Phenolic acids high performance liquid

HPLC) for phenolic acids analysis. When procedure (ii) was applied, the ion-exchange resin was separated from the methanol phase and eluted with three 40 ml aliquots of 80% methanol. The resin bead eluates were evaporated to dryness and subjected to spectrophotometry (Shimadzu UV 160 spectrophotometer) for total phenolics and high-performance liquid chromatography (HPLC) for phenolic acids analysis. 

Torres, A.M., Mau-Lastovicka, T., and Rezaaiyan, R. 1987. Total phenolics and high-performance liquid chromatography of phenolic acids of avocado. J. Agric. Food Chem. 35 921-925. 

Li P, Wang XQ, Wang HZ and Wu YN. 1993. High performance liquid chromatographic determination of phenolic acids in fruits and vegetables. Biomed Environ Sci 6(4) 389-398. 

G. Shui and L.P. Leong, Separation and determination of organic acids and phenolic compounds in fruit juices and drinks by high-performance liquid chromatography. J. Chromatogr.A 977 (2002) 89-96. 

High-performance liquid chromatography (HPLC) techniques are widely used for separation of phenolic compounds. Both reverse- and normal-phase HPLC methods have been used to separate and quantify PAs but have enjoyed only limited success. In reverse-phase HPLC, PAs smaller than trimers are well separated, while higher oligomers and polymers are co-eluted as a broad unresolved peak [8,13,37]. For our reverse-phase analyses, HPLC separation was achieved using a reverse phase. Cl8, 5 (Jtm 4.6 X 250 mm column (J. T. Baker, http //www.mallbaker.com/). Samples were eluted with a water/acetonitrile gradient, 95 5 to 30 70 in 65 min, at a flow rate of 0.8 mL/min. The water was adjusted with acetic acid to a final concentration of 0.1%. All mass spectra were acquired using a Bruker Esquire LC-MS equipped with an electrospray ionization source in the positive mode. 

Schieber, A., Keller, P., and Carle, R., Determination of phenolic acids and flavonoids of apple and pear by high-performance liquid chromatography, J. Chromatogr. A, 910, 265, 2001. 

Shakya, R., Navarre, D. A. (2006). Rapid screening of ascorbic acid, glycoalkaloids, and phenolics in potato using high-performance liquid chromatography. J. Agric. Food Chem., 54, 5253-5260. 

C Regnault-Roger, R Hadidane, JF Biard, K Boukef. High performance liquid and thin layer chromatographic determination of phenolic acids in palm (Phoenix dactilifera) product. Food Chem 25 61-71, 1987. 

A Seo, CV Morr. Improved high-performance liquid chromatographic analysis of phenolic acids and isoflavonoids from soybean protein products. J Agric Food Chem 32 530-533, 1984. 

Yu J, Vasanthan T, Temelli F. 2001. Analysis of phenolic acids in barley by high-performance liquid chromatography. J Agric Food Chem 49 4352-4358. 

Ratanathanawongs and Crouch [19] have described an on-line post-column reaction based on air-segmented continuous flow for the determination of phenol in natural waters by high performance liquid chromatography. The reaction used was the coupling of diazotised sulphanilic acid with the phenol to form high coloured azo dyes. The detection limit for phenol was 17pg L 1 which represents a 16-fold improvement over determination of phenol with ultraviolet detection. 

Glowniak, K., Zgorka, G., and Kozyra, M. 1996. Solid-phase extraction and reversed-phase high-performance liquid chromatography of free phenolic acids in some Echinacea species. J. Chromatogr. A 730, 25-29. 

Variyar, P.S. and Bandyopadhyay, C. (1 995) Estimation of phenolic acids in cinnamon, clove, cardamom, nutmeg and mace by high performance liquid chromatography. Journal of Spices and Aromatic Crops 4(2), 129-134. 

Parejo et al. (2004) identified caffeoyl-quinic acids, dicaffeoylquinic acids, flavonoids and rosmarinic acid among ten main antioxidant phenolic compounds from bitter fennel, F. vulgare, using a simple high-performance liquid chromatography (HPLC). Distilled fennel was found to contain a higher proportion of antioxidant phenolic compounds than non-distilled plant material. 

Gioacchin, A.M. Roda, A. Galletti, G.C. Bocchini, P. Manetta, A.C. Baraldini, M. 1996. High-performance liquid chromatographic-electrospray mass spectrometric analysis of phenolic acids and aldehydes. J. Chromatogr. A. 730 31-37. 

Haghi, G. Hatami, A. 2010. Simultaneous quantification of flavonoids and phenolic acids in plant materials by a newly developed isocratic high-performance liquid chromatography approach. J. Agric. Food Chem. 58 10812 10816. 

Svedstrom, U. Vuorela, H. Kostiainen, R. Laakso, L Hiltunen, R. 2006. Fractionation of polyphenols in hawthorn into polymeric procyanidins, phenolic acid, and flavonoids prior to high-performance liquid chromatographic analysis. J. Chromatogr. A. 1112 103-111. 

Vanbeneden, N., Delvaux, E, Delvaux, ER. (2006). Determination of hydroxycinnamic acids volatile phenols in wort and beer by isocratic high-performance liquid chromatography using electrochemical detection. J. Chromatogr. A, 1136, 237-242. 

The developments of the Lewis base-modified zirconia and mixed-oxide containing zirconia as stationary phases for high-performance liquid chromatography (HPLC) are reviewed. In this context, the preparation methods of porous spherical zirconia, and zirconia supports for HPLC based on modification with fluoride, phosphate, phos-phonate, carboxylic acid, phenols, and protein, as well as cyclodextrin derivative, are covered. The application of modified-zirconia in capillary electrochromatography (CEC) is also discussed. 

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