Quantification Of Gallic Acid Research Articles

Determination and Quantification of Gallic Acid in Raw Propolis by High-performance Liquid Chromatography–Diode Array Detector in Burundi

Background: Honey, pollen, and propolis are among the products that bees process and derive from plants and flowers. Propolis is a resinous material that bees gather from the buds and bark of some trees and small plants. Propolis from temperate climates mainly contains phenolic compounds, in contrast with propolis from tropical climates, which mainly contains terpenes. This study aimed to determine, characterise, and quantify the phenolic content of raw propolis from Burundi. Methods: In this study, a total of 6 samples were collected from the provinces of Rumonge, Cibitoke, and Ruyigi in Burundi. Fifteen phenolic compounds (caffeic acid, ferulic acid, epigallocatechin gallate, isoferulic acid, cinnamic acid, caffeic acid phenethyl ester, gallic acid, apigenin, chrysin, galangin, quercetin, kaempherol, rutin trihydrate, naringenin, and pinocembrin) were used as high-performance liquid chromatography (HPLC) standards for qualitative and quantitative analyses of the propolis samples. Results: Among the 15 phenolic compounds checked, only 1 – gallic acid – was detected at a measurable level using an HPLC-diode array detector system. Conclusion: In addition to terpenes, propolis found in sub-Saharan Africa may contain phenolic compounds. Further advanced investigation of sub-Saharan African propolis is required for more detailed characterisation.

Determination and Quantification of Gallic Acid in Raw Propolis by High-performance Liquid Chromatography–Diode Array Detector in Burundi

Background: Honey, pollen, and propolis are among the products that bees process and derive from plants and flowers. Propolis is a resinous material that bees gather from the buds and bark of some trees and small plants. Propolis from temperate climates mainly contains phenolic compounds, in contrast with propolis from tropical climates, which mainly contains terpenes. This study aimed to determine, characterise, and quantify the phenolic content of raw propolis from Burundi. Methods: In this study, a total of 6 samples were collected from the provinces of Rumonge, Cibitoke, and Ruyigi in Burundi. Fifteen phenolic compounds (caffeic acid, ferulic acid, epigallocatechin gallate, isoferulic acid, cinnamic acid, caffeic acid phenethyl ester, gallic acid, apigenin, chrysin, galangin, quercetin, kaempherol, rutin trihydrate, naringenin, and pinocembrin) were used as high-performance liquid chromatography (HPLC) standards for qualitative and quantitative analyses of the propolis samples. Results: Among the 15 phenolic compounds checked, only 1 – gallic acid – was detected at a measurable level using an HPLC-diode array detector system. Conclusion: In addition to terpenes, propolis found in sub-Saharan Africa may contain phenolic compounds. Further advanced investigation of sub-Saharan African propolis is required for more detailed characterisation.

Determination and Quantification of Gallic Acid in Raw Propolis by High-performance Liquid Chromatography–Diode Array Detector in Burundi

Background: Honey, pollen, and propolis are among the products that bees process and derive from plants and flowers. Propolis is a resinous material that bees gather from the buds and bark of some trees and small plants. Propolis from temperate climates mainly contains phenolic compounds, in contrast with propolis from tropical climates, which mainly contains terpenes. This study aimed to determine, characterise, and quantify the phenolic content of raw propolis from Burundi. Methods: In this study, a total of 6 samples were collected from the provinces of Rumonge, Cibitoke, and Ruyigi in Burundi. Fifteen phenolic compounds (caffeic acid, ferulic acid, epigallocatechin gallate, isoferulic acid, cinnamic acid, caffeic acid phenethyl ester, gallic acid, apigenin, chrysin, galangin, quercetin, kaempherol, rutin trihydrate, naringenin, and pinocembrin) were used as high-performance liquid chromatography (HPLC) standards for qualitative and quantitative analyses of the propolis samples. Results: Among the 15 phenolic compounds checked, only 1 – gallic acid – was detected at a measurable level using an HPLC-diode array detector system. Conclusion: In addition to terpenes, propolis found in sub-Saharan Africa may contain phenolic compounds. Further advanced investigation of sub-Saharan African propolis is required for more detailed characterisation.

Comparative Pharmacokinetics of Gallic Acid After Oral Administration of Gallic Acid Monohydrate in Normal and Isoproterenol-Induced Myocardial Infarcted Rats.

Gallic acid (GA) is a polyphenolic natural product widely distributed in food, beverage, and traditional Chinese herbs with beneficial effects on the cardiovascular system. In this research, a comparative study was conducted to investigate the possible difference of pharmacokinetic process in normal and isoproterenol-induced myocardial infarcted rats after oral administration of GA monohydrate with the dose of 50 and 100 mg/kg, respectively. Quantification of GA in rat plasma was achieved by using a simple and rapid high-performance liquid chromatographic method. The results revealed that pharmacokinetics of GA were greatly different between normal and pathological state. GA exhibited slower absorption into the bloodstream, and yielded 1.7-fold (50 mg/kg GA) and 1.3-fold (100 mg/kg GA) less values of area under concentration–time curve as well as 2.5-fold lower of maximum blood concentration (Cmax) in MI rats than those in normal rats. In addition, significant prolonged T1/2 and MRT as well as decreased CL were also registered in MI rats. Our findings suggest that myocardial infarction could alter the pharmacokinetic process of GA, and thus the potential pharmacokinetic differences of herbal preparations (or dietary nutrition) containing GA between normal and pathological conditions should be brought to the forefront seriously in clinical practice.

DETERMINATION OF ANTIOXIDANT CAPACITY AND GALLIC ACID CONTENT IN ETHANOLIC EXTRACT OF PUNICA GRANATUM L. LEAF

Objective: The present research work was carried out to evaluate the antioxidant potential of ethanolic extract of Punica granatum leaf (EPGL) that belongs to the family of Punicaceae and determine its gallic acid (GA) content using chromatography method.Methods: Six complementary test systems, namely, 1,1-diphenyl 2-picryl hydrazine (DPPH), hydrogen peroxide (H2O2), superoxide (SO), nitric oxide (NO), hydroxyl (OH) radical scavenging, and reducing power activities were analyzed for determining antioxidant activity of EPGL. The simple and novel chromatography techniques such as thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) were used for the detection and quantification of GA in EPGL.Results: IC50 values of EPGL were found to be 136 μg/ml for DPPH, 88.5 μg/ml for H2O2, 16.8 μg/ml for SO, 96.5 μg/ml for NO, and 143 μg/ml for OH. The ascorbic acid (AA) and GA were used as standard compounds. The absorbance of EPGL in reducing power assay was found to be 0.18 at 100 μg/ ml, while AA and GA absorbance was found to be 0.24 and 0.4 at the same concentration. The amount of GA in EPGL was found to be 1.189 mg/g.Conclusion: These findings suggested that EPGL could be a potential source of natural antioxidant, and HPLC method used for the determination of GA is simple, precise, accurate, and suitable for routine analysis of GA in EPGL.

Determination of Gallic Acid in Ayurvedic Polyherbal Formulation Triphala churna and its ingredients by HPLC and HPTLC

Triphala churna is well known Ayurvedic formulation in official Ayurvedic Formulary of India, It is used for immune system stimulation, improvement of digestion, relief of constipation, gastrointestinal tract cleansing, relief of gas, treatment of diabetes, eye disease, anaemia, jaundice, asthma, fever, chronic ulcers etc. Standardization of herbal formulation is essential in order to assess the quality, purity, safety and efficacy of the drug. In this, study attempts to evaluate the qualitative estimation of bio active compounds Gallic acid and Ellagic acid by HPTLC and quantification of Gallic acid by HPTLC and HPLC Chromatographic methods. The method employed in current study resulted in good peak shape of Gallic acid. The Rf value of Ellagic acid 0.47 and Gallic acid is 0.56 in all the samples and reference standard was found comparable under UV light at 254 nm and 366 nm. The percentage of free Gallic acid is prominent in Emblica officinalis and lower in Terminalia chebula of Triphala churna ingredients.

High-performance Liquid Chromatographic Method for the Quantification of Gallic Acid in Simhanada Guggulu

Marker compounds quantification with new analytical tools and methods is necessary for establishing the authenticity and usage of Ayurvedic or herbal formulations. Simhanada guggulu or guggul is one of the supportive Ayurvedic medicines for treatment of rheumatoid arthritis and used in various disorders in Ayurveda such as limping, anemia, gout, disease of skin, cough, abdominal lump, pain digestive impairment. Simhanada guggulu is an Ayurvedic herbal formulation made by some selected herbs. The rejuvenating and tonic properties of ‘Simhanada guggulu’ are considered majorly due to their antioxidant principles, which in turn is due to the presence of phenolic compounds. A high-performance liquid chromatography (HPLC) method has been developed for quantitative determination of the gallic acid in ‘Simhanada guggulu’. The acidic mobile phase used in RP18 column which enabled efficient separation of gallic acid. A binary gradient with mobile phase containing solvent A (Acetonitrile) and solvent B (water: 0.3% O-Phosphoric Acid) was used for analysis. Elution was carried out at flow rate of 0.8 mL/min. Pure gallic acid Rt was found to be 5.29 min and peak with same Rt was also observed in prepared formulation. Gallic acid content of prepared formulation was found to be 2.28 %. The developed HPLC-UV method is simple, rapid and help as tool for the standardization of Simhanda guggulu.

Chromatographic profiling of Pancharishta at different stages of its development using HPTLC, HPLC, GC–MS and UPLC–MS

Pancharishta is the traditional Ayurvedic polyherbal formulation prepared by decoction of plant materials followed by fermentation for preservation and facilitation of extraction due to the production of alcohol. Since the preparation of pancharishta involves various steps. The aim of the current investigation was to carry out comparative metabolomics profiling at different stages of preparation for the understanding impact of different steps and ingredients. A decoction of 21 plant materials are main components in pancharishta formulations followed by fermentation and addition of other ingredients with or without fermentation yielded eight different formulations. The vacuum concentration of pancharishta samples yielded a semisolid mass of different formulations ranging from 8 to 37% w/v. The HPTLC fingerprinting analysis of samples was carried out in butanol: ethanol: 0.5% v/v ammonia (5:4:0.5, v/v/v). Derivatization with anisaldehyde-sulphuric acid showed the presence of two major peaks at Rf 0.29 and 0.35. The peak at Rf 0.29 is intense in a formulation containing 12 extra plant materials. Quantification of gallic acid, ellagic acid, tannic acid, kaemferol and quercetin were carried out on newly developed HPLC method using acetonitrile and 0.5% v/v formic acid with a gradient elution. A significant difference in their content was found in different formulations. Further, polar and nonpolar metabolites of pancharishtha were analyzed using UPLC–MS and GC–MS, respectively. GC–MS profiling results in the identification of 144 metabolites among them 26 are common metabolites at different stages. The UPLC–MS analysis resulted in the tentative identification of 43 metabolites. The results of UPLC–MS and GC–MS analysis were used for multivariate analysis using XLSTAT. Principal Component Analysis plot distributed all samples into four different clusters with two formulations each.

HPLC Standardization of The Methanolic Extract of Acrocarpus fraxinifolius leaves based on Gallic acid Content

High-Performance Liquid Chromatography (HPLC) was developed for the standardization and quantification of gallic acid in the methanolic extract of Acrocarpus fraxinifolius Weight & Arn leaves. Linearity was observed in the range of 0.4–2 mg/mL with a correlation coefficient (r2) of 0.9978. The limit of detection (LOD) and limit of quantification (LOQ) were 0.0054 mg/mL and 0.0163 mg/mL, respectively indicating the sensitivity of the applied method. Recovery values of 100.377 % indicate the best accuracy of the method. Gallic acid content was quantified as 168.75 ± 1.05 mg/g methanolic extract. This developed method was simple, accurate and precise to be used as a reference standard method for determination of gallic acid content in the plant extract.

Antioxidant and Nephroprotective Activities of the Extract and Fractions of Homonoia riparia Lour.

Background:Homonoia riparia is a plant, which is widely used in the indigenous system of medicine for the treatment of urolithiasis, renal disorders and inflammatory conditions. This is the first report on the antioxidant and nephroprotective activities of whole plant of H. riparia.Objective:The present study aims at investigating the in vitro antioxidant and nephroprotective activity of the methanol extract and its different fractions of H. riparia.Methods:Petroleum ether (HRPE), Ethyl acetate (HREA), Butanol (HRBU), aqueous fractions (HRAQ) were prepared from the crude methanol extract of H. riparia (HRM) using liquid partitioning. Total phenolic content, flavonoid content and antioxidant activity assay were performed according to suitable methods. Nephroprotective activities were evaluated by MTT assay using Human Embryonic Kidney cells against cisplatin induced toxicity. Quantification of gallic acid was performed using validated HPTLC method.Results:The studies showed that extract and fractions possess significant nephroprotective activity against cisplatin induced renal toxicity. All the extracts/fractions of whole plant of Homonoia riparia was found to be significantly reducing cisplatin induced toxicity (< 0.05). The highest activity was observed with HRBU and HRAQ with a percentage viability of 293.09 ± 4.3 and 345.07 ± 3.2 at a concentration of 200 µg/ml. Gallic acid was detected in the HRM/fractions using HPTLC.SUMMARY Cisplatin (8 μg/ml) exhibited 50 % inhibition in cell viability in HEK 293 cellsButanol and aqueous fractions of Homonoia riparia showed significant nephroprotective activity against cisplatin induced cell damage in HEK cells.Gallic acid was detected and quantified in the extract and fractions of whole plant of Homonoia riparia Abbreviations used: HPTLC: High Performance Thin Layer Chromatography, DPPH: 1,1-diphenyl-2-picrylhydrazyl, ABTS: 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, MTT: 3-(4,5-dimethylthiazolyl-2-yl)-2,5- diphenyl tetrazolium bromide, GAE: Gallic acid equivalents, QE: Quercetin equivalents, HEK: Human Embryonic Kidney, HRM: Methanol extract of H. riparia, HRPE: Petroleum ether fraction of H. riparia, HREA: ethyl acetate fraction of H. riparia, HRBU: Butanol fraction of H. riparia, HRAQ: Aqueous fraction of H. riparia, DMEM: Dulbecco's minimum essential medium, FBS: Foetal bovine serum, DMSO: Dimethyl sulfoxide, ANOVA: One way analysis of variance.

Resolving Identification Issues of Saraca asoca from Its Adulterant and Commercial Samples Using Phytochemical Markers.

Saraca asoca (Roxb.) De Wilde (Ashoka) is a highly valued endangered medicinal tree species from Western Ghats of India. Besides treating cardiac and circulatory problems, S. asoca provides immense relief in gynecological disorders. Higher price and demand, in contrast to the smaller population size of the plant, have motivated adulteration with other plants such as Polyalthia longifolia (Sonnerat) Thwaites. The fundamental concerns in quality control of S. asoca arise due to its part of medicinal value (Bark) and the chemical composition. Phytochemical fingerprinting with proper selection of analytical markers is a promising method in addressing quality control issues. In the present study, high-performance liquid chromatography of phenolic compounds (gallic acid, catechin, and epicatechin) coupled to multivariate analysis was used. Five samples each of S. asoca, P. longifolia from two localities alongside five commercial market samples showed evidence of adulteration. Subsequently, multivariate hierarchical cluster analysis and principal component analysis was established to discriminate the adulterants of S. asoca. The proposed method ascertains identification of S. asoca from its putative adulterant P. longifolia and commercial market samples. The data generated may also serve as baseline data to form a quality standard for pharmacopoeias.SUMMARY Simultaneous quantification of gallic acid, catechin, epicatechin from Saraca asoca by high-performance liquid chromatographyDetection of S. asoca from adulterant and commercial samplesUse of analytical method along with a statistical tool for addressing quality issues. Abbreviations used: HPLC: High Performance Liquid Chromatography; RP-HPLC: Reverse Phase High Performance Liquid Chromatography; CAT: Catechin; EPI: Epicatechin; GA: Gallic acid; PCA: Principal Component Analysis.

The Tissue Distribution and Urinary Excretion Study of Gallic Acid and Protocatechuic Acid after Oral Administration of Polygonum Capitatum Extract in Rats.

In the present study, we investigated the tissue distribution and urinary excretion of gallic acid (GA) and protocatechuic acid (PCA) after rat oral administration of aqueous extract of Polygonum capitatum (P. capitatum, named Herba Polygoni Capitati in China). An UHPLC-MS/MS analytical method was developed and adopted for quantification of GA and PCA in different tissue homogenate and urine samples. Interestingly, we found that GA and PCA showed a relatively targeted distribution in kidney tissue after dosing 60 mg/kg P. capitatum extract (equivalent to 12 mg/kg of GA and 0.9 mg/kg of PCA). The concentrations of GA and PCA in the kidney tissue reached 1218.62 ng/g and 43.98 ng/g, respectively, at one hour after oral administration. The results helped explain the empirical use of P. capitatum for kidney diseases in folk medicine. Further studies on urinary excretion of P. capitatum extract indicated that GA and PCA followed a concentrated elimination over a 4-h period. The predominant metabolites were putatively identified to be 4-methylgallic acid (4-OMeGA) and 4-methylprotocatechuic acid (4-OMePCA) by analyzing their precursor ions and characteristic fragment ions using tandem mass spectrometry. However, the amount of unchanged GA and PCA that survived the metabolism were about 14.60% and 15.72% of the total intake, respectively, which is reported for the first time in this study.

Quantification of Pharmacologically Active Marker Gallic Acid and Ellagic Acid from Leaf and Stem of Pergularia daemia Forsk. by HPTLC Method

TLC densitometry method for quantification of gallic acid and ellagic acid using HPTLC is developed. This is the first report of quantification of these two biologically active compounds as gallic acid and ellagic acid using HPTLC from this plant. Quantification of gallic acid and ellagic acid was carried out from the methanol extract by using solvent system of Toluene: Ethyl acetate: Formic acid (6:4:0.8 v/v/v). The Rf value of Gallic acid and ellagic acid are 0.43 and 0.38 respectively. The linearity ranges of gallic acid (100 to 600 ng) and ellagic acid (100 to 600 ng) with correlation coefficient (r- values) of 0.9994 and 0.9997 respectively. The amount of gallic acid and ellagic acid was 3.01 and 11.09 μg/ml in leaf and 4.97 and 18.30 μg/ml in stem respectively. Quantification of gallic acid and ellagic acid showed good separation and resolution from other constituent of extract. Its main advantages are its simplicity, accuracy and selectivity. This method can also be used for estimation of these compounds in other herbal preparation and may be useful for standardization purposes.

Reversed-phase-liquid chromatography method for separation and quantification of gallic acid from hydroalcoholic extracts of Qualea grandiflora and Qualea parviflora.

Background:Qualea parviflora and Qualea grandiflora (Vochysiaceae), commonly known in Brazil as “pau-terra” and “pau-terrinha,” respectively, have been widely used in the treatment of ulcer and gastritis. These therapeutic effects are attributed to various compounds present in the plants, including phenolic compounds such as gallic acid, due to their important antioxidant activity.Objective:The aim of the present study was to validate a high performance liquid chromatography with diode array detection (HPLC-DAD) method for the quantitative determination of gallic acid in the stem bark of Q. parviflora and Q. grandiflora hydroalcoholic extracts.Materials and Methods:The chromatography analysis was successfully achieved on a Dionex column, Acclaim® 120 (250 mm × 4.60 mm, 5 µm) with a gradient elution of water and methanol at a flow rate of 0.8 mL/min and ultraviolet detection at 280 nm.Results:The validation data, including linearity, precision, specificity, accuracy and robustness of this method demonstrated good reliability and sensitivity.Conclusion:The method is able to quantify gallic acid in the stem bark of both species. What is more, the chromatographic peaks showed good resolution and there are also the advantages of easy sample preparation and a short time between each injection.

An UHPLC–MS/MS method for simultaneous quantification of gallic acid and protocatechuic acid in rat plasma after oral administration of Polygonum capitatum extract and its application to pharmacokinetics

Ethnopharmacological relevancePolygonum capitatum Buch.-Ham. ex D. Don has been traditionally used by Hmong for the treatments of urinary tract infections and pyelonephritis. Gallic acid (GA) and protocatechuic acid (PCA) are regarded as two of the main bioactive compounds in the herb. Materials and methodsA rapid, selective and sensitive UHPLC–ESI–MS/MS method was established and validated for the quantification of GA and PCA in rat plasma after oral administration of P. capitatum extract. Concentrations of GA and PCA were determined at different time points after dosing 20mg/kg (equivalent to 4mg/kg of GA and 0.3mg/kg of PCA), 60mg/kg and 120mg/kg of P. capitatum extract. The main pharmacokinetic parameters of GA and PCA were obtained based on the analysis of the plasma sample by non-compartmental analysis. ResultsAfter oral administration of P. capit]atum extract, GA and PCA were quickly absorbed and showed a dose-dependent profile. Pharmacokinetic parameters for GA and PCA following oral administration of the extract were respectively: Cmax 246.24–806.27 and 15.73–30.72ng/mL; Tmax 40–100 and 20–40min. In the rats treated with P. capitatum t1/2 and Tmax of GA were prolonged by comparing with that of its pure form. ConclusionOther compounds in P. capitatum extract may be metabolized to GA, which affected the pharmacokinetic profiles of GA. This pharmacokinetic study seems to be useful for a further clinical study of P. capitatum extract.

Pharmacognostical and high performance thin layer chromatography studies on leaves of Clerodendrum infortunatum L.

Background:Clerodendrum infortunatum L. commonly known as Bhant plays a significant role in Indian System of Medicine, that is, Ayurveda, due to its medicinal properties. It grows easily in waste places of all areas of India, Bangladesh, and Myanmar.Aim:The present study was carried out with a view to lay down its pharmacognostic standards along with high-performance thin layer chromatography (HPTLC) studies in order to document/validate its therapeutic benefits.Materials and Methods:In this research, leaves of C. infortunatum were subjected to pharmacognostic evaluation parameters such as macroscopy, quantitative microscopy, physicochemical studies, phytochemical screening. HPTLC has been developed for detection and quantification of gallic acid and tyrosine in C. infortunatum. Increasing serial dilutions of reference standard gallic acid (20–100 μg/mL) and tyrosine (20–100 μg/mL) were scanned at 254 nm and 280 nm, respectively.Results:Microscopy of leaf revealed the presence of anisocytic stomata, sclereids, glandular and covering trichome, and prisms of calcium oxalate crystal. The total ash, water-soluble, and acid insoluble ash values of leaves were 9.95%, 2.15%, and 0.70%, respectively. The maximum extractive value of crude powder was in the water. HPTLC studies revealed that the amount of gallic acid in the crude powder of test sample were high (0.244 mg/g) in comparison to tyrosine (0.081 mg/g).Conclusion:The data generated would be of significant use for the authentication of drug and would also serve as a reference for the standardization and quality control of C. infortunatum.

Quantification of gallic acid in fruit and leaves of Careya arborea by High performance thin layer chromatography (HPTLC)

Objective: The present study was aimed to quantification of Gallic acid in Careya arborea (Lecythidaceae). Method: High performance thin layer chromatography (HPTLC) quantification was carried out for various extract of leaf and fruits of C. arborea. The thin layer chromatography (TLC) plate was spotted with gallic acid and fruits and leaves extract of Careya arborea. The extract of fruit and leaves shows the Gallic acid spot at Rf: value 0.68 using mobile phase ethyl acetate: toluene: formic acid (8:2:0.3, v/v). So, the gallic acid was selected as marker. The gallic acid was quantified using HPTLC technique in CFE (C. arborea fruit ethyl acetate extract), CFA (C. arborea fruit alcoholic extract), CLE (C. arborea leave ethyl acetate extract) and CLA (C. arborea alcoholic extract of leaves) of Careya arborea. Result: The percentage (w/w) amount of gallic acid was found to 2.11%, 1.2 %, 0.54% and 0.48% in CFE, CFA, CLE and CLA of C. arborea respectively. Conclusion: This HPTLC quantification method useful for standardization of fruits and leaf Careya arborea.

Simultaneous detection of green tea catechins and gallic acid in human serum after ingestion of green tea tablets using ion-pair high-performance liquid chromatography with electrochemical detection

We developed an analytical method for the simultaneous determination of tea catechins and gallic acid (GA) in human serum using ion-pair high-performance liquid chromatography (HPLC) with electrochemical detection. GA was measured to estimate the amount of gallate moiety produced by degradation of gallated catechins ((-)-epicatechin-3-gallate, ECG; (-)-epigallocatechin-3-gallate, EGCG). Ethyl gallate was adopted as an internal standard to correct for the extraction efficiency. To maximize extraction efficiency, a hydrophobic polytetrafluoroethylene (PTFE) filter was selected for pre-treatment prior to separation. HPLC separation was performed using a C18 reversed-phase column with a gradient mobile phase of phosphate buffer (pH 2.5) containing tetrahexylammonium hydrogensulfate as an ion-pair reagent. Using this method, (-)-epicatechin (EC), (-)-epigallocatechin (EGC), ECG, EGCG, ethyl gallate, and GA were detected as single peaks. The resolution values for target analytes were 4.0-13.0 and the mean values of the absolute recoveries of catechins and GA were 77.3-93.9%. The detection limits for catechins and GA in serum were 0.4-3.1ng/mL. The serum catechin levels of eight healthy volunteers after ingestion of a single dose of green tea tablets were measured using this method. The concentration of total catechins (free+conjugated forms) in serum peaked 60min after ingestion. From these results, this method is thought to enable the simultaneous quantification of GA, the hydrolysis product of gallated catechins, and target catechins, and to be sufficiently sensitive for pharmacokinetic studies of catechins following oral administration of green tea.

High-performance thin-layer chromatographic analysis of antioxidants present in different parts of Saraca asoca (Roxb.) de Wilde

ObjectiveGallic acid, ellagic acid and quercetin are the important antioxidant compounds of Saraca asoca (Roxb.) de Wilde (Caesalpiniaceae). This report describes the determination of free radical scavenging activity in different plant parts (of S. asoca) by DPPH assay with correlation, and quantification of gallic acid, ellagic acid and quercetin in different plant parts by a simple, sensitive and validated HPTLC method. MethodologyMethanolic extracts of bark, leaf and flowers of S. asoca were investigated for their antioxidant potential with the aid of DPPH assay followed by HPTLC analysis for quantitative evaluation of antioxidants (gallic acid, ellagic acid, and quercetin) in different plant parts. ResultsHPTLC analysis exhibited high amount of gallic acid and quercetin in flower (0.320% and 0.11% w/w respectively) and high amount of ellagic acid in bark (0.4805% w/w) which corresponds to low IC50 values of 6.83 ± 0.07 μg/ml and 6.6 ± 0.10 μg/ml respectively, indicating the remarkable antioxidant activity of these two plant parts whereas moderate amount of gallic acid (0.164 %w/w) and very low amount of quercetin (0.0445% w/w) and ellagic acid (0.04% w/w) correlate high IC50 value of 28.6 ± 0.62 μg/ml representing its poor antioxidant potential. ConclusionConsumption of bark and flower of S. asoca could be beneficial by virtue of its high antioxidant activity. The flower and bark may be considered as a source of gallic acid and ellagic acid respectively. The presence of moderate amount of gallic acid in leaf can be an alternative source.

Quantification of Pharmacologically Active Markers Gallic Acid, Quercetin and Lupeol from Acacia Leucophloea Wild Flowers by HPTLC Method

Objective: TLC densitometric method for quantification of gallic acid, quercetin and lupeol using HPTLC is developed. This is the first report of quantification of these three bioactive compounds viz. Gallic acid, quercetin and lupeol using HPTLC from this plant. Methodology: Quantification of gallic acid and quercetin was carried out from the methanolic extract using the solvent system of Toluene:Ethyl acetate:Formic acid (6:4:0.8 v/v/v). Lupeol was quantified from chloroform extract using the solvent system of Toluene:Ethyl acetate (7:3 v/v). Results: The Rf values of gallic acid, quercetin and lupeol are 0.22, 0.37 and 0.70 respectively. The linearity ranges for gallic acid (100 to 600 ng), quercetin (2000 to 7000 ng) and lupeol (100 to 1200 ng) with correlation coefficients (r-values) of 0.99968, 0.99708, and 0.99971 respectively. The amount of gallic acid, quercetin and lupeol was 124.31, 580.4, 24.89 μg/ml respectively. Conclusion: Quantification of gallic acid, quercetin and lupeol showed good resolution and separation from other constituents of extract. Its main advantages are its simplicity, accuracy, and selectivity. This method can also be used for the estimation of these compounds in other herbal preparations and may be useful for standardization purposes.