Hiina teepõõsa (Camellia sinensis) ja matepuu (Ilex paraguariensis) ekstraktide antibakteriaalne ja antioksüdantne aktiivsus ning polüfenoolide profiil
Laen...
Kuupäev
2025
Kättesaadav alates
04.09.2025
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Eesti Maaülikool
Abstrakt
Viimastel aastakümnetel on kasvanud huvi looduslike bioaktiivsete ühendite kasutamise vastu toiduainetes. Tee ja mate koostises leiduvad polüfenoolid võivad aidata kaasa toiduainete säilivusaja pikendamisele, pärssides mikroorganismide kasvu ja oksüdatiivseid protsesse. Lõputöö eesmärgiks oli määrata hiina teepõõsa (Camellia sinensis (L.) Kuntze) ja matepuu (Ilex paraguariensis A.St.-Hil.) lehtede vesi- ja etanooliekstraktide antioksüdantne ja antibakteriaalne aktiivsus ning polüfenoolide profiil. Samuti oli eesmärgiks võrrelda ekstrakte omavahel, et selgitada välja kõige efektiivsemad ekstraktid edasiseks kasutamiseks järgnevates tootekatsetes. Hiina teepõõsa lehtedest valmistatud matcha, musta ja rohelise tee lehtede pulbritest ning matepuu lehtede pulbrist valmistatud vesi- ja 30% etanooliekstraktides analüüsiti polüfenoolsete ühendite profiile ja polüfenoolide kogusisaldus (ingl total polyphenol content – TPC) määrati HPLC-DAD-MS abil. Summaarne antioksüdantne aktiivsus (ingl total antioxidant capacity – TAC) mõõdeti 2,2-difenüül-1-pikrüülhüdrasüül (ingl 2,2-diphenyl-1-picrylhydrazyl – DPPH) ja Folin-Ciocalteu meetodite abil. Puljongi mikrolahjenduse meetodil 96-süvendiga mikroplaatidel vastavalt EVS-EN ISO 20776-1:2020 juhistele, määrati tee ja mate ekstraktide minimaalsed inhibeerivad kontsentratsioonid (MIK) toiduainetööstuses toiduohutuse seisukohalt oluliste bakterite, Listeria monocytogenes’e, Staphylococcus aureus’e, Escherichia coli ja Campylobacter jejuni suhtes. Tee ja mate ekstraktides tuvastati kokku 28 polüfenoolset ühendit, mis kuulusid hüdroksübensoehapete, hüdroksükaneelhapete, flavanoolide, flavonoolide ja teepigmentide hulka. Mate ekstraktides domineerisid hüdroksükaneelhapped, kuid tee ekstraktides olid ülekaalus flavanoolid. Polüfenoolide kogusisaldus oli kõrgeim mate ja rohelise tee etanooliekstraktides. Antioksüdantne aktiivsus oli kõrgeim rohelise tee ja matcha tee etanooliekstraktides. Kõik ekstraktid omasid antibakteriaalset aktiivsust S. aureus’e vastu. Kõige efektiivsemad ekstraktid edasistes tootekatsetes kasutamiseks võiksid olla rohelise ja matcha tee etanooliekstraktid nende paremate antibakteriaalsete ja antioksüdantsete omaduste tõttu võrreldes teiste ekstraktidega. Tulemused näitavad, et tee ekstraktidel on potentsiaal olla looduslikeks alternatiivideks sünteetilistele lisaainetele toiduainetööstuses. Käesolev töö on seotud Eesti Maaülikooli säästvat arengut toetavate valdkondadega: tervislik ja ohutu toit ning maismaa ja vee ressursside jätkusuutlik kasutamine, samuti ÜRO SDG-ga nr 12: vastutustundlik tarbimine ja tootmine.
Consumers are increasingly more interested in using plant-based additives in food products instead of synthetic ones. Polyphenols found in tea can help extend the shelf life of food products by inhibiting the microbial growth and oxidative processes. The main objectives of this thesis were to find the antioxidant and antibacterial activity of water and ethanol extracts from the leaves of the tea plant (Camellia sinensis (L.) Kuntze) and yerba mate (Ilex paraguariensis A.St.-Hil.), and to determine their polyphenolic profiles. Additionally, the aim was to compare the extracts of the tea plant and yerba mate to identify the most effective extracts for further use in subsequent product trials. The polyphenolic profile and total polyphenol content (TPC) in water and 30% ethanol extracts of matcha, black, and green tea leaf powders made from the leaves of the tea plant, and mate made from yerba mate were analyzed using HPLC-DAD-MS. The total antioxidant capacity (TAC) was measured using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Folin-Ciocalteu methods. The minimum inhibitory concentrations (MIC) of the extracts were determined against bacteria that are prominent in the food industry, Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, and Campylobacter jejuni, using the broth microdilution method on 96-well microplates according to the guidelines of EVS-EN ISO 20776-1:2020. A total of 28 polyphenolic compounds including hydroxybenzoic acids, hydroxycinnamic acids, flavanols, flavonols, and tea pigments were identified in tea and mate extracts. Hydroxycinnamic acids dominated in mate extracts, while flavanols predominated in tea extracts. The total polyphenol content was highest in ethanol extracts of mate and green tea. Antioxidant activity was highest in ethanol extracts of green tea and matcha tea. All extracts showed antibacterial activity against S. aureus. The most effective extracts for further testing in food products could be ethanol extracts of green and matcha tea due to their superior antibacterial and antioxidant properties compared to other extracts. The results of this study show that tea extracts have a potential to be used as alternatives to synthetic additives in the food industry. This work is related to the Estonian University of Life Sciences areas supporting sustainable development: healthy and safe food and sustainable use of land and water resources, as well as UN SDG No. 12: responsible consumption and production.
Consumers are increasingly more interested in using plant-based additives in food products instead of synthetic ones. Polyphenols found in tea can help extend the shelf life of food products by inhibiting the microbial growth and oxidative processes. The main objectives of this thesis were to find the antioxidant and antibacterial activity of water and ethanol extracts from the leaves of the tea plant (Camellia sinensis (L.) Kuntze) and yerba mate (Ilex paraguariensis A.St.-Hil.), and to determine their polyphenolic profiles. Additionally, the aim was to compare the extracts of the tea plant and yerba mate to identify the most effective extracts for further use in subsequent product trials. The polyphenolic profile and total polyphenol content (TPC) in water and 30% ethanol extracts of matcha, black, and green tea leaf powders made from the leaves of the tea plant, and mate made from yerba mate were analyzed using HPLC-DAD-MS. The total antioxidant capacity (TAC) was measured using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Folin-Ciocalteu methods. The minimum inhibitory concentrations (MIC) of the extracts were determined against bacteria that are prominent in the food industry, Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, and Campylobacter jejuni, using the broth microdilution method on 96-well microplates according to the guidelines of EVS-EN ISO 20776-1:2020. A total of 28 polyphenolic compounds including hydroxybenzoic acids, hydroxycinnamic acids, flavanols, flavonols, and tea pigments were identified in tea and mate extracts. Hydroxycinnamic acids dominated in mate extracts, while flavanols predominated in tea extracts. The total polyphenol content was highest in ethanol extracts of mate and green tea. Antioxidant activity was highest in ethanol extracts of green tea and matcha tea. All extracts showed antibacterial activity against S. aureus. The most effective extracts for further testing in food products could be ethanol extracts of green and matcha tea due to their superior antibacterial and antioxidant properties compared to other extracts. The results of this study show that tea extracts have a potential to be used as alternatives to synthetic additives in the food industry. This work is related to the Estonian University of Life Sciences areas supporting sustainable development: healthy and safe food and sustainable use of land and water resources, as well as UN SDG No. 12: responsible consumption and production.
Kirjeldus
Lõputöö
Veterinaarmeditsiini õppekaval
Märksõnad
magistritööd, Ilex paraguariensis, Camellia sinensis, minimaalne inhibeeriv kontsentratsioon, antioksüdantsus, polüfenoolid, Roheline Ülikool (töö toetab EMÜ Rohelise Üikooli põhimõtteid), toiduohutus, mahetoit