Vpliv obsevanja jabolk s svetlobo različnih valovnih dolžin na njihov bioaktivni potencial

Goršek, Sara (author), Jeršek, Barbka (mentor), Piskernik, Saša (co-mentor)

Uživanje jabolk ima veliko pozitivnih učinkov na zdravje ljudi. Z visoko vsebnostjo antioksidantov jabolka zmanjšujejo tveganje za pojav različnih bolezni. Zanimalo nas je, ali svetloba izbranih valovnih dolžin (420 nm, 450 nm) med 18 dnevnim skladiščenjem pri 10 °C pripomore k povečani tvorbi flavonoidov ter večjemu antioksidativnemu potencialu (AOP) jabolk (Malus domestica) sorte Angold ter če ima spremenjena vsebnost fenolnih spojin vpliv na protibakterijsko aktivnost ter na adhezijo bakterij vrste L. monocytogenes na jabolko. Ugotovili smo, da sta imela ekstrakta jabolčnih lupin, ki sta bila 18 dni skladiščena pri 420 nm in 450 nm (E420 in E450) manjšo vsebnost flavonoidov kot ekstrakt jabolčnih lupin svežih jabolk (E0) in ekstrakt jabolčnih lupin jabolk, ki so bila 18 dni skladiščena v temi (Et). Vrednosti AOP ekstraktov jabolčnih lupin se niso razlikovale glede na valovno dolžino svetlobe. Protibakterijska aktivnost proti bakterijam vrste L. monocytogenes je bila boljša pri ekstraktih jabolčnih lupin E420 in E450 kot pri ekstraktih E0 in Et. Iz tega lahko sklepamo, da obsevanje jabolk z modro svetlobo vpliva na večjo vsebnost bioaktivnih spojin, ki pa niso flavonoidi. Adhezija bakterij vrste L. monocytogenes na jabolkih se je zmanjšala po 48-urni in 72-urni inkubaciji pri svežih jabolkih, jabolkih, ki so bila 18 dni skladiščena pri 420 nm in jabolkih, ki so bila 18 dni skladiščena pri 450 nm. Pri jabolkih, ki so bila 18 dni skladiščena v temi, smo zmanjšanje adhezije zaznali po 72-urni inkubaciji. Zaključimo lahko, da modra svetloba uporabljena med skladiščenjem jabolk, vpliva na povečanje bioaktivnega potenciala jabolk, vendar bi bile potrebne nadaljnje raziskave.

• Language: Slovenian
• Keywords: jabolka, Malus domestica, ekstrakt jabolčnih lupin, obsevanje jabolk, vsebnost flavonoidov, MIC, antioksidativni potencial, adhezija na jabolku
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: BF - Biotechnical Faculty
• Place of publishing: Ljubljana
• Publisher: [S. Goršek]
• Year: 2021
• PID: 20.500.12556/RUL-130607
• UDC: 634.11:641.1:577.1:579.67
• COBISS.SI-ID: 76694275
• Publication date in RUL: 16.09.2021

Secondary language

• Language: English
• Title: The effect of apple irradiation with light of different wavelengths on their bioactive potential

Abstract

Eating apples has many positive effects on human health. Due to a high content of antioxidants apples reduce the risk of various deseases. We were investigating whether irradiation of apples with blue lights of selected wavelengths (420 nm and 450 nm) during 18 days of storage at 10 °C contributed to an increased flavonoid content and increased antioxidant potential (AOP) of apples (Malus domestica) cv. Angold and if altered content of phenolic compounds affects antibacterial activity against L. monocytogenes and the ability of L. monocytogenes to adhere to the apple. Apple peel extracts made from apples stored at 420 nm and 450 nm (E420 and E450) for 18 days had lower flavonoid content than fresh apple peel extract (E0) and apple peel extract stored for 18 days in the dark (Et). The AOP values of the apple peel extracts did not differ between wavelengths. E420 and E450 apple peel extracts were more efficient against L. monocytogenes than E0 and Et apple peel extracts. From these results we can conclude that irradiation of apples with blue light increased the content of bioactive compounds other than flavonoids. Decreased adhesion of L. monocytogenes on apples was detected after 48-hour and 72-hour incubation of fresh apples, apples stored for 18 days at 420 nm and apples stored for 18 days at 450 nm. In apples stored for 18 days in the dark, however, a decrease in adhesion was observed after 72-hours of incubation. We can conclude that blue light applied during apples storage increases the bioactive potential of apples, but further investigations are needed.

• Keywords: apples, Malus domestica, apple peel extracts, wavelength irradiation, flavonoid content, MIC, antioxidant potential, adhesion on apple