EVALUATION OF THE CYTOTOXICITY OF ZINC CHITOSAN BIONANOCOMPOSITES FOR BIOMEDICAL APPLICATIONS

Universitatea de Stat de Medicină şi Farmacie „Nicolae Testemiţanu”, Chişinău, Republica MoldovaIntroducere. Bionanocompozitele chitosan zinc prezintă interes pentru utilizarea în domeniile biomedicale datorită proprietăților multifuncționale care le fac ca candidați perfecți pentru a fi aplicate în diagnostic, terapia medicamentoasă, agenți anticancer și antibacterieni. Pentru utilizarea și implementarea în siguranță un parametru important este evaluarea influenței asupra culturilor celulare. Scopul lucrării constă în evaluarea citotoxicității bionanocompozitelor chitosan zinc asupra culturii Rhodosporidium toruloides CNMN-Y-30. Material și metode.În cadrul experiențelor prezentate în acest studiu au fost utilizate nanoparticule ZnO <50 nm și chitosan (Sigma Aldrich). Suspensiile au fost realizate prin metoda sonochimică cu volumul NPs de 2% și 5% și au fost adăugate la etapa inoculării în concentrații de 30, 50 și 70 mg/L. Efectul a fost testat pe cultura standartizată Rhodosporidium toruloides CNMN-Y-30. Rezultate Analiza acțiunii bionanocompozitelor chitosan-zinc în volum de 2% indică valori maxime ale viabilității celulare după 6 și 24 ore în toate concentrațiile studiate. S-a stabilit că viabilitatea celulară crește cu 20-27%, comparativ cu varianta martor. Totodată, studiul comparativ a acțiunii bionanocompozitului aplicat în volum de 5% manifestă o citotoxicitate ridicată asupra viabilității și morfologiei celulare. În variantele experimentale în care au fost aplicate concentrațiile de 30-50 mg/L viabilitatea a scăzut cu până la 78%. Efectul a fost mai evident la contactul celulelor cu concentrația de 70 mg/L rezultatele indică o reducere a viabilității celulare cu 90% și revărsarea conținutului celular ca urmare a deteriorării peretelui și membranei celulare. Concluzii. Studiul realizat a demonstrat că testele de viabilitate și morfologie celulară sunt indici importanți în procesul de evaluare a acțiunii bionananocompozitelor obținute prin diferite procedee.Background. Chitosan-zinc bionanocomposites are of interest for use in biomedical fields due to their multifunctional properties that make them perfect candidates to be applied in diagnostics, drug therapy, anticancer and antibacterial agents. An important parameter for safe use and implementation is the evaluation of the influence on cell cultures. Objective of the study. The aim of the work is to evaluate the cytotoxicity of zinc chitosan bionanocomposites on Rhodosporidium toruloides CNMN-Y-30 culture. Material and methods. ZnO <50 nm nanoparticles and chitosan (Sigma Aldrich) were used in the experiments presented in this study. Suspensions were made by the sonochemical method with NPs volumes of 2% and 5% and were added at the inoculation step in concentrations of 30, 50 and 70 mg/L. The effect was tested on the standard culture Rhodosporidium toruloides CNMN-Y-30. Results. Analysis of the action of chitosan-zinc bionanocomposites in 2% volume indicates maximum values of cell viability after 6 and 24 hours in all studied concentrations. Cell viability was determined to increase by 20-27% compared to the control variant. At the same time, the comparative study of the action of the bionanocomposite applied in 5% volume shows a high cytotoxicity on cell viability and morphology. In the experimental variants where 30-50 mg/L concentrations were applied, the viability decreased by up to 78%. The effect was more obvious when the cells were contacted with the concentration of 70 mg/L, the results indicate a reduction of cell viability by 90% and the overflow of cell contents as a result of damage to the cell wall and membrane. Conclusion. The study demonstrated that cell viability and morphology tests are important indices in evaluating the action of bionanocomposites obtained by different processes

Evaluation of the biochemical composition and antioxidant activity of preparation based on pigments extracted from the remaining biomass of <i>Arthrospira platensis</i>

Biotechnological research is currently focused on obtaining preparations based on natural pigments due to their properties and positive impact on human and animal health. Thus, this study aimed to evaluate the biochemical composition and antioxidant activity of the preparation based on pigments obtained from the remaining biomass of Arthrospira platensis. The obtained results established that the preparation is characterized by a high content of β-carotene, lutein, chlorophyll pigments, and sulfated polysaccharides. Due to its composition, the preparation also possesses high antioxidant activity and the catalase and superoxide dismutase enzymes. These findings highlight the high biological value of the new preparation and the enormous potential for implementation in medicine, the animal husbandry sector, and the food and cosmetic industry

Effect of Fe3O4 and TiO2 Nanoparticles on Catalase Activity and β-Carotene Content at Pigmented Yeast Strain Rhodotorula gracilis

The properties of nanoparticles have been used in a wide range of potential applications in food industry, medicine, microbial biotechnology, cosmetics, environmental production. Research results of evaluation of the effect of Fe3O4 and TiO2 nanoparticles applicated in large concentration limits on some parameters of pigmented yeast strain Rhodotorula gracilis CNMN-Y-30 are presented in this paper. It was established that nanoparticles selected for study caused toxic effects on β-caroten accumulation and activity of antioxidant enzyme catalase depending on concentration and nanostructure. The strong correlation between concentration of nanoparticles and evaluated components has been revealed at studied yeast strain. Coefficients of correlation varied in limits R2 = 0.623... 0.951. For the first time, the determination of β-carotene accumulation and catalase activity rate as functional tests for estimation of toxicity of nanoparticles for pigmented yeast strain Rhodotorula gracilis was effectuated. Thus, it was established that adaptive response of yeast strain to the presence of Fe3O4 and TiO2 nanoparticles has been manifested by modification of the processes of β-carotene biosythesis and catalase activity