Preživljavanje bakterija Escherichia coli i Acinetobacter junii pri različitim koncentracijama natrijevog klorida

master's thesis

• Title (english): Survival of bacterias Escherichia coli and Acinetobacter junii at various concentrations of sodium chloride
• Author: Angelina Adamović
• Mentor: Jasna Hrenović (mentor)
• Committee member: Jasna Hrenović (predsjednik povjerenstva)
• Committee member: Iva Juranović Cindrić (član povjerenstva)
• Committee member: Ivančica Ternjej (član povjerenstva)
• Committee member: Draginja Mrvoš-Sermek (član povjerenstva)
• Committee member: Jasna Lajtner (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2010, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Istraživano je preživljavanje dviju heterotrofnih bakterija u uvjetima različite koncentracije natrijevog klorida. Obje bakterije mogu doći u morski okoliš putem kanalizacije ili efluenata iz postrojenja za preradu otpadnih voda; Escherichia coli je uobičajena enterička bakterija, a Acinetobacter junii fosfat-uklanjajuća bakterija koja nastanjuje aktivni mulj. Kada su se uzgajale u mediju bogatom nutrijentima (KPK 8700 mg O2 L-1) obje bakterije su se razmnožavale tijekom 72 sata pri koncentracijama natrijevog klorida do 5% za E. coli i do 3,5% za A. junii. Ukupno umiranje E. coli detektirano je nakon 72 h pri koncentraciji natrijevog klorida od 20%. Ukupno umiranje A. junii detektirano je nakon 72 h pri koncentraciji natrijevog klorida od 10%. Kada su iste bakterije uzgajane u mediju siromašnom nutrijentima (KPK 90 mg O2 L-1) multiplikacija E. coli zaustavila se pri koncentraciji natrijevog klorida od 3,5% i višoj, no stanice su mogle preživjeti duži period vremena pri ekstremnim koncentracijama natrijevog klorida od 20 i 30%. Negativan utjecaj natrijevog klorida na A. junii vidljiv je u uvjetima nedostatka organske tvari i brzo umiranje je uočeno pri koncentraciji natrijevog klorida od 3,5% i više. Rezultati pokazuju da su obje bakterije osmotolerantne kad su uzgajane u mediju bogatom nutrijentima, ali ne i u mediju siromašnom nutrijentima.

Abstract (english)

The survival of two heterotrophic bacteria in conditions of various concentrations of sodium chloride was researched. Both bacteria can commonly enter marine environments through sewage or wastewater treatment plant effluents; the Escherichia coli is a common enteric bacterium and Acinetobacter junii is a phosphate-accumulating bacterium inhabiting activated sludge. When cultivated in nutrient rich media (COD 8700 mg O2 L-1), both bacteria were multiplying during 72 h at concentrations of sodium chloride up to 5% for E. coli and 3.5% for A. junii. Total die-off od E. coli was detected at 72 h by sodium chloride concentration of 20%. Total die-off od A. junii was detected at 72 h by sodium chloride concentration of 10%. When the same bacteria were cultured at nutrient depleted media (COD 90 mg O2 L-1), the multiplitation of E. coli stopped at 3.5% of sodium chloride and higher, but the cells were able to survive for longer period of time at extreme sodium chloride concentrations of 20 and 30%. The negative influence of sodium chloride to A. junii was pronounced in conditions of organic matter shortage and rapid die-off was observed at 3.5% of sodium chloride and higher. Both bacteria seemed to be osmotolerant when cultured in nutrient-rich media, but not in nutrient-depleted media.

• Keywords: enterička bakterija; fosfat-uklanjajuća bakterija; razmnožavanje; umiranje; Nutrient Broth
• Keywords (english): enteric bacteria; phosphate-accumulating bacteria; propagation; dying; Nutrient Broth
• Language: croatian
• URN:NBN: urn:nbn:hr:217:053200
• Study programme: Title: Biology and Chemistry; Study programme type: university; Study level: graduate; Academic / professional title: profesor biologije i kemije (profesor biologije i kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2018-03-21 13:52:05