cytellin and erythrodiol

The aim of this work was to study the chemical characteristics of two Tunisian cultivars, namely Dhokar and Gemri-Dhokar, to analyse the fatty acids, sterols, triacylglycerols, triterpenic alcohols, and to determine the phenolic composition and oxidative stability.. Among the rare varieties, Gemri-Dhokar olive oil had the highest value of oleic acid (69.39%) whereas Dhokar oil was noteworthy for its lower content of phenolic compounds (94.56 mg kg(-1) gallic acid equivalents of oil) and presented the highest level of palmitic acid (19.37%). The main sterols found in all olive oil samples were β-sitosterol and Δ5-avenasterol, whereas cholesterol and 24-methylenecholesterol were also found in all samples but in lower amounts. Two triterpenic dialcohols (erythrodiol and uvaol) were also detected and their content ranged from 1.45 to 2.30%, in Gemri-Dhokar and Dhokar olive oil, respectively. Ten phenolic compounds were identified. In all samples, the main phenols found were oleuropein aglycon and pinoresinol. These phenolic compounds showed significant correlations with oxidative stability.. The analytical parameters of two oils that were determined in this study were greatly influenced by genetic factors (cultivar).

Topics: Alcohols; Drug Stability; Fatty Acids; Furans; Iridoid Glucosides; Iridoids; Lignans; Oleanolic Acid; Olive Oil; Oxidation-Reduction; Palmitic Acid; Phenols; Phytosterols; Plant Oils; Pyrans; Sitosterols; Species Specificity; Triglycerides; Triterpenes; Tunisia

Triterpenoid compounds found in free and ester forms in extracts of entire fruits and leaves and in fruit and leaf cuticular waxes of bilberry (Vaccinium myrtillus L.) collected in Finland and Poland were identified and quantitated by gas chromatography-mass spectrometry coupled to a flame ionization detector (GC-MS/FID). The main bilberry triterpenoid profile consisted of α- and β-amyrin, α- and β-amyrenone, campesterol, cholesterol, citrostadienol (in berries), cycloartanol, erythrodiol, lupeol, 24-methylenecycloartanol, sitosterol, sitostanol, stigmasterol, stigmasta-3,5-dien-7-one, uvaol, oleanolic and ursolic aldehydes, and oleanolic, ursolic, 2α-hydroxyoleanolic, and 2α-hydroxyursolic acids. Friedelin and D:A-friedooleanan-3β-ol were found only in Finnish plants, whereas D:C-friedours-7-en-3β-ol and taraxasterol were found only in Polish plants. To our knowledge, this is the first thorough description of triterpenoid compounds in this species. The presented results revealed that the triterpenoid profile of bilberry varied considerably between different organs of the plant, regardless of the plant origin, as well as between plant samples obtained from the two geographical locations.

Topics: Anthocyanins; Cholesterol; Finland; Fruit; Gas Chromatography-Mass Spectrometry; Molecular Structure; Oleanolic Acid; Phytosterols; Plant Extracts; Plant Leaves; Poland; Sitosterols; Triterpenes; Vaccinium myrtillus