N. Hudz^1,2*, V. Turkina³, O. Yezerska¹, L. Kobylinska⁴, A. Filipska¹,
J. Karosienė⁵, D. Galinytė6, G. Balčiūnaitė–Murzienė⁷,
S. Khomyak⁸, N. Savickienė⁹

¹Department of Drug Technology and Biopharmacy,
Danylo Halytsky Lviv National Medical University, Lviv, Ukraine;
²Department of Pharmacy and Ecological Chemistry, University of Opole, Poland;
³Research Institute of Epidemiology and Hygiene,
Danylo Halytsky Lviv National Medical University, Lviv, Ukraine;
⁴Department of Biochemistry, Danylo Halytsky Lviv National Medical University, Lviv, Ukraine;
⁵Laboratory of Algology and Microbial Ecology, Nature Research Centre, Vilnius, Lithuania;
⁶Department of Pharmacognosy, Lithuanian University of Health Sciences, Kaunas, Lithuania;
⁷Institute of Pharmaceutical Technologies, Lithuanian University of Health Sciences, Kaunas, Lithuania;
⁸Department of Technology of Biologically Active Substances, Pharmacy and Biotechnology,
Lviv Polytechnic National University, Lviv, Ukraine;
⁹Department of Pharmacognosy, Lithuanian University of Health Sciences, Kaunas, Lithuania;
*e-mail: natali_gudz@ukr.net

Received: 09 October 2022; Revised: 14 November 2022;
Accepted: 16 November 2022; Available on-line: 19 December 2022

The physicochemical characteristics of phycocyanin extracted from cyanobacteria collected in Kaunas Lagoon were studied (spectrum characteristics, C-PC content in the dry mass and chemical purity). It was determined that the tested concentrations of C-PC in purified water should be in the range of 0.02–0.16% for measuring C-PC content in the dry mass and its spectrum characteristics. The two clear absorption maxima were detected in the spectrum of C-PC at the wavelengths of 277 and 619 nm. The content of C-PC in the dry powder form was in the range of 7.25% to 9.30% depending on its concentration in the solution and type of spectrophotometer. Furthermore, a purity factor of 1.5 was calculated, which indicated the food qualification of the obtained biomass of C-PC. Finally, the analytical procedure for studying the pro- and anti-oxidant activity of C-PC was developed and the antioxidant activity of C-PC was measured for the available markers. It was revealed that C-PC has dual properties (pro- and anti-oxidant ones) depending on its concentration, more exactly, its content in reaction mixtures with 2,2-diphenyl-1-picrylhydrazyl (DPPH). The following issues were resolved during the research: the concentration of ethanol in the DPPH solution was chosen in order to avoid precipitation of proteins in the reaction mixtures (50%); the ratio of the solution of C-PC to the DPPH solution was selected; the selected concentrations of the markers for the construction of their calibration curves were chosen for quercetin and for rutin. The antioxidant activity of the obtained C-PC sample was determined.

Keywords: antioxidant activity, C-phycocyanin, cyanobacteria, DPPH, quercetin, rutin