scholarly journals Determination of polyphenol and EGCG in tea and tea products by UV-VIS and HPLC methods

2018 ◽  
Vol 1 (1) ◽  
pp. 8-12
Author(s):  
Ngoc Mai Pham Thi ◽  
Binh Le Thai ◽  
Dong Pham Huy ◽  
Tuyet Nhung Nguyen Thi ◽  
Duc Pham Tien ◽  
...  
Keyword(s):  
Active Ingredient ◽  
Analytical Methods ◽  
Hplc Method ◽  
Total Phenol ◽  
Total Polyphenol ◽  
Active Substances

Tea and tea products have been known and used for long and became a tradional culture in many countries in the world, including Vietnam. The quality of tea depends on the concentrations of typical active substances such as polyphenol groups and their active substances (EGCG, ECG, catechin,…). Therefore, study of analytical methods to determine these active substances is necessary to evaluate the quality of tea and tea products. In this study, UV-Vis method was selected to determine total polyphenol and HPLC method was selected to determine the main active ingredient of polyphenol group EGCG. The limit of detections are 0.12 mg/g and 0.064 mg/g for total polyphenol and EGCG, respectively. These methods were applied to determine the concentrations of total phenol and EGCG in 10 samples of tea and tea products. Results show that the concentrations of total phenol and EGCG vary significantly among samples, but there is a certain relationship between the concentration of total phenol and EGCG in each sample.

scholarly journals Development of an integrated approach to assessing the sanitary quality of feed for fur-bearing animals

2020 ◽  
Vol 17 ◽  
pp. 00154
Author(s):  
Sergei V. Beketov ◽  
Alexander V. Kozlov ◽  
Oleg V. Gorbunov ◽  
Natalia A. Golovacheva
Keyword(s):  
Adenosine Triphosphate ◽  
Analytical Methods ◽  
Bacterial Contamination ◽  
Integrated Approach ◽  
Total Volatile ◽  
Feed Mixture ◽  
Indirect Determination

In the article a brief description of new analytical methods for the indirect determination of bacterial contamination of the finished feed mixture and dry feed for fur-bearing animals by the level of adenosine triphosphate (ATP) and ammonia are provided. The prospects for their use in comparison with the method of analysis of total volatile nitrogen are assessed.

scholarly journals A review of analytical methods for the determination of four new phosphodiesterase type 5 inhibitors in biological samples and pharmaceutical preparations

2013 ◽  
Vol 49 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Cristiane Franco Codevilla ◽  
Tamara dos Santos Castilhos ◽  
Ana Maria Bergold
Keyword(s):  
Erectile Dysfunction ◽  
Analytical Methods ◽  
Pharmaceutical Preparations ◽  
Pharmaceutical Formulations ◽  
Sexual Problem ◽  
Phosphodiesterase Type 5 Inhibitors ◽  
Phosphodiesterase Type 5 Inhibitor ◽  
Phosphodiesterase Type

The introduction of oral phosphodiesterase type 5 inhibitor therapy in 1998 revolutionized the treatment of erectile dysfunction. Erectile dysfunction is the most common sexual problem in men. It often has a profound effect on intimate relationships and quality of life. The analysis of pharmaceuticals is an important part of the drug development process as well as for routine analysis and quality control of commercial formulations. Whereas the determination of sildenafil citrate, vardenafil and tadalafil are well documented by a variety of methods, there are few publications about the determination of udenafil, lodenafil carbonate, mirodenafil and avanafil. The paper presents a brief review of the action mechanism, adverse effects, pharmacokinetics and the most recent analytical methods that can determine drug concentration in biological matrices and pharmaceutical formulations of these four drugs.

scholarly journals DETERMINATION OF TECHNOLOGICAL PARAMETERS AND INDICATORS OF THE QUALITY OF NEW HERBAL COLLECTION

2018 ◽  
Vol 6 ◽  
pp. 61-68 ◽  
Author(s):  
Anna Kriukova ◽  
Inna Vladymyrova
Keyword(s):  
Rheumatic Diseases ◽  
Maximum Yield ◽  
Biologically Active ◽  
Raw Material ◽  
Concomitant Treatment ◽  
Technological Parameters ◽  
Anti Inflammatory ◽  
Active Substances

Rheumatic diseases include more than 1000 nosological forms, among which the highest incidence is osteoarthritis, rheumatoid arthritis and osteoporosis. The predominantly advanced age, the presence of comorbid diseases, the duration of the course of the disease and the need for concomitant treatment complicate the conduct of anti-inflammatory and analgesic therapy in such patients. Herbal medicines, in particular in the form of doses, due to the mildness of the action and the absence of significant side effects, can be used in the complex therapy of the acute period of rheumatic diseases, as well as for the prevention of relapse. The aim of the presented work was to develop the composition, technology and determination of the quality indices of herbal collection, which reveals analgesic and anti-inflammatory properties and can be used for the prophylaxis and auxiliary therapy of a number of conditions in rheumatology. Materials and methods. In the course of research, the methods used in the State Pharmacopoeia of Ukraine 2.0 (SPHU) were used. Results. As a result of the analysis of literary data and our own experimental studies on the chemical composition and pharmacological activity of certain types of medicinal plant material, we have developed herbal collection that is recommended for the treatment and prevention of rheumatic diseases of the joints. Studies have been conducted on the development of quality collection indicators, which guarantee the effectiveness, safety, reproducibility of the imposed collection. The basic technological parameters of the raw material are determined: specific, bulk and volume mass, porosity, degree, degree of shredding. In order to prevent uneven mixing, an optimal degree of grinding of the raw material of the investigated collection, which ranges from 0.20 mm to 0.35 mm, is established, which allows obtaining a homogeneous mixture and contributes to the maximum yield of extractive and active substances. A series of experimental works aimed at studying the influence of the method of infusion (for 15, 30, 45, 60 minutes and until complete cooling) on the quality of the collected water extracts from the collection was conducted. The optimal method for setting the collection for 60 minutes is the best, since the content of extractives and flavonoids in the aqueous extract was highest and amounted to 49.57±0.52 % and 0.52±0.03 % respectively. Conclusions. The composition of the herbal drug was developed: Harpagophyti radiх, Sophoraе alabastra, Valvae fructus Phaseoli vulgaris, Polygoni avicularis herba with the following ratio of components 50: 20: 20:10. The technological parameters of the raw material are studied: specific, volumetric and bulk mass, porosity, singularity of raw materials. The optimum degree of shredding of raw material is established, which helps to maximally remove biologically active substances and extractives. Experimental way is determined the optimal mode of collection, which can be recommended to the consumer to obtain the maximum therapeutic effect.

scholarly journals Determination of Keeping Quality of Tea using Silica Desiccant

2019 ◽  
Vol 8 (3) ◽  
pp. 1534-1536
Keyword(s):  
Silica Gel ◽  
Water Extract ◽  
Quality Parameters ◽  
Low Density ◽  
Chemical Parameters ◽  
Total Polyphenol ◽  
Keeping Quality ◽  
Poly Ethylene

A study was carried out to find out the effect of silica gel on keeping quality of tea. CTC-SRD grade teas each at 250 g were packed in low density poly ethylene pouches with a small pouch containing silica gel (10 g). Another set of samples were packed in low density poly ethylene packing material without silica gel. From sealed pouches, every month one pouch was taken and analysed for their moisture and quality parameters such as theaflavin, thearubigin, high polymerised substance, total liquor colour and biochemical parameters such as total polyphenol, total catechin, water extract and amino acid. Studies conducted after fourteen month indicated that the moisture content increased in teas packed in LDPE alone and it was less in teas packed in LDPE with silica gel. The level of theaflavin content decreased by 24.01% in teas packed LDPE alone and 17.92 % in LDPE with silica gel respectively. Bio chemical parameters decreased in teas packed in LDPE when compared to LDPE with silica gel. The study reveals that silica gel is useful in maintaining the keeping quality of tea.

scholarly journals Analytical Method Validation and Formula Optimization of Topical Nanoemulsion Formulation Containing Resveratrol

2021 ◽  
Author(s):  
Christofori Maria Ratna Rini Nastiti ◽  
Florentinus Dika Octa Riswanto
Keyword(s):  
Limit Of Detection ◽  
Aqueous Solubility ◽  
Reversed Phase ◽  
Hplc Method ◽  
Optimum Composition ◽  
Analytical Method Validation ◽  
Limit Of Quantitation ◽  
Diabetic Wounds

Resveratrol (RSV), a natural lipophilic phytoalexin, was reported as an antioxidant and anti-inflammatory agent, which has the potential to cure diabetic wounds. However, several studies suggested the limitation of RSV, such as poor aqueous solubility, poor stability, and poor oral bioavailability. To overcome the issues, RSV was formulated as a topical nanoemulsion. It is important to ensure the quality of the dosage form by evaluating RSV load in the nanoformulation and optimizing the formula. A reversed-phase HPLC method was developed and validated prior to the load determination of RSV in the nanoemulsion formulation. The composition of triacetin-eugenol, Kolliphor® RH 40, and Transcutol® was further optimized by employing a Box-Behnken Design (BBD) to achieve the optimum composition with expected viscosity and RSV load. The HPLC method for determining RSV load was successfully validated for parameters of selectivity with the resolution of 8.487, linearity and range (r = 0.9979), precision (0.12% of RSD), accuracy (109–110% of recovery), the limit of detection (0.574 µg/mL), and limit of quantitation (1.740 µg/mL). The result of formula optimization was promising, showing the optimum composition of triacetin-eugenol, Kolliphor® RH 40, and Transcutol® at 4.44 g, 30.97 g, and 11.39 g, respectively.

scholarly journals Comprehensive Assessment of Flow and Other Analytical Methods Dedicated to the Determination of Zinc in Water

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3914
Author(s):  
Paweł Kościelniak ◽  
Paweł Mateusz Nowak ◽  
Joanna Kozak ◽  
Marcin Wieczorek
Keyword(s):  
Analytical Chemistry ◽  
Green Chemistry ◽  
Analytical Method ◽  
Analytical Methods ◽  
Green Analytical Chemistry ◽  
General Quality ◽  
Analytical Strategies ◽  
High Degree

An original strategy to evaluate analytical procedures is proposed and applied to verify if the flow-based methods, generally favorable in terms of green chemistry, are competitive when their evaluation also relies on other criteria. To this end, eight methods for the determination of zinc in waters, including four flow-based ones, were compared and the Red–Green–Blue (RGB) model was exploited. This model takes into account several features related to the general quality of an analytical method, namely, its analytical efficiency, compliance with the green analytical chemistry, as well as practical and economic usefulness. Amongst the investigated methods, the best was the flow-based spectrofluorimetric one, and a negative example was that one involving a flow module, ICP ionization and MS detection, which was very good in analytical terms, but worse in relation to other aspects, which significantly limits its overall potential. Good assessments were also noted for non-flow electrochemical methods, which attract attention with a high degree of balance of features and, therefore, high versatility. The original attempt to confront several worldwide accepted analytical strategies, although to some extent subjective and with limitations, provides interesting information and indications, establishing a novel direction towards the development and evaluation of analytical methods.

scholarly journals Development of stability indicating method for quality assessment of African Albendazole tablets

2021 ◽  
Vol 319 ◽  
pp. 01084
Author(s):  
Amine Hssaine ◽  
Miloud El Karbane ◽  
Mohamed Azougagh ◽  
Imad Eddine Houti ◽  
Brahim Benaji
Keyword(s):  
Gradient Elution ◽  
The United States ◽  
Hplc Method ◽  
Stability Indicating ◽  
Stability Indicating Method ◽  
The Stability ◽  
Physical And Chemical ◽  
States Pharmacopeia

In order to assess the quality of Albendazole tablets (Alb) sampled in three countries from West Africa, several physical and chemical tests were performed on tablets at normal conditions. A simple and economic HPLC method has been developed, validated and used for the simultaneous determination of Albendazole (Alb) content, as well as its impurities and the uniformity of its content. The stability-indicating HPLC method was performed on a Symmetry C18-5µm 250 mm × 4.6 mm column with a gradient elution using a mobile phase composed of acetonitrile and sodium acetate buffer. The flow rate was set at 1 mL.min−1 and the eluent was monitored at 295nm. The method was validated for specificity, linearity, accuracy, precision, robustness and detection and quantification limits, in accordance with International Conference on Harmonisation Quality 2 (ICH Q2) guidelines. This method was performed on different Alb samples (originals and generics) products collected from Senegal, Niger and Mali. The obtained results showed that, the contents of the generic tablets from Niger and Mali comply with the United States Pharmacopeia (USP) monograph acceptance criteria. However, more than 20% of the generic tablets don’t meet the USP monograph impurity limits. In conclusion, the described analytical method is simple, sensitive and accurate. Thus, it could be useful for manufacturing and quality control assays.

scholarly journals Quantitative determination of the faradiol esters in marigold flowers and extracts

2003 ◽  
Vol 71 (2) ◽  
pp. 121-128 ◽  
Author(s):  
Gottfried Reznicek ◽  
Karin Zitterl-Eglseer
Keyword(s):  
Quantitative Determination ◽  
Hplc Analysis ◽  
Pharmaceutical Preparations ◽  
Hplc Method ◽  
Anti Inflammatory

An HPLC method is introduced for the precise quantitative determination of the anti-inflammatory active faradiol esters from marigold flowers and extracts. After a prepurification the HPLC analysis allows the proof of the quality of marigold flowers or C02-extracts used for pharmaceutical preparations.

scholarly journals DETERMINATION OF AMINO ACIDS AND SUGARS CONTENT IN ANTENNARIA DIOICA GAERTN

2019 ◽  
pp. 39-43 ◽  
Author(s):  
LIUDMYLA SLOBODIANIUK ◽  
LILIIA BUDNIAK ◽  
SVITLANA MARCHYSHYN ◽  
ROXOLANA BASARABA
Keyword(s):  
Amino Acids ◽  
Free Amino ◽  
Hplc Method ◽  
Biologically Active Substances ◽  
Biologically Active ◽  
New Drugs ◽  
Raw Material ◽  
Primary Metabolites ◽  
Active Substances

Objective: The purpose of our study was to determine sugars and amino acids content of Antennaria dioica Gaertn. herb. In continuation of the investigation of biologically active substances from Antennaria dioica Gaertn., it advisable to study the qualitative composition and quantitative contents of sugars and amino acids from the herb of this plant. Methods: The herb of Antennaria dioica Gaertn. was analyzed for the content of sugars by GC/MS. The amino acids were identified and quantified by HPLC method. Results: The results of GC/MS analysis showed that in Antennaria dioica Gaertn. herb D-glucose had the highest content (7.16±0.09) mg/g, followed by D-fructose (5.27±0.06) mg/g and D-saccharose (6.72±0.08) mg/g. In the raw material a large amount of monosaccharides derivative–Myo-inositol was revealed, a content of which was (2.12±0.06) mg/g. We determined 17 bound and 16 free amino acids in the Antennaria dioica Gaertn. by HPLC method. Conclusion: The contents of primary metabolites provide opportunities for creating medicine and food supplements. The results show that Antennaria dioica Gaertn. is a rich source of these important biologically active substances. The resulting data will be used with the further purpose to produce new drugs of natural origin.

Sign in / Sign up

Export Citation Format

Share Document