Izolacija bioaktivnih spojeva iz stevije (Stevia rebaudiana Bertoni) primjenom ubrzane ekstrakcije otapalima pri povišenom tlaku

master's thesis

• Title (english): Accelerated solvent extraction of bioactive compounds from stevia (Stevia rebaudiana Bertoni) leaves
• Author: Dragana Obradović
• Mentor: Danijela Bursać Kovačević (mentor)
• 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: 2016-12-21, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

U ovom radu ispitavana je učinkovitost ekstrakcije bioaktivnih spojeva iz lista stevije primjenom ubrzane ekstrakcije otapalima pri povišenom tlaku uz vodu kao otapalo. ASE ekstrakcija je provedena variranjem statičkog vremena ekstrakcije (5 i 10 minuta), temperature ekstrakcije (100 °C, 130 °C i 160 °C) te broja ciklusa ekstrakcije (1, 2 ili 3 ciklusa). U ekstraktima provedeno je spektrofotometrijsko određivanje ukupnih fenola, proantocijanidina, klorofila A i B. Na temelju dobivenih rezultata statističkom analizom određeni su optimalni parametri ASE ekstrakcije pri kojima se postižu najveći prinosi. Za ukupne fenole optimalni parametri bi bili 160°C, 5 min, 2 ciklusa, za proantocijanidine: 160°C, 10 min, 3 ciklusa, za klorofil A: 100°C, 10 min, 2 ciklusa te za klorofil B: 160°C, 10 min, 3 ciklusa.

Abstract (english)

The aim of this study was to investigate the extraction efficiency of bioactive compounds from stevia leaves by using accelerated solvent extraction with water as solvent. ASE extraction is carried out by varying the static extraction time (5 , 10 minutes), the extraction temperature (100 ° C , 130 ° C and 160 ° C ) and the number of extraction cycles ( 1 , 2 or 3 cycles ). The content of total phenols, proanthocyanidins, chlorophyll A and B were determined spectrophotometrically. The optimal parameters for ASE extraction were determined based on the results and statistical analysis. For total phenols optimal parameters were 160 ° C , 5 min , 2 cycles , for the proanthocyanidins : 160 ° C , 10 min , 3 cycles , for the chlorophyll A : 100 ° C , 10 min , 2 cycles and for chlorophyll B: 160 ° C , 10 min , 3 cycles.

• Keywords: list stevije; ASE; ukupni fenoli; proantocijanidini; klorofil A; klorofil B
• Keywords (english): stevia leaf; ASE; total phenols; proanthocyanidins; chlorophyll A and B
• Language: croatian
• URN:NBN: urn:nbn:hr:159:795900
• 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: 2017-04-24 09:17:03