetric determination of the free amino groups in water soluble chitin derivatives using genipin

2010 ◽  
Vol 19 (3) ◽  
pp. 683-689 ◽  
Author(s):  
Luz M. Ramos-Ponce ◽  
Mireille Vega ◽  
Georgina C. Sandoval-Fabián ◽  
Edith Colunga-Urbina ◽  
Nagamani Balagurusamy ◽  
...  
Keyword(s):  
Free Amino ◽  
Water Soluble ◽  
Colorimetric Determination ◽  
Amino Groups ◽  
Chitin Derivatives

scholarly journals Effect of Hot Water Extracts of White Button Mushrooms on Human Aortic Endothelial Cells (HAEC) Exposed to Hyperglycemia (P06-085-19)

2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Keith Martin
Keyword(s):  
Basal Medium ◽  
Water Soluble ◽  
Hot Water ◽  
No Production ◽  
Aortic Endothelial Cells ◽  
Water Extracts ◽  
University Of Memphis ◽  
Funding Sources ◽  
Health Studies ◽  
Human Aortic Endothelial Cells

Abstract Objectives In the present study, we investigated the effects of WBM on aortic endothelium alone or in a hyperglycemic environment with or without insulin. Methods Sterile (0.22 um filtered) hot water extracts of WBM (Agaricus bisporus) were added to endothelial basal medium (5% v/v) alone or containing glucose (final concentration 600 mg/dl; 33.3 mM) and/or insulin (100 nM) for 24 hours. Results We show that WBM increased reactive oxygen species (ROS) levels by 2.5-fold (p < 0.05) compared to control cultures using the DCFH-DA assay, which was further increased 18% with insulin inclusion, but decreased by ∼20% in the presence of glucose with or without insulin. WBM also increased nitric oxide (NO) levels by 4-fold (p < 0.05) compared to control cultures, which was further increased by 3.5-fold in the presence of glucose (p < 0.05) suggesting possible potentiation. We noted no differences in NO production, compared to control cultures, with inclusion of insulin with or without glucose. Viability determined by MTT reduction, was not different between any of the groups. Conclusions The results suggest that water-soluble components of WBM may modulate ROS and NO production in a hyperglycemic microenvironment and potentially improve endothelial function, in part, via the potential vasorelaxation properties of NO. Funding Sources Internal Seed Grant, School of Health Studies, University of Memphis, Memphis, TN 38,152.

Collaborative Study of a Colorimetric Determination of Nitrate in Tobacco

1969 ◽  
Vol 52 (4) ◽  
pp. 756-759
Author(s):  
C James Rosene
Keyword(s):  
Sulfuric Acid ◽  
Standard Deviation ◽  
Systematic Error ◽  
Collaborative Study ◽  
Colorimetric Method ◽  
Water Soluble ◽  
Colorimetric Determination ◽  
Error Standard Deviation

Abstract A colorimetric method for determining water-soluble nitrate in tobacco was studied by 14 laboratories on eight Burley and two cigar filler tobacco samples with nitrate levels of 0.5–2.4%. In the method, ground tobacco is extracted with water and filtered, and an aliquot is then treated with 2,4-xylenol in sulfuric acid; then the resulting 6-nitro-2,4-xylenol is removed by distillation and measured spectrophotometrically at 450 µm. Results show that, althoughthe precision standard deviation among laboratories is generally acceptable, the systematic error standard deviation is unacceptably high. This study will be continued.

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