Biotehnološki in toksikološki vidiki plesni rodu Aspergillus

Trajkovska, Sara (author), Jamnik, Polona (mentor), Jeršek, Barbka (comentor)

V diplomski nalogi so obravnavani biotehnološki in toksikološki vidiki plesni rodu Aspergillus. V obsegu biotehnološkega dela so prikazani produkti primarnega in sekundarnega metabolizma plesni. Podan je vpogled v novejše pristope povečanja produkcije citronske kisline in encimov preko izboljševanja produkcijskih sevov vrste A. niger ter povečanje produkcije lovastatina in njegovih derivatov preko izboljševanja produkcijskih sevov vrste A. terreus. V toksikološkem delu so izpostavljene glavne lastnosti, ki so pomembne za tvorbo mikotoksinov pri izbranih vrstah plesni rodu Aspergillus. Opisani so aflatoksini, ki jih tvorijo plesni vrst A. flavus in A. parasiticus, ohratoksin A in fumonizini, ki jih tvorijo plesni vrste A. niger ter razmere, v katerih te plesni lahko predstavljajo tveganje pri produkciji biotehnoloških produktov. Produkcijski sevi plesni vrste A. niger imajo izbisane genske klastre ohratoksina A in fumonizinov in imajo tako onemogočeno njihovo sintezo. Prikazane so tudi razmere, v katerih prihaja do tvorbe (+)-geodina, ki pomeni tveganje pri produkciji lovastatina s plesnimi vrste A. terreus. Z optimizacijo parametrov bioprocesa ter s prekinitvijo genov v genskem klastru (+)-geodina je zagotovljeno pridobivanje lovastatina brez tvorbe tega mikotoksina. Izbris genov v genskih klastrih mikotoksinov ter optimizacija parametrov bioprocesa omogoča proizvodnjo biotehnoloških produktov brez tveganja tvorbe mikotoksinov.

• Language: Slovenian
• Keywords: Aspergillus niger, Aspergillus terreus, citronska kislina, glukoamilaza, lovastatin, mikotoksini, aflatoksin B1, ohratoksin A, fumonizin B2
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: BF - Biotechnical Faculty
• Year: 2024
• PID: 20.500.12556/RUL-159488
• COBISS.SI-ID: 201448451
• Publication date in RUL: 11.07.2024

TRAJKOVSKA, Sara, 2024, Biotehnološki in toksikološki vidiki plesni rodu Aspergillus [online]. Bachelor’s thesis. [Accessed 18 May 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=159488

Secondary language

• Language: English
• Title: Biotechnological and toxicological aspects of molds from Aspergillus genus

Abstract

The diploma thesis discusses the biotechnological and toxicological aspects of the mold Aspergillus. It presents the products of primary and secondary metabolism of these molds within the context of biotechnological applications. The thesis offers insights into recent methods for enhancing the production of citric acid and enzymes by improving the production strains of A. niger, as well as for enhancing the production of lovastatin and its derivatives through improved strains of A. terreus. In the toxicological section, key properties important for the formation of mycotoxins in selected Aspergillus species are highlighted. It describes aflatoxins produced by A. flavus and A. parasiticus, as well as ochratoxin A and fumonisins produced by A. niger, detailing the conditions under which these molds pose a risk in biotechnological product production. It also discusses A. niger strains with gene cluster deletions that prevent the synthesis of ochratoxin A and fumonisins. Additionally, the conditions that pose a risk for the formation of (+)-geodin during lovastatin production from A. terreus molds are outlined. The thesis explains how optimizing bioprocess parameters and disrupting genes in the (+)-geodin gene cluster ensures lovastatin production without mycotoxin formation. Overall, the deletion of mycotoxin gene clusters and optimization of bioprocess parameters enable the safe production of biotechnological products without mycotoxin contamination.

• Keywords: Aspergillus niger, Aspergillus terreus, citric acid, glucoamylase, lovastatin, mycotoxins, aflatoxin B1, ochratoxin A, fumonisin B2