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Matrix solid-phase dispersion method coupled with high-performance liquid chromatography for the simultaneous quantification of selected compounds from freeze dry pomegranate juice

Kamal Y. T., Yusufoglu H., Alam P., Fouda A.

Acta Chromatographica

2018

Vol. 30, no. 3

153--157

In this research, a novel method was developed for the matrix solid phase dispersion (MSPD) followed by high-performance liquid chromatography (HPLC) quantification of four marker constituents (vitamin C, gallic acid, rutin, and ellagic acid) in the freeze-dried pomegranate fruit juice. Various MSPD parameters like type of dispersant, sample–dispersant ratio, solvents, its volume, and time of extraction have been optimized after many trials. Furthermore, HPLC method has been developed and optimized for the analysis of all four components. The HPLC separation was achieved using a 250 × 4.6 mm column, particle size of 5 μm, C18 reverse phase column, with a mobile phase consisting of acetonitrile and 0.05% H3PO4, in gradient elution mode with a mobile phase flow rate of 1 mL/min, using ultraviolet (UV)–visible detection at 254 nm. All calibration curves showed good linear regression (r2 ≥ 0.9925) within test ranges. The extraction recoveries of the marker constituents analyzed by MSPD methods were found as ranging from 97.5% to 103.5%. From comparing the chromatograms, validation data and other parameters like time, labor, and feasibility, we found that MSPD technique was most suitable for the analysis as compared to conventional liquid–liquid extraction technique.

Studies on 2,3-Dioxopyrrolidines. Synthesis of Piperazine, Pyrrolo[4,5-b]indole, Pyrazino [5,6-b]indole and Arylazo Derivatives of Amino Acids

Sofan M., Fouda A., Asfah E.

Polish Journal of Chemistry

2004

Vol. 78 / nr 6

837-842

2,3-Dioxopyrrolidines 1 convert into 2,4-diketopiperazines 2 in one pot-reaction with hydrazoic acid. The pyrrolo[4,5-b]indole 6 was obtained by cyclization of p-methoxyphenylhydrazone 4 prepared via Japp-Klingemann reaction of 1a with p-methoxyphenyldiazonium chloride. Compound 5 undergoes Schmidt reaction to give the pyrazino[5,6-b]indole derivative 6. Reaction of 1b with some aryldiazonium chlorides yields arylhydrazono-_-alanines 8 and 9. Phenylhydrazonoglycine derivative 11 was synthesized via Schmidt reaction to 10 with hydrazoic acid.