Effect of UV Irradiation on the Nutritional Quality and Cytotoxicity of Apple Juice

Abstract

UV-C irradiation operating at 254 nm wavelength on the polyphenolic and vitamin contents of apple juice including cytotoxicity analysis was studied. UV doses ranging from 0 to 150 mJ·cm were selected for the treatments. Polyphenols (catechin, epicatechin, chlorogenic acid, and phloridzin) and vitamins (riboflavin, thiamine hydrochloride, pyridoxal hydrochloride, pyridoxine, pyridoxamine dihydrochloride, cyanocobalamin, choline chloride, biotin, niacin, and niacinamide) were chemically profiled. It was observed that UV treatment of apple juice at disinfection doses caused minor reductions (p < 0.05) in the concentrations of two main polyphenols (i.e., chlorogenic acid and epicatechin). In contrast, significant (p < 0.05) decreases in vitamin concentrations were observed (p < 0.05). The irradiated juice was evaluated for cytotoxic effects. The irradiated apple juice showed no cytotoxic effects on normal intestinal cells, and both irradiated and nonirradiated samples are significantly comparable in inhibiting the growth of human colon cancer cells. Overall, these results indicated that UV-C treatment of apple juice neither significantly degraded polyphenols nor generated cytotoxic compounds.

UV‐C treatment on the safety of skim milk: Effect on microbial inactivation and cytotoxicity evaluation

“…Dose verification was not conducted nor was dosage reported by the authors. Consideration of optical attenuation coefficients of the test fluid as wells as verification of UV fluence is fundamentally important to effective inactivation of food borne illnesses in opaque liquid foods (Caminiti et al, ; Islam, Patras, Pokharel, Vergne, et al, ; Unluturk, Atilgan, Baysal, & Unluturk, ). It is quite evident that system design of the continuous flow UV‐C reactor provided adequate mixing that resulted in log 10 linear inactivation of microbes even up to 5 log 10 or more for E. coli and S .…”

UV‐C Irradiation on the Quality of Green Tea: Effect on Catechins, Antioxidant Activity, and Cytotoxicity

“…In our previous studies with apple juice, the level of polyphenols were relatively stable at a fluence of 40 mJ/cm 2 . In contrast, minor reductions ( P < 0.05) were observed at higher doses (150 mJ/cm 2 ) (Islam et al., ; Islam et al., ). In another study, UV‐C irradiation either increased or did not significantly decrease the polyphenolic content of papaya fruit (Rivera‐Pastrana, Gardea, Yahia, Martínez‐Téllez, & González‐Aguilar, ); therefore, minor changes in the polyphenolic content are predicted when fruits, fruit juices, and tea are treated with UV‐C technology.…”

“…UV fluence was quantified based on the log‐reduction of bacteriophage MS2 in the test fluid; a UV fluence of 110 mJ/cm 2 yields a 5‐log reduction. Our previous studies have also demonstrated that MS2 can be used to validate and verify UV fluence in an absorbing fluid; MS2 inactivation has a linear response to UV fluence (Islam et al., ; Islam et al., ).…”

“…In order to test the conversion of EC to (+)‐catechin and (‐)‐catechin, a collimated beam system was used for UV irradiation (Islam et al., ). A 45 μg/mL EC solution was prepared in deionized water.…”

“…Cells were routinely cultivated in T flasks from Corning (Corning, NY, U.S.A.). The cell experiment was described previously (Islam et al., ). Ethyl acetate was used to produce extracts from the tea samples, and the extracts were diluted 50‐fold to 12.5‐fold.…”