izpis_h1_title_alt

Protimikrobna aktivnost etanolnih izvlečkov navadne (Urtica dioica) in mrtve koprive (Lamium sp.)
ID Žalik, Anamarie (Author), ID Smole Možina, Sonja (Mentor) More about this mentor... This link opens in a new window

.pdfPDF - Presentation file, Download (1,73 MB)
MD5: 648B76F647B991DA6B4B3E3B86FA5CC4

Abstract
Za preprečevanje kvara hrane in obvladovanje povzročiteljev okužb in zastrupitev s hrano so še vedno pogosto v uporabi kemijski konzervansi. Med potrošniki so nezaželeni zaradi potencialno negativnih učinkov, vključno z nevarnostmi za zdravje ljudi zaradi kemijskih ostankov v živilskih izdelkih ter pridobivanjem odpornosti mikroorganizmov na uporabljene kemijske učinkovine. S tem se je povečala potreba po iskanju učinkovitih naravnih protimikrobnih sredstev. V diplomskem delu smo preiskovali protimikrobno učinkovitost izvlečkov navadne koprive (Urtica dioica) in dveh vrst mrtve koprive (Lamium orvala in Lamium galeobdolon) na sevih bakterij Listeria monocytogenes, Staphylococcus aureus, Escherichia coli in Pseudomonas fragi, izoliranih iz hrane. Najprej smo iz posušenih rastlin pripravili etanolne izvlečke in z mikrodilucijsko metodo testirali njihovo učinkovanje, kar smo ovrednotili kot minimalno inhibitorno koncentracijo (MIK) in minimalno baktericidno koncentracijo (MBK). Izvlečki so pokazali protimikrobno delovanje pri vseh testiranih bakterijah, pri tem je bil izvleček navadne koprive (U. dioica) nekoliko učinkovitejši kot izvlečka mrtve koprive (L. orvala in L. galeobdolon). Rezultati so pokazali, da je ekstrakt U. dioica primerljivo oz. bolje deloval na gramnegativne bakterije kot na grampozitivne, saj je najbolje inhibiral rast gramnegativne bakterije P. fragi. Protimikrobno učinkovanje izvlečkov mrtve koprive L. orvala in L. galeobdolon je bilo primerljivo, razlika se je pokazala le pri bakteriji P. fragi, ki jo je bolje inhibiral izvleček L. galeobdolon.

Language:Slovenian
Keywords:protimikrobne snovi, rastlinski izvlečki, navadna kopriva, Urtica dioica, mrtva kopriva, Lamium sp., protimikrobna aktivnost, patogene bakterije, metoda mikrodilucije, minimalna inhibitorna koncentracija, minimalna baktericidna koncentracija
Work type:Bachelor thesis/paper
Typology:2.11 - Undergraduate Thesis
Organization:BF - Biotechnical Faculty
Publisher:[A. Žalik]
Year:2019
PID:20.500.12556/RUL-110421 This link opens in a new window
UDC:579.24/.26:547.9
COBISS.SI-ID:5097592 This link opens in a new window
Publication date in RUL:14.09.2019
Views:1225
Downloads:265
Metadata:XML RDF-CHPDL DC-XML DC-RDF
:
Copy citation
Share:Bookmark and Share

Secondary language

Language:English
Title:Antimicrobial activity of ethanolic extracts of stinging (Urtica dioica) and dead nettle (Lamium sp.)
Abstract:
Chemical preservatives are still commonly used to prevent food spoilage and control infectious agents and food poisoning. Among consumers they are undesirable because of the potentially negative effects, including the dangers to human health of chemical residues in food products and the acquisition of resistance of microorganisms to the chemical substances used. This has increased the need to find effective natural antimicrobials. In the thesis we investigated the antimicrobial efficacy of extracts of nettle (Urtica dioica) and two dead nettle species (Lamium orvala and Lamium galeobdolon) on the food strains of Listeria monocytogenes, Staphylococcus aureus, Escherichia coli and Pseudomonas fragi. First, ethanol extracts were prepared from the dried plants and their effect was tested by microdilution method, which was evaluated as minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The extracts showed antimicrobial activity against all bacteria tested, while the extract of stinging nettle (U. dioica) was slightly more effective than the extract of dead nettle (L. orvala and L. galeobdolon). Surprisingly, the results showed that U. dioica extract had a comparable or better effect on gram-negative bacteria than on gram-positive ones, as it best inhibited the growth of gram-negative bacteria P. fragi. The antimicrobial effect of the dead nettle extracts of L. orvala and L. galeobdolon was comparable, with the difference only in P. fragi, which was better inhibited by the L. galeobdolon extract.

Keywords:antimicrobials, plant extracts, stinging nettle, Urtica dioica, dead nettle, Lamium sp., antimicrobial activity, pathogens, microdilution method, minimal inhibitory concentration, minimal bactericidal concentration

Similar documents

Similar works from RUL:
Similar works from other Slovenian collections:

Back