Polyphenol content of Marasca sour cherry ecotypes (Prunus cerasus Marasca) and its stability during freezing storage - Pedisić, Sandra; Zorić, Zoran, kemičar; Repajić, Maja; Elez Garofulić, Ivona; Čošić, Zrinka; Dragović-Uzelac, Verica; Levaj, Branka (2019)
The present research was undertaken to evaluate the polyphenol content of two Marasca sour cherry ecotypes (Recta and Brač 2) grown in two areas in Croatia (Zadar and Split), their stability during freezing storage at -18 °C for six months and contribution to antioxidant capacity (AOC), respectively. Polyphenolic content was assessed by high performance liquid chromatography (HPLC UV/VIS PDA) and anthocyanins (ANT), hydroxycinnamic acids (HCA), flavonol glycosides (FG) and flavanols (FLAV) were determined. ANT dominated in fresh and frozen cherry ecotypes (321.90 – 774.61 mg/100 g dm) and cyanidin-3- glucosylrutinoside (CYGR) was present in the highest concentration (223.22 – 501.04 mg/100 g dm). The contents of other phenolics were considerably lower compared to ANT: HCA=40.72 – 86.28 mg/100 g dm, FG=22.34 – 41.03 mg/100 g dm and FLAV=0.16 – 0.59 mg/100 g dm, where major compounds presented in HCA were p-coumaric and neochlorogenic acids, in FG quercetin-3-glucoside and in FLAV catehin. Furthermore, statistical analysis showed that all sour cherry samples significantly differed according to the ANT, HCA, FG and FLAV content (p≤0.01). Generally, ecotype Recta and Zadar growing area had higher polyphenolic content. Freezing storage caused decrease of almost all polyphenolic groups, particularly ANT (16 – 30 %) and HCA (26 – 36 %) while better stability of FG (10.5 – 20 %) and higher variation of FLAV content was observed. For determination of AOC three methods (DPPH, FRAP, ABTS) were used and the AOC was as follows: DPPH=3.284 – 6.38 mmol TE/100 g dm, FRAP=7.18 - 18 mmol TE/100 g dm and ABTS=73.16 - 119.93 mmol TE/100 g dm. The results indicate higher AOC in samples of Brač 2 ecotype from Zadar growing area.
Ovo istraživanje provedeno je radi utvrđivanja razlike u masenom udjelu polifenola dva ekotipa višnje Maraske (Recta i Brač 2) uzgojenih na dva područja u Hrvatskoj (Zadar i Split), utvrđivanja stabilnosti polifenola tijekom skladištenja na -18 ° C tijekom šest mjeseci i doprinosa polifenolnih spojeva antioksidacijskom kapacitetu (AOC). Primjenom tekućinske kromatografije visoke djelotvornosti (HPLC UV/VIS PDA) identificirani su fenolni spojevi iz skupine antocijana (ANT), hidroksicimetnih kiselina (HCA), flavonol glikozida (FG) i flavanola (FLAV). ANT su dominirali u svim uzorcima višanja, svježim i zamrznutim (321,90 - 774,61 mg/100 g st), a u najvećim masenim udjelima određen je cijanidin-3-glukozilrutinozid (CYGR) (223,22-501,04 mg/100 g st). Maseni udjeli drugih polifenolnih spojeva: HCA (40,72–86.28 mg/100 g st), FG (22,34–41,03 mg/100 g st) i FLAV (0,16–0,59 mg/100 g st) bili su znatno niži u odnosu na ANT. Glavni spojevi iz skupine HCA bili su p-kumarinska i neoklorogenska kiselina, iz skupine FG kvercetin-3-glukozid te iz skupine FLAV katehin. Statistička analiza pokazala je da su se svi uzorci višanja značajno razlikovali prema masenom udjelu ANT, HCA, FG, FLAV i AOC (p ≤ 0, 01). Ekotip Recta i zadarsko uzgojno područje su općenito imali veći maseni udio fenolnih spojeva. Skladištenje zamrznutih plodova višnje pri temperaturi od -18 °C tijekom 6 mjeseci uzrokovalo je smanjenje gotovo svih skupina fenolnih spojeva, naročito ANT (16 - 30 %) i HCA (26-36 %) dok je uočena bolja stabilnost FG (10.5 – 20 %) te veće varijacije u masenom udjelu FLAV. Za određivanje AOC korištene su tri metode (DPPH, FRAP, ABTS), a AOC je iznosila kako slijedi: DPPH (3,28- 6,38 mmol TE/100 g st); FRAP (7,18-18 mmol TE/100 g st) te ABTS (73,16-119,93 mmol TE/100 g st). Viši AOC određen je u uzorcima ekotipa Brač 2/Zadar.
Bibliografija: str. 101-102.
Summary ; Sažetak.
Keywords: Višnja maraska -- Prunus cerasus Marasca -- Polifenoli -- Antioksidativno djelovanje -- Uzgojno područje -- Zamrzavanje