Assessment of the synergistic effects of bioactive compounds mixtures by determining their in vitro antioxidant

Posljednjih godina, ispitivanje bioaktivnih spojeva s antioksidacijskim svojstvima omogućuje optimizaciju njihovih svojstava i formulaciju novih funkcionalnih svojstava u svrhu prevencije i liječenja različitih bolesti. U ovom radu provedeno je određivanje antioksidacijskih svojstava pojedinačnih i kombinacije bioaktivnih spojeva kvercetina, askorbinske kiseline i aminokiselina lizina i karnitina kako bi se utvrdilo njihovo sinergističko međudjelovanje te učinak inkapsulacije njihove formulirane mješavine u alginatne i etil-celulozne čestice. U tu svrhu primijenjene su in vitro metode određivanja antioksidacijskog kapaciteta putem „gašenja“ slobodnih radikala (ABTS i DPPH metode) te metoda na modelnim staničnim linijama karcinoma grkljana (HEp2) i debelog crijeva (CaCo2). Dobiveni rezultati pokazali su da se formuliranjem mješavina kvercetina i askorbinske kiseline u kombinaciji s aminokiselinama lizinom i karnitinom u vodenim otopinama postiže sinergistički učinak na povećanje antioksidacijskog kapaciteta mješavina. Mješavina navedenih spojeva pokazuje citoprotektivno i antioksidacijsko djelovanje na HEp2 stanice, što se pripisuje jednakom djelovanju kvercetina i askorbinske kiseline dok pojedinačne aminokiseline lizin i karnitin ne pokazuju nikakvo djelovanje na HEp2 i CaCo2 stanice. Inkapsulacija navedene mješavine učinkovitija je u slučaju formuliranja alginatnih čestica primjenom ionskog geliranja, no za postizanje izraženijih bioloških učinaka potrebna je daljnja optimizacija inkapsuliranih sustava. During recent years, evaluation of bioactive compounds with antioxidant properties enables the optimization of their properties and formulation of new functional properties aiming at their use in prevention and treatment of different health issues. In this study, antioxidant properties of single and the combination of bioactive compounds quercetin, ascorbic acid, aminoacids lysine and carnitine was assessed to evaluate their synergistic interactions and effects, as well as the potential of their encapsulation in alginate and ethyl-cellulose particles. For that purpose, in vitro methods of antioxidant capacity determination by free radical scavenging assays (ABTS and DPHH assays) and methods on model human laryngeal carcinoma (HEp2) and (CaCo2) cell lines were employed. The obtained results indicated that by formulating mixtures of quercetin, ascorbic acid in combination with aminoacids lysine and carnitine in water solutions synergistic effect on the enhancement of antioxidant capacity is achieved. The formulated mixture exhibits cytoprotective and antioxidant activity on HEp2 cells, which is attributed to the same effect of quercetin and ascorbic acid, while single aminoacids lysine and carnitine have no effect on HEp2 and CaCo2 cells. Encapsulation of formulated mixture is more efficient in case of alginate particles obtained by ionic gelation, but for achieving more pronounced biological effects further optimization of encapsulated delivery systems is required.