Estimating flavonoid oxidation potentials: mechanisms and charge-related regression models

Arh Hig Rada Toksikol. 2023 Jun 26;74(2):99-105. doi: 10.2478/aiht-2023-74-3721. eCollection 2023 Jun 1.

Abstract

In this paper, I tested our quadratic regression models for the estimation of flavonoid oxidation potentials based on spin populations, the differences in the net atomic charges between a cation and a neutral flavonoid, between a radical and an anion of a flavonoid, and between a radical and a neutral flavonoid on a larger set of flavonoids (N = 35). By including six new flavonoids (5,6,7-trihydroxyflavone, 3,3',4',7-tetrahydroxyflavone, 3,7-dihydroxyflavone, 4',7-dihydroxyflavone, 4',5,7-trihydroxyisoflavone, and 6-hydroxyflavone), we created a respectable calibration set of 35 flavonoids with their oxidation potentials all measured at the same conditions by the same experimentalist. The best model was based on the mean values of the three variables using differences in the net atomic charges (R 2 = 0.970, S.E. = 0.043), which are connected with the three different mechanisms of electrochemical oxidation, SET-PT, SPLET, and HAT.

U ovom radu testirao sam naše kvadratne regresijske modele za procjenu oksidacijskih potencijala flavonoida, temeljene na spinskim populacijama, razlici atomskih naboja u kationu i neutralnoj formi flavonoida, radikala i aniona te između radikala i neutralnog flavonoida, na većem skupu flavonoida (N = 35). Uključenjem šest novih flavonoida (5,6,7-trihidroksiflavon,3,3’,4’,7-tetrahidroksiflavon, 3,7-dihidroksiflavon, 4’,7-dihidroksiflavon, 4’,5,7-trihidroksiizoflavon i 6-hidroksiflavon) stvorili smo respektabilan skup od 35 flavonoida s oksidacijskim potencijalima mjerenima od strane istog eksperimentalista pri istim uvjetima. Najbolji model temeljen je na srednjim vrijednostima triju varijabli koje su izvedene iz razlika atomskih naboja, a koje su povezane s tri moguća mehanizma elektrokemijske oksidacije flavonoida: SET-PT, SPLET i HAT.

Keywords: PM6; QSPR; atomic charges; atomski naboji; electrochemical oxidation; elektrokemijska oksidacija; polifenoli; polyphenols.

MeSH terms

  • Flavonoids*
  • Oxidation-Reduction

Substances

  • Flavonoids