scholarly journals Determination of Caffeine Content in Tea and Maté Tea by using Different Methods

2009 ◽  
Vol 27 (Special Issue 1) ◽  
pp. S213-S216 ◽  
Author(s):  
D. Komes ◽  
D. Horžić ◽  
A. Belščak ◽  
K. Kovačević Ganič ◽  
A. Baljak

Caffeine-containing products have been consumed for hundreds of years for their pleasant flavor and stimulating effects. In recent years, caffeine received increasing attention in food and pharmaceutical industries, due to its pharmacological properties which comprise stimulation of the central nervous system, peripheral vasoconstriction, relaxation of the smooth muscle and myocardial stimulation. The aim of this study was to determine the content of caffeine in five types of tea (white, yellow, green, oolong, black) and two types of maté tea (green maté and roasted maté tea). The content of caffeine was determined by using four different methods: extraction with chloroform, micromethod, method with lead-acetate and high performance liquid chromatography method (HPLC-PDA). The antioxidant capacity of teas as well as of the extracted (“raw”) caffeine was determined by using two methods: reactions with 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) radical (ABTS assay) and Ferric reducing antioxidant power (FRAP assay). The content of caffeine has been associated with plant origin and growth conditions, as well as processing conditions. By applying all four methods, the highest content of caffeine was determined in white tea, whereas maté and roasted maté tea were characterised with the lowest content of caffeine. Spectrophotometric micro-method has proven to be the best alternative to the HPLC method. The highest antioxidant capacity was determined in yellow tea, while the lowest was determined in roasted maté tea. In comparison to the antioxidant capacity of teas, the antioxidant capacity of extracted (“raw”) caffeine is almost negligible, and does not contribute to the overall antioxidant properties of tea.

2017 ◽  
Vol 12 (11) ◽  
pp. 1934578X1701201 ◽  
Author(s):  
Gordana Zdunic ◽  
Dejan Godjevac ◽  
Katarina Savikin ◽  
Silvana Petrovic

A comparative analysis of the phenolic compounds in the 70% EtOH extracts of Hypericum acutum, H. androsaemum, H. barbatum, H. hirsutum, H. maculatum, and H. richeri has been carried out using high-performance liquid chromatography coupled with photodiode array UV detection and high resolution TOF mass spectrometry. Quercetin, astilbin, I3, II8-biapigenin, orientin, 2”- O-acetylorientin, three phenolcarboxylic acids, and eight flavonols 3- O-glycosides were identified in the extracts on the basis of their on-line UV spectra, accurate mass spectral data, and in comparison of retention times with those from the standards. Fingerprint analysis of the extracts revealed significant differences in the qualitative and quantitative chemical composition of the studied species. Antioxidant assays with various reaction mechanisms were used including ferric reducing antioxidant power (FRAP) assay, DPPH, ABTS, superoxide anion radical scavenging capacity and inhibition of liposome peroxidation induced by Fe2+. The most potent were extracts of H. acutum and H. maculatum indicating this Hypericum species interesting for further research aimed as a potentially new source of biologically active compounds.


Antioxidants ◽  
2019 ◽  
Vol 8 (7) ◽  
pp. 234 ◽  
Author(s):  
Petra Šilarová ◽  
Lila Boulekbache-Makhlouf ◽  
Federica Pellati ◽  
Lenka Česlová

Solanum melongena L., also known as eggplant, is a widely consumed vegetable and it is well-known for its beneficial antioxidant properties, due to phenolic compounds. In this work, the influence of different cooking procedures on the content of chlorogenic acid was evaluated on eggplant samples of different geographic origin by high-performance liquid chromatography (HPLC). An easy and quick extraction procedure with 50% methanol as the extraction solvent was optimized for the first time by means of a design-of-experiment and applied to heat treated samples of eggplant. The antioxidant capacity of eggplant extracts was also evaluated by using the ABTS assay and it was correlated with the data obtained by the HPLC method. The content of chlorogenic acid was different in each heat-treated eggplant sample and it depended on the temperature applied during the cooking procedure. In particular, an increase of chlorogenic acid content with rising temperature was observed. Conversely, a very high temperature (250 °C) caused a decrease of chlorogenic acid amount. The influence of storage on the content of chlorogenic acid was also monitored. While the level of chlorogenic acid in fresh samples decreased during four weeks of storage, an increase in its content in heat treated eggplant was observed within the same period. Multivariate data analysis was used to classify eggplant samples into different groups, according to the country of origin and heat treatment procedure. This study provides new insights to preserve the antioxidant properties of eggplant phenolics during different thermal and storage treatments in order to highlight their health promoting effects.


Nutrients ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1723 ◽  
Author(s):  
Jiménez-Moreno ◽  
Cimminelli ◽  
Volpe ◽  
Ansó ◽  
Esparza ◽  
...  

Artichoke waste represents a huge amount of discarded material. This study presents the by-products (bracts, exterior leaves, and stalks) of the “Blanca de Tudela” artichoke variety as a potential source of phenolic compounds with promising antioxidant properties. Artichoke residues were subjected to different extraction processes, and the antioxidant capacity and phenolic composition of the extracts were analyzed by spectrophotometric methods and high performance liquid chromatography (HPLC) analyses, respectively. The most abundant polyphenols in artichoke waste were chlorogenic acid, luteolin-7-O-rutinoside, and luteolin-7-O-glucoside. Minor quantities of cynarin, luteolin, apigenin-7-O-glucoside, apigenin-7-O-rutinoside, and naringenin-7-O-glucoside were also found. The antioxidant activity of the obtained extracts determined by ABTS [2, 2’-azinobis (3-ethylbenzothiazoline-6-sulphonic acid)], DPPH (2,2-diphenyl-1-pycrilhydracyl), and FRAP (Ferric Ion Reducing Antioxidant Power) was highly correlated with the total concentration of phenolic compounds. Chlorogenic acid, luteolin-7-O-glucoside, and luteolin-7-O-rutinoside, the most abundant compounds in 60% methanol extracts, are the components most responsible for the antioxidant activity of the artichoke waste extracts. The extract with the best antioxidant capacity was selected to assay its antioxidant potential on a model intestinal barrier. This action of the hydroxycinnamic acids on intestinal cells (Caco-2) was confirmed. In summary, artichoke waste may be considered a very interesting ingredient for food functionalization and for therapeutic purposes.


2020 ◽  
Vol 11 (2) ◽  
pp. 2543-2548
Author(s):  
Gouru Santhosh Reddy ◽  
Animesh Bera ◽  
Madhurima Basak ◽  
Krishnaveni Nagappan ◽  
Ramalingam Peraman

The present study is aimed to develop a linear, precise, and accurate RP-HPLC (Reverse Phase High-Performance Liquid Chromatography) method for the determination of dapagliflozin in the formulation. The method was accomplished on a C18 column (250×4.6mm; 5µm), & Samples were eluted using acetonitrile: water (40:60%v/v) delivered at a flow rate of 1.0ml/min with a chromatographic run time of 10 min. The eluents were observed utilizing a UV detector with a wavelength set at 277nm. The method that was developed resulted in the retention of dapagliflozin at 7.029minutes. Dapagliflozin through current method has shown linearity (r2 > 0.999) over the concentration range of 1-16 µg/ml. The percentage recovery was observed to be within the limits of 98-102%, demonstrating the accuracy of the method. Limit of detection (LOD) and limit of quantification (LOQ) were qualified at 0.049µg/ml and 0.1485µg/ml, respectively. A Linear, precise, accurate, simple, and rapid RP-HPLC method has been developed and validated for the evaluation of dapagliflozin in bulk drug and tablet dosage forms (5mg &10mg) according to ICH Q2(R1) rules. Additionally, the proposed method could be of use in quality control tests of dapagliflozin in pharmaceutical industries.


2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
Anamaria Hosu ◽  
Claudia Cimpoiu ◽  
Luminita David ◽  
Bianca Moldovan

Cornus species fruits are well known as a rich source of antioxidant compounds responsible for their diverse health benefits. The present study aims to investigate the variation of the total antioxidant capacity of Cornelian cherry (Cornus masL.) fruits during storage, using high-performance thin-layer chromatography (HPTLC) and two spectrophotometric assays based on different mechanisms: the 2,2-azinobis(3-ethylbenzothiazolyne-6-sulphonic acid) radical cation (ABTS+∙) assay and the ferric reducing antioxidant power (FRAP) assay. The fruit extract was stored at room temperature (22°C) for 19 days. No major differences in the total antioxidant capacity were observed during this period, indicating that storage does not have any deleterious effect on the antioxidant properties of the investigated fruits extract. The antioxidant capacity varied between 12.91 and 12.83 µmol Trolox/g fruit as determined by the HPTLC method and from 36.13 to 33.93 µmol Trolox/g fruit as determined by the ABTS assay.


Author(s):  
Soroush Bijani ◽  
Zahra Gharari ◽  
Alireza Ahmadnia ◽  
Hossein Danafar ◽  
Ali Sharafi

Background: Flavonoid-derived components have been studied for their therapeutic properties. Objectives: Apigenin has shown remarkable antioxidant and anti-inflammatory features, so we should have a reliable source of apigenin. Methods: In this study, we used high-performance liquid chromatography method to compare the amount of apigenin in flower, root, leaf, and stem of three varieties of osmos bipinnatus, i.e., ‘Dazzler,’ ‘Xanthos,’ ‘Sensation Pinkie’, and in transgenic root culture of C. bipinnatus ‘Dazzler’. Besides, the antioxidant activity of C. bipinnatus ‘Dazzler’ transgenic root culture was evaluated using Ferric Reducing Antioxidant Power (FRAP) assay. Results: Dazzler variety flowers showed the highest recovery of apigenin with 0.799 mg/100 mg Dry Weight (DW). However, the Sensation pinkie variety leafs had the lowest recovery with 0.089 mg/100mg. Apigenin content in transformed roots (0.797 mg/100 mg DW) of C. bipinnatus ‘Dazzler’ was significantly higher than non-transformed roots (0.42 mg/100 mg DW). The ethanolic extract of hairy root showed the FRAP value of 668.1 µM Fe2+/mg that was comparatively more than the wild root FRAP value (426.2 µM Fe2+/mg). Conclusion: In conclusion, the presence of apigenin in high amounts in hairy root cultures of C. bipinnatus ‘Dazzler’ indicates its great potential for the future pharmaceutical industry.


2020 ◽  
Vol 20 (13) ◽  
pp. 1053-1059
Author(s):  
Mahmoud M. Sebaiy ◽  
Noha I. Ziedan

Background: Allergic diseases are considered as the major burden on public health with increased prevalence globally. Histamine H1-receptor antagonists are the foremost commonly used drugs in the treatment of allergic disorders. The target drug in this study, loratadine, belongs to this class of drugs and its biometabolite desloratadine which is also a non-sedating H1 receptor antagonist with anti-histaminic activity being 2.5 to 4 times greater than loratadine. This study aimed to develop and validate a novel isocratic Reversed-phase High-Performance Liquid Chromatography (RP-HPLC) method for rapid and simultaneous separation and determination of loratadine and its metabolite, desloratadine in human plasma. Methods: The drug extraction method from plasma was based on protein precipitation technique. The separation was carried out on a Thermo Scientific BDS Hypersil C18 column (5μm, 250 x 4.60 mm) in a mobile phase of MeOH: 0.025M KH2PO4 adjusted to pH 3.50 using orthophosphoric acid (85: 15, v/v) at an ambient temperature. The flow rate was maintained at 1 mL/min and maximum absorption was measured using the PDA detector at 248 nm. Results: The retention times of loratadine and desloratadine in plasma samples were recorded to be 4.10 and 5.08 minutes, respectively, indicating a short analysis time. Limits of detection were found to be 1.80 and 1.97 ng/mL for loratadine and desloratadine, respectively, showing a high degree of sensitivity of the method. The method was then validated according to FDA guidelines for the determination of the two analytes in human plasma. Conclusion: The results obtained indicate that the proposed method is rapid, sensitive in the nanogram range, accurate, selective, robust and reproducible compared to other reported methods.


Antioxidants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 234 ◽  
Author(s):  
Yili Hong ◽  
Zening Wang ◽  
Colin J. Barrow ◽  
Frank R. Dunshea ◽  
Hafiz A. R. Suleria

Stone fruits, including peach (Prunus persica L.), nectarine (Prunus nucipersica L.), plum (Prunus domestica L.) and apricot (Prunus armeniaca L.) are common commercial fruits in the market. However, a huge amount of stone fruits waste is produced throughout the food supply chain during picking, handling, processing, packaging, storage, transportation, retailing and final consumption. These stone fruits waste contain high phenolic content which are the main contributors to the antioxidant potential and associated health benefits. The antioxidant results showed that plum waste contained higher concentrations of total phenolic content (TPC) (0.94 ± 0.07 mg gallic acid equivalents (GAE)/g) and total flavonoid content (TFC) (0.34 ± 0.01 mg quercetin equivalents (QE)/g), while apricot waste contained a higher concentration of total tannin content (TTC) (0.19 ± 0.03 mg catechin equivalents (CE)/g) and DPPH activity (1.47 ± 0.12 mg ascorbic acid equivalents (AAE)/g). However, nectarine waste had higher antioxidant capacity in ferric reducing-antioxidant power (FRAP) (0.98 ± 0.02 mg AAE/g) and total antioxidant capacity (TAC) (0.91 ± 0.09 mg AAE/g) assays, while peach waste showed higher antioxidant capacity in 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assay (0.43 ± 0.09 mg AAE/g) as compared to other stone fruits waste. Qualitative and quantitative phenolic analysis of Australian grown stone fruits waste were conducted by liquid chromatography coupled with electrospray-ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS/MS) and HPLC-photodiode array detection (PDA). The LC-ESI-QTOF-MS/MS result indicates that 59 phenolic compounds were tentatively characterized in peach (33 compounds), nectarine (28), plum (38) and apricot (23). The HPLC-PDA indicated that p-hydroxybenzoic acid (18.64 ± 1.30 mg/g) was detected to be the most dominant phenolic acid and quercetin (19.68 ± 1.38 mg/g) was the most significant flavonoid in stone fruits waste. Hence, it could be concluded that stone fruit waste contains various phenolic compounds and have antioxidant potential. The results could support the applications of these stone fruit wastes in other food, feed, nutraceutical and pharmaceutical industries.


2006 ◽  
Vol 89 (6) ◽  
pp. 1552-1556
Author(s):  
ArmaĞan Önal ◽  
Olcay SaĞiri ◽  
S Müge Çetin ◽  
Sidika Toker

Abstract Reboxetine is used as a selective noradrenaline reuptake inhibitor for the treatment of major depressive disorders. It is effective in the treatment of severe depression and safer to use than traditional tricyclic antidepressants. In this study, a novel, simple, and rapid stability-indicating high-performance liquid chromatography (HPLC) method for reboxetine methansulfonate was successfully developed and validated for the assay of tablets. The method was used to quantify reboxetine in tablets; it employed a C18 column (150 4.6 mm id) with an isocratic mobile phase consisting of methanolphosphate buffer (pH 7, 0.02 M; 55 + 45, v/v) at a flow rate of 1.0 μmL/min. Reboxetine was detected by an ultraviolet detector at 277 nm. The retention time of reboxetine was about 4.5 min. The developed HPLC method was validated with respect to linearity, precision, sensitivity, accuracy, and selectivity. The method was linear over the concentration range 150 g/mL (r 0.9999). The limits of detection and the quantitation of reboxetine were 0.1 and 0.3 μg/mL, respectively. The relative standard deviation values for intraday and interday precision were 0.781.01 and 1.081.37%, respectively. Selectivity was validated by subjecting a stock solution of reboxetine to neutral, acid, and alkali hydrolysis, as well as oxidation, dry heat treatment, and photodegradation. The peaks of the degradation products did not interfere with the peak of reboxetine. The results indicated that the proposed method could be used in a stability assay. The proposed method was successfully applied to the determination of reboxetine in tablets. Excipients present in the tablets did not interfere with the analysis.


INDIAN DRUGS ◽  
2016 ◽  
Vol 53 (11) ◽  
pp. 46-50
Author(s):  
Z. G Khan ◽  
◽  
S. S. Patil ◽  
P. K. Deshmukh ◽  
P. O. Patil

Novel, isocratic reversed phase high performance liquid chromatography method was developed and validated for the determination of enzalutamide (EZA) in bulk drug and pharmaceutical formulation. Efficient separation was achieved on PrincetonSPHER C18 100A, 5μ (250×4.6 mm) under the isocratic mode of elution using acetonitrile: water (80:20) % V/V as a mobile phase pumped in to the column at flow rate 1.0 mL/min. The effluent was monitored at 237.0 nm using UV detector. EZA was eluted in the given mobile phase at retention time (tR) of 3.2 minutes. The standard calibration curve was linear over the concentration range 10 - 60 μg/mL with correlation coefficient 0.997. The method was validated for accuracy, precision, sensitivity, robustness, ruggedness and all the resulting data treated statistically. The system suitability parameters like retention time, theoretical plates, tailing factor, capacity factor were found within the limit.


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