Vpliv ekstraktov pečenega govejega mesa na znotrajcelično oksidacijo v kvasovkah vrste Saccharomyces cerevisiae

Delić, Arnela (author), Jamnik, Polona (mentor), Polak, Tomaž (co-mentor)

Namen magistrske naloge je bil ugotoviti vpliv ekstraktov heterocikličnih aminov (HCA) iz govejih pleskavic, pečenih na dvoploščnem žaru pri petih različnih temperaturah, in sicer: 120 °C, 160 °C, 180 °C, 220 °C in 260 °C, na modelnem organizmu - kvasovki Saccharomyces cerevisiae. Goveje pleskavice so bile pripravljene v dveh skupinah A in B, in sicer tako, da so bile pleskavice A pečene do središčne temperature (Ts) = 72 °C, medtem ko so se pleskavice B pekle 5 minut. Najprej smo analizirali prisotnost HCA v mesnih ekstraktih, kjer smo pri vseh vzorcih določili relativno največ PhIP, sledil je MeIQx v veliko nižji koncentraciji. S pomočjo kvasovke Saccharomyces cerevisiae smo preverili vpliv ekstraktov HCA iz pečenih govejih pleskavic na celični ravni. Kvasovke smo inkubirali v pufru PBS pri 28 °C in 220 obr./min ter jih za 2 uri izpostavili raztopini ekstrakta HCA v različnih koncentracijah. Po 2-urni izpostavitvi smo izmerili nivo znotrajcelične oksidacije z uporabo barvila 2',7'-diklorofluorescein ter vsebnost glutationa v reducirani obliki. Iz rezultatov lahko zaključimo, da dodatek raztopine ekstrakta HCA iz govejih pleskavic tako za vzorce, pečene do središčne temperature 72 °C kot tudi za vzorce, pečene 5 minut, v uporabljenih koncentracijah ne inducira oksidativnega stresa pri kvasovki Saccharomyces cerevisiae in nima vpliva na vsebnost reducirane oblike glutationa.

• Language: Slovenian
• Keywords: goveje meso, toplotna obdelava, heterociklični amini, karcinogene spojine, mutagene spojine, oksidativni stres, znotrajcelična oksidacija, Saccharomyces cerevisiae
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: BF - Biotechnical Faculty
• Publisher: [A. Delić]
• Year: 2019
• PID: 20.500.12556/RUL-111552
• UDC: 637.514.5:641.526.5:547.554:577.1
• COBISS.SI-ID: 5106552
• Publication date in RUL: 03.10.2019

Secondary language

• Language: English
• Title: Effects of roast beef extracts on intracellular oxidation in the yeast Saccharomyces cerevisiae

Abstract

The aim of this master thesis was to determine an influence of extract heterocyclic amines (HCA) from beef patties, grilled on a double-plate at five different temperatures 120 °C, 160 °C, 180 °C, 220 °C in 260 °C using the yeast Saccharomyces cerevisiae as a model organism. Beef patties were grilled to a core temperature 72 °C (group A) or a duration of a grilling was exactly 5 minutes (group B). Firstly, a presence of HCA in meat was analysed. Interestingly, a large quantity of PhIPs was detected in all beef patties, followed by MeIQx in very small concentrations. An effect of HCA extracts from the meat was investigated using yeast Saccharomyces cerevisiae on a cellular level. Yeast was incubated in PBS buffer at 28 °C at 220 rpm and than exposed for 2 hours to a solution of HCA extract at different concentrations. After 2-hour exposure we measured level of intracellular oxidation using 2',7' dichlorofluorescein and the content of reduced intracellular glutathione (GSH). Results showed that solutions of HCA extract from beef patties, treated under different conditions, do not induce an oxidative stress in Saccharomyces cerevisiae. Furthermore, HCA extracts had no effect on reduced intracellular glutathione content.

• Keywords: beef meat, grilling, heterocyclic amines, cancerogens, mutagens, oxidative stress, intracellular oxidation, Saccharomyces cerevisiae