Optimiranje ultrazvukom potpomognute ekstrakcije polifenolnih spojeva iz lista crnog ribiza (Ribes nigrum L.)

master's thesis

• Title (english): Optimization of ultrasound assisted extraction of polyphenol compounds from blackcurrant leaves (Ribes nigrum L.)
• Author: Iva Didović
• Mentor: Verica Dragović Uzelac (mentor)
• Mentor: Erika Dobroslavić (pomoć pri izradi, neposredni voditelj)
• Committee member: Maja Repajić (predsjednik povjerenstva)
• Committee member: Ivona Elez Garofulić (član povjerenstva)
• Committee member: Sandra Balbino (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: 2024-09-26, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Listovi crnog ribiza bogati su polifenolima, bioaktivnim spojevima koji se iz biljnog materijala mogu izolirati različitim tehnikama ekstrakcije. Cilj ovog rada bio je definirati optimalne uvjete izolacije fenolnih spojeva iz lista crnog ribiza primjenom ultrazvučne ekstrakcije koristeći 30 %-tnu vodenu otopinu etanola kao ekstrakcijsko otapalo. Utvrđivani su utjecaji amplitude (50, 75, 100 %) te trajanja ekstrakcije (5, 10 min) na maseni udio ukupnh fenolnih spojeva i antioksidacijski kapacitet (ABTS, FRAP, DPPH) ekstrakata lista crnog ribiza. Uvjeti ekstrakcije značajno su utjecali na maseni udio fenolnih spojeva i antioksidacijski kapacitet ekstrakata pri čemu je udio fenola varirao od 17,03 do 38,09 mg GAE g⁻¹, a antioksidacijski kapacitet od 146,88 do 487,34 μmol TE g⁻¹ (FRAP), 165,89 - 348,27 μmol TE g⁻¹ (DPPH), 188,35 - 455,47 μmol TE g⁻¹ (ABTS). Optimalni uvjeti pri kojima su određeni najviši udjeli fenolnih spojeva bili su: omjer otapalo:uzorak 40:1, amplituda 100 % te vrijeme ekstrakcije 10 min.

Abstract (english)

Blackcurrant leaves are rich in polyphenols, bioactive compounds that can be isolated from plant material by various extraction tehniques. The aim of this work was to define the optimal conditions for the isolation of phenolic compounds from blackcurrant leaves using ultrasonic extraction using a 30% aqueous ethanol solution as an extraction solvent. The influence of amplitude (50, 75 and 100 %) and duration of extraction (5 and 10 min) on the mass fraction of total phenolic compounds and antioxidant capacity (ABTS, FRAP, DPPH) of blackcurrant leaf extracts was determined. The extraction conditions significantly influenced the mass fraction of phenolic compounds and the antioxidant capacity of the extracts with the phenol fraction varying from 17,03 - 38,09 mg GAE g⁻¹ and the antioxidant capacity from 146.88 do 487.34 μmol TE g⁻¹ (FRAP), 165.89 – 348.27 μmol TE g⁻¹ (DPPH), 188.35 – 455.47 mol TE g⁻¹ (ABTS). The optimal conditions under which the highest proportions of phenolic compounds were determined were: solvent:sample ratio 40:1, amplitude 100 % and extraction time 10 min.

• Keywords: list crnog ribiza; ekstrakcija potpomognuta ultrazvukom; polifenolni spojevi; antioksidacijski kapacitet
• Keywords (english): black currant leaf; ultrasound-assisted extraction; polyphenolic compounds; antioxidant capacity
• Language: croatian
• URN:NBN: urn:nbn:hr:159:260133
• Study programme: Title: Food Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka prehrambenog inženjerstva (magistar/magistra inženjer/inženjerka prehrambenog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-10-16 09:47:10