Ispitivanje antioksidacijske aktivnosti probiotičkih bakterija iz jagode (Fragaria ananassa × Duch.) u kombinaciji s ekstraktom maginje (Arbutus unedo L.)

master's thesis

• Title (english): Antioxidant activity evaluation of probiotic bacteria from strawberry (Fragaria ananassa × Duch.) in combination with strawberry tree fruit extract (Arbutus unedo L.)
• Author: Filip Dolenec
• Mentor: Danijela Bursać Kovačević (mentor)
• Mentor: Deni Kostelac (pomoć pri izradi, neposredni voditelj)
• Mentor: Anica Bebek Markovinović (pomoć pri izradi, neposredni voditelj)
• Committee member: Ksenija Markov (predsjednik povjerenstva)
• Committee member: Predrag Putnik (član povjerenstva)
• Committee member: Jasna Mrvčić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Technology of Fruits and Vegetables Preservation and Processing); Zagreb
• Defense date and country: 2023-09-26, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Nutrition

Abstract

Primjenom probiotičkih bakterija izoliranih iz voća u fermentaciji voćnih ekstrakata nastoji se razviti inovativne funkcionalne proizvode koji bi svojim izgledom, okusom te biološkom vrijednošću bili privlačniji potrošačima, a pritom osigurali dobrobit za njihovo zdravlje. U ovome radu provedena je probiotička karakterizacija dvaju sojeva bakterija mliječne kiseline izoliranih iz ploda jagode (Fragaria ananassa × Duch.) sorte 'Albion'. Na temelju visokog preživljavanja u simuliranim uvjetima gastrointestinalnog sustava i visoke sposobnosti formacije biofilmova, soj Lactiplantibacillus plantarum DB2 odabran je za fermentaciju vodenog ekstrakta maginje (Arbutus unedo L.), koji je potom mikroinkapsuliran i liofiliziran s ciljem produljenja trajnosti i očuvanja funkcionalnih svojstava. Oba ispitivana soja pokazala su se sigurnim za upotrebu. Fermentacija vodenog ekstrakta maginje je uspješno provedena pri čemu je zadržana antioksidacijska aktivnost dobivenog fermenta (80 %). Nakon mikroinkapsulacije i liofilizacije održano je oko 50 % antioksidacijske aktivnosti u slučaju nefermentiranog ekstrakta te oko 20 % u slučaju fermentiranog ekstrakta.

Abstract (english)

The use of probiotic bacteria isolated from fruits in fermentation of fruit extracts attempts to develop innovative functional products that are attractive to consumers due to their appearance, taste and biological value, while providing health benefits. In this work, probiotic characterization of two strains of lactic acid bacteria from strawberry (Fragaria ananassa × Duch.) cultivar 'Albion' was performed. Due to its high survival rate under simulated gastrointestinal conditions and high ability to form biofilms, strain Lactiplantibacillus plantarum DB2 was selected for fermentation of strawberry tree fruit (Arbutus unedo L.) water extract, which was microencapsulated and freeze-dried to extend shelf life and preserve functional properties. Both strains were found to be safe. Fermentation of strawberry tree fruit water extract was successfully performed, while antioxidant activity of obtained ferment was maintained (80 %). Microencapsulated and freeze-dried extracts of strawberry tree fruit showed significant antioxidant activity, 50 % for unfermented and 20 % for fermented extract.

• Keywords: fermentacija; probiotici; jagoda; maginja; liofilizacija
• Keywords (english): fermentation; probiotics; strawberry; strawberry tree fruit; freeze-drying
• Language: croatian
• URN:NBN: urn:nbn:hr:159:438723
• Study programme: Title: Nutrition; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra nutricionizma (magistar/magistra nutricionizma)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-06-06 09:45:21