Determination Of Polyphenolic Compounds Research Articles

Determination of polyphenolic compounds in raw plant materials by NMR spectroscopy

Environmental monitoring and assessment of the prospects for extracting biologically active substances (BAS) from various types of plant biomass requires the development of simple and fast methods for measuring their content in raw materials. For this purposes massspectrometry and NMR spectroscopy are widely used. Both methods have their own advantages and disadvantages. But NMR spectroscopy is a nondestructive method and requires simple sample preparation. In addition, quantitative studies using NMR spectroscopy do not require authentic standard samples. We have developed various techniques for targeted metabolomic analysis of plant origin samples using NMR spectroscopy, including: determination of anthraquinone derivatives in extracts from roots and rhizomes of Rubia tinctorum L., determination of diosmin in Hyssopus officinalis L., determination glucofrangulin A in extracts from leaves of Rhamnus frangula L.

Development оf the Recipe Composition of a Functional Snack Bar Based on Vegetable Ingredients

Advances in the development of modern snack bar formulations demonstrate the wide variety of ingredients used and their combinations. At the same time, the prevailing trends in the food market orient manufacturers towards the active use of ingredients of plant origin. Analysis of literary sources made it possible to substantiate the choice of recipe ingredients for creating a functional snack bar: processed products of raspberries and blueberries, apples, dates, cashews, soy protein isolate. The use of a new combination of known ingredients requires solving a number of problems that make a key contribution to the creation of product technology and the development of its formulation. The aim of the study was to experimentally substantiate and develop a recipe for a ready-to-eat functional snack bar based on herbal ingredients. The work used raw materials that meet the requirements of GOST, TU, and generally accepted methods of analysis: determination of polyphenolic compounds, flavones, flavonols was carried out by spectrophotometric method; organic acids and vitamin C - by titrimetric method; nutritional value of snack bar samples by protein, fat, carbohydrates and dietary fiber content - by calculation method. As a result of the research carried out, the recipe for the snack bar was experimentally substantiated and developed, taking into account the new composition of the selected herbal ingredients; technological solutions for its implementation are proposed. It has been shown that berry ingredients used in work (concentrated raspberry and blueberry juices, freeze-dried blueberry powder and freeze-dried raspberries) are a source of natural components useful for human health - organic acids, polyphenolic compounds, including flavones and flavonols, as well as vitamin C. The combination of berry ingredients with other recipe components - date paste, apple syrup, apple fibers, soy protein isolate, cashew nuts - results in a finished product with acceptable taste and consumer properties and an increased content of protein and functional food ingredients - vitamin C and dietary fiber. It was found that the consumption of one serving (50 g) of a snack bar obtained according to the proposed recipe allows satisfying the physiological need of an adult in protein by 5.7-10.8%, fats - 1.1-2.5%, digestible carbohydrates - 5.4 -12.6%, dietary fiber - 14.4 -18.0%, vitamin C - 11.2%, covering an adequate level of consumption of flavones and flavonols - by 45.5%. The snack bar obtained according to the developed recipe contains only natural sugars and can be positioned as a product that is a source of protein, vitamin C and a product with a high dietary fiber content. The results of the research carried out can be recommended for use in production to expand the assortment line of healthy snacks. For the development of a complete package of technological solutions, directions for further research are outlined, which will be aimed at finding and justifying effective packaging solutions that ensure the quality, safety of the product and the safety of biologically active substances during storage

Development of harmonized HPTLC methods for determination of polyphenolic compounds of tinctures

The tincture is a traditional liquid dosage form for the pharmaceutical market of Ukraine. Today, the range of the tinctures of Ukrainian manufacturers has 21 different items, while only six monographs on different tinctures are included in the State Pharmacopoeia of Ukraine. For standardization of tinctures, different combinations of specific and non-specific physical and chemical methods are used. The high-performance thin-layer chromatography (HPTLC) is a modern and specific chromatographic method, that can be used for the identification of polyphenolic substances responsible for a wide range of pharmacological activities of the tinctures.
 The purpose of the study was to identify and compare chromatographic fingerprints (images of chromatograms and peak profiles from images) of flavonoids and phenylpropanoids of 10 tinctures of Ukrainian production in the harmonized mobile phases, to select for each tincture the specific marker zones, to determine the suitability of the specified chromatographic conditions for standardization of the tincture and the possibility to perform in these conditions the quality control for several different tinctures in-parallel.
 The objects of the investigation were Hawthorn tincture, Peppermint tincture, Sage tincture, Motherwort tincture, Calendula tincture, Sophora tincture, Echinacea purpurea tincture, Valerian tincture, Peony tincture, Eucalyptus tincture. The research was carried out using the HPTLC method in the HPTLC automatic herbal system (CAMAG, Switzerland) on the base of two laboratories.
 For each investigated tincture, the determination and comparison of HPTLC chromatographic fingerprints (images and peak profiles of images) of flavonoids and phenylpropanoids obtained in different harmonized mobile phases were performed.
 In the harmonized chromatographic conditions the difference in separation of the bioactive substances was determined; the characteristic marker substances of the tinctures were identified; the suitability of the mobile phase for individual analysis of the tincture or in-parallel analysis of different tinctures on the same plate were determined; the possibility to replace one mobile phase by another, if needed, was determined.
 Proposed HPTLC methods were developed using modern procedure and approach. These allow to reduce of the scope and time of analysis, optimize the economical and labor costs. The findings are of special importance for the pharmaceutical manufacturers and quality control laboratories that perform analysis on a large scale.

Ecofriendly microwave-assisted reaction and extraction of bioactive compounds from hawthorn leaf.

The main active components in hawthorn leaves possess various biological activities such as anti-inflammatory, antioxidant, and hypolipidemic effects. Therefore, it is necessary to develop an effective and reliable extraction method to extract these active compounds from hawthorn leaves. To establish a simple, rapid, and sensitive method for extraction and determination of polyphenolic compounds from hawthorn leaves. In this study, a microwave-assisted reaction and extraction (MARE) combined with ultra-high-performance liquid chromatography with ultraviolet detector method was established to extract and determine the polyphenolic compounds in hawthorn leaves. The solid reagent aqueous solutions were applied as extraction solvents, preventing the use of organic solvents. The target analytes were identified by quadrupole time-of-flight tandem mass spectrometry. Several experimental parameters that can significantly affect the extraction efficiency were evaluated and optimised. The optimal conditions were as follows: 0.1g of sodium carbonate was used as solid reagent, the amount of sodium borate was set at 0.01g, extraction time was 10min, extraction temperature was set at 50°C, pH value was adjusted to 7. The validation experiments demonstrated that the method had high sensitivity with the limits of detection in the range 26.5-37.7ng/mL. The average recoveries ranged from 80.22% to 93.27%. In this work, the proposed MARE method was successfully applied to extract and determine polyphenolic compounds in hawthorn leaf samples. Compared with other reported methods, the present method was faster, greener, and more sensitive.

The study on development of the liquid extract with the broncholytic action

Aim. To determine the extractant and the multiplicity of extraction when developing the technology of the extract by the method of percolation. Materials and methods. To determine the optimal extraction conditions the extract was obtained using the method of percolation. Each extract was selected fractionally in DER step 1 : 1 (the drug extract ratio is the ratio of the initial material to the extract obtained). For each sample the quantitative determination was performed, and the main indicators of the process dynamics were calculated. The extraction process was carried out to obtain the total extract of DER 1 : 10. For each sample of the extract the dry residue and the basic physical and chemical characteristics were determined. The extraction process was controlled by the quantitative determination of polyphenolic compounds by spectrophotometric method of analysis. Results. The maximum yield of the amount of phenolic compounds calculated with reference to gallic acid was observed when extracting the raw material with alcohol in the concentration of 70 %. When determining the extraction multiplicity of the raw material in the composition of the complex liquid extract based on the analysis of the dry residue and the content of polyphenolic compounds calculated with reference to gallic acid it was determined that the optimal extraction multiplicity in obtaining the liquid extract was 3. Conclusions. Based on the studies conducted on determination of extractives in the medicinal plant raw material an effective extractant – 70 % ethyl alcohol has been identified. After analyzing the extracts of the medicinal plant raw material per the amount of extractives, dry residue and polyphenolic compounds the effective multiplicity of extraction of the total liquid extract with the broncholytic activity has been determined to be 3.

Determination of Polyphenolic Compounds by Ultra-Performance Liquid Chromatography Coupled to Tandem Mass Spectrometry and Antioxidant Capacity of Spanish Subtropical Fruits

In an analysis of the seven types of subtropical fruits most consumed and produced in southern Spain, UPLC-ESI-MS/MS was used to quantify 14 phenolic species: five hydroxycinnamic acids, seven hydroxybenzoic acids and two flavonoids (quercetin and naringenin). In each case, in addition, antioxidant capacity was determined by FRAP, ABTS and DPPH. Of these fruits, carambola (or starfruit) presented the highest levels of phenolic compounds, cherimoya (custard apple) and kiwi were the richest in non-flavonoid phenolic compounds and papaya had the highest levels of the flavonoids studied. Higher mean values were recorded in home-grown fruits than in imported varieties by ABTS and DPPH methods. Persimmon’s antioxidant capacity was well above that of the other fruits, according to our analyses.

Determination of polyphenolic compounds in Cirsium palustre (L.) extracts by high performance liquid chromatography with chemiluminescence detection

The first method for the simultaneous determination of polyphenolic antioxidants in extracts from leaves of Cirsium palustre based on high performance liquid chromatography combined with flow injection chemiluminescence detection (HPLC-FI-CL) has been developed. The extracts were prepared by using methanol as extraction medium and two types of extraction methods (reflux and ultrasound assisted extraction). The post-column CL determination of polyphenols was based on their enhancing effect on the chemiluminescence intensity generated in manganese(IV)–hexametaphosphate–formaldehyde system in a phosphoric acid medium. Main antioxidants determined in C. palustre leaves were eriodictyol-7-O-glucoside, luteolin-7-O-glucoside and 6-hydroxyluteolin-7-O-glucoside belonging to flavonoids, and chlorogenic acid belonging to phenolic acids. Chromatographic separation was carried out on a C18 column with gradient elution by using a mobile phase containing 0.25% (v/v) phosphoric acid in water (solvent A) and 100% methanol (solvent B). Under the optimized conditions of chromatographic separation and CL detection the validation of the method was performed. The calibration curves showed good linearity in the concentration range from 0.5 to 40µgmL−1. The HPLC-FI-CL method was successfully applied to the determination of four polyphenolic compounds in methanolic extracts from leaves of C. palustre. The accuracy of the developed method was confirmed by the comparison of the results with those obtained by an HPLC-PDA method. The relative error of determination does not exceed 6.1%. However, the HPLC-FI-CL method is characterized by 40–65 times higher sensitivity compared to the HPLC-PDA method.

Study of the Effect of Surfactants on Extraction and Determination of Polyphenolic Compounds and Antioxidant Capacity of Fruits Extracts

Micelle/water mixed solutions of different surface active agents were studied for their effectiveness in the extraction of polyphenolic compounds from various varieties of apples from west Azerbaijan province in Iran. The total content of polyphenolic compound in fruit extracts were determined using ferrous tartrate and Folin–Ciocalteu assays methods and chromatographic methods and compared with theme. High performance liquid chromatography is one of the most common and important methods in biochemical compound identification. The effect of pH, ionic strength, surfactant type, surfactant concentration, extraction time and common organic solvent in the apple polyphenolics extractions was studied using HPLC-DAD. Mixtures of surfactants, water and methanol at various ratios were examined and micellar-water solutions of Brij surfactant showed the highest polyphenol extraction efficiency. Optimum conditions for the extraction of polyphenolic compounds from apple occurred at 7 mM Brij35, pH 3. Effect of ionic strength on extraction was determined and 2% (W/V) potassium Chloride was determined to be the optimum salt concentration. The procedure worked well with an ultrasound bath. Total antioxidant capacity also was determined in this study. The method can be safely scaled up for pharmaceutical applications.

Determination of polyphenolic compounds by liquid chromatography–mass spectrometry in Thymus species

Polyphenolic compounds represent a wide group of phytochemicals, including well-known subgroups of phenolic acids, flavonoids, natural dyes, lignans etc., which are produced by plants. These natural bioactive compounds possess a variety of beneficial effects including antioxidant and anticarcinogenic activities, protection against coronary diseases as well as antimicrobial properties. Thymus species have already been reported as sources of different phenolic acids and flavonoids. Moreover, the composition and content of flavonoids in Thymus species play important role as taxonomic markers providing distinction of species. High-performance liquid chromatography (HPLC) coupled with diode array detector (DAD) and on-line mass spectrometry (ESI-MS) method was used for analysis. The method was evaluated for a number of validation characteristics (repeatability and intermediate precision, LOD, LOQ, calibration range, and recovery). The polyphenolic pattern of five native Hungarian Thymus species ( T. glabrescens Willd., T. pannonicus All., T. praecox Opiz, T. pulegioides L., and T. serpyllum L.) was characterized. The dominant compound was rosmarinic acid, which ranged between 83.49 μg g −1 and 1.436 mg g −1. Other phenolic acids (ferulic acid, caffeic acid and its other derivatives, chlorogenic acid and p-coumaric acids) were present in every examined Thymus species, as well as flavanones: naringenin, eriodictyol and dihydroquercetin; flavones: apigenin and apigenin-7-glucoside, flavonols: quercetin and rutin. The polyphenolic pattern was found to be a useful additional chemotaxonomic tool for classification purposes and determination of the locality of origin.

Determination of polyphenolic compounds in commercial herbal drugs and spices from Lamiaceae: thyme, wild thyme and sweet marjoram by chromatographic techniques

HPLC and HPTLC methods were used for a qualitative and quantitative determination of luteolin-7-O-β-glucuronide, lithospermic acid, rosmarinic acid and mthyl rosmarinate, together with other known compounds, in commercial herbal drugs and spices from lamiaceous species: Thymi herba, Serpylli herba and Majoranae herba. The contents of analyzed compounds in the studied hydrophilic extracts, prepared form herbal sources, were established using a C18 column with acetonitrile–water–formic acid as a mobile phase. The HPLC method was validated for linearity, precision and accuracy. Luteolin-7-O-β-glucuronide and lithospermic acid were identified as new wild thyme constituents, luteolin-7-O-β-glucuronide and methyl rosmarinate as new compounds in sweet marjoram. Methyl rosmarinate was isolated for the first time from thyme. The investigated herbal drugs and spices provide polyphenols in high amounts, even up to 84.3mg per 1g of a dried herb.

Determination of polyphenolic compounds in wastewater olive oil by gas chromatography–mass spectrometry

A simple and sensitive method for the determination of 21 polyphenolic compounds in wastewater from olive oil production plants is proposed. The method involves a liquid–liquid microextraction (LLME) procedure with ethyl acetate followed by a silylation step. Identification and quantification have been performed by gas chromatography–mass spectrometry (GC–MS). MS measurements were carried out using selected ion monitoring mode (SIM). α-Naftol was used as internal standard. The proposed method was applied to the determination of these compounds in wastewater from an olive oil production factory in Jaén (Spain) at concentration levels ranging from 1.0 to 75.0 μg ml −1 for each compound. The autodegradation process by own microbiota in samples collected in three different points of the factory was also studied. The method was validated by a recovery assay with spiked samples.

Determination of polyphenolic compounds in grape seed extracts using reverse-phase high performance liquid chromatography

Oxidative stress is associated with many kinds of chronic diseases. Antioxidants such as polyphenols are compounds that protect cells against the damaging effects of reactive oxygen species. Grape seeds are considered good resources of polyphenols, and grape seed extracts have a very strong antioxidant effect. In the present study, we established a simple gradient reverse-phase high performance liquid chromatography method to determine polyphenol content from three different grape seed resources. An ODS (2), <TEX>$150\;{\times}\;3.2\;mm$</TEX> column has been employed, and six polyphenols have been determined: gallic acid, protochatechuic acid, (+)-catechin, (-)-epicatechin, procyanidin B2, and epicatechin gallate. Catechin and epicatechin were the main polyphenol compounds in all three extracts. The amount of procyanidin B2 was higher in Extract 1 (from a company of China), while Extract 2 (extracted in our lab) and Extract 3 (from a company of USA) contained higher proportions of epicatechin gallate. For the total polyphenol content, Extract 1 was much higher than that of Extract 2 and 3. The results suggest that the dietary dose of grape seed extracts from different resources should be adjusted according to polyphenol content.

Determination of polyphenolic compounds in leaf protein concentrates of lucerne and their effect on the nutritional value

Leaf protein concentrates were prepared by heat coagulation of lucerne ‘brown juice’. A fraction of the phenolics was completely extractable by organic solvents. Coumestrol (which occurs in lucerne leaf proteins) was estimated after progressive elution with solvents and fluorimetry in solution. Significant reductions of both coumestrol content and total flavonoides were observed after washing of the concentrates.