Changes in antioxidant properties of pepper leaves (Capsicum annuum L.) upon UV radiation

Year 2024, Volume: 11 Issue: 2, 333 - 340, 03.06.2024

Valér Góra Kristóf Csepregi

https://doi.org/10.21448/ijsm.1430542

Abstract

Bell pepper (Capsicum annuum) is one of the most popular vegetables consumed worldwide. The leaves of pepper are rich in phenolics, including phenolic acids and flavonoids. These compounds are well known for their ultraviolet (UV) absorbing and antioxidant properties. While the change of the phenolic pattern is an intensive research subject, it is not yet well-known in pepper leaves, particularly in outdoor conditions. In this experiment, we examined the effect of UV radiation on the leaves of outdoor grown peppers, focusing on the UV-absorbing properties and antioxidant capacities. Three different total antioxidant capacity (TAC) measurements have been compared: (I) Folin-Ciocalteu Reactivity (FC), (II) Ferric Reducing Antioxidant Power (FRAP) and (III) Trolox Equivalent Antioxidant Capacity (TEAC). Moreover, non-enzymatic hydrogen peroxide scavenging antioxidant capacity was measured. Significant increase was detected only in FRAP, suggesting an elevation exclusively in the level of phenolic acids in case of UV exposed outdoor grown pepper leaves.

Keywords

Antioxidant capacity, Phenolic compounds, Capsicum annuum, Ultraviolet radiation, Bell pepper

Ethical Statement

Department of Biology, Faculty of Sciences, University of Pécs, H-7624 Pécs, Ifjúság útja 6. Hungary

Supporting Institution

National Research, Development and Innovation Office (grant number FK-147093) and the János Bolyai Research Scholarship of the Hungarian Academy of Sciences (BO/00362/20/4).

Project Number

grant number FK-147093, and BO/00362/20/4

References

• Agati, G., & Tattini, M. (2010). Multiple functional roles of flavonoids in photoprotection. The New Phytologist, 186(4), 786-793.
• Agati, G., Azzarello, E., Pollastri, S., & Tattini, M. (2012). Flavonoids as antioxidants in plants: location and functional significance. Plant science, 196, 67-76.
• Agati, G., Brunetti, C., Fini, A., Gori, A., Guidi, L., Landi, M., ... & Tattini, M. (2020). Are flavonoids effective antioxidants in plants? Twenty years of our investigation. Antioxidants, 9(11), 1098.
• Assefa, S.T., Yang, E. Y., Asamenew, G., Kim, H.W., Cho, M.C., & Lee, J. (2021). Identification of α-glucosidase inhibitors from leaf extract of pepper (Capsicum spp.) through metabolomic analysis. Metabolites, 11(10), 649.
• Ballaré, C.L. (2003). Stress under the sun: spotlight on ultraviolet-B responses. Plant Physiology, 132(4), 1725-1727.
• Casañal, A., Zander, U., Muñoz, C., Dupeux, F., Luque, I., Botella, M. A., ... & Marquez, J. A. (2013). The strawberry pathogenesis-related 10 (PR-10) Fra a proteins control flavonoid biosynthesis by binding to metabolic intermediates. Journal of Biological Chemistry, 288(49), 35322-35332.
• Czégény, G., Wu, M., Dér, A., Eriksson, L.A., Strid, Å., & Hideg, É. (2014). Hydrogen peroxide contributes to the ultraviolet-B (280–315 nm) induced oxidative stress of plant leaves through multiple pathways. FEBS letters, 588(14), 2255-2261.
• Csepregi, K., & Hideg, É. (2016). A novel procedure to assess the non-enzymatic hydrogen-peroxide antioxidant capacity of metabolites with high UV absorption. Acta Biologica Hungarica, 67, 447-450.
• Csepregi, K., & Hideg, É. (2018). Phenolic compound diversity explored in the context of photo‐oxidative stress protection. Phytochemical Analysis, 29(2), 129-136.
• Csepregi, K., Neugart, S., Schreiner, M., & Hideg, É. (2016). Comparative evaluation of total antioxidant capacities of plant polyphenols. Molecules, 21(2), 208.
• Csepregi, K., Teszlák, P., Kőrösi, L., & Hideg, É. (2019). Changes in grapevine leaf phenolic profiles during the day are temperature rather than irradiance driven. Plant Physiology and Biochemistry, 137, 169-178.
• Deng, Y., & Lu, S. (2017). Biosynthesis and regulation of phenylpropanoids in plants. Critical Reviews in Plant Sciences, 36(4), 257-290.
• Hectors, K., Van Oevelen, S., Geuns, J., Guisez, Y., Jansen, M. A., & Prinsen, E. (2014). Dynamic changes in plant secondary metabolites during UV acclimation in Arabidopsis thaliana. Physiologia Plantarum, 152(2), 219-230.
• Hernández, I., Alegre, L., Van Breusegem, F., & Munné-Bosch, S. (2009). How relevant are flavonoids as antioxidants in plants?. Trends in plant science, 14(3), 125-132.
• Jenkins, G.I. (2014). The UV-B photoreceptor UVR8: from structure to physiology. The Plant Cell, 26(1), 21-37.
• Kim, W.R., Kim, E.O., Kang, K., Oidovsambuu, S., Jung, S.H., Kim, B.S., ... & Um, B.H. (2014). Antioxidant activity of phenolics in leaves of three red pepper (Capsicum annuum) cultivars. Journal of Agricultural and Food Chemistry, 62(4), 850-859.
• Klem, K., Holub, P., Štroch, M., Nezval, J., Špunda, V., Tříska, J., ... & Urban, O. (2015). Ultraviolet and photosynthetically active radiation can both induce photoprotective capacity allowing barley to overcome high radiation stress. Plant Physiology and Biochemistry, 93, 74-83.
• Morales, L.O., Brosché, M., Vainonen, J., Jenkins, G. I., Wargent, J.J., Sipari, N., ... & Aphalo, P.J. (2013). Multiple roles for UV RESISTANCE LOCUS8 in regulating gene expression and metabolite accumulation in Arabidopsis under solar ultraviolet radiation. Plant physiology, 161(2), 744-759.
• Morales, L.O., Tegelberg, R., Brosche, M., Keinänen, M., Lindfors, A., & Aphalo, P.J. (2010). Effects of solar UV-A and UV-B radiation on gene expression and phenolic accumulation in Betula pendula leaves. Tree Physiology, 30(7), 923-934.
• Rice-Evans, C., Miller, N., & Paganga, G. (1997). Antioxidant properties of phenolic compounds. Trends in Plant Science, 2(4), 152-159.
• Rizzini, L., Favory, J.J., Cloix, C., Faggionato, D., O’hara, A., Kaiserli, E., ... & Ulm, R. (2011). Perception of UV-B by the Arabidopsis UVR8 protein. Science, 332(6025), 103-106.
• Rodríguez-Calzada, T., Qian, M., Strid, Å., Neugart, S., Schreiner, M., Torres-Pacheco, I., & Guevara-González, R.G. (2019). Effect of UV-B radiation on morphology, phenolic compound production, gene expression, and subsequent drought stress responses in chili pepper (Capsicum annuum L.). Plant Physiology and Biochemistry, 134, 94-102.
• Siipola, S.M., Kotilainen, T., Sipari, N., Morales, L.O., Lindfors, A.V., Robson, T.M., & Aphalo, P.J. (2015). Epidermal UV‐A absorbance and whole‐leaf flavonoid composition in pea respond more to solar blue light than to solar UV radiation. Plant, cell & environment, 38(5), 941-952.
• Yang, B., Liu, H., Yang, J., Gupta, V.K., & Jiang, Y. (2018). New insights on bioactivities and biosynthesis of flavonoid glycosides. Trends in food science & technology, 79, 116-124.