The aim of the present study was to improve the recovery of polyphenols from olive leaves (OL) by optimizing a multistage extraction scheme; provided that the olive leaves have been previously steam blanched. The maximum total phenol content expressed in ppm caffeic acid equivalents was obtained at pH 2, particle size 0.315 mm, solid-liquid ratio 1:7 and aqueous ethanol concentration 70% (v/v)....

Sage (Salvia officinalis L.) is a popular herb which is native to the Mediterranean region and cultivated worldwide. Sage is an important source of antioxidants used as preservatives and has wider implications for the dietary intake of natural antioxidants.1,2 This antioxidant effect has been attributed to the main phenolic components, caffeic acid dimer – rosmarinic acid1 and flavonoids, being...

Enzymatic extraction was investigated to improve the quality of black tea extracts with pretreatment of pectinase and tannase independently, successively and simultaneously. Pectinase improved the extractable-solids-yield (ESY) up to 11.5%, without much of an improvement in polyphenols recovery, while tannase pre-treatment showed a significant improvement in polyphenols recovery (14.3%) along w...

The purpose of the present study is to survey the extraction conditions and explore the antioxidant potential of the wild herb Cistus incanus, which is non-traditional in Bulgarian ethnomedicine and widespread in the Strandja Mountain. The influence of the extraction time (0-500 min) and solvent composition (0-50% ethanol in water) on the polyphenols, flavonoid yields and on the antioxidant cap...

The abundant fruit hulls of tea-oil tree (Camellia oleifera) are still underutilized and wastefully discaded to pollute the environment. In order to solve this problem and better utilize the fruit hulls of C. oleifera, a microwave-assisted extraction system was used to extract their polyphenols using water as the extraction solvent. A central composite design (CCD) was used to monitor the effec...

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...