In vitro bioraspoloživost polifenola komine masline

master's thesis

• Title (english): In vitro bioavailability of olive pomace polyphenols
• Author: Marija Srbić
• Mentor: Dubravka Vitali Čepo (mentor)
• Committee member: Dubravka Vitali Čepo (predsjednik povjerenstva)
• Committee member: Lovorka Vujić (član povjerenstva)
• Committee member: Marija Grdić Rajković (član povjerenstva)
• Granter: University of Zagreb; Faculty of Pharmacy and Biochemistry; (Department of food chemistry); Zagreb
• Defense date and country: 2018-05-25, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Pharmacy; Pharmacy

Abstract

Ekstrakt komine masline sadrži različite biološki aktivne polifenole s brojnim blagotvornim učincima na
zdravlje. No, da bi mogli postići ikakve zdravstvene učinke, bioaktivni spojevi moraju biti bioraspoloživi, a
bioraspoloživost ovisi o biološkoj dostupnosti (oslobađanju iz matriksa hrane tijekom gastrointestinalne
digestije) te o dijalizibilnosti (apsorpciji u crijevima). Ciljevi ovog rada bili su odrediti in vitro
gastrointestinalnu stabilnost, biološku dostupnost te dijalizibilnost polifenola određivanjem koncentracije
hidroksitirosola i tirosola pomoću tekućinske kromatografije visoke djelotovornosti spregnute s
flourescencijskim detektorom. Uzorci su bili ekstrakt komine masline bez ekscipijensa (nativni ekstrakt) i
ekstrakti komine masline sa sljedećim ekscipijensima: beta ciklodekstrinom (B), nasumično metiliranim
beta CD-om, (G), hidroksipropil beta CD-om (HPB) i gama CD-om (G). Zaključeno je da svi uzorci
pokazuju relativno visoku gastričnu stabilnost (od 72 do 108%) i biološku dostupnost (od 66 do 101%)
fenolne frakcije. Najveća dijalizibilnost u smislu sadržaja hidroksitirosola i tirosola je postignuta kada je
kao ekscipijens u pripremi ekstrakata korišten hidroksipropil –beta-ciklodekstrin u koncentraciji 16 mg/mL.

Abstract (english)

Olive pomace extracts (OPE) contain various biologically active polyphenols (PPs) with numerous health
benefits. However, to exert any beneficial effects, bioactive compounds should be bioavailable, and their
bioavailability depends on their release from the matrix during the gastro-intestinal (GI) digestion
(bioaccessibility) and later intestinal absorption (dialisibility). The aims of this research were to determine
in vitro GI stability, bioaccessibility and dialysability of PPs in terms of concentration of hydroxytyrosol
(HTS) and tyrosol (TS) which were obtained by HPLC-FLD method. Samples were OPE prepared without
excipient (native extract, NE), and with following excipients: beta-CD (B), randomly methylated beta-CD
(RAMEB), hydroxypropyl beta-CD (HPB), and gamma-CD (G). The in vitro GI digestion consisted of two
sequential steps; an initial pepsin/HCl digestion to simulate gastric conditions, followed by a digestion with
bile salts/pancreatin and dialysis tubing, to simulate duodenal digestion and absorption by passive diffusion.
It is concluded that all samples have relatively high gastric stability (72-108%) and bioaccessibility (66-
101%). The highest dialysability (%) in terms of HTS and TS content was obtained for HPB (16 mg/mL)
sample.

• Keywords: stabilnost; biološka dostupnost; dijalizibilnost; in vitro gastrointestinalna digestija; HPLC
• Keywords (english): stability; bioaccessibility; dialysability; in vitro gastrointestinal digestion; HPLC
• Language: croatian
• URN:NBN: urn:nbn:hr:163:930928
• Study programme: Title: Pharmacy; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: magistar/magistra farmacije (magistar/magistra farmacije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-01-16 08:26:08