A high-performance liquid chromatography method coupled with electrospray ionization-mass spectrometry for the determination of polyphenols in tobacco is studied. The polyphenols are extracted from a tobacco sample by being refluxed in a boiling water bath with 80% methanol and purified by solid-phase extraction with a C18 cartridge. The chlorogenic acid, rutin, scopoletin, caffeic acid, scopol...

A total of 6 Lonicera samples were collected in different ecological areas Chi Linh town, Hai Duong province and Thanh Liem commune, Ha Nam province. The result scientific name identification showed that 4 are macrantha (D. Don) Spreng. species, 1 sample is L. confusaDC. L.japonicaThunb. species. Chlorogenic acid contents all from 0.011 to 0.304%. Results also the chlorogenic content species hi...

Soluble (SP), ionically bound (IBP) and covalently bound (CBP) peroxidases (POD) from artichoke leaves and heads have been characterized for the main biochemical parameters. The three PODs, in both leaves and heads, showed the major apparent catalytic efficiency (vmax,app/Km,app) towards ferulic acid, even though, in some cases, they showed higher affinity (Km,app) for other substrates. In leav...

In the present study we report the isolation of a phenylpropanoid glucoside, plantamajoside, together with rosmarinic acid, chlorogenic acid and luteolin-7-O-monoglucoside. This is the first report of these compounds from Plantago lagopus.

Phenolcarboxylic acid antioxidants do not act in vivo as radical-scavengers in isolation, but rather together with GSH (glutathione), a coantioxidant, they constitute an intricate antioxidant network. Caffeic acid, p-coumaric acid, ferulic acid and chlorogenic acid with or without 2-mercaptoethanol (ME), as a substitute for GSH, was investigated by the induction period (IP) method for polymeriz...

In the present study a simple and highly sensitive RP-HPLC method has been established for simultaneous determination of chlorogenic acid, caffeic acid, vanillic acid and caffeine in coffee samples. The method has been applied to eight different coffees available on the Romanian market which were previously analysed concerning the total polyphenols content and antioxidant capacity. Reduction of...

A simple and rapid HPLC method for determination of chlorogenic acid (5-O-caffeoylquinic acid) in mate tea extracts was developed and validated. The chromatography used isocratic elution with a mobile phase of aqueous 1.5% acetic acid-methanol (85:15, v/v). The flow rate was 0.8 mL/min and detection by UV at 325 nm. The method showed good selectivity, accuracy, repeatability and robustness, wit...

In this report, we presented the profile of polyphenolic substances in flowers, leaves, stalk and roots of Fagopyrum tataricum estimated by using RP-UHPLC-ESI-MS equipment (reversed-phase ultra-high-performance liquid chromatography electrospray ionisation mass spectrometry). The neutral detergent fibre, acid detergent fibre, acid detergent lignin, cellulose and hemicellulose were also determin...

Caffeic acid (3,4-dihydroxycinnamic acid) is a well-known phenolic phytochemical present in many foods, including coffee. Recent studies suggested that caffeic acid exerts anticarcinogenic effects, but little is known about the underlying molecular mechanisms and specific target proteins. In this study, we found that Fyn, one of the members of the non-receptor protein tyrosine kinase family, wa...