Antimicrobical activity of green tea extract against food borne pathogens : bachelor thesis

Povećan broja oboljenja uzrokovanih patogenim mikroorganizmima koji se nalaze u hrani dovodi do sve veće zabrinutosti potrošača oko sigurnosti hrane. Također, konzumacija hrane pripravljene korištenjem sintetskih aditiva postaje sve upitnija. Stoga, brojne studije nastoje pronaći nove i prirodne aditive, kao što su biljni ekstrakti, koji bi osigurali ispravnu i sigurnu hranu. Upravo je kemijski sastav biljke zaslužan za njen antimikrobni ili antioksidacijski učinak. Kemijski sastav bilja je kompleksan i ima široki spektar djelovanja. Jedni od glavnih kemijskih komponenti zaslužnih za antimikrobno i antioksidacijsko djelovanje su fenolni spojevi. U ovom radu ispitana je antimikrobna aktivnost ekstrakta zelenog čaja na odabrane patogene mikroorganizme kvarenja hrane. Analiza je provedena na pet odabranih vrsta patogenih mikroorganizama: Staphylococcus aureus, Enterococcus faecelis, Listeria monocytogenese, Salmonella enterica i Escherichia coli, korištenjem metode određivanja minimalne inhibitorne koncentracije (MIC) i metodom difuzije u jažicama. Rezultati ispitivanja pokazuju dobru antimikrobnu aktivnost ekstrakta zelenog čaja prema svim testiranim patogenim bakterijama.The increased number of foodborne infections caused by pathogenic microorganisms found in food leads to increased consumer’s concern about food safety. Also, consumption of food processed using synthetic additives becomes more questionable. Therefore, recent studies are focused on finding new and natural sources of additives, such as herbal extracts, which assures food quality and safety. The chemical composition of the plant is responsible for their antimicrobial or antioxidant potencial. Due to its complexity the chemical composition of plants has a wide range of effects. The main chemical components responsible for antimicrobial and antioxidant activity are phenolic compounds. This paper investigated the antimicrobial activity of green tea extracts on selected foodborne pathogenic microorganisms responsible for food deterioration. The analysis was conducted using five different types of microorganisms: Staphylococcus aureus, Enterococcus faecelis, Listeria Monocytogenese, Salmonella enterica and Escherichia coli, determined using the minimum inhibitory concentration (MIC) method and the well diffusion method. The results of the study show good antimicrobial activity of green tea extracts against all tested pathogenic bacteria