The effect of postharvest ultraviolet irradiation on the content of antioxidant compounds and the activity of antioxidant enzymes in tomato

Abstract

The effect of different doses of long-wavelength UV-A (320 nm-400nm) irradiation on physicochemical and antioxidant characteristics of tomatoes grown on the territory of the Russian Federation was studied. The obtained results show that this kind of processing does not cause deterioration of qualitative parameters of vegetables (texture, color, soluble solids content, titratable acidity). It was established that the total content of phenolic compounds, carotenoids and flavonoids increases (p-value<0.05) in tomatoes at all the investigated wavelengths (353 nm, 365 nm and 400 nm), while the content of chlorophylls reacts ambiguously: at some wavelengths, it increases, at other, it decreases. The maximum increase in antioxidant activity, as compared to untreated samples, is observed in tomatoe samples irradiated for 360 min within the range of 365 nm. For different types of tomatoes, the increment for common content of phenolic compounds is-42.9-55.0 %, carotenoids-24.0-56.0 %, flavonoids-28.0-33.0 %, β-carotene-70.9-71.6 %, lycopene-62.6-69.0 %, lutein-64.8-72.0 % from original. The studies reveal some potential of post-harvest ultraviolet irradiation (A-range) of tomatoes to increase their antioxidant activity. However, more research is needed to confirm this fact and the possibility to develop some technology.

Anything New under the Sun? An Update on Modulation of Bioactive Compounds by Different Wavelengths in Agricultural Plants

“…However, after 360 min of irradiation, no difference among the three wavelengths was detected, with the only exception of flavonoid content of cv. Budenovka, which was unchanged following the irradiation with the shortest wavelength [ 195 ]. Grape berries ( Vitis vinifera L. cv.…”

“…studied (Budenovka, Bull Heart, and Gina). However, 353 nm was never effective in inducing modification in carotenoid content, while 365 nm played a positive influence on carotenoid levels already after 10 min of irradiation, but only in cv Budenovka [ 195 ], again indicating the importance of both light energy and genotype in determining the outcome. The same authors also found a structure-dependent response to the three UV-A radiations employed in their research.…”

“…A study carried out in fruits of three tomato cultivars (Budenovka, Bull Heart, and Gina) highlighted the dependence of chlorophyll accumulation on UV-A wavelength. Indeed, 180- and 360-min treatment with 365 nm increased chlorophyll concentration in all cultivars, while the highest wavelength induced a positive effect only after 360-min exposure and only for two of the three cultivars, while 353 nm was always ineffective [ 195 ]. A similar finding was also reported by Brazaitytė et al [ 188 ] in red pak choi seedlings grown under supplemental UV-A radiation (366, 390, or 402 nm, the latter already falling into the blue region of the spectrum) given at two different doses (6.2 or 12.4 μmol m −2 s −1 ).…”

Non-thermal Technologies for Food Processing

“…Therefore, it can be used for many applications in food industries. Recent studies have shown that ultraviolet treatment of fresh fruits and vegetables (after harvesting) not only results in microbial inactivation but also increases the antioxidant content and enhances its activity ( 187 ). UV treatment is also used for the reduction of toxins in food ( 188 ).…”

Tomato Cultivation in a Plant Factory with Artificial Light: Effect of UV-A Irradiation During the Growing Period on Yield and Quality of Ripening Fruit

“…In our study, it was shown that the TSS content increased under the influence of UV irradiation, as in Kasim and Kasim (2015), even though the harvested fruits were not UV-irradiated. Cote et al (2013) reported that irradiation of postharvest fruits with UV-C radiation for 2 min (peak emission: 254 nm; 33 W•m −2 ) slightly reduced the TA and Dyshlyuk et al (2020) reported that the TA was hardly affected by UV-A radiation (UV intensity: 353 nm, 365 nm and 400 nm; UV irradiated continuously for 10 min, 180 min, and 360 min at the following doses: 0.33, 0.28 and 0.28 W•m −2 , respectively for UV intensity types). It was considered that the increase in the TA was related to the irradiation time of UV-A and the irradiation intensity because it was different from the results of this study, in which the TA increased when irradiated with UV-A.…”