Volume: 5, 2026
5th International PhD Students’ Conference at the University of Life Sciences in Lublin, Poland:
ENVIRONMENT – PLANT – ANIMAL – PRODUCT
Abstract number: H005
DOI: https://doi.org/10.24326/ICDSUPL5.H005
Published online: 22 April 2026
Antioxidant activity of microencapsulated seed protein hydrolysates from selected plants of the Cucurbitaceae family
Magdalena Borecka*, Kinga Łubińska and Monika Karaś
Department of Food Biochemistry and Food Chemistry, University of Life Sciences in Lublin, 8 Skromna St., 20-704 Lublin, Poland
* Corresponding author: magdalena.borecka@up.edu.pl
Plant-derived bioactive peptides represent a promising group of natural compounds with antioxidant potential, which may support the prevention of diseases associated with oxidative stress. Particular attention has been given to seed proteins from plants of the Cucurbitaceae family, such as watermelon (A), pattypan squash (P), and zucchini (K), which may serve as a source of highly bioactive peptides after enzymatic hydrolysis. This study aimed to evaluate the antioxidant properties of microencapsulated protein hydrolysates obtained from seeds of selected Cucurbitaceae species. Protein isolates were prepared from defatted seed flours and subsequently subjected to enzymatic hydrolysis using pepsin (p), trypsin (t), and their sequential action (p+t). The obtained hydrolysates were microencapsulated by freeze-drying with maltodextrin as a carrier. The resulting microcapsules were analyzed for peptide and protein content, as well as antioxidant activity using ABTS, DPPH, Fe²⁺ chelation, and reducing power assays. The highest peptide content was observed for sample Ap+t (1.454 mg/mL), indicating a beneficial effect of sequential enzyme treatment on the degree of protein hydrolysis. The highest ABTS radical scavenging activity was also recorded for sample Ap+t at 20 mg/mL (45.08%), whereas the highest DPPH radical scavenging activity was found for sample Ap (49.55%). The greatest Fe²⁺ chelating ability was obtained for sample Pt (47.12%), while the highest reducing power was observed for sample Ap (A700 = 0.227). The obtained results indicate that both the type of enzyme used and the plant species significantly influence the antioxidant properties of the microcapsules, confirming their potential application in functional foods and nutraceuticals.
Keywords: antioxidant activity; bioactive peptides; Cucurbitaceae seeds; functional food; microencapsulation
How to cite
Borecka M., Łubińska K., Karaś M., 2026. Antioxidant activity of microencapsulated seed protein hydrolysates from selected plants of the Cucurbitaceae family. In: 5th International PhD Students’ Conference at the University of Life Sciences in Lublin, Poland: Environment – Plant – Animal – Product. https://doi.org/10.24326/ICDSUPL5.H005