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Spectrophotometric estimation

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https://www.readbyqxmd.com/read/28521827/antioxidant-activity-acetylcholinesterase-inhibitory-potential-and-phytochemical-analysis-of-sarcocephalus-latifolius-sm-bark-used-in-traditional-medicine-in-sudan
#1
Alsiddig Osama, Sufyan Awadelkarim, Amna Ali
BACKGROUND: Sarcocephalus latifolius is used as a traditional medicine for curing many diseases in Sudan. The main objective of the current study was to determine the antioxidant activity and acetylcholinesterase inhibition (AChEI) of S. latifolius, and to estimate its total phenolic and flavonoid contents. METHODS: Antioxidant activity of the tested plant extracts was carried out by determining their ability to scavenge the 2,2-diphenyl-1-picryl hydrazyl (DPPH) free radical...
May 18, 2017: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/28505111/effects-of-mead-wort-heat-treatment-on-the-mead-fermentation-process-and-antioxidant-activity
#2
Sławomir Czabaj, Joanna Kawa-Rygielska, Alicja Z Kucharska, Jarosław Kliks
The effects of mead wort heat treatment on the mead fermentation process and antioxidant activity were tested. The experiment was conducted with the use of two different honeys (multiflorous and honeydew) collected from the Lower Silesia region (Poland). Heat treatment was performed with the use of a traditional technique (gently boiling), the more commonly used pasteurization, and without heat treatment (control). During the experiment fermentation dynamics were monitored using high performance liquid chromatography with refractive index detection (HPLC-RID)...
May 14, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28501974/proteolytic-activities-in-cortex-of-apical-parts-of-vicia-faba-ssp-minor-seedling-roots-during-kinetin-induced-programmed-cell-death
#3
Andrzej Kaźmierczak, Magdalena Doniak, Anita Kunikowska
Programmed cell death (PCD) is a crucial process in plant development. In this paper, proteolytically related aspects of kinetin-induced PCD in cortex cells of Vicia faba ssp. minor seedlings were examined using morphological, fluorometric, spectrophotometric, and fluorescence microscopic analyses. Cell viability estimation after 46 μM kinetin treatment of seedling roots showed that the number of dying cortex cells increased with treatment duration, reaching maximum after 72 h. Weight of the apical root segments increased with time and was about 2...
May 13, 2017: Protoplasma
https://www.readbyqxmd.com/read/28475326/spectrophotometric-analysis-of-phenolic-compounds-in-grapes-and-wines
#4
Jose Luis Aleixandre-Tudo, Astrid Buica, Helene Nieuwoudt, Jose Luis Aleixandre, Wessel du Toit
Phenolic compounds are of crucial importance for red wine color and mouthfeel attributes. A large number of enzymatic and chemical reactions involving phenolic compounds take place during winemaking and aging. Despite the large number of published analytical methods for phenolic analyses, the values obtained may vary considerably. In addition, the existing scientific knowledge needs to be updated, but also critically evaluated and simplified for newcomers and wine industry partners. The most used and widely cited spectrophotometric methods for grape and wine phenolic analysis were identified through a bibliometric search using the Science Citation Index-Expanded (SCIE) database accessed through the Web of Science (WOS) platform from Thompson Reuters...
May 16, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28460317/simultaneous-determination-of-the-brand-new-two-drug-combination-for-the-treatment-of-hepatitis-c-sofosbuvir-ledipasvir-using-smart-spectrophotometric-methods-manipulating-ratio-spectra
#5
Maya S Eissa
In this work, various sensitive and selective spectrophotometric methods were first introduced for the simultaneous determination of sofosbuvir and ledipasvir in their binary mixture without preliminary separation. Ledipasvir was determined simply by zero-order spectrophotometric method at its λmax=333.0nm in a linear range of 2.5-30.0μg/ml without any interference of sofosbuvir even in low or high concentrations and with mean percentage recovery of 100.05±0.632. Sofosbuvir can be quantitatively estimated by one of the following smart spectrophotometric methods based on ratio spectra developed for the resolution of the overlapped spectra of their binary mixture; ratio difference spectrophotometric method (RD) by computing the difference between the amplitudes of sofosbuvir ratio spectra at 228nm and 270nm, first derivative (DD(1)) of ratio spectra by measuring the sum of amplitude of trough and peak at 265nm and 277nm, respectively, ratio subtraction (RS) spectrophotometric method in which sofosbuvir can be successfully determined at its λmax=261...
April 20, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28452015/biodegradation-of-ciprofloxacin-by-white-rot-fungus-pleurotus-ostreatus
#6
Sushil Kumar Singh, Robinka Khajuria, Loveleen Kaur
Unrestricted and reckless use of antibiotics has resulted in their accumulation in environment. This, in turn, has led to the emergence of multiple drug-resistant microbes. The present study focuses on degradation of ciprofloxacin (CIP) by an edible white rot fungus Pleurotus ostreatus. Effect of CIP was determined on radial growth and biomass of P. ostreatus. Titrimetric and spectrophotometric assays were carried out to assess the degrading potential of P. ostreatus towards CIP. It was found that CIP has a stimulatory effect on growth and enzyme activity of P...
May 2017: 3 Biotech
https://www.readbyqxmd.com/read/28443587/role-of-trace-elements-for-oxidative-status-and-quality-of-human-sperm
#7
Galina Nenkova, Lubomir Petrov, Albena Alexandrova
BACKGROUND: Oxidative stress affects negatively the sperm quality. For maintaining the pro/antioxidative balance, some metal ions (e.g. copper, zinc, iron, selenium), which are co-factors of the antioxidant enzymes, are essential. However, iron and copper could act as prooxidants inducing oxidative damage of spermatozoa. AIMS: This study aims to reveal a possible correlation between the concentrations of some metal ions (iron, copper, zinc, and selenium) in human seminal plasma, oxidative stress, assessed by malondialdehyde (MDA) and total glutathione (tGSH) levels, and semen quality, assessed by the parameters count, motility, and morphology...
April 6, 2017: Balkan Medical Journal
https://www.readbyqxmd.com/read/28423063/vitamin-d-status-and-its-association-with-insulin-resistance-among-type-2-diabetics-a-case-control-study-in-ghana
#8
Linda Ahenkorah Fondjo, William K B A Owiredu, Samuel Asamoah Sakyi, Edwin Ferguson Laing, Michael Acquaye Adotey-Kwofie, Enoch Odame Antoh, Eric Detoh
BACKGROUND: Vitamin D plays a major role in physiological processes that modulate mineral metabolism and immune function with probable link to several chronic and infectious conditions. Emerging data suggests a possible influence of vitamin D on glucose homeostasis. This study sought to provide preliminary information on vitamin D status among Ghanaian type 2 diabetics and assessed its association with glucose homeostasis. METHODS: In a case control study, 118 clinically diagnosed Type 2 Diabetes Mellitus (T2DM) patients attending Diabetic Clinic at the Nkawie Government Hospital were enrolled between October and December 2015...
2017: PloS One
https://www.readbyqxmd.com/read/28414560/aloe-arborescens-polysaccharides-in-vitro-immunomodulation-and-potential-cytotoxic-activity
#9
Jilan A Nazeam, Haidy A Gad, Ahmed Esmat, Hala M El-Hefnawy, Abdel-Naser B Singab
Different polysaccharides were isolated from the leaves of Aloe arborescens using the gradient power of hydrogen followed by antitumor and immunomodulatory assay. The total polysaccharide content of different fractions, water-soluble polysaccharide (WAP), acid-soluble polysaccharide (ACP), and alkaline-soluble polysaccharide (ALP), was estimated using a phenol-sulfuric acid spectrophotometric method. WAP possessed a higher content of mannose and glucose than either ACP or ALP. In vitro antitumor activity was investigated in three different cancer cell lines, and in vitro immunomodulatory potential was assessed through phagocytosis and lymphocyte transformation assay...
May 2017: Journal of Medicinal Food
https://www.readbyqxmd.com/read/28407934/organophosphorus-pesticides-determination-by-novel-hplc-and-spectrophotometric-method
#10
Dave Harshit, Kothari Charmy, Patel Nrupesh
The present work describes a novel HPLC and UV-spectrophotometric method for the simultaneous estimation of chlorpyrifos and prophenofos in vegetables and fruits. In UV method, the absorbance of chlorpyrifos and prophenofos was measured at wavelength 277nm and 289nm respectively and quantitation was carried out by first order derivative method. The calibration curve for chlorpyriphos and prophenofos was found to be linear in the range of 6-16μg/mL with correlation coefficient 0.9979 and 0.9993 respectively...
September 1, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28377238/characterization-of-the-interaction-of-glycyrrhizin-and-glycyrrhetinic-acid-with-bovine-serum-albumin-by-spectrophotometric-gradient-flow-injection-titration-technique-and-molecular-modeling-simulations
#11
Firouzeh Manouchehri, Yahya Izadmanesh, Jahan B Ghasemi
In this research, the interactions of glycyrrhizin (GL) and glycyrrhetinic acid (GA) with bovine serum albumin (BSA) have been investigated by the novel method of spectrophotometric- gradient flow injection titration technique. The hard-modeling multivariate approach to binding was used for calculation of binding constants and estimation of concentration-spectral profiles of equilibrium species. The stoichiometric ratio of binding was estimated using eigenvalue analysis. Results showed that GL and GA bind BSA with overall binding constants of KGL-BSA=3...
April 1, 2017: International Journal of Biological Macromolecules
https://www.readbyqxmd.com/read/28376720/dynamic-changes-of-paraoxonase-1-activity-towards-paroxon-and-phenyl-acetate-during-coronary-artery-surgery
#12
Anna Wysocka, Marek Cybulski, Henryk Berbeć, Andrzej Wysokiński, Janusz Stążka, Jadwiga Daniluk, Tomasz Zapolski
BACKGROUND: Serum paraoxonase 1 (PON1), an enzyme associated with high - density lipoproteins (HDL) particles, inhibits the oxidation of serum lipoproteins and cell membranes. PON1 activity is lower in patients with atherosclerosis and in inflammatory diseases. The systemic inflammatory response provoked during cardiopulmonary bypass grafting may contribute to the development of postoperative complications. The aim of the present study was to estimate the dynamic changes in paraoxonase 1 (PON1) activity towards paraoxon and phenyl acetate during and after coronary artery surgery...
April 4, 2017: BMC Cardiovascular Disorders
https://www.readbyqxmd.com/read/28363541/estimation-of-uronic-acids-using-diverse-approaches-and-monosaccharide-composition-of-alkali-soluble-polysaccharide-from-vitex-negundo-linn
#13
Pradeep Kumar, Vineet Kumar
Vitex negundo L. is one of the most important species in traditional system of medicine to cure various ailments. Alkali soluble polysaccharide (ASP) from V. negundo stems was isolated and purified in 0.61% yield. Complete hydrolysis of ASP followed by paper chromatography and GLC analysis indicated the presence of l-rhamnose, l-arabinose, d-xylose, d-galactose and d-glucose in mole percent of 1.28, 2.25, 73.49, 8.08, 8.11 along with 2.48 d-galacturonic acid and 4.27 d-glucuronic acid. Uronic acids were also estimated by spectrophotometric methods using carbazole, m-hydroxydiphenyl and 3, 5-dimethyl phenol (DMP) as colorimetric reagents...
June 1, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28341986/enhancing-effectiveness-of-capillary-electrophoresis-as-an-analytical-tool-in-the-supramolecular-acidity-modification
#14
Paweł Mateusz Nowak, Michał Woźniakiewicz, Magdalena Janus, Paweł Kościelniak
A strategic modification of acidity (pK a values) by the non-covalent host-guest interactions is one of the most promising concepts in current supramolecular chemistry. This work is aimed at enhancing the effectiveness of capillary electrophoresis (CE) in determination of pK a shifts caused by such interactions and their thermal dependencies crucial in a deep thermodynamic description. We show how to (i) minimize the systematic errors related to Joule heating, (ii) minimize the influence of a voltage ramp time, (iii) speed up pK a shift identification and estimation, (iv) interpret thermal effects related to two overlapped dynamic equilibria, and (v) determine pK a shifts by an alternative spectrophotometric method (CE-DAD)...
May 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28317713/a-validated-fast-difference-spectrophotometric-method-for-5-hydroxymethyl-2-furfural-hmf-determination-in-corn-syrups
#15
Jucimara Kulek de Andrade, Camila Kulek de Andrade, Emy Komatsu, Hélène Perreault, Yohandra Reyes Torres, Marcos Roberto da Rosa, Maria Lurdes Felsner
Corn syrups, important ingredients used in food and beverage industries, often contain high levels of 5-hydroxymethyl-2-furfural (HMF), a toxic contaminant. In this work, an in house validation of a difference spectrophotometric method for HMF analysis in corn syrups was developed using sophisticated statistical tools by the first time. The methodology showed excellent analytical performance with good selectivity, linearity (R(2)=99.9%, r>0.99), accuracy and low limits (LOD=0.10mgL(-1) and LOQ=0.34mgL(-1))...
August 1, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28315620/3-e-acridin-9-ylmethylidene-amino-1-substituted-thioureas-and-their-biological-activity
#16
Michal Bečka, Mária Vilková, Othman Salem, Jana Kašpárková, Viktor Brabec, Mária Kožurková
This paper describes the synthesis of a novel series of acridine thiosemicarbazones through a two-step reaction between various isothiocyanates and hydrazine followed by treatment with acridin-9-carbaldehyde. The properties of this series of seven new derivatives are studied using NMR and biochemical techniques, and the DNA-binding properties of the compounds are determined using spectrophotometric studies (UV-vis absorption, fluorescence, and circular/linear dichroism) and viscometry. The binding constants K are estimated as being in the range of 2...
March 8, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28303123/trichoderma-asperellum-t42-and-pseudomonas-fluorescens-okc-enhances-resistance-of-pea-against-erysiphe-pisi-through-enhanced-ros-generation-and-lignifications
#17
Jai S Patel, Ravindra N Kharwar, Harikesh B Singh, Ram S Upadhyay, Birinchi K Sarma
Plant signaling mechanisms are not completely understood in plant-fungal biotrophic pathogen interactions. Further how such interactions are influenced by compatible rhizosphere microbes are also not well-studied. Therefore, we explored the pea-Erysiphe pisi (obligate biotroph) system to understand the interaction and applied compatible rhizospheric bio-agents Trichoderma asperellum (T42) and Pseudomonas fluorescens (OKC) singly or in combination to assess their influence on the host while under the pathogen challenge...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28290364/estimation-of-kinetic-parameters-of-anthocyanins-and-color-degradation-in-vitamin-c-fortified-cranberry-juice-during-storage
#18
Sunisa Roidoung, Kirk D Dolan, Muhammad Siddiq
Color degradation in cranberry juice during storage is the most common consumer complaint. To enhance nutritional quality, juice is typically fortified with vitamin C. This study determined effect of gallic acid, a natural antioxidant, for the preservation of anthocyanins (ACYs) and color, and estimated kinetics of ACYs and color degradation. Juice, fortified with 40-80mg/100mL vitamin C and 0-320mg/100mL gallic acid, was pasteurized at 85°C for 1min and stored at 23°C for 16days. Total monomeric anthocyanins and red color intensity were evaluated spectrophotometrically and data were used to determine degradation rate constants (k values) and order of reaction (n) of ACYs and color...
April 2017: Food Research International
https://www.readbyqxmd.com/read/28282223/analytical-methods-for-metformin-estimation
#19
Durgawati Patel, Puspendra Kumar, Swapnil Sharma, Jaya Dwivedi
Metformin is a widely prescribed oral anti-hyperglycemic agent used in the management of non-insulin dependent diabetes mellitus (NIDDM) or type II diabetes. This article accentuates various analytical methods viz. HPLC, HPTLC, spectrophotometric, electrochemical, capillary electrophoresis and LC-MS for the estimation of metformin in pharmaceutical formulations and in biological matrices.
March 10, 2017: Critical Reviews in Analytical Chemistry
https://www.readbyqxmd.com/read/28275214/investigation-of-drug-polymer-compatibility-using-chemometric-assisted-uv-spectrophotometry
#20
Amir Ibrahim Mohamed, Amr Mohamed Elsayed Abd-Motagaly, Osama A A Ahmed, Suzan Amin, Alaa Ibrahim Mohamed Ali
A simple chemometric-assisted UV-spectrophotometric method was used to study the compatibility of clindamycin hydrochloride (HC1) with two commonly used natural controlled-release polymers, alginate (Ag) and chitosan (Ch). Standard mixtures containing 1:1, 1:2, and 1:0.5 w/w drug-polymer ratios were prepared and UV scanned. A calibration model was developed with partial least square (PLS) regression analysis for each polymer separately. Then, test mixtures containing 1:1 w/w drug-polymer ratios with different sets of drug concentrations were prepared...
January 16, 2017: Pharmaceutics
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