The Antimicrobial Activity of Nisin A on Micrococcus Luteus bacteria compared to Tetracycline

Elijah Osarumen Aighobahi & Sura Malik Falih Al-Bahadli

Studenteropgave: Fagmodulprojekt


The discovery of Antibiotics in 1940 was a tremendous breakthrough in the fight against pathogenic
bacteria and the spread of infectious diseases. However, the threat posed by resistant bacteria has
increased the need for an alternative solution to fight bacteria resistance, which has been a global
concern. Moreover, antimicrobial peptides (AMPs) such as Nisin has been widely used as a food
preservative in the food industry and as an alternative approach to fighting the scourge against
bacteria that are resistant to antibiotics. Bacteria resistance is a great concern to the health sector, as
resistant bacteria prevent the effective treatment of diseases and infections.
The aim of this study was to analysed the effectiveness of the AMP activity of Nisin A on
Micrococcus luteus (M. luteus) compared to the antibiotic, Tetracycline. The efficiency was tested
by measuring the two antimicrobial agent’s ability to inhibit the growth of M. luteus with inhibition
zones assay. Therefore, the bactericidal or bacteriostatic effect of the antimicrobial agents was tested
at different concentrations, ranging from 50 μg/ml to 125 μg/ml.
The treatment of Tetracycline against M. luteus showed a bigger zone of inhibition radii of 10.4 mm
at the highest concentration compared to the Nisin A treatment which was 6.94 mm at the same
concentration. Moreover, the inhibition zones for the Nisin A treatment was clearer and more visible
compared to the inhibition zones from the Tetracycline treatment. However, this study showed that
there was no significant difference between the two antimicrobial treatment against M. luteus with a
p-value of 0.29.

UddannelserBasis - Naturvidenskabelig Bacheloruddannelse, (Bachelor uddannelse) Bachelor
Udgivelsesdato29 maj 2017
Antal sider32
VejledereMichelle Vang Mouritzen