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Journal articles on the topic 'Ciocalteu'

Author: Grafiati

Published: 9 March 2023

Last updated: 10 March 2023

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1

Komorowski, James, Devon Bernsley, Sarah Sylla, and Sara Perez Ojalvo. "Enhanced Antioxidant Activity of Phycocyanin Oligopeptides." Current Developments in Nutrition 5, Supplement_2 (June 2021): 336. http://dx.doi.org/10.1093/cdn/nzab037_046.

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Abstract Objectives Phycocyanin, a phytonutrient found in blue-green algae, has various beneficial properties, including potent antioxidant effects. The goal of this study was to investigate the antioxidant potency of a novel phycocyanin oligopeptide (PC-O) compared to phycocyanin (PC). Methods Antioxidant potency of PC-O and PC was measured using two different methods: 1) the Folin-Ciocalteu reaction assay, and 2) the Oxygen Radical Absorbance Capacity (ORAC) 6.0 assay. The Folin-Ciocalteu reaction assay (or total phenolics assay) was run using Folin-Ciocalteu's phenol reagent and sodium carbonate. Optical absorbance was measured at 765nm in a colorimetric plate reader with gallic acid as a reference standard. The ORAC 6.0 assay was run to evaluate the antioxidant capacity of a material against six primary reactive oxygen species: peroxyl radical, hydroxyl radical, superoxide anion, singlet oxygen, peroxynitrite, and hypochlorite. Trolox was used as the reference standard, and the results were expressed as μmole Trolox equivalency per gram of a tested material. Results In both assays, PC-O had higher antioxidant potency than PC. In the Folin-Ciocalteu reaction assay, the cellular antioxidant capacity of PC-O (24 mg/L) was greater than PC (16 mg/L). PC-O also demonstrated consistently higher antioxidant activity in the ORAC 6.0 assay, as follows: peroxyl radicals, PC-O (477 μmole TE/gram) vs. PC (26 μmole TE/gram); hydroxyl radicals, PC-O (734 μmole TE/gram) vs. PC (62 μmole TE/gram); peroxynitrite, PC-O (40 μmole TE/gram) vs. PC (7 μmole TE/gram); super oxide anion, PC-O (172 μmole TE/gram) vs. PC (53 μmole TE/gram); singlet oxygen, PC-O (92 μmole TE/gram) vs. PC (70 μmole TE/gram); and hypochlorite, PC-O (2,805 μmole TE/gram) vs. PC (312 μmole TE/gram). Conclusions These results demonstrate that phycocyanin oligopeptide (PC-O) is a superior antioxidant compared to phycocyanin (PC) as shown by its higher cellular antioxidant capacity in the Folin-Ciocalteu reaction assay and significantly higher ORAC 6.0 scores. Funding Sources This work was supported by Nutrition 21, LLC.

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2

Medina Vargas, Óscar Julio, Luis Carlos Arturo Garzón Salcedo, and Wilfred Edilberto Espinosa Manrique. "Efecto del tiempo sobre la cuantificación de polifenoles totales con el reactivo de Folin-Ciocalteu." I3+ 3, no. 2 (October 2, 2017): 10. http://dx.doi.org/10.24267/23462329.216.

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En este manuscrito se presentan los resultados experimentales obtenidos durante el proceso de cuantificación de polifenoles totales en función del tiempo, mediante la metodología de Folin-Ciocalteu y ácido gálico como molécula de referencia. El trabajo se realizó para obtener el tiempo apropiado de reacción entre el ácido gálicoy el reactivo de Folin-Ciocalteu, dado que en la literatura se encuentra, para esta metodología, un conjunto variado de condiciones que pueden afectar la confiabilidad de los resultados experimentales. Se construyeron 5 curvas de calibración para que el ácido gálico interactuara con el reactivo de Folin-Ciocalteu entre 1,0 y 3,0 horas a intervalos de 30 minutos, y se contrastaron sus valores de pendiente e intercepto entre sí y con los valores de absorbancia del blanco. Se aplicaron las pruebas estadísticas de análisis de varianza de un factor y contraste t para dos medias experimentales. Este estudio permitió demostrar que el tiempo es una variable influyente en la cuantificación de polifenoles totales con el reactivo de Folin-Ciocalteu, y dentro de las condiciones experimentales analizadas se encontró que el tiempo adecuado de interacción fue de 1,0 hora. Palabras clave: ácido gálico, polifenoles totales, reactivo de Folin- Ciocalteu.

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3

Hong, Jung-Il, Hyun-Jung Kim, and Ji-Yun Kim. "Factors Affecting Reactivity of Various Phenolic Compounds with the Folin-Ciocalteu Reagent." Journal of the Korean Society of Food Science and Nutrition 40, no. 2 (February 28, 2011): 205–13. http://dx.doi.org/10.3746/jkfn.2011.40.2.205.

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4

Hapsari, Annisa Mulia, Masfria Masfria, and Aminah Dalimunthe. "Pengujian Kandungan Total Fenol Ekstrak Etanol Tempuyung (Shoncus arvensis L.)." Talenta Conference Series: Tropical Medicine (TM) 1, no. 1 (October 2, 2018): 284–90. http://dx.doi.org/10.32734/tm.v1i1.75.

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Daun tempuyung merupakan salah satu tumbuhan obat tradisional Indonesia yang banyak dimanfaatkan untuk pengobatan batu ginjal, anti inflamasi, disentri, radang dan rematik. Tempuyung banyak mengandung senyawa flavonoid yang merupakan golongan fenol terbesar. Penelitian ini dimulai dengan pengumpulan dan persiapan sampel, skrining fitokimia, pembuatan ekstrak etanol, dan pengujian kandungan total fenol dengan metode kolorimetri pereaksi Folin-Ciocalteu menggunakan spektrofotometer UV-Vis dengan asam galat sebagai baku pembanding. Hasil skrining fitokimia menunjukkan daun tempuyung mengandung senyawa flavonoid. Penetapan kadar total fenol menggunakan metode spektrofotometri pereaksi Folin- Ciocalteu didapat nilai regresi y = 0,00077 x + 0,03667 dengan nilai r2 = 0,99757 sehingga didapat nilai rata – rata kadar total fenol 45,04 ± 0,46 mg GAE/g ekstrak. Tempuyung is one of traditional medical plant in Indonesia and used in kidney stone medication, anti-inflammatory, dysentery, inflammation, and rheumatism. Tempuyung contains substantial flavonoid which considers as the biggest phenol. This research started from the preparation and sample collection, phytochemical screening, ethanol extract preparation, and total phenol test using colorimetry method usingFolin-Ciocalteu reagent byUV-Vis spectrophotometer and gallic acid as the standard compound. The phytochemical screening indicated that tempuyung leaves contained flavonoid compound. The total phenol contentwas determined using colorimetry method of Folin-Ciocalteu reagent and resulted with regression value of y=0.00077 x+0.03667 and the value of r2=0.99757 and the average of total phenolcontent of 45.04 ± 0.46 mg GAE/g.

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5

Way, Madeleine L., Joanna E. Jones, David S. Nichols, Robert G. Dambergs, and Nigel D. Swarts. "A Comparison of Laboratory Analysis Methods for Total Phenolic Content of Cider." Beverages 6, no. 3 (September 7, 2020): 55. http://dx.doi.org/10.3390/beverages6030055.

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Total phenolic content is widely accepted as a key measure of quality for cider. Apple juice and cider, made from six apple varieties including dessert and cider apples, were analysed for total phenolics using three different methods: (a) the Folin-Ciocalteu method, (b) the Somers method (a spectrophotometric method developed specifically for wine), and (c) ultra-performance liquid chromatography (UPLC) as a benchmark test. Of these approaches, the Somers method had the strongest correlation with UPLC with an R2 value of 0.99, whilst the Folin-Ciocalteu correlated with UPLC with an R2 value of 0.89. The Folin-Ciocalteu method also had a strong positive correlation with the Somers approach with an R2 value of 0.91. Correlations between methods were strongest for apple varieties that were naturally high in phenolic content. These results highlight the potential of the Somers method to rapidly, inexpensively, and accurately report the total phenolic content of apple juice and ciders made from dessert and cider apple varieties.

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Park, Kyung A., Yoo-mi Choi, Smee Kang, Mi-Ri Kim, and Jungil Hong. "Effects of Proteins on the Reactivity of Various Phenolic Compounds with the Folin-Ciocalteu Reagent." Korean Journal of Food Science and Technology 47, no. 3 (June 30, 2015): 299–305. http://dx.doi.org/10.9721/kjfst.2015.47.3.299.

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7

Berker, Kadriye Isil, F. Ayca Ozdemir Olgun, Dilek Ozyurt, Birsen Demirata, and Resat Apak. "Modified Folin–Ciocalteu Antioxidant Capacity Assay for Measuring Lipophilic Antioxidants." Journal of Agricultural and Food Chemistry 61, no. 20 (May 13, 2013): 4783–91. http://dx.doi.org/10.1021/jf400249k.

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8

Raza, Asad, and Tariq Mahmood Ansari. "Spectrophotometric Determination of Citalopram in Pharmaceuticals Using Folin-Ciocalteu Reagent." Asian Journal of Chemistry 25, no. 16 (2013): 8913–16. http://dx.doi.org/10.14233/ajchem.2013.14907.

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9

Gil, Dulce Martins de Albuquerque, and Maria Jose Ferreira Rebelo. "Metabisulfite interference in biosensing and Folin-Ciocalteu analysis of polyphenols." Microchimica Acta 167, no. 3-4 (November 10, 2009): 253–58. http://dx.doi.org/10.1007/s00604-009-0249-9.

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10

Nikolaeva, Tat'yana Nikolayevna, Petr Vladimirovich Lapshin, and Natal'ya Viktorovna Zagoskina. "METHOD FOR DETERMINING THE TOTAL CONTENT OF PHENOLIC COMPOUNDS IN PLANT EXTRACTS WITH FOLIN-DENIS REAGENT AND FOLIN-CHOCALTEU REAGENT: MODIFICATION AND COMPARISON." chemistry of plant raw material, no. 2 (June 10, 2021): 291–99. http://dx.doi.org/10.14258/jcprm.2021028250.

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A modification of the method for determining the total content of phenolic compounds in plant tissue extracts with the Folin-Denis reagent and the Folin-Ciocalteu reagent has been carried out, allowing to establish the correspondence of the results obtained when using them. The method using the Folin-Denis reagent is adapted for conducting determinations in microvolumes. For the method using the Folin-Ciocalteu reagent, the concentration of the latter (0.4 N, a 5-fold dilution of the standard reagent) and the composition of the reaction mixture were selected, using which the optical densities of the reduction products of the Folin-Denis and Folin-Ciocalteu reagents containing polyphenols in ethanol extracts from wheat, buckwheat and calus tissue of tea were almost the same. The absorption spectra of the reduction products of these reagents by gallic acid, rutin, (-)-epicatechin, as well as ethanol extracts from wheat, buckwheat, and tea calus tissue, were located in the same region (680–770 nm) and had similar characteristics. Calibration graphs of the dependence of the optical density of solutions on the concentration of standard substances (gallic acid, (-)-epicatechin, rutin), constructed using the Folin-Denis and Folin-Ciocalteu reagents, had a linear character within the concentration range of 10–100 μg/ml and practically coincided. The results of determining the content of phenolic compounds in ethanol extracts of plants, differing in their ability to accumulate, showed very similar and statistically significant values when using these two reagents.

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11

Moanță, Anca, Maria Popa, Cătălina Ionescu, Georgeta Ciobanu, and Mădălina Drăgoi. "Polyphenols with antioxidant activity." Annals of the University of Craiova Series Chemistry 28, no. 1 (September 15, 2022): 40–47. http://dx.doi.org/10.52846/aucchem.2022.1.04.

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12

Webber, Juliana F., and Chase M. Mason. "Utility of the Colorimetric Folin-Ciocalteu and Aluminum Complexation Assays for Quantifying Secondary Metabolite Variation among Wild Sunflowers." Helia 39, no. 65 (December 1, 2016): 157–67. http://dx.doi.org/10.1515/helia-2016-0019.

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AbstractSecondary metabolites serve multiple functions in plants, and play a key role in many ecological processes. Accordingly, the quantification of such compounds is central to addressing many questions in plant science. Alongside precision analytical methods like gas and liquid chromatography-mass spectrometry, there exists a substantial niche for inexpensive and rapid spectrophotometric approaches if their usefulness in a system can be demonstrated. This study seeks to examine the utility of two commonly used colorimetric methods – the Folin-Ciocalteu assay and the aluminum complexation assay – for quantifying variation in leaf phenolic and flavonoid content among members of the genus Helianthus, the sunflowers. Among species known a priori to vary substantially in both the diversity and relative concentrations of secondary metabolites, both assays detect substantial variation among species. Moreover, total phenolic content as assessed by the Folin-Ciocalteu assay correlates positively with concentrations of multiple individual phenolic compounds as quantified by high performance liquid chromatography-mass spectrometry, indicating that the Folin-Ciocalteu describes variation in sunflower phenolic content. Additionally, the diversity of flavonoids known from Helianthus include a number of those known to be sensitive to the aluminum complexation assay, indicating that this assay may also be a useful descriptor of relative variation in sunflower flavonoid content. In total, both the Folin-Ciocalteu and aluminum complexation assays appear to capture useful, if coarse, variation in secondary metabolites among Helianthus species, and seem useful as rapid low-cost methods for exploratory research, preliminary analyses, and potentially useful for high-throughput phenotyping within wild or cultivated sunflower with proper calibration.

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13

Sarker, Umakanta, Md Nazmul Hossain, Shinya Oba, Sezai Ercisli, Romina Alina Marc, and Kirill S. Golokhvast. "Salinity Stress Ameliorates Pigments, Minerals, Polyphenolic Profiles, and Antiradical Capacity in Lalshak." Antioxidants 12, no. 1 (January 11, 2023): 173. http://dx.doi.org/10.3390/antiox12010173.

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Previous studies have shown that salinity eustress enhances the nutritional and bioactive compounds and antiradical capacity (ARC) of vegetables and increases the food values for nourishing human diets. Amaranth is a salinity-resistant, rapidly grown C4 leafy vegetable with diverse variability and usage. It has a high possibility to enhance nutritional and bioactive compounds and ARC by the application of salinity eustress. Hence, the present study aimed to evaluate the effects of sodium chloride stress response in a selected Lalshak (A. gangeticus) genotype on minerals, ascorbic acid (AsA), Folin–Ciocalteu reducing capacity, beta-carotene (BC), total flavonoids (TF), pigments, polyphenolic profiles, and ARC. A high-yield, high-ARC genotype (LS6) was grown under conditions of 0, 25, 50, and 100 mM sodium chloride in four replicates following a block design with complete randomization. We recognized nine copious polyphenolic compounds in this accession for the first time. Minerals, Folin–Ciocalteu reducing capacity, AsA, BC, pigments, polyphenolic profiles, and ARC of Lalshak were augmented progressively in the order: 0 < 25 < 50 < 100 mM sodium chloride. At 50 mM and 100 mM salt concentrations, minerals, AsA, Folin–Ciocalteu reducing capacity, BC, TF, pigments, polyphenolic profiles, and ARC of Lalshak were much greater than those of the control. Lalshak could be used as valuable food for human diets as a potent antioxidant. Sodium chloride-enriched Lalshak provided outstanding quality to the final product in terms of minerals, AsA, Folin–Ciocalteu reducing capacity, BC, TF, pigments, polyphenolic profiles, and ARC. We can cultivate it as a promising alternative crop in salinity-prone areas of the world.

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Lawag, Ivan Lozada, Elisa S. Nolden, Arthur A. M. Schaper, Lee Yong Lim, and Cornelia Locher. "A Modified Folin-Ciocalteu Assay for the Determination of Total Phenolics Content in Honey." Applied Sciences 13, no. 4 (February 7, 2023): 2135. http://dx.doi.org/10.3390/app13042135.

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The Folin-Ciocalteu assay is a widely used method for measuring the total phenolic content (TPC) in honey, but it can be affected by the presence of reducing sugars in honey, which can lead to interference and an over-estimation of its TPC. To optimize the Folin-Ciocalteu assay for honey analysis, the effect of pH on the assay was investigated. A number of pH scenarios were tested using different concentrations of Na2CO3 (0.00%, 0.75%, 0.94%, and 7.50%) in order to minimize reducing sugar interference and maximize the reaction of phenolics in the assay. The modified TPC method was then validated in accordance with current International Council on Harmonisation (ICH) guidelines. The findings of this study demonstrate that the traditional Folin-Ciocalteu assay (using 7.50% aqueous Na2CO3 solution, pH 10.8) leads to a significant overestimation of the TPC of honey due to the interference of reducing sugars. However, a pH of 7.9, achieved by using a 0.75% aqueous Na2CO3 solution, provides suitable conditions to account for most of the phenolic compounds without interference from reducing sugars. This finding was further confirmed by testing various sugar solutions and artificial honey which yielded TPC values below the established limit of detection and quantification of the assay. However, a slight increase in pH, even by a moderate deviation (pH 8.9), leads to significant discrepancies in absorbance readings, indicating that pH control is crucial for the accurate analysis of TPC in honey.

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Carmona-Hernandez, Juan C., Gonzalo Taborda-Ocampo, and Clara H. González-Correa. "Folin-Ciocalteu Reaction Alternatives for Higher Polyphenol Quantitation in Colombian Passion Fruits." International Journal of Food Science 2021 (January 14, 2021): 1–10. http://dx.doi.org/10.1155/2021/8871301.

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Passiflora edulis Flavicarpa, Passiflora edulis Sims, and Passiflora ligularis Juss are Colombian fruits (passion fruits) of important exportation value. They act efficiently as antioxidants, antifungal, and antimicrobial compounds due to their high polyphenol content. Polyphenols can be quantified by the Folin-Ciocalteu (F-C) reaction. Food matrices, solvent polarity, and several different reacting conditions are critical for the optimum extraction and quantification of polyphenols. Chromatographic identification and quantitation are satisfactory with access to a vast number of reference standards considering the availability of abundant phenolic compounds in crude extracts. The purpose of this study was to evaluate alternatives and specific F-C reacting conditions aiming at determining the highest total phenolic content (TPC) in three Colombian Passifloras. Among optimum reacting conditions, reduced reaction time and diluted alkali conditions yielded desirable positive results highlighting lower working time and minimum reagent waste production. For higher extraction yield, acetone 70% was the best solvent to capture more phenolics from the seedless pulp of these Colombian passion fruits.

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Yusnawan, Eriyanto, and Joko S. Utomo. "Mikroanalisis Kandungan Senyawa Fenolik Total Ekstrak Biji Kedelai dengan Reagen Folin-Ciocalteu." Jurnal Penelitian Pertanian Tanaman Pangan 1, no. 1 (April 14, 2017): 73. http://dx.doi.org/10.21082/jpptp.v1n1.2017.p73-81.

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17

Attard, Everaldo. "A rapid microtitre plate Folin-Ciocalteu method for the assessment of polyphenols." Open Life Sciences 8, no. 1 (January 1, 2013): 48–53. http://dx.doi.org/10.2478/s11535-012-0107-3.

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AbstractSeveral methods have been described for the determination of phenolic compounds in animal and plant products using the Folin-Ciocalteu (FC) assay. Most of these methods describe the use of this reagent and sodium carbonate in spectrophotometric methods. The macro FC assay was compared with two micro FC assays carried out on a microplate reader. Excellent correlation was obtained among the three assays with a molar extinction coefficient of 5.228±0.187x103 M−1 cm−1. The micro assay may serve as a high throughput method for the rapid determination of polyphenols in various samples.

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18

Denisenko, T. A., A. B. Vishnikin, and L. P. Tsiganok. "REACTION FEATURES OF 18-MOLIBDODIPHOSPHATE AND FOLIN-CIOCALTEU REAGENT WITH PHENOLIC COMPOUNDS." Аналитика и контроль 19, no. 3 (2015): 242–51. http://dx.doi.org/10.15826/analitika.2015.19.3.001.

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19

Shafique Ahmad, Abdullah, Nafisur Rahman, and Fakhrul Islam. "Spectrophotometric Determination of Ampicillin, Amoxycillin, and Carbenicillin Using Folin-Ciocalteu Phenol Reagent." Journal of Analytical Chemistry 59, no. 2 (February 2004): 119–23. http://dx.doi.org/10.1023/b:janc.0000014736.59554.5c.

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Magalhães, Luís M., Fernando Santos, Marcela A. Segundo, Salette Reis, and José L. F. C. Lima. "Rapid microplate high-throughput methodology for assessment of Folin-Ciocalteu reducing capacity." Talanta 83, no. 2 (December 15, 2010): 441–47. http://dx.doi.org/10.1016/j.talanta.2010.09.042.

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Rover, Marjorie R., and Robert C. Brown. "Quantification of total phenols in bio-oil using the Folin–Ciocalteu method." Journal of Analytical and Applied Pyrolysis 104 (November 2013): 366–71. http://dx.doi.org/10.1016/j.jaap.2013.06.011.

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22

Pailla, Naveen Reddy, and Bhaskar Kuthati. "Spectrophotometric determination of Clinidipine, Efavirenz, Prazosin drugs by using Folin-Ciocalteu Reagent." International Journal of ChemTech Research 13, no. 3 (2020): 210–17. http://dx.doi.org/10.20902/ijctr.2019.130318.

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For the determination of three drugs namely Cilnidipine (CDP), Efavirenz (EVZ), Prazosin (PRZ), a simple, fast, selective and accurate spectrophotometric method has been outlined. This method is based on the development of blue coloured chromogen due to reduction of tungstate and/ or molybdate in Folin-Ciocalteu reagent by Drug in alkaline medium. The coloured species has an absorption maximum at 730 nm, 745 nm and 770 nm and the Beer’s law obeys over the concentration range of 12-72 μg/mL, 10-70 μg/mL, 3-21 μg/mL respectively for the drugs CDP, EVZ, PRZ. This method has been validated according to ICH guidelines and applied to the analysis of pharmaceuticals.

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Roura, Elena, Cristina Andrés-Lacueva, Ramon Estruch, and Rosa M. Lamuela-Raventós. "Total Polyphenol Intake Estimated by a Modified Folin–Ciocalteu Assay of Urine." Clinical Chemistry 52, no. 4 (April 1, 2006): 749–52. http://dx.doi.org/10.1373/clinchem.2005.063628.

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Abstract Background: Plant polyphenols have been studied largely because of the possibility that they might underlie the protective effects afforded by fruit and vegetable intake against cancer and other chronic diseases. Measurement of polyphenol content excreted in urine as an indicator of polyphenol consumption may offer a routine screening method that could be used for these pathologies. Methods: Thirty-six healthy volunteers each received 2 interventions, one with a polyphenol-rich food (cocoa beverage) and one with a polyphenol-free food (milk) as a control, in a randomized cross-over design with 1-week intervals. The total polyphenol content excreted in urine during the 6 h after consumption of the test meals was measured by a modified Folin-Ciocalteu assay after sample cleanup by solid-phase extraction. Results: The mean (SD) concentrations of polyphenols excreted in the urine 6 h after consumption of the test meals differed significantly: 140.95 (49.27) mg catechin/g of creatinine after the polyphenol-rich meal vs 90.43 (46.07) mg catechin/g of creatinine after the control meal (P <0.05). Conclusions: This method allows analysis of a large number of samples per day, which is ideal for use in epidemiologic studies and may enable estimation of polyphenol consumption and determination of their possible role in preventing of certain pathologies, such as cancer, cardiovascular and degenerative diseases.

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Jacangelo, Joseph G., V. P. Olivieri, and Kazuyoshi Kawata. "Thiosulfate-dechlorination interference with the folin-ciocalteu reagent method for protein determination." Water Research 21, no. 9 (September 1987): 1143–44. http://dx.doi.org/10.1016/0043-1354(87)90036-4.

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B, Kulkarni Manasi, and Joshi Anagha M. "AN EXPERIMENTAL DESIGN APPROACH FOR OPTIMIZATION OF MODIFIED COLORIMETRIC FIRST-ORDER DERIVATIVE METHOD FOR ESTIMATION OF SERRALYSIN IN BULK AND PHARMACEUTICAL FORMULATION." Asian Journal of Pharmaceutical and Clinical Research 11, no. 9 (September 7, 2018): 293. http://dx.doi.org/10.22159/ajpcr.2018.v11i9.26999.

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Objective: The aim of the present work is to use experimental design to screen and optimize experimental variables for developing a colorimetric first-order derivative method for determining content of serralysin (SER) using biuret and Folin–Ciocalteu phenol reagent for stable color development. The method is based on the reaction of peptide bond in the protein with Biuret reagent in alkaline medium and further reaction of remaining tryptophan and tyrosine residues with Folin–Ciocalteu Phenol reagent to form a stable blue-colored complex (first-order derivative λmax 620 nm).Materials and Methods: A two-level full factorial design was utilized to screen the effect of Volume of NaOH (A), volume of biuret reagent (B), volume of Folin–Ciocalteu phenol reagent (C), and concentration of NaOH (D) on the formation of blue-colored SER - reagent complex (response - absorbance). A box Behnken experimental design with response surface methodology was then utilized to evaluate the main interaction and quadratic effects of these factors on the selected response.Results: With the help of a response surface plot and contour plot, the optimum values of the selected factors were determined and used for further experiments. These values were volume of NaOH (A) of 1.0 mL, volume of biuret reagent (B) of 0.25 mL, and volume of Folin–Ciocalteu phenol reagent (C) of 10 μL. The proposed method was validated according to the ICH Q2(R1) method validation guidelines. The developed colorimetric first-order derivative method was found to be simple, accurate, rapid, sensitive, precise, and economic. Further optimization of the method with experimental design approach makes it convenient for use in laboratory.Conclusion: The results of present study have clearly shown that an experimental design approach may be effectively applied to the optimization of a modified visible spectrophotometric method for estimation of SER in bulk and in pharmaceutical formulation with the least number of experimental runs possible. The method can be employed successfully for the estimation of SER in both bulk and tablet dosage form.

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Pico, Joana, Remigio Y. Pismag, Mallory Laudouze, and Mario M. Martinez. "Systematic evaluation of the Folin–Ciocalteu and Fast Blue BB reactions during the analysis of total phenolics in legumes, nuts and plant seeds." Food & Function 11, no. 11 (2020): 9868–80. http://dx.doi.org/10.1039/d0fo01857k.

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Solid Phase Extraction (SPE) is highly advised for the analysis of total phenolics in legumes and nuts, even using Fast Blue BB (FBBB), which in turn displayed better performance over SPE-Folin Ciocalteu (FC).

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Ramesh, Pavagada, Kanakapura Basavaiah, and Nagaraju Rajendraprasad. "Sensitive and selective spectrophotometric assay of doxycycline hyclate in pharmaceuticals using Folin-Ciocalteu reagent." Acta Pharmaceutica 60, no. 4 (December 1, 2010): 445–54. http://dx.doi.org/10.2478/v10007-010-0032-9.

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Sensitive and selective spectrophotometric assay of doxycycline hyclate in pharmaceuticals using Folin-Ciocalteu reagentA spectrophotometric method for the determination of doxycycline (DOX) is described. The method is based on the formation of blue colored chromogen due to reduction of tungstate and/or molybdate in Folin-Ciocalteu (F-C) reagent by DOX in alkaline medium. The colored species has an absorption maximum at 770 nm and the system obeys Beer's law over the concentration range 0.75-12.0 μg mL-1DOX. The apparent molar absorptivity is 2.78 × 104L mol-1cm-1. The limit of quantification and detection values are reported to be 0.20 and 0.08 μg mL-1, respectively. Over the linear range applicable, the accuracy and precision of the method were evaluated on intra-day and inter-day basis. The reported mean accuracy value was 101.0 ± 1.7 %, the relative error was ≤ 2.7 % and the relative standard deviation was ≤ 2.5 %. Application of the proposed method to bulk powder and commercial pharmaceutical tablets is also presented. No significant difference was obtained between the results of the proposed method and the official BP method. The procedure described in this paper is simple, rapid, accurate and precise.

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Gurning, Kasta, Sifikal Lumbangaol, Risanti F. R. Situmorang, and Saronom Silaban. "Determination of phenolic contents and antioxidant activity test of ethanol extract of Sirih merah (Piper crocatum Ruiz & Pav.) leaves using the DPPH method." Jurnal Pendidikan Kimia 13, no. 2 (August 1, 2021): 137–42. http://dx.doi.org/10.24114/jpkim.v13i2.26984.

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The research objectives were to identify the secondary metabolite components, total phenolic content and determine the antioxidant activity of the ethanol extract of red betel leaf (Piper crocatum Ruiz & Pav.). The extraction process was carried out by materation using ethanol as a solvent. Determination of total phenolic content was carried out colorimetrically with Folin-Ciocalteu reagent measured at a maximum wavelength of 765 nm. Determination of antioxidant activity using the DPPH method measured by spectrophotometry at a maximum wavelength of 517 nm. The results of phytochemical screening of the ethanolic extract of red betel leaf contain secondary metabolites, including flavonoid, phenolic, tannin, alkaloids, steroids, and triterpenoids. The total phenolic content of the red betel leaf ethanol extract was 0.949±0.003 mg GAE/g d.w. and has antioxidant activity (IC50) 84,656 including strong category as an antioxidant. Keywords: Piper crocatum Ruiz & Pav., Antioxidant, Ethanol extract, Folin-Ciocalteu and DPPH

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Platzer, Melanie, Sandra Kiese, Thomas Herfellner, Ute Schweiggert-Weisz, and Peter Eisner. "How Does the Phenol Structure Influence the Results of the Folin-Ciocalteu Assay?" Antioxidants 10, no. 5 (May 20, 2021): 811. http://dx.doi.org/10.3390/antiox10050811.

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Plants produce a diverse array of secondary metabolites that are generally nonessential but facilitate ecological interactions. Fruits, vegetables, seeds and nuts can accumulate bioactive secondary metabolites with health-promoting properties, including the potent antioxidant activities of phenolic compounds. Several in vitro assays have been developed to measure the polyphenol content and antioxidant activity of plant extracts, e.g., the simple and highly popular Folin-Ciocalteu (FC) assay. However, the literature contains a number of different descriptions of the assay and it is unclear whether the assay measures the polyphenol content or reducing capacity of the sample. To determine the influence of phenolic structures on the outcome of the FC assay, we tested phenols representing different subgroups (phenolic acids, flavonols, flavanols, dihydrochalcones and flavanones). We observed different results for each reference substance and subgroup. Accordingly, we concluded that the FC assay does not measure the polyphenol content of a sample but determines its reducing capacity instead. Assigning the substances to five structural classes showed that the FC results depend on the number of fulfilled Bors criteria. If a molecule fulfills none of the Bors criteria, the FC results depend on the number of OH groups. We did not find a correlation with other single electron transfer assays (e.g., ABTS and DPPH assays). Furthermore, the FC assay was compatible with all five subgroups and should be preferred over the DPPH assay, which is specific for extracts rich in dihydrochalcones or flavanones.

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Singhvi, I., and Anju Goyal. "Visible spectrophotometric estimation of aceclofenac and indapamide from tablets using folin-ciocalteu reagent." Indian Journal of Pharmaceutical Sciences 69, no. 1 (2007): 164. http://dx.doi.org/10.4103/0250-474x.32140.

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Danilewicz, J. C. "Folin-Ciocalteu, FRAP, and DPPH* Assays for Measuring Polyphenol Concentration in White Wine." American Journal of Enology and Viticulture 66, no. 4 (June 19, 2015): 463–71. http://dx.doi.org/10.5344/ajev.2015.15025.

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Hudz, Nataliia, Oksana Yezerska, Mariia Shanajda, Vladimira Horčinová Sedláčková, and Piotr P. Wieczorek. "Application of the Folin-Ciocalteu method to the evaluation of Salvia sclarea extracts." Pharmacia 66, no. 4 (December 31, 2019): 209–15. http://dx.doi.org/10.3897/pharmacia.66.e38976.

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Polyphenols are valuable group of phytoconstituents due to their high antioxidant activity and healing properties. Antioxidant properties of sages are attributed mainly to a high level of phenolic compounds. The aim of the present study was to elaborate an analytical procedure for the evaluation of the content of secondary metabolites of the polyphenol nature in the herb of Clary Sage (Salvia sclarea L.). Four crude extracts of Salvia sclarea herb obtained with different technologies were used to develop an analytical procedure for the total phenolic content (TPC) assay by spectrophotometric method. The optimum conditions for the analysis (time of the reaction, wavelength, and reference substances) were chosen and experimentally justified (60–80 min, 760 nm, gallic acid and rutin, respectively). Under these conditions, the developed analytical procedure is robust in the indicated time and easy for performing in phytochemical or technological laboratories. The yield of TPC from the herb of Salvia sclarea was the highest in the extracts prepared by heating at a temperature of 36–46 °C and with using the ultrasonic bath. TPC was the highest in the extract in which solvent-to-herb ratio was the least (10:1) and particle size was in the range of 2–5 mm. As a result of the studies, the analytical procedure of the determination of TPC was developed and its parameters were justified. This methodology complies with the requirements for pharmaceutical analysis to ensure the reliability of results during pharmaceutical development and routine control of Salvia sclarea extracts.

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Abramovič, Helena, Blaž Grobin, Nataša Poklar Ulrih, and Blaž Cigić. "Relevance and Standardization of In Vitro Antioxidant Assays: ABTS, DPPH, and Folin–Ciocalteu." Journal of Chemistry 2018 (October 29, 2018): 1–9. http://dx.doi.org/10.1155/2018/4608405.

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Trolox, gallic acid, chlorogenic acid, caffeic acid, catechin, epigallocatechin gallate, and ascorbic acid are antioxidants used as standards for reaction with chromogenic radicals, 2,2-diphenyl-1-picrylhydrazyl (DPPH⋅) and 2,2′-azino-bis-3-ethylbenzotiazolin-6-sulfonic acid (ABTS⋅+), and Folin–Ciocalteu (FC) reagent. The number of exchanged electrons has been analyzed as function of method and solvent. A majority of compounds exchange more electrons in FC assay than in ABTS and DPPH assays. In reaction with chromogenic radicals, the largest number of electrons was exchanged in buffer (pH 7.4) and the lowest reactivity was in methanol (DPPH) and water (ABTS). At physiological pH, the number of exchanged electrons of polyphenols exceeded the number of OH groups, pointing to the important contribution of partially oxidized antioxidants, formed in the course of reaction, to the antioxidant potential. For Trolox, small impact on the number of exchanged electrons was observed, confirming that it is more suitable as a standard compound than the other antioxidants.

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Ikawa, Miyoshi, Timothy D. Schaper, Catherine A. Dollard, and John J. Sasner. "Utilization of Folin−Ciocalteu Phenol Reagent for the Detection of Certain Nitrogen Compounds." Journal of Agricultural and Food Chemistry 51, no. 7 (March 2003): 1811–15. http://dx.doi.org/10.1021/jf021099r.

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Magalhães, Luís M., Marcela A. Segundo, Salette Reis, José L. F. C. Lima, and António O. S. S. Rangel. "Automatic Method for the Determination of Folin−Ciocalteu Reducing Capacity in Food Products." Journal of Agricultural and Food Chemistry 54, no. 15 (July 2006): 5241–46. http://dx.doi.org/10.1021/jf060324s.

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Everette, Jace D., Quinton M. Bryant, Ashlee M. Green, Yvonne A. Abbey, Grant W. Wangila, and Richard B. Walker. "Thorough Study of Reactivity of Various Compound Classes toward the Folin−Ciocalteu Reagent." Journal of Agricultural and Food Chemistry 58, no. 14 (July 28, 2010): 8139–44. http://dx.doi.org/10.1021/jf1005935.

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Singh, Dhruv K., and Gunjan Maheshwari. "Spectrophotometric determination of penicillins in pure and pharmaceutical formulations using Folin-Ciocalteu reagent." Drug Testing and Analysis 2, no. 10 (September 23, 2010): 503–6. http://dx.doi.org/10.1002/dta.157.

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Gómez Sierra, Tania, Argelia Sánchez Chinchillas, and Anyhram Navarro Monroy. "Contenido de polifenoles totales y la capacidad antioxidante en alimentos y bebidas." Tequio 5, no. 15 (May 14, 2022): 53–65. http://dx.doi.org/10.53331/teq.v5i15.7284.

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Polyphenols are biologically active compounds with antioxidant properties present in foods such as black tea, coffee, red wine and cocoa; its content depends on atmospheric conditions, cultivation, processing and storage. The objective of this work was to determine the content of polyphenols in foods and beverages by two colorimetric methods and to establish a correlation with the antioxidant capacity. The content of polyphenols was determined by the Folin-Ciocalteu and ISO 9648-1988 methods in foods and beverages and with this, their consumption in the diet could be estimated. The linear correlation between antioxidant capacity and polyphenols (Folin- Ciocalteu method) is from very strong to strong, while with the ISO 9648-1988 method it is from strong to moderate. The foregoing would indicate that by ingesting foods and beverages that have a higher content of polyphenols, they will present a greater antioxidant capacity, favoring the body’s antioxidant defense.

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Aranda Medina, Camila K., Cesar A. Roque Borda, Genesis S. Esquivel Tohalino, Jesús M. Zambrano Salas, and Keny Davi Alvarado Quiroz. "PERFIL COMPARATIVO DE POLIFENOLES TOTALES Y ACTIVIDAD ANTIOXIDANTE DE UNCARIA TOMENTOSA POTENCIADA CON ÁCIDO CÍTRICO." SCIENTIARVM 1, no. 1 (July 4, 2015): 33–37. http://dx.doi.org/10.26696/sci.epg.0148.

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Cat’s claw (Uncaria tomentosa) is a huge liana that grows in the jungles of South America and Mesoamerica. It stands out for containing high concentrations of oxindolic alkaloids and phenolic compounds, especially pro–anthocyanidins. This explains its use in traditional medicine as an anti–inflammatory and antioxidant agent. The present study focused on the latter characteristic. The objective is to enhance it with citric acid, a very common food additive. For this purpose, a gradient of citric acid concentrations was established and the antioxidant profile of aqueous leaf and bark extracts was evaluated with the following assays: Folin–Ciocalteu, DPPH, FRAP and ABTS. Which revealed that the concentration of citric acid and antioxidant capacity are directly proportional variables. The statistical method also confirmed that the difference is significant. On the other hand, citric acid produced better results in peel extracts, although leaf extracts yielded higher values of antioxidant activity. Keywords: Uncaria tomentosa, citric acid, potentiation, antioxidant activity, Folin–Ciocalteu, DPPH, FRAP, ABTS.

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SEIFU, T., B. MEHARI, M. ATLABACHEW, and B. CHANDRAVANSHI. "POLYPHENOLIC CONTENT AND ANTIOXIDANT ACTIVITY OF LEAVES OF URTICA SIMENSIS GROWN IN ETHIOPIA." Latin American Applied Research - An international journal 47, no. 1 (January 31, 2017): 35–40. http://dx.doi.org/10.52292/j.laar.2017.295.

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This study aimed to investigate the antioxidant activity and polyphenolic content of a wild vegetable, Urtica simensi, grown in Ethiopia. Total phenolics, tannin and flavonoid content of leaves extract were determined by the Folin Ciocalteu, Folin Ciocalteu/protein precipitation and aluminum chloride methods, respectively. The antioxidant activity was tested by the DPPH (1,1-diphenyl-2picrylhydrazyl) free radical scavenging method. Results of the determination revealed that total phenols ranged from 15.75 to 22.67 mg gallic acid equivalent/g of dried leaves. Total tannin content ranged between 0.496 to 1.54 mg gallic acid equivalent/g of dried leaves. Similarly, total ﬂavonoids concentration as catechin equivalent varied between 6.89 to 9.03 mg catechin equivalent/g of dried leaves. Leaves of U. simensis were found to have a substantial antioxidant activity ranging between 2.28-2.42 mg ascorbic acid equivalent/g of dried leaves. This study reveals that U. simensis leaves accumulated a substantial amount of polyphenols, particularly flavonoids, and pose a substantial antioxidant activity.

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Faramayuda, Fahrauk, Oktovia El Shara, and Julia Ratnawati. "PENENTUAN KANDUNGAN POLIFENOL TOTAL EKSTRAK METANOL KULIT BUAH RAMBUTAN RAPIAH (Nephelium lappaceum L.)." Medical Sains : Jurnal Ilmiah Kefarmasian 7, no. 1 (March 24, 2022): 57–66. http://dx.doi.org/10.37874/ms.v7i1.262.

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Tanaman rambutan rapiah (Nephelium lappaceum L.) merupakan tanaman yang tersebar luas di Indonesia. Konsumsi buah rambutan rapiah dapat meninggalkan limbah kulitnya yang cukup banyak. Kulit buah rambutan rapiah telah digunakan secara tradisional sebagai obat demam dan disentri. Kulit buah rambutan rapiah diketahui mengandung metabolit sekunder seperti polifenol, flavonoid, saponin, dan tanin. Penelitian sebelumnya melaporkan bahwa ekstrak metanol kulit buah rambutan memiliki aktivitas antioksidan yang kuat. Metabolit sekunder yang diduga memiliki aktivitas antioksidan adalah polifenol. Penelitian lebih lanjut perlu dilakukan, mengingat potensi kulit buah rambutan rapiah sebagai antioksidan kuat. Tujuan penelitian ini adalah untuk mengetahui kadar polifenol total ekstrak metanol kulit buah rambutan rapiah (Nephelium lappaceum L.). Penetapan kadar polifenol total dilakukan dengan menggunakan metode Folin Ciocalteu. Pereaksi Folin Ciocalteu akan bereaksi dengan gugus fenolik-hidroksil dan membentuk kompleks fosfotungstat-fosfomolibdat berwarna biru yang dapat dideteksi dengan spektrofotometer UV-Vis pada panjang gelombang 743,5 nm. Dari penelitian ini kadar polifenol total yang diperoleh adalah 0,2482±0,0401%.

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Rotty, Marsella, Max R. J. Runtuwenen, and Vanda S. Kamu. "Aktivitas Penghambatan Oksidasi Asam Linoleat Ekstrak Metanol Daun Soyogik (Saurauia bracteosa DC) dengan Metode Ferric Thiocyanate." Jurnal MIPA 6, no. 2 (October 25, 2017): 42. http://dx.doi.org/10.35799/jm.6.2.2017.17756.

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Telah dilakukan penelitian untuk menentukan kandungan total fenolik dan aktivitas antioksidan ekstrak metanol daun soyogik (Saurauia bracteosa DC) sebagai peredam radikal bebas asam linoleat. Kandungan total fenolik diukur dengan metode Folin-Ciocalteu sedangkan aktivitas antioksidan diukur dengan metode FTC (Ferric Thiocyanate) untuk mengetahui kemampuan penghambatan peroksida pada tahap pertama oksidasi lipid. Hasil penelitian menunjukkan bahwa ekstrak metanol memiliki kandungan total fenolik sebesar 99,67 mg/kg dan kemampuan dalam menghambat oksidasi asam linoleat sebesar 49,464%.This research has been conducted to measure the total phenolic compounds and the antioxidant activity of methanol extract of soyogik leaves (Saurauia bracteosa DC) as a reducer of free radicals linoleic acid. The total phenolic content was measured using folin-ciocalteu method, meanwhile the antioxidant activity was measured using FTC (Ferric Thiocyanate) method and to determine the peroxide inhibitory capability in the first stages of lipid peroxidation. The results showed that the methanol extract had a total phenolic content of 99, 67 mg/kg and peroxide inhibition of 49, 464%

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Lerebulan, Chivon, Fety Fatimah, and Julius Pontoh. "Rendemen Dan Total Fenolik Santan Kelapa Dalam Pada Berbagai Tingkat Kematangan." Jurnal MIPA 7, no. 1 (April 22, 2018): 44. http://dx.doi.org/10.35799/jm.7.1.2018.19283.

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Telah dilakukan penelitian untuk menentukan rendemen santan dan total fenolik santan kelapa dalam pada berbagai tingkat kematangan. Santan kelapa dibuat dengan cara kelapa dikupas, dibuang kulit coklat yang menempel pada daging kelapa, selanjutnya daging kelapa diparut, ditimbang, diperas, dan disaring. Penentuan kandungan total fenol menggunakan metode Folin-Ciocalteu. Dari hasil pengujian menunjukkan rendemen santan kelapa dalam tua merupakan nilai yang paling tertinggi sebesar 28.57 g/mL dan total nilai fenolik yang tertinggi terdapat pada santan kelapa dalam tua sebesar 143.9 mg/kg.Research has been conducted to determine coconut content and total phenolic from coconut milk in various level of maturity. Coconut milk made by coconut peeled, discarded brown skin attached to coconut meat, then coconut meat grated, weighed, squeezed, and filtered. Determination of total phenol content using Folin-Ciocalteu method. The results showed that coconut milk content in the oldest was the highest value of 28.57 g / mL and the highest total phenolic value was found in coconut milk in old age of 143.9 mg / kg.

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Michiu, Delia, Maria-Ioana Socaciu, Melinda Fogarasi, Anamaria Mirela Jimborean, Floricuţa Ranga, Vlad Mureşan, and Cristina Anamaria Semeniuc. "Implementation of an Analytical Method for Spectrophotometric Evaluation of Total Phenolic Content in Essential Oils." Molecules 27, no. 4 (February 16, 2022): 1345. http://dx.doi.org/10.3390/molecules27041345.

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Over the past decade, there has been growing interest in polyphenols’ research since these compounds, as antioxidants, have several health benefits, such as preventing neurodegenerative diseases, inflammation, cancer, cardiovascular diseases, and type 2 diabetes. This study implements an analytical method to assess the total phenolic content (TPC) in essential oils using Folin–Ciocalteu’s phenol reagent and quantifies the individual phenolic compounds by liquid chromatography. Thus, the research design and methodology included: (1) extraction of essential oil from dried thyme leaves by hydrodistillation; (2) spectrophotometric measurement of TPC by Folin–Ciocalteu method; and (3) identification and quantification of individual phenolic compounds by high-performance liquid chromatography-diode array detection/electrospray ionization mass spectrometry (HPLC-DAD-ESI-MS). Results revealed a TPC of 22.62 ± 0.482 mg GAE/100 µL and a polyphenolic profile characterized by phenolic acids (52.1%), flavonoids (16.1%), and other polyphenols (31.8%). Thymol, salvianolic acid A, and rosmarinic acid were the major compounds of thyme essential oil. The proposed analytical procedure has an acceptable level of repeatability, reproducibility, linearity, LOD (limit of detection), and LOQ (limit of quantification).

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Lee, Eun Jin, Noa Nomura, Bhimanagouda S. Patil, and Kil Sun Yoo. "Measurement of total phenolic content in wine using an automatic Folin-Ciocalteu assay method." International Journal of Food Science & Technology 49, no. 11 (April 30, 2014): 2364–72. http://dx.doi.org/10.1111/ijfs.12557.

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Yoo, Kil Sun, Eun Jin Lee, Daniel Leskovar, and Bhimanagouda S. Patil. "Development of an Automated Method for Folin-Ciocalteu Total Phenolic Assay in Artichoke Extracts." Journal of Food Science 77, no. 12 (November 19, 2012): C1279—C1284. http://dx.doi.org/10.1111/j.1750-3841.2012.02973.x.

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Harju, Anni M., and Martti Venäläinen. "Measuring the decay resistance of Scots pine heartwood indirectly by the Folin-Ciocalteu assay." Canadian Journal of Forest Research 36, no. 7 (July 1, 2006): 1797–804. http://dx.doi.org/10.1139/x06-074.

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To exploit the variation in the natural durability of heartwood timber, screening of a large number of trees or timber is necessary. We suggest that the concentration of total phenolics, measured by the Folin–Ciocalteu (FC) assay, can be used to supplement or even replace in vitro decay tests for screening the variation in the resistance of Scots pine (Pinus sylvestris L.) heartwood timber against the brown-rot fungus Coniophora puteana (Schum. ex Fr.). We screened the juvenile heartwood of 520 Scots pine trees with the FC assay. Samples from 40 trees, with total phenolics concentrations ranging from 1.9 to 21.7 mg tannic acid equivalents (TAE)/g of heartwood, were subjected to an in vitro decay test. The correlation (r) between the total phenolics concentration and mass loss was –0.82 (p < 0.001) in the 7 week long decay test. The relationship was expressed with a linear regression equation: mass loss (mg/g) = 487 – 25 × concentration of total phenolics (mg TAE/g). This strong relationship could be exploited by replacing the decay test with the FC assay to more rapidly assess the durability of wood products.

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Sánchez-Rangel, Juan Carlos, Jorge Benavides, J. Basilio Heredia, Luis Cisneros-Zevallos, and Daniel A. Jacobo-Velázquez. "The Folin–Ciocalteu assay revisited: improvement of its specificity for total phenolic content determination." Analytical Methods 5, no. 21 (2013): 5990. http://dx.doi.org/10.1039/c3ay41125g.

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Sastry, C. S. P., and A. Rama Mohana Rao. "Application of Folin-Ciocalteu reagent for the spectrophotometric determination of some nonsteroidal antiinflammatory agents." Journal of Pharmacological Methods 19, no. 2 (April 1988): 117–25. http://dx.doi.org/10.1016/0160-5402(88)90032-0.

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Gasic, Uros, Dalibor Stankovic, Dragana Dabic, Dusanka Milojkovic-Opsenica, Maja Natic, Zivoslav Tesic, and Jelena Mutic. "Analytical possibilities for the relative estimation of the antioxidative capacity of honey varieties harvested in different regions of Serbia." Journal of the Serbian Chemical Society 81, no. 5 (2016): 567–74. http://dx.doi.org/10.2298/jsc150313009g.

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Two different approaches, spectroscopic and electrochemical, were applied for rough determination of antioxidative potential of honey samples. Honey samples of diverse botanical origin were collected in different geographical regions in Serbia. Total phenolic content (TPC) was determined by Folin-Ciocalteu method. Cyclic voltammograms on a glassy carbon electrode in KCl supporting electrolyte were used to check electrode sensitivity to the presence of honey. In order to calculate Trolox Equivalent Antioxidant Capacity (TEAC) of studied honey, cyclic voltammograms were recorded for Trolox standard. The results were expressed as ?mol of Trolox Equivalents per kg of sample (?mol TE kg-1). Good correlations were observed between cyclic voltammetry data and total phenolic content (TPC) determined by Folin-Ciocalteu method and radical scavenging activity (RSA) determined using DPPH?(1,1-diphenyl-2-picrylhydrazyl radical) test. Cyclic voltammetry appears to be a highly attractive alternative method for rapid estimation of antioxidative potential of honeys. It was found that polyfloral honey samples had the highest, whereas acacia honey showed the lowest values of TPC.

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