Utjecaj okratoksina A na morfologiju i krivulju rasta odabranih sojeva vinskih kvasaca

undergraduate thesis

• Title (english): Effects of ochratoxin A on the morphology and growth curve of selected wine yeast strains
• Author: Helena Juričić
• Mentor: Ksenija Markov (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for General Microbiology and Food Microbiology); Zagreb
• Defense date and country: 2020-09-15, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Nutrition

Abstract

Okratoksin A (OTA) je jedan od najopasnijih mikotoksina, a zbog svoje sveprisutnosti i izraženih toksičnih svojstava, predstavlja ozbiljnu prijetnju ljudskom zdravlju i ekonomiji. U posljednje vrijeme se razvijaju (mikro)biološke metode uklanjanja ili detoksifikacije mikotoksina te je potrebno prikupiti što više saznanja o međusobnom odnosu mikotoksina i mikroorganizama. Budući da postoji jako malo ili uopće ne postoje podatci o utjecaju OTA na morfologiju i broj stanica kvasaca, cilj ovog rada je bio odrediti utjecaj OTA na krivulju rasta i morfologiju stanica kvasaca Saccharomyces cerevisiae, Saccharomyces bayanus i Hanseniaspora uvarum. Mikrobni rast određen je brojanjem poraslih kolonija na čvrstoj hranjivoj podlozi, promjena morfologije stanica kvasaca određena je metodom mikrometrije uz upotrebu objektnog i okularnog mikrometra. Dobiveni rezultati su pokazali da OTA ima neznatan utjecaj na krivulju rasta kvasaca S. cerevisiae, S. bayanus i H. uvarum što nam sugerira da su kvasci razvili mehanizme prilagodbe za uvjete u kojima je prisutan mikotoksin. Također, utjecaj OTA na veličinu stanica ovisi o vremenu izloženosti i koncentraciji OTA.

Abstract (english)

Ochratoxin A (OTA) is one of the most dangerous mycotoxins and due to its overall presence and expressed toxic properties, presents a serious threat to human health and economy. Lately, microbiological methods of removing and detoxificating mycotoxins are developed so it is necessary to gather as much knowledge as possible about interactions between mycotoxins and microorganisms. Since there is very limited or no data at all about OTA impact on yeast cell number and morphology, the aim of this study was to determine OTA influence on the growth curve and morphology of yeasts Saccharomyces cerevisiae, Saccharomyces bayanus and Hanseniaspora uvarum. Microbial growth was determined by counting grown colonies on solid nutrient medium while change in morphology of yeast cells was determined by micrometric method, using the stage and ocular micrometers. Results obtained showed that OTA has minor impact on growth curve of the yeasts S. cerevisiae, S. bayanus and H. uvarum, which suggests that yeasts have developed adaptation mechanisms for conditions where mycotoxin is present. Also, impact of OTA on cell size depends on the exposure time and OTA concentration.

• Keywords: okratoksin A; kvasci; krivulja rasta; morfologija
• Keywords (english): ochratoxin A; yeasts; growth curve; morphology
• Language: croatian
• URN:NBN: urn:nbn:hr:159:269679
• Study programme: Title: Nutrition; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) nutricionizma (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) nutricionizma)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2020-10-27 09:48:07