Abstract
Three plants were studied phytochemically, 44 natural products were isolated. The analytical courses and results were presented in 3 corresponding parts which compose the present PhD Thesis. A brief description of the results follows. Part A u Grape pomace was used as the initial plant material. Firstly, because it is exempt of the juice (which contains a significant amount of hydrocarbons) so it is easier to isolate polyphenolic molecules. Secondly, because essentially it is an agricultural waste which remains in the wineries after the wine-making procedure, with no further utility. u The methanol extract of grape pomace which comes from the grapes of the mandilaria variety exposed to sunlight, was subjected to elaboration with adsorption resins XAD16 and XAD7HP, resulting in the production of 2 fractions, one enriched with polyphenols and one containing the colorants of the grapes, respectively. u The fraction that came from resin XAD16, was rendered with the addition of maltodextrin ...
Three plants were studied phytochemically, 44 natural products were isolated. The analytical courses and results were presented in 3 corresponding parts which compose the present PhD Thesis. A brief description of the results follows. Part A u Grape pomace was used as the initial plant material. Firstly, because it is exempt of the juice (which contains a significant amount of hydrocarbons) so it is easier to isolate polyphenolic molecules. Secondly, because essentially it is an agricultural waste which remains in the wineries after the wine-making procedure, with no further utility. u The methanol extract of grape pomace which comes from the grapes of the mandilaria variety exposed to sunlight, was subjected to elaboration with adsorption resins XAD16 and XAD7HP, resulting in the production of 2 fractions, one enriched with polyphenols and one containing the colorants of the grapes, respectively. u The fraction that came from resin XAD16, was rendered with the addition of maltodextrin to a dry powder of excellent quality, ideal for use in clinical trials. u The fraction that came from resin XAD16 was tested on patients suffering from coronary heart disease and a significant improvement of the function of the endothelium of the coronary artery. u The same fraction along with molecules, fractions and extracts from the mandilaria and assyrtiko varieties, were studied in vitro in relation to their suspensive activity, against mitomycin C and the enzyme topoisomerase I and oxidative factors (bleomycin, H2O2). Interesting results were recorded which may have use in the prevention and cure of certain forms of cancer. u The methanol fraction that resulted from the elaboration with resins XAD16 of the methanol extract of grape pomace Vitis vinifera var mandilaria, was studied phytochemically. u In total 16 secondary metabolites were isolated and identified, which can be categorized to 4 natural products categories. Specifically, they belong to stilbenoids, flavonoids (isoflavonoids, flavanes and flavonoles), phenolic derivatives (phenolic acids, phenylethanols) and nitrogenous bases. u From the isolated products, 2 are encountered for the first time in a plant of the Vitis genus. These are the isoflavonoids genistein and genistin. u From the fraction that resulted from the resin XAD16, a method was developed for the direct isolation of trans-resveratrol, using the FCPC method. u Conclusively, a high technology procedure of exploitation of the wineries waster was developed, during which natural polyphenols are recovered and at the same time thousands tones of grape pomace, which are a source of pollution, are removed from the environment. Part B u The dichloromethane and methanol extract of the plant Polygonum maritimum family Polygonaceae were studied. u The methanol extract was subjected to elaboration with the adsorption resin XAD16 and the resulting fraction was submitted to chromatographic separations. u In total, 14 secondary metabolites were isolated and identified, which can be categorized to 5 natural products categories. Specifically, they belong to flavonoids, phenolic derivatives (arylpropanoids, resorcinols, acetophenones, phenolic glucosides), sesquiterpenoids, phytosterols and lipid acids. u From the isolated molecules, 2 are new natural products, the resorcinol polygonocinol and the acetophenone polygonophenone. u From the isolated molecules, 7 are encountered for the first time in a plant of the Polygonaceae family. These are (+)-cis-8-hydroxycalamene, tetracosyl ferulate, hexacosyl ferulate, octacosyl ferulate, triacontyl ferulate, broussonin B and isotachioside. Part C u The methanol extract of the aerial part of the plant Dorycnium pentaphyllum subsp. herbaceum of the Leguminosae family was studied. u The methanol extract was subjected to elaboration with the adsorption resin XAD16 and the resulted fraction was submitted to chromatographic separations. u In total, 14 secondary metabolites were isolated and identified, which can be categorized to 5 natural products categories. Specifically, they are characterized as flavonoids, phenolic derivatives (phenylbutanones, phenolic glucosides, phenolic acid esters), cyanogenic glucosides, cyclitols and phytosterols. u From the isolated molecules, 1 is a new natural product named dorycnioside, which is a phenylbutanone glucoside. u From the isolated molecules, 2 are encountered for the first time in a plant of the Leguminosae family.These are 4-(4΄-Ο-β-D-glucopyranosylphenyl)-2-butanone and 4-(4΄-Ο-β-glucopyranosyl-3΄-methoxyphenyl)-2-butanone. u From the isolated molecules, (+)-2,3,-dihydromyricetin, kaempferol 3-O-(6΄΄-acetyl)-β-glucopyranoside, lotaustralin and tachioside are encountered for the first time in a plant of the Dorycnium genus. u (+)-2,3-dihydromyricetin was studied in vitro in adenomatic cells of the large intestine (CACO-2) and showed a significant activity in the reduction of their viability.
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