Separacija vrednih spojin iz lupin pistacije s podkritično vodo

diplomsko delo visokošolskega strokovnega študijskega programa I. stopnje

Nina Travnikar (Author), Mojca Škerget (Mentor), Maja Čolnik (Co-mentor)

Abstract

Dandanes je vse večji interes po iskanju najboljšega načina, kako bi lahko odpadno biomaso pretvorili v vredne komponente in energijo ter tako prispevali k ohranjanju okolja. Veliko odpadne biomase najdemo v odpadkih in ostankih živilske industrije, ki so velikokrat samo zavrženi, čeprav bi lahko z uporabo določenih ekstrakcij iz njih separirali vredne spojine, ki bi jih nato koristno uporabili v zdravstveni in farmacevtski industriji. Primer tako odvrženih surovin so lupine pistacije. Pri plodu pistacije je užitna samo sredica, zunanja lupina, ki predstavlja velik delež pistacije, pa je smatrana kot odpadek in se zavrže. V okviru diplomskega dela smo izvajali ekstrakcije lupin pistacije z uporabo podkritične vode pri temperaturi od 150 °C do 250 °C in reakcijskem času od 15 min do 60 min ter rezultate primerjali s konvencionalnimi ekstrakcijami, kjer smo uporabili organski topili aceton in etanol. Preučevali smo vpliv različnih procesnih parametrov (reakcijski čas in temperaturo) na izkoristek ekstrakcije in njihov vpliv na sestavo produktov v ekstraktih. Maksimalni izkoristek ekstrakcije smo ugotovili pri temperaturi 200 °C in reakcijskem času 15 min. Z daljšanjem reakcijskega časa pa je izkoristek pričel upadati v vseh primerih ekstrakcije. V nadaljevanju smo v ekstraktih z UV-Vis spektrofotometričnimi metodami določili vsebnost totalnih fenolov, flavonoidov, ogljikovih hidratov in antioksidativno aktivnost. Maksimalne vsebnosti totalnih flavonoidov (10,18 mg QU/g ekstrakta pri 200 °C in 60 min) in totalnih ogljikovih hidratov (554,52 mg TOH/g materiala pri 60 min in 200 °C) ter maksimalno antioksidativno aktivnost (90,01 % pri 250 °C in pri 60 min) smo določili v primeru, ko smo ekstrakte pridobili s pomočjo podkritične vode, med tem ko smo maksimalne vsebnosti totalnih fenolov (86,17 mg GA/g ekstrakta) določili v primeru konvencionalne ekstrakcije z etanolom. S HPLC metodo smo določili, da je bilo v ekstraktih pridobljenih s podkritično vodo prisotnih največ furfuralov. Rezultati so pokazali, da je podkritična voda bolj primerno topilo za separacijo vrednih spojin iz lupin pistacije kot pa organska topila.

Keywords

lupine pistacije;podkritična voda;organska topila;ekstrakcija;vredne spojine;diplomske naloge;

Data

Language:	Slovenian
Year of publishing:	2022
Typology:	2.11 - Undergraduate Thesis
Organization:	UM FKKT - Faculty of Chemistry and Chemical Engineering
Publisher:	[N. Travnikar]
UDC:	66.061.3:634.574(043.2)
COBISS:	121399555
Views:	11
Downloads:	8
Average score:	0 (0 votes)
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Other data

Secondary language:	English
Secondary title:	Separation of valuble compounds from pistachio shells using subcritical water
Secondary abstract:	Nowadays, there is a growing interest in finding the best way to convert waste biomass into valuable components and energy, thus contributing to the preservation of the environment. A lot of biomass waste is found in food industry waste and residues, which are often only discarded, although certain extractions could be used to separate valuable compounds from them, which could then be used in the health and pharmaceutical industries. An example of such dicarded raw materials are pistachio hulls. In the case of the pistachio nut, only the core is edible, and the outer hull, which represents a large proportion of the pistachio, is considered as waste and is discarded. In this thesis, we preformed an extraction of pistachio hulls using subcritical water at temperatures from 150 °C to 250 °C and reaction time from 15 min to 60 min and compared it with conventional extraction, where we used organic solvents acetone and ethanol. We studied the influence of process parameters (temperature and reaction time) on the extraction yield and their influence on the product composition in the extracts. The highest extraction yield was found at a temperature of 200 °C and a reaction time of 15 min. With further extension of the reaction time, the yield started to decrease in all extraction cases. In the following, we determined the content of total phenols, total flavonoids, total carbohydrates and antioxidant activity of the extracts using UV-Vis spectrophotometric methods. The maximum contents of total flavonoids (10.18 mg QU/g extract at 200 °C and 60 min) and total carbohydrates (554.52 mg TOH/g material at 60 min and 200 °C) and the highest antioxidant activity (90.01 % at 250 °C and at 60 min) was determined in the case when the extracts were obtained with the help of subcritical water, while the maximum content of total phenols (86.17 mg GA/g extract) was determined in the case of conventional extraction with ethanol. Using the HPLC method, we determined that the most furfurals were present in the extracts obtained with subcritical water. From the results, we concluded that subcritical water is a more suitable solvent for the separation of valuable compounds from pistachio shells than acetone or ethanol.
Secondary keywords:	pistachio hulls;subcritical water;organic solvents;extraction;valuable compounds;
Type (COBISS):	Bachelor thesis/paper
Thesis comment:	Univ. v Mariboru, Fak. za kemijo in kemijsko tehnologijo
Pages:	1 spletni vir (1 datoteka PDF (XI, 47 f.))
ID:	16248768