diplomsko delo
Taja Majdič (Author), Drago Kočar (Mentor)

Abstract

Med je naravno živilo, ki ga proizvajajo čebele in nastane lahko iz različnih virov: iz cvetličnega nektarja ali drugih izločkov živih rastlinskih delov ali pa iz različnih vrst mane. Kemično je med kompleksna mešanica številnih organskih in anorganskih spojin, kot so sladkorji, beljakovine, aminokisline, encimi, vitamini, organske kisline, voda, minerali in polifenoli. V diplomski nalogi sem z uporabo spektrofotometrične analize in tekočinske kromatografije proučevala vsebnost fluorescentnih spojin v medu, tj. spojin, ki pri relaksaciji z vzbujenih stanj emitirajo fotone nižjih energij oz. oddajo svetlobo pri daljših valovnih dolžinah. Znano je, da med vsebuje številne fluorofore, npr. polifenole, vitamine in aminokisline. Analizirala sem 5 vrst medu različnega botaničnega porekla, po 3 vzorce vsake vrste, ki jih je bilo treba najprej ustrezno pripraviti. Uporabila sem HPLC z UV in fluorescenčno detekcijo in nato interpretirala rezultate. Z UV-detekcijo sem najmanj spojin, tako številčno kot z vidika koncentracije, zaznala pri akacijevem in kostanjevem medu, pri gozdnem medu pa je bilo kromatografskih vrhov številčno manj, vendar so ti imeli relativno velike ploščine. Pri uporabi fluorescenčnega detektorja sem najmanjše ploščine kromatografskih vrhov zaznala pri akacijevem, cvetličnem in lipovem medu. Tako UV kot FL analiza sta pokazali, da so imeli vsi trije vzorci kostanjevega medu podobno sestavo. V vzorcih medu mi je z uporabo standardov uspelo identificirati L-tirozin, ki je bil prisoten v vseh vzorcih, in riboflavin, ki je bil prisoten v dveh od treh vzorcev lipovega medu.

Keywords

tekočinska kromatografija visoke ločljivosti;HPLC-UV;HPLC-FL;fluorescenčna detekcija;spektrofotometrija;diplomska dela;

Data

Language: Slovenian
Year of publishing:
Typology: 2.11 - Undergraduate Thesis
Organization: UL FKKT - Faculty of Chemistry and Chemical Technology
Publisher: [T. Majdič]
UDC: 543.544.5HPLC:638.16(043.2)
COBISS: 202179843 Link will open in a new window
Views: 99
Downloads: 28
Average score: 0 (0 votes)
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Other data

Secondary language: English
Secondary title: Determination of fluorescent compounds in honey by high-performance liquid chromatography with UV and fluorescence detection
Secondary abstract: Honey is a natural food produced by bees and can be composed from various sources: from flower nectar or other secretions of living plant parts, or from various species of manna. Chemically, it is a complex mixture of many organic and inorganic compounds, such as sugars, proteins, amino acids, enzymes, vitamins, organic acids, water, minerals and polyphenols. In my thesis, I used spectrophotometric analysis and liquid chromatography to study the content of fluorescent compounds in honey, i. e. compounds that, when relaxing from excited states, emit photons of lower energies or emit light at longer wavelengths. Honey is known to contain many fluorophores, such as polyphenols, vitamins and amino acids. I analyzed 5 species of honey of different botanical origin, 3 samples of each species, which I had to be properly prepare first. I used HPLC with UV and fluorescence detection and then interpreted the results. With UV detection, I detected the least number of compounds, both in terms of concentration and number, in acacia and chestnut honey, while in forest honey, there were fewer chromatographic peaks, but they had relatively large areas. Using a fluorescent detector, I detected the smallest areas of chromatographic peaks in acacia, flower and lime honey. Both UV and FL analysis showed that all three samples of chestnut honey had a similar composition. Using standards, I was able to identify L-tyrosine, which was present in all honey samples, and riboflavin, which was present in two of the three samples of lime honey.
Secondary keywords: HPLC-UV;HPLC-FL;honey;fluorescence;Med;Tekočinska kromatografija;Fluorescenca;Univerzitetna in visokošolska dela;
Type (COBISS): Bachelor thesis/paper
Study programme: 1000373
Embargo end date (OpenAIRE): 1970-01-01
Thesis comment: Univ. v Ljubljani, Fak. za kemijo in kemijsko tehnologijo, UNI Kemija
Pages: 1 spletni vir (1 datoteka PDF (41 str.))
ID: 24473643