Protibakterijska aktivnost didecildimetilamonijevega klorida

Stenšak, Vanesa (author), Jeršek, Barbka (mentor)

Namen diplomske naloge je bil določiti minimalno inhibitorno koncentracijo (MIC) razkužila didecildimetilamonijev klorid (DDAC) za bakterije vrst Staphylococcus aureus, Escherichia coli, Salmonella enterica, Listeria monocytogenes in Bacillus cereus. Uporabili smo metodo razredčevanja v mikrotitrski ploščici in tekoče gojišče triptični sojin bujon (TSB) ter z dodatkom reagenta 2-p-jodofenil-3-p-nitrofenil-5-fentil tetrazolijev klorid (INT) določili vrednosti MIC. Pri dobljenih vrednostih MIC smo nato z metodo štetja kolonij na trdem gojišču TSA (triptični sojin agar) določili število preživelih bakterij. Rezultati so potrdili naše domneve, da so gramnegativne bakterije vrst E. coli in S. enterica bolj odporne proti razkužilu DDAC kot grampozitivne bakterije vrst Staph. aureus in L. monocytogenes. Sporogene bakterije vrste B. cereus so bile med grampozitivnimi bakterijami najbolj občutljive na DDAC. Pri uporabi razkužil v industriji je zelo pomembno upoštevati navodila za njihovo uporabo, vključno s predvidenimi koncentracijami, saj lahko v nasprotnem primeru uporaba razkužil prinese več negativnih kot pozitivnih posledic. Neustrezna uporaba razkužil lahko izzove prilagoditev bakterij ali celo razvoj odpornih sevov. Tako lahko pride tudi do navzkrižne prilagoditve ali odpornosti in s tem do slabše učinkovitosti ali neučinkovitosti drugih biocidov kot so na primer antibiotiki.

• Language: Slovenian
• Keywords: razkužila, didecildimetilamonijev klorid, DDAC, protibakterijska učinkovitost, razredčevanje v mikrotitrski ploščici, minimalna inhibitorna koncentracija, Staphylococcus aureus, Escherichia coli, Salmonella enterica, Listeria monocytogenes, Bacillus cereus
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: BF - Biotechnical Faculty
• Publisher: [V. Stenšak]
• Year: 2018
• PID: 20.500.12556/RUL-103124
• UDC: 579.24:615.281
• COBISS.SI-ID: 4949624
• Publication date in RUL: 14.09.2018

STENŠAK, Vanesa, 2018, Protibakterijska aktivnost didecildimetilamonijevega klorida [online]. Bachelor’s thesis. V. Stenšak. [Accessed 1 April 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=103124

Secondary language

• Language: English
• Title: Antibacterial activity of didecydimethylammonium chloride

Abstract

The aim of thesis was to determine minimal inhibitory concentration (MIC) for didecyldimethylammonium chloride (DDAC) for Staphylococcus aureus, Escherichia coli, Salmonella enterica, Listeria monocytogenes and Bacillus cereus. Broth microdilution method with tryptic soybean broth (TSB) was used. By adding 2-p-iodophenyl-3-p-nitrophenyl-5-phenyl tetrazolium chloride (INT) reagent, MIC values were determined. At DDAC concentrations that correspond MIC values the number of surviving bacteria was determined by plate count method. The results confirmed our prediction that gram-negative bacteria of E. coli and S. enterica are more resistant to DDAC than gram-positive bacteria of Staph. aureus and L. monocytogenes. Spore forming bacteria of B. cereus were the most sensitive to DDAC among gram-positive bacteria. When using disinfectants in industry it is very important to follow the instructions for their use, including the anticipated concentrations. Inappropriate usage of disinfectants may have more negative than positive consequences and can lead to adaptation of bacteria or even a development of resistant strains. This can also lead to cross-adaptation or cross-resistance, thus lowering efficiency or inefficiency of other biocides, such as antibiotics.

• Keywords: disinfectants, didecyldimethylammonium chloride, DDAC, antibacterial efficiency, microdilution method, minimal inhibitory concentration, Staphylococcus aureus, Escherichia coli, Salmonella enterica, Listeria monocytogenes, Bacillus cereus