Estimation of the Mean Degree of Polymerization of Condensed Tannins from the Kernel and Shell of Carya illinoinensis by HPLC/MS and Spectrophotometric Methods

This study aimed to determine the concentration and composition of condensed tannins (CT) in different tissues of purple prairie clover (PPC; Dalea purpurea Vent.) at different maturities and to determine their protein-precipitating capacity. The compositions of CT were elucidated after thiolysis with benzyl mercaptan followed by high-performance liquid-chromatography (HPLC) and 1H–13C heteronuclear single quantum coherence (HSQC) NMR spectroscopy. The results indicated that PPC flowering heads contained the highest CT concentration. Purple prairie clover CT consisted mainly of epicatechin (EC) and epigallocatechin (EGC) subunits. CT in the leaves were composed of more EC and less EGC than CT in stems and flowering heads at both the early flowering (EF) and late flowering (LF) head stages. The mean degree of polymerization was the highest for CT in stems and increased with maturity. CT isolated from PPC leaves at the early flowering head stage exhibited the greatest biological activity in terms of protein precipitation. Overall, the CT in PPC were predominantly procyanidins and the concentration and composition varied among the plant tissues and with maturity.

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Polyphenolic profile and stilbene content of Albanian “Kallmet” monovarietal wine

OENO One ◽

10.20870/oeno-one.2018.52.2.2062 ◽

2018 ◽

Vol 52 (2) ◽

pp. 135-144 ◽

Cited By ~ 1

Author(s):

Anisa Peçuli ◽

Fabrice Lorenzini ◽

Mariglen Angjellari ◽

Sylvain Schnee ◽

Katia Gindro ◽

...

Keyword(s):

Condensed Tannins ◽

Phenolic Content ◽

Mean Value ◽

Degree Of Polymerization ◽

Anthocyanin Content ◽

Red Wines ◽

Grape Variety ◽

The Mean ◽

Red Grape ◽

Polyphenolic Profile

Aim: The aim of this work was to characterize the phenolic content of wines from the most promising autochthonous red grape variety in Albania, the Kallmet.Methods and results: To make this first survey, 16 commercial monovarietal Kallmet wines were analyzed with special attention to proanthocyanidin (condensed tannins), anthocyanin and stilbene composition. The average content of total proanthocyanidins in these wines was 3877 mgL-1 and the anthocyanin content averaged 242 mgL-1. The mean degree of polymerization (mDP) varied from 8 subunits in young wine to 31 subunits in 6-year-old wine, with a mean value of 14.5 subunits. The total free anthocyanin content ranged from 85 mgL-1 in old wine to 609 mgL-1 in young wine, with a mean value of 242.5 mgL-1. Trans-piceid was the most abundant stilbene (11 mgL-1), followed by trans-resveratrol (1.8 mgL-1). It was evidenced that cis-forms of resveratrol and piceid presented a lower content than their trans-forms. The ratio between piceid (glycoside form) and resveratrol (aglycone form) was 8.2, showing a similar stilbene pattern as in Mediterranean wines.Conclusions: Kallmet wines show proanthocyanidin polymerization characteristics and stilbene profiles very similar to red wines deriving from other varieties grown under warm climates.Significance and impact of the study: In spite of the strong interest in Kallmet grape, there is still a need for detailed studies to know the range of the different components of interest found in the produced wine.

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Use of Tannin-Containing Plants as Antimicrobials Influencing the Animal Health

The Iraqi Journal of Veterinary Medicine ◽

10.30539/ijvm.v45i2.1258 ◽

2022 ◽

Vol 45 (2) ◽

pp. 33-40

Author(s):

Mohammed M Dakheel ◽

Afnan A Al-Mnaser ◽

Jessica Quijada ◽

Martin J Woodward ◽

Caroline Rymer

Keyword(s):

Nutritional Quality ◽

Condensed Tannins ◽

Animal Health ◽

Degree Of Polymerization ◽

Gram Negative Bacteria ◽

Animal Feeding ◽

The Subject

The antimicrobial effects of diverse tannin-containing plants, particularly condensed tannins (CTs) produced from various plants, are the subject of this study. CT components can be determined using CT-specific procedures such the HCl-Butanol Acetone assay, Thiolysis reaction, and HPLC/MS analysis. These methods indicate CT contents, including mean degree of polymerization, the procyanidins and prodelphinidins ratio (PC/PD%), the isomers of trans- and cis-, and CT concentration. Tannin-containing plants possess antibacterial action, which can be attributed to their protein linkage technique, and tannin-type variations, particularly CTs extract and their PC/PD%. The effects of CT components on the development of Gram-positive and Gram-negative bacteria have been documented for their relative PC/PD%; this is regarded to be a key predictor of tannin characteristics in terms of antimicrobials. In conclusion, tannins, more specific CT compositions, have significant impacts on in vivo trials of animal productions and utilization of metabolites and fermentation in vitro experiments. These findings need further investigations to fully understand how CT-types act on animal feeding in terms of enhanced nutritional quality of animal diets, which may have implications for human and animal health.

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Zero order and area under curve spectrophotometric methods for determination of Levocetirizine in pharmaceutical formulation

International Journal of Advances in Scientific Research ◽

10.7439/ijasr.v1i6.2253 ◽

2015 ◽

Vol 1 (6) ◽

pp. 270

Author(s):

Audumbar Digambar Mali ◽

Ritesh Bathe ◽

Manojkumar Patil ◽

Ashpak Tamboli

Keyword(s):

Area Under The Curve ◽

Zero Order ◽

Pharmaceutical Dosage Forms ◽

Mean Values ◽

Spectrophotometric Methods ◽

Ich Guidelines ◽

Significant Difference ◽

Curve Method ◽

The Mean

Simple, fast and reliable spectrophotometric methods were developed for determination of Levocetirizine in bulk and pharmaceutical dosage forms. The solutions of standard and the sample were prepared in methanol. The quantitative determination of the drug was carried out using the zero order derivative values measured at 230 nm and the area under the curve method values measured at 227-234 nm (n=2). Calibration graphs constructed at their wavelengths of determination were linear in the concentration range of Levocetirizine using 5-25?g/ml (r=0.998 and r=0.999) for zero order and area under the curve spectrophotometric method. All the proposed methods have been extensively validated as per ICH guidelines. There was no significant difference between the performance of the proposed methods regarding the mean values and standard deviations. Developed spectrophotometric methods in this study are simple, accurate, precise and sensitive to assay of Levocetirizine in tablets.

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Adaptation of Color Reactions for Spectrophotometric Determination of Pitavastatin Calcium in Bulk Drugs and in Pharmaceutical Formulations

E-Journal of Chemistry ◽

10.1155/2007/628987 ◽

2007 ◽

Vol 4 (2) ◽

pp. 272-278 ◽

Cited By ~ 2

Author(s):

Marothu Vamsi Krishna ◽

Dannana Gowri Sankar

Keyword(s):

Cost Effective ◽

Pharmaceutical Formulations ◽

Reagent Blank ◽

Colored Complex ◽

Spectrophotometric Methods ◽

Experimental Parameters ◽

The Mean ◽

Pitavastatin Calcium ◽

Color Reactions

Three simple, sensitive and cost effective Spectrophotometric methods are described for the determination of pitavastatin calcium (PST) in bulk drugs and in pharmaceutical formulations. These methods are based on the oxidation of PST by ferric chloride in presence ofo-phenanthroline (Method A) or 2, 2’ bipyridyl (Method B) or potassium ferricyanide (Method C). The colored complex formed was measured at 510, 530 and 755 nm for method A, B and C respectively against the reagent blank prepared in the same manner. The optimum experimental parameters for the color production are selected. Beer’s law is valid with in a concentration range of 4-20 μg mL-1for method A, 7.5-37.5 μg mL-1for method B and 5 -25 μg mL-1for method C. For more accurate results, ringbom optimum concentration ranges are 5-18 μg mL-1for method A , 8.5-35.5 μg mL-1for method B and 6.0-23.0 μg mL-1for method C. The molar absorptivities are 3.55x104, 2.10x104and 3.10x104L mol-1cm-1. Where as sandell sensitivities are 0.024, 0.041 and 0.028 μg cm-22 for method A, B and C respectively. The mean percentage recoveries are 99.95 for method A, 101.35 for method B and 100.33 for method C. The developed methods were applied for the determination of PST in bulk powder and in the pharmaceutical formulations without any interference from tablet excipients.

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The State of Polydispersion of Hevea Latex. II.

Rubber Chemistry and Technology ◽

10.5254/1.3543274 ◽

1947 ◽

Vol 20 (2) ◽

pp. 409-415

Author(s):

J. H. E. Hessels

Keyword(s):

Particle Size ◽

Surface Area ◽

Degree Of Polymerization ◽

The State ◽

Rubber Industry ◽

Mean Particle Size ◽

Degree Of Dispersion ◽

The Mean ◽

In The Beginning

Abstract The influence of the degree of dispersion in latex on the composition and properties of the rubber was studied in detail by means of a series of latices, the mean particle size of which ranged from 1.1 to 0.15µ in diameter. These fractions were first obtained by centrifugation of preserved latex, and the degree of distribution was measured by photomicrographic analysis and by sedimentation. This method of fractionation yields latices and rubbers with compositions which differ widely. With decrease in the size of the particles, their surface area per unit of rubber increases, and the percentage of nonrubber components which is adsorbed irreversibly or which is dissolved in the serum increases greatly. On the contrary, the degree of polymerization decreases with decrease in the diameter of the particles. This may be explained by the fact that, in the beginning, the polymerization of the globules is relatively low, and that it progresses under the influence of a catalyst present in the serum. In brief, then, systematic dispersoidal analysis of Hevea latex is of prime importance in the plantation rubber industry.

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Methods for Determining the Degree of Polymerization of Condensed Tannins: A New 1H-NMR Procedure Applied to Cider Apple Procyanidins

Plant Polyphenols 2 ◽

10.1007/978-1-4615-4139-4_11 ◽

1999 ◽

pp. 211-222 ◽

Cited By ~ 6

Author(s):

Sylvain Guyot ◽

Christine Le Guernevé ◽

Nathalie Marnet ◽

Jean-François Drilleau

Keyword(s):

1H Nmr ◽

Condensed Tannins ◽

Degree Of Polymerization

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Impact of Eutectic Solvents Utilization in the Microwave Assisted Extraction of Proanthocyanidins from Grape Pomace

Molecules ◽

10.3390/molecules27010246 ◽

2021 ◽

Vol 27 (1) ◽

pp. 246

Author(s):

Rodrigo T. Neto ◽

Sónia A. O. Santos ◽

Joana Oliveira ◽

Armando J. D. Silvestre

Keyword(s):

Lactic Acid ◽

Choline Chloride ◽

Extraction Yield ◽

Degree Of Polymerization ◽

Grape Pomace ◽

Microwave Assisted Extraction ◽

Microwave Assisted ◽

Assisted Extraction ◽

Effective Combination ◽

The Mean

The extraction of proanthocyanidins (PACs), despite being an important and limiting aspect of their industrial application, is still largely unexplored. Herein, the possibility of combining eutectic solvents (ESs) with microwave assisted extraction (MAE) in the extraction of PACs from grape pomace (GP) is explored, aiming to improve not only the extraction yield but also the mean degree of polymerization (mDP). The combination of choline chloride with lactic acid was shown to be the most effective combination for PACs extraction yield (135 mgPAC/gGP) and, despite the occurrence of some depolymerization, also enabled us to achieve the highest mDP (7.13). Additionally, the combination with MAE enabled the process to be completed in 3.56 min, resulting in a considerably reduced extraction time.

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Three Spectrophotometric Methods for Quantitative Analysis of Duloxetine in Presence of its Toxic Impurity: 1-Naphthol

Journal of AOAC International ◽

10.1093/jaoacint/qsz032 ◽

2020 ◽

Vol 103 (4) ◽

pp. 972-979 ◽

Cited By ~ 1

Author(s):

Ibrahim A Naguib ◽

Nessreen S Abdelhamid ◽

Basma H Anwar ◽

Maimana A Magdy

Keyword(s):

Pharmaceutical Formulations ◽

Control Analysis ◽

Aquatic Life ◽

Spectrophotometric Methods ◽

Duloxetine Hydrochloride ◽

Ich Guidelines ◽

Mean Centering ◽

Absorbance Difference ◽

The Mean

Abstract Background Duloxetine hydrochloride (DUL) is a drug used to treat depression and anxiety. 1-Naphthol is a potential toxic impurity of DUL, as it causes hepatotoxicity in humans, and it is harmful to aquatic life. Objective Three simple, selective, rapid, accurate and precise methods were developed and validated according to International Conference on Harmonization (ICH) guidelines with respect to linearity, accuracy, precision and selectivity for analysis of duloxetine hydrochloride (DUL) in the presence of its potential toxic impurity 1-Naphthol in different laboratory-prepared mixtures and pharmaceutical formulations. Methods Method (A) is the first derivative of the ratio spectra spectrophotometric (1DD) method which allows determination of DUL at 251 nm and 1-Naphthol at 305.2 nm without interference from each other. Method B (dual wavelength) means that two different wavelengths were chosen to each drug, where the absorbance difference at these two wavelengths is equal to zero to the second drug. The chosen two wavelengths for DUL were 221.4 nm and 235.6, where the absorbance difference for 1-naphthol at these two wavelengths was equal to zero. While the chosen wavelengths for 1-naphthol were 247.8 nm and 297 nm, where the absorbance difference for DUL at these two wavelengths was equal to zero. Method (C) is the mean centering of ratio spectra spectrophotometric (MCR) method, which depends on measuring the mean centered values of ratio spectra of both DUL and 1-Naphthol at 226 nm. Results These methods were validated and agreed with the requirements of ICH guidelines with respect to linearity, accuracy, precision and selectivity. Conclusions The results indicate the ability of developed methods to be used for routine quality control analysis of DUL in bulk and pharmaceutical formulations in the presence of its potential impurity 1-Naphthol.

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Determination of Inulin in Foods

Journal of AOAC International ◽

10.1093/jaoac/83.3.675 ◽

2000 ◽

Vol 83 (3) ◽

pp. 675-678 ◽

Cited By ~ 12

Author(s):

Breda Simonovska

Keyword(s):

Standard Deviation ◽

Oxalic Acid ◽

Thin Layer ◽

Degree Of Polymerization ◽

Test Solution ◽

Boiling Water Bath ◽

Before And After ◽

The Mean ◽

The Difference

Abstract A method was developed for determining fructan inulin in various foods (yogurts, honey cakes, chocolates). Warm water was applied for extraction of samples, and mono- and dissacharides were determined by a thin-layer chromatographic densitometric method. A portion of the test solution was hydrolyzed 30 min with 1% oxalic acid in a boiling water bath. Fructose was determined in the hydrolysate. The amount of inulin in a sample was calculated as the difference between the amount of fructose in the sample before and after hydrolysis. The fructose from sucrose formed during the hydrolysis was also considered. The mean recovery from yogurt fortified with 4% inulin was 95.5 ± 4.5% (mean ± standard deviation); from honey cakes extract fortified with 10% inulin, 97.3 ± 5.5%; and from chocolate extract fortified with 30% inulin, 98.6 ± 6.6% (6 replicates in all cases). Determination of glucose is not necessary for analyzing fructans with the composition expressed shortened to GFn−1 (G, glucose; F, fructosyl) with the average degree of polymerization 8 ≤ n ≤ 15.

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