Naslov
Polyphenolic profile of white and red grape skin extracts

Autori
Katalinić, Višnja ; Generalić, Ivana ; Ljubenkov, Ivica ; Skroza, Danijela ; Pezo, Ivan ; Miloš, Mladen ; Boban, Mladen

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Book of Abstracts of the Congress of the Croatian Society of Biochemistry and Molecular Biology with international participation- HDBMB2008 / Strelec, Ivica ; Glavaš-Obrovac, Ljubica - Osijek : Grafika Osijek, 2008, 90-90

ISBN
978-953-95551-2-0

Skup
Congress of the Croatian Society of Biochemistry and Molecular Biology with international participation- HDBMB2008

Mjesto i datum
Osijek, Hrvatska, 17.07.2008. - 20.07.2008

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
polyphenols; flavonoids; stilbenes; resveratrol; grape skin extracts

Sažetak
Intake of food modulates metabolic processes and influences health, the organism being supplied by different bioactive molecules essential for life. In last years great attention is being paid to plant polyphenols and their antioxidative properties. The aim of this study is to determine polyphenolic profile, and antioxidative properties of red and white grape skin extracts. The research includes 10 native and 2 introduced* grape varieties (White: Kujundžuša, Zlatarica, Medna, Kuć, Maraština and Rkaciteli* ; Red: Vranac, Trnjak, Rudežuša, Babić, Lasin and Merlot*). The grapes were harvested at the stage of technological maturity. All grape skin extracts have been analyzed because of their phenolic content. Antioxidant properties are determined as a free radical scavenging ability (DPPH method) and a ferric reducing/antioxidant power (FRAP method). The research of polyphenolic profile of berry skin extracts has shown difference in the mass amounts of total phenols, flavonoids and non-flavonoids among selected grape cultivars, as expected. The high antioxidant capacity of tested extracts has been observed and related to the presence of a mixture of polyphenolic compounds with good antioxidant properties. Identification of individual stilbenes, and flavonoids have been obtained using HPLC-RP-DAD technique. It is pointed out that, between selected grape varieties, procyanidin B1, (-)-epigallocatechin and (+)-catechin are only present in the white grape skin extracts. On the other hand (-)-epicatechin, beside Kujundžuša cv., is mostly the characteristic of skin extracts of red grape cultivars. Procyanidin B2 and (-)-epicatechin gallate have been determined in all grape skin extracts. The presence of quercetin glycoside depends on cultivars. Because of the great interest in recent times for resveratrol and its derivatives a special attention has been given to stilbene compounds. Free resveratrol monomers have been found in all analyzed white and red, grape skin extracts. The presence of piceid has been confirmed in skin extracts of several grape varieties, mostly red. Astringin, usually found in grape leafs and stems, has been identified in the skin extracts of two white and two red grape cultivars. According to the obtained results it can be concluded that grape skin extracts can be a good dietary source of biologically interesting flavonoids and stilbenes. The grapes’ processing should be based on taking advantage of efficiently exploiting natural potential of grape skins.

Izvorni jezik
Engleski

Znanstvena područja
Prehrambena tehnologija

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