Ultrazvukom potpomognuta ekstrakcija biološki aktivnih sastojaka iz taloga crnih vina

doctoral thesis

• Title (english): Ultrasound assisted extraction of bioactive compounds from red wine lees
• Author: Filip Dujmić
• Mentor: Mladen Brnčić (mentor)
• Committee member: Karin Kovačević-Ganić (predsjednik povjerenstva)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; Zagreb
• Defense date and country: 2015-07-10, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology
• Universal decimal classification (UDC): 663 - Industrial microbiology. Industrial mycology. Zymurgy, fermentation industry. Beverage industry. Stimulant industry

Abstract

U ovom radu istražen je utjecaj ultrazvukom potpomognute ekstrakcije (UPE) bioaktivnih spojeva iz taloga crnih vina sorti Merlot i Vranac u odnosu na klasičnu ekstrakciju. Ispitan je utjecaj vremena ekstrakcije (120 s, 322.10 s, 810 s, 1297.90 s i 1500 s), primijenjene amplitude ultrazvučnog procesora snage 400W (30 %, 38.78 %, 60 %, 81.21 % i 90 %) i promjera sondi od 7 mm, 22 mm i 40 mm na sastav i količinu bioaktivnih spojeva u dobivenim ekstraktima. Polifenolni profil ekstrakata taloga određen je spektrofotometrijskim metodama i tekućinskom kromatografijom visoke djelotvornosti (HPLC). Spektrofotometrijske metode korištene su za određivanje antioksidacijske aktivnost (DPPH i FRAP metoda), ukupnih fenola i monomernih antocijana, a količina i vrsta fenolnih spojeva (flavonoli, flavanoli, fenolne kiseline, stilbeni, antocijani) određena je HPLC metodom. Primjenom računalnog programa Design Expert 9.0.4.1., proveden je postupak optimizacije procesa ultrazvukom potpomognute ekstrakcije (UPE) polifenolnih spojeva iz vinskih taloga, baziran na prinosu ekstrakcije. Optimalni uvjeti ekstrakcije definirani su maksimiziranjem vrijednosti najznačajnih istraživanih fenolnih spojeva. Najbolji ekstrakcijski kapacitet postignut je primjenom ultrazvučne sonde promjera 22 mm, primijenjenom amplitudom ultrazvučnog procesora od 90 % pri vremenu ekstrakcije u trajanju od 1500 sekundi. Ekstrakcija potpomognuta ultrazvukom se pokazala značajno učinkovitijom, jer se ekstrakcijski kapacitet svih istraživanih bioaktivnih spojeva povećao od 5 % do 120 %, a vrijeme ekstrakcije je skraćeno za 2,5 puta u odnosu na klasičnu ekstrakciju. Rezultati dobiveni za antioksidacijski potencijal korištenjem UPE pokazuju povećanje od 10.49 % do 75.53% (DPPH) i 20.27% do 114.34% (FRAP) u usporedbi s konvencionalnom metodom ekstrakcijom.

Abstract (english)

In this thesis influence of process parameters of ultrasonically assisted extraction (UAE) of bioactive compounds from Vranac and Merlot cultivars was investigated and compared to conventional extraction. Effect of extraction time (120 s, 322.10 s, 810 s, 1297.90 s and 1500 s), applied amplitude of 400 W ultrasonic processor (30 %, 38.79 %, 60 %, 81.21 % and 90 %) and probe diameters (7 mm, 22 mm and 40 mm) on quantity and composition of bioactive compounds in obtained extracts was investigated. Polyphenolic profiles of wine lees extracts were determined using spectrophotometric methods and high-performance liquid chromatography (HPLC). Spectrophotometric methods were used for determination of antioxidative activity (DPPH and FRAP methods), total phenolic content, as well as monomer anthocyanins, while individual phenolic compounds (flavonols, flavanols, phenolic acids, stilbenes, and anthocyanins) were determined and identified using HPLC. Using Design Expert 9.0.4.1. software, optimization of UAE process was conducted based on the extraction yield of bioactive compounds. Optimal extraction conditions were calculated by maximizing of values of most important investigated polyphenolic compounds. Optimal extraction capacity is obtained using 22 mm ultrasonic probe in duration of 1500 s and 90 % of maximal amplitude. Compared to conventional extraction, UAE shows significant increase in extraction yield (5 % to 120 %) during up to 2.5 times shorter extraction process. In terms of extract’s antioxidative potential, UAE shows 10.49% to 75.53% (DPPH) and 20.27% to 114.34% (FRAP) increase as compared to conventional extraction.

• Keywords: vinski talog; parametri ekstrakcije; ultrazvuk; flavonoli; flavanoli; fenolne kiseline; stilbeni; antocijani; HPLC
• Keywords (english): wine lees; extraction parameters; ultrasound; flavanols; flavonols; phenolic acids; stilbenes; anthocyanins; HPLC
• Language: croatian
• URN:NBN: urn:nbn:hr:159:727833
• Promotion: 2015-09-27
• Study programme: Title: Food Technology; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti (doktor/doktorica znanosti)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2018-05-18 08:48:29