Possibilities of olive pomace extract application in bigenic synthesis of selenium nanoparticles

Selen je esencijalni mikronutrijent i u organizmu je sastavni dio selenoproteina važnih za obranu od oksidacijskog stresa. Najbolji omjer učinkovitosti i sigurnosti ima nanoselen, kojeg je prilikom sinteze potrebno stabilizirati oblaganjem. U ovom radu je istraživana mogućnost primjene ekstrakta komine masline (EKM) kao sredstva za oblaganje u sintezi nanoselena. EKM je korišten u masenim udjelima od 0,3 % i 0,6 %, a karakteristike dobivenih nanočestica uspoređene su s onima dobivenim standardnim postupkom kemijske sinteze. Nanočesticama selena određena je raspodjela veličine čestica, zeta potencijal te je istražena njihova antiradikalna (ORAC i TEAC metoda) i reduktivna učinkovitost (Folin-Ciocalteu metoda). Dobiveni rezultati pokazali su da primjena EKM u biogenoj sintezi, u koncentraciji od 0,3 %, rezultira raspodjelom veličine čestica u rasponu od 100 nm – 200 nm, što je slično veličini čestica dobivenim standardnim postupkom kemijske sinteze. Povećanje udjela EKM značajno je povećalo srednji promjer čestica i širinu raspodjele veličina čestica. Zeta potencijal biogeno sintetiziranih nanočestica (-34 mV) pokazao je značajno veće apsolutne vrijednosti u odnosu na kemijske (-17,2 mV), iz čega je moguće pretpostaviti da, za razliku od polivinilpirolidona korištenog u kemijskoj sintezi, EKM stabilizira nastale nanočestice primarno putem elektrostatskih interakcija. Za razliku od kemijski sintetiziranih nanočestica, biogeno sintetizirane nanočestice pokazuju značajnu antiradikalnu (TEAC, ORAC) i reduktivnu (Folin Ciocalteu) učinkovitost (redom: 125 mg TE/L; 251 mg TE/L i 200 mg GAE/L).Selenium is an essential micronutrient and as an integral part of selenoproteins in the body it is essential for defense against oxidative stress. Nanoselenium has the best efficiency/safety ratio, but due to its tendency to agglomerate, it needs to be stabilized by coating during synthesis. In this paper, we investigated the possibility of using olive pomace extract (OPE) as a coating agent in the synthesis of nanoselenium. OPE was used at two concentration levels, 0.3 % and 0.6 %, and the characteristics of the obtained nanoparticles were compared with those obtained by a standard chemical synthesis. The characterization of obtained nanoparticles included determination of particle size distribution, zeta potential, antiradical (ORAC and TEAC method) and reductive capacity (Folin-Ciocalteu method). Obtained results showed that the application of 0.3 % OPE in biogenic synthesis of nanoselenium results in a particle size distribution between 100 nm - 200 nm, which is similar to the particle size obtained by the standard chemical synthesis process. The increase of OPE concentration in reaction mixture significantly increased the mean particle diameter and the range of the particle size distribution. Zeta potential of biologically synthesized nanoparticles showed significantly higher absolute values (-34 mV) compared to chemical nanoselenium (-17.2 mV). Based on obtained data, it can be assumed that, unlike polyvinylpyrrolidone used in chemical synthesis, OPE stabilizes the nanoparticles primarily by electrostatic interactions. Unlike chemically synthesized nanoparticles, biologically synthesized nanoselenium showed significant antiradical (TEAC, ORAC) and reductive (Folin-Ciocalteu) efficacy (125 mg TE/L; 281 mg TE/L and 200 mg GAE/L, respectively)