• JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
 
  Bookmark and Share
 
 
Master's Dissertation
DOI
https://doi.org/10.11606/D.60.2021.tde-22032022-092001
Document
Author
Full name
Vitor de Souza Mazucato
E-mail
Institute/School/College
Knowledge Area
Date of Defense
Published
Ribeirão Preto, 2021
Supervisor
Committee
Vieira, Paulo Cezar (President)
Chagas, Fernanda Oliveira das
Silva, Maria Fatima das Graças Fernandes da
Title in Portuguese
Explorando a diversidade química de fungos fitoparasitas de frutos e avaliação de seus potenciais inibitórios de papaína
Keywords in Portuguese
Biotransformação
Colletotrichum horii
Fungos fitopatogênicos
Fusarium guttiforme
Inibidores enzimáticos
Modulação epigenética
Abstract in Portuguese
Neste trabalho foram estudados dois fungos, o Fusarium guttiforme e Colletotrichum horii, e seus potenciais de produzirem inibidores enzimáticos associados a doenças provocadas por esses fungos em abacaxi, mamão e caqui. Utilizou-se a técnica de cocultivo, uma abordagem utilizada atualmente para mimetizar o ambiente natural e obter uma maior diversidade química de compostos produzidos. Além disso, outras estratégias foram utilizadas para induzir a produção de diferentes metabólitos e explorar o potencial destes fungos como a utilização de meio de cultivo diferentes, sendo eles PDB e Czapek, a realização de processos de biotransformação das micotoxinas ácido fusárico (AF), ácido 9,10-desidrofusárico (ADF) e mistura deles e experimento com modificador epigenético, o ácido suberoidroxâmico (ASBH). Os extratos obtidos foram analisados por ressonância magnética nuclear de hidrogênio (RMN de 1H), e técnicas cromatográficas foram utilizadas para isolamento dos compostos, cujas estruturas foram elucidadas por RMN de 1H e espectrometria de massas, totalizando 14 compostos isolados e identificados. Os cultivos axênicos de F. guttiforme e C. horii em meio PDB levaram a produção de três compostos, o ácido fusárico (1), ácido 9,10-desidrofusárico (2) e tirosol (3), enquanto o cocultivo deles levou à produção de outros 4 compostos, o fusarinol (4), complexo do ácido fusárico com magnésio (5), complexo do ácido 9,10-desidrofusárico com magnésio (6) e uma lactona a 5-Butil-5-(hidroximetil)diidrofuranona (7), sendo estes três últimos inéditos na literatura. A variação de meio de cultivo PDB para meio Czapek levou a produção de compostos estruturalmente diferentes, sendo isolado os compostos uracila (8), para-hidroxiacetofenona (9) e a dicetopiperazina ciclo prolina-leucina (10). Os experimentos de biotransformação mostraram que o fusarinol obtido no cocultivo é resultado de um processo de destoxificação de AF pelo fungo C. horii a um composto menos tóxico, além disso foram obtidos outros 3 compostos desse processo, o 7-hidroxifusarinol (11), 9,10-desidrofusarinol (12) e acetato de fusarinila (13), sendo dois deles inéditos. A modulação epigenética com AS frente ao fungo F. guttiforme levou a um extrato com perfil químico diferente do controle, sendo obtidos alguns dos compostos obtidos no cocultivo em meio Czapek e a gibepirona B (14). Estes compostos foram submetidos a ensaio enzimático de inibição da papaína, as maiores atividade inibitória obtidas foram 56, 54 e 30% para os compostos complexo do ácido fusárico com magnésio (5), complexo do ácido 9,10-desidrofusárico com magnésio (6) e acetato de fusarinila (13) respectivamente.
Title in English
Exploring the chemical diversity of phytoparasitic fungi on fruits and evaluating their papain inhibitory potentials
Keywords in English
Biotransformation
Colletotrichum horii
Enzyme Inhibitor
Epigenetic modulation
Fusarium guttiform
Phytopathogenic fungi
Abstract in English
In this work, two fungi, Fusarium guttiforme and Colletotrichum horii, and their potential to produce enzyme inhibitors associated with diseases caused by these fungi in pineapple, papaya and persimmon were studied. Co-cultivation is an approach currently used to mimic the natural environment and obtain a large chemical diversity of produced compounds. In addition, other strategies were used to induce the production of other compounds and explore the potential of these fungi, such as the use of different culture media, namely PDB and Czapek, the performance of biotransformation processes of fusaric acid (AF), 9.10-dehydrofusaric acid (ADF) mycotoxins and their mixture and experiment with epigenetic modifier suberohydroxamic acid (SBHA). The obtained extracts were followed by hydrogen nuclear magnetic resonance (1H NMR), chromatographic techniques were used to isolate the compounds that were elucidated by 1H NMR and mass spectrometry, totaling 14 isolated compounds. Axenic cultivation in PDB medium led to the production of three compounds, fusaric acid (1), 9,10-dehydrofusaric acid (2) and tyrosol (3), while co-cultivation led to the production of another 4 compounds, fusarinol (4), compounds fusaric acid complex with magnesium (5), 9,10-dehydrofusaric acid complex with magnesium (6) and a 5-butyl-5-(hydroxymethyl)dihydrofuranone lactone (7), these last three are unpublished compounds. The variation from the PDB culture medium to the Czapek medium led to the production of totally different compounds, being isolated the compounds uracil (8), p-hydroxyacetophenone (9) and the diketopiperazine cycloproline-leucine (10). The biotransformation experiments showed that the fusarinol obtained in the co-cultivation is the result of a process of detoxification of FA by the fungus C. horii to a less toxic compound, in addition, other 3 compounds were obtained from this process 7-hydroxyfusarinol (11), 9,10-dehydrofusarinol (12) and fusarinyl acetate (13) being two of them unpublished. Epigenetic modulation with SBHA against the fungus F. guttiforme led to an extract with a different chemical profile than the control, being obtained some of the compounds obtained in co-cultivation in Czapek medium and also gibepiyrone B (14). These compounds were submitted to an enzymatic assay against papain, the highest inhibitory activities obtained were 56, 54 and 30% for the compounds fusaric acid complex with magnesium (5), 9,10-dehydrofusaric acid complex with magnesium (6) and fusarinyl acetate (13) respectively.
 
WARNING - Viewing this document is conditioned on your acceptance of the following terms of use:
This document is only for private use for research and teaching activities. Reproduction for commercial use is forbidden. This rights cover the whole data about this document as well as its contents. Any uses or copies of this document in whole or in part must include the author's name.
Publishing Date
2022-04-12
 
WARNING: Learn what derived works are clicking here.
All rights of the thesis/dissertation are from the authors
CeTI-SC/STI
Digital Library of Theses and Dissertations of USP. Copyright © 2001-2024. All rights reserved.