Oligosaharidi iz sekundarnih biljnih sirovina - izdvajanje, karakterizacija i primjena u razvoju funkcionalnih konditorskih proizvod

doctoral thesis

• Title (english): Oligosaccharides from secondary raw materials of plant origin- isolation, characterization and implementation in the development of functional confectionery products
• Author: Aleksandra Vojvodić Cebin
• Mentor: Draženka Komes (mentor)
• Committee member: Božidar Šantek (predsjednik povjerenstva)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Chemistry and Technology of Carbohydrates and Confectionery Products); Zagreb
• Defense date and country: 2019-05-07, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology
• Universal decimal classification (UDC): 633/635 - Horticulture. Fruit growing. Viticulture. Gardening

Abstract

Cilj ovoga rada bio je istražiti mogućnost valorizacije odabranih sekundarnih biljnih sirovina: pulpe šećerne repe (SBP), ljuske oraha (WS), ljuske kakaovog zrna (CBH), ljuske crvenog luka (OP) i mahune graška (PP) kao izvora funkcionalnih komponenata - polisaharida i polifenola. Optimizacijom postupka izdvajanja postignuti su zadovoljavajući prinosi pročišćenih frakcija ksilana iz WS i PP (delignifikacijom i alkalnom ekstrakcijom) te pektina iz SBP, CBH (kiselinskom ekstrakcijom) i OP (ekstrakcijom s kelirajućim sredstvom), čijom su daljnjom parcijalnom enzimskom hidrolizom proizvedeni ksilooligosaharidi (XOS) i pektinski oligosahardi (POS) - oligogalakturonidi. Primjenom optimiranih uvjeta izdvajanja i enzimske hidrolize endo-ksilanazom ostvareno je visoko iskorištenje XOS iz WS i PP od približno 70 % i 79 % početnog udjela ksilana u sirovinama, u obliku ksilobioze i ksiloze (70:30). Primjenom endo-poligalakturonaze, najviša konverzija galakturonana iz OP iznosila je 41-45 % početnog udjela galakturonana u sirovini (od čega dominantno monomera (~30-50 %) i dimera (~35-40 %)), a iz CBH tek 7-8,5 % (od čega ~35-52 % monomera te di-, tri- i tetramera u podjednakom omjeru ostatka). Primjenom enzimskog koktela Viscozyme, 21-37,5 % početnog udjela galakturonana u SBP hidrolizirano je u oligogalakturonide (gotovo isključivo u monomer (približno 60-70 %) i tetramer). Osim polisaharida i oligosaharida, neizravno su izdvojeni i drugi sastojci dodane vrijednosti - polifenolni spojevi, otopljeni lignin i pročišćena celuloza, što otvara mogućnost potpune biorafinerije istraživanih sekundarnih biljnih sirovina i sličnih materijala, kao važnog aspekta održivog razvoja prehrambene industrije.

Abstract (english)

The aim of this thesis was to look into the possibilities of valorizing selected secondary raw materials of plant origin: sugar beet pulp (SBP), walnut shell (WS), cocoa bean husk (CBH), onion peel (OP) and pea pod (PP) as sources of functional components - polysaccharides and polyphenols. Upon optimization of recovery procedures, satisfactory yields of purified fractions of xylan from WS and PP (by delignification and alkaline extraction) and pectin from SBP, CBH (by diluted acid extraction) and OP (by chelator-mediated extraction) were obtained. Partial enzymatic hydrolysis of the recovered polysaccharides resulted in xylooligosaccharides (XOS) and pectic oligosaccharides (POS) - oligogalacturonides. At optimal conditions of isolation and hydrolysis using endo-xylanase, a high yield of XOS from WS and PP was obtained, approximately 70 % and 79 %, respectively, in a form of xylobiose and xylose (70:30). Using endo-polygalacturonase, maximal conversion of galacturonan from OP exhibited 41-45 % of the inital galacturonan content in OP (dominating in monomer (~30-40 %) and dimer (~35-40 %)), while from CBH only 7-8,5 % (with ~30-50 % of monomer, di-, tri- and tetramer at equal proportions of the rest). Using enzymatic cocktail Viscozyme, 21-37,5 % of the inital galacturonan content in SBP was hydrolysed into oligogalacturonides (almost exclusively monomer (60-70 %) and tetramer). Other value-added components along with polysaccharides and oligosaccharides were indirectly recovered, comprising polyphenols, solvatized lignin and purified cellulose, thus opening the possibility of complete birefinery of selected secondary plant raw materials and related substrates as an important aspect of sustainable development of the food industry.

• Keywords: enzimska hidroliza; ksilooligosaharidi; ljuska crvenog luka; ljuska kakaovog zrna; ljuska oraha; mahuna graška; pektinski oligosaharidi; PMP derivatizacija; prebiotici; pulpa šećerne repe
• Keywords (english): Enzymatic hydrolysis; xylooligosacchrides; onion peel; cocoa bean husk; walnut shell; pea pod; pectic oligosaccharides; PMP derivatization; prebiotics; sugar beet pulp
• Language: croatian
• URN:NBN: urn:nbn:hr:159:709645
• Promotion: 2021-05-07
• 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
• Extent: 310 str. : 30 cm
• File origin: Born digital
• Access conditions: Open access
• Created on: 2021-01-28 11:09:53