Determination of Tannins in White Wines by Thermal Lens Spectrometry

Claderaforteza, A.; Tomasmas, C.; Estelaripoll, J.M.; Cerdà-Martín, Víctor; Ramis‐Ramos, Guillermo

doi:10.1006/mchj.1995.1063

Cited by 7 publications

(5 citation statements)

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“…The detection limit was 9× 10 -9 mol/L (signal-to-noise ratio=3). This is about one order of magnitude lower in detection limit and more than one order of magnitude wider in dynamic range than those obtained by conventional spectrometry [14], HPLC [15], and an electrochemical method [17].…”

Section: Working Curves and Detection Limitsmentioning

confidence: 99%

“…It has been found to be pharmacologically active as an antioxidant, antimutagenic, and anticarcinogenic agent [10,11,12,13]. In past years, various methods have been applied to determine GA, such as spectrometry [14], chromatography [15], capillary electrophoresis [16], electrochemical analysis [17], and the oscillating chemical reaction detection method [18]. The flow injection analysis of pyrogallol and GA with enhanced electrochemiluminescent detection based on the luminol system has also been studied previously in our group [19,20].…”

Section: Introductionmentioning

confidence: 99%

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Flow injection analysis of gallic acid with inhibited electrochemiluminescence detection

Lin

Yongqiang

et al. 2004

Analytical and Bioanalytical Chemistry

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A flow injection (FI)-electrochemiluminescent (ECL) method has been developed for the determination of gallic acid, based on an inhibition effect on the Ru(bpy)(3)(2+)/tri- n-propylamine (TPrA) ECL system in pH 8.0 phosphate buffer solution. The method is simple and convenient with a determination limit of 9.0x10(-9) mol/L and a dynamic concentration range of 2x10(-8)-2x10(-5) mol/L. The relative standard deviation (RSD) was 1.0% for 1.0x10(-6) mol/L gallic acid ( n=11). It was successfully applied to the determination of gallic acid in Chinese proprietary medicine-Jianming Yanhou Pian. The inhibition mechanism proposed for the quenching effect of the gallic acid on the Ru(bpy)(3)(2+)/TPrA ECL system was the interaction of electrogenerated Ru(bpy)(3)(2+*) and o-benzoquinone derivative at the electrode surface. The ECL emission spectra and UV-visible absorption spectra were applied to confirm the mechanism.

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Section: Working Curves and Detection Limitsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Flow injection analysis of gallic acid with inhibited electrochemiluminescence detection

Lin

Yongqiang

et al. 2004

Analytical and Bioanalytical Chemistry

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“…It is known that the DPPH reagent has a high affinity toward lipophilic antioxidants but not as much for hydrophilic ones. ,, The FC chromophore, the molybdotungstophosphate heteropolyanion (PMoW 11 O 40 4– ), does not have an affinity toward organic solvents owing to its quadruple negative charge giving rise to strong ion–dipole interactions with solvent water molecules. Therefore, once formed, the anion cannot be easily extracted into organic solvents, though extraction using quaternary ammonium-type (i.e., methyltrialkyl (C 8 –C 10 ) ammonium chloride) cationic surfactant from aqueous carbonate solution into chloroform was tried with limited success, as very low absorbances had to be magnified with thermal lens spectrometry . Thus, the conventional FC assay is mainly carried out in aqueous phase and is inapplicable in its current form to lipophilic antioxidants .…”

Section: Introductionmentioning

confidence: 99%

“…Therefore, once formed, the anion cannot be easily extracted into organic solvents, though extraction using quaternary ammonium-type (i.e., methyltrialkyl (C 8 −C 10 ) ammonium chloride) cationic surfactant from aqueous carbonate solution into chloroform was tried with limited success, as very low absorbances had to be magnified with thermal lens spectrometry. 23 Thus, the conventional FC assay is mainly carried out in aqueous phase and is inapplicable in its current form to lipophilic antioxidants. 4 In a most widely cited review work of Huang et al, 4 the authors stated that they have actually "attempted but have been unable to measure the total phenols of the lipid soluble fraction of bee pollen as the sample did not have sufficient water solubility".…”

Section: ■ Introductionmentioning

confidence: 99%

Modified Folin–Ciocalteu Antioxidant Capacity Assay for Measuring Lipophilic Antioxidants

Berker

Olgun

Özyurt

et al. 2013

J. Agric. Food Chem.

125

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The Folin-Ciocalteu (FC) method of performing a total phenolics assay, originally developed for protein determination, has recently evolved as a total antioxidant capacity assay but was found to be incapable of measuring lipophilic antioxidants due to the high affinity of the FC chromophore, that is, multivalent-charged phospho-tungsto-molybdate(V), toward water. Thus, the FC method was modified and standardized so as to enable simultaneous measurement of lipophilic and hydrophilic antioxidants in NaOH-added isobutanol-water medium. Optimal conditions were as follows: dilution ratio of aqueous FC reagent with iso-BuOH (1:2, v/v), final NaOH concentration of 3.5 × 10(-2) M, reaction time of 20 min, and maximum absorption wavelength of 665 nm. The modified procedure was successfully applied to the total antioxidant capacity assay of trolox, quercetin, ascorbic acid, gallic acid, catechin, caffeic acid, ferulic acid, rosmarinic acid, glutathione, and cysteine, as well as of lipophilic antioxidants such as α-tocopherol (vitamin E), butylated hydroxyanisole, butylated hydroxytoluene, tertiary butylhydroquinone, lauryl gallate, and β-carotene. The modified FC method reliably quantified ascorbic acid, whereas the conventional method could not. The modified method was reproducible and additive in terms of total antioxidant capacity values of constituents of complex mixtures such as olive oil extract and herbal tea infusion. The trolox equivalent antioxidant capacities of the tested antioxidant compounds correlated well with those found by the Cupric Reducing Antioxidant Capacity reference method.

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“…The black wattle extract used in this study was obtained by using water to leach the materials from black wattle bark, followed by a process of evaporation. The content of polyphenols in the extract was 75%, which was determined according to methods developed by Claderaforteza et al (1995). Comparative biodegradation experiments of black wattle extract (Acacia mearnsii) vs wattle extract (Acacia mimosa) were conducted using natural fresh water from the Jinjiang River in Chengdu, China.…”

Section: Methodsmentioning

confidence: 99%

Effect of Black Wattle (Acacia mearnsii) Extract on Blue‐Green Algal Bloom Control and Plankton Structure Optimization: A Field Mesocosm Experiment

Zhou

Jiang

et al. 2012

Water Environment Research

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A field mesocosm experiment was conducted at the Three Gorges Reservoir to investigate the utility of black wattle extract in controlling blue algal blooms. The mesocosm experiment was divided into two parts: (1) a short-term test to evaluate how black wattle extract inhibits algal blooms in an emergency and (2) a long-term test to evaluate how black wattle extract maintains water quality and prevents algal blooms over a 1-year period. In the short-term test, the results showed that 3 to 4 mg L À1 black wattle extract could reduce algal biomass in 1 week, whereas serious algal blooms occurred in the untreated control mesocosm. More importantly, the long-term test suggested that black wattle extract played a significant role in plankton structure optimization at lower concentrations of 1 to 2 mg L À1 . In this test, phytoplankton diversity increased, with the dominant species shifting from cyanobacteria to diatoms and other algae. Meanwhile, as water quality improved through the presence of plant extract treatment, the numbers of smaller zooplankton decreased and larger species increased. Therefore, this investigation founded a novel nature plant agent that not only has good effects on algal bloom control, but also restores the aquatic ecosystem. Water Environ. Res., 84, 2133Res., 84, (2012.

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Determination of Tannins in White Wines by Thermal Lens Spectrometry

Cited by 7 publications

References 0 publications

Flow injection analysis of gallic acid with inhibited electrochemiluminescence detection

Flow injection analysis of gallic acid with inhibited electrochemiluminescence detection

Modified Folin–Ciocalteu Antioxidant Capacity Assay for Measuring Lipophilic Antioxidants

Effect of Black Wattle (Acacia mearnsii) Extract on Blue‐Green Algal Bloom Control and Plankton Structure Optimization: A Field Mesocosm Experiment

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