Enzymatic hydrolysis of yeast cell walls for the production of value-added products

Detalhes bibliográficos
Autor(a) principal: Gameiro, Ana Catarina Moreira
Data de Publicação: 2017
Tipo de documento: Dissertação
Idioma: eng
Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
Texto Completo: http://hdl.handle.net/10362/89668
Resumo: Currently at Ohly GmbH, the insoluble yeast cell wall (YCW) fraction is generated as a side-stream product from the Saccharomyces cerevisiae yeast extract production, which is sold for a low profit margin as an additive and supplement for animal feed. The YCW structure exhibits a great source of health-promoting activity and bioactive properties in humans and animals. Therefore, the main aim of this dissertation was to hydrolyse the autolysed YCW through enzymatic digestion, altering its composition and structure, and thereby obtaining different types of unique hydrolysates, which may be used for possible innovative and valuable applications. As there wasn’t any previous work with YCWs at Ohly GmbH, the first step was to develop an enzymatic conversion method establishing the reaction conditions and a hydrolysate product analysis protocol to standardize the process. Once the protocol was determined, the second step was screening 56 commercial enzyme mixtures, which present different hydrolytic activities (such as phospholipase, β-glucanase, chitinase, mannanase, etc) and also characterize the obtained hydrolysates in visual, analytical and chemical terms, such as viscosity, turbidity, solubilisation and phase separation, reducing and free sugars over reaction time. Afterwards, a characterization of glucan- and mannan-oligosaccharides was performed, in order to establish a hydrolysate product selection according to the respective number-average degree of polymerization (DPn), which was also estimated. The DPn values obtained from the enzymatic hydrolysates were also compared and related by their molecular weight (MW) profile, which was analysed by HPLC-SEC. Thus, with a full and detailed report of each hydrolysate product, ideas of new products development were generated, since different DPn values can lead to different product applications. In addition, to obtain a hydrolysate product with an immune-stimulant activity to animal feed, a process optimization (variation of the enzymatic reaction conditions) for a specific commercial enzyme mixture was performed and studied in detail.
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spelling Enzymatic hydrolysis of yeast cell walls for the production of value-added productsYeast cell wallEnzymatic hydrolysisGlucan-oligosaccharidesMannan-oligosaccharidesNumber-average degree of polymerisationMolecular weightDomínio/Área Científica::Engenharia e Tecnologia::Engenharia QuímicaCurrently at Ohly GmbH, the insoluble yeast cell wall (YCW) fraction is generated as a side-stream product from the Saccharomyces cerevisiae yeast extract production, which is sold for a low profit margin as an additive and supplement for animal feed. The YCW structure exhibits a great source of health-promoting activity and bioactive properties in humans and animals. Therefore, the main aim of this dissertation was to hydrolyse the autolysed YCW through enzymatic digestion, altering its composition and structure, and thereby obtaining different types of unique hydrolysates, which may be used for possible innovative and valuable applications. As there wasn’t any previous work with YCWs at Ohly GmbH, the first step was to develop an enzymatic conversion method establishing the reaction conditions and a hydrolysate product analysis protocol to standardize the process. Once the protocol was determined, the second step was screening 56 commercial enzyme mixtures, which present different hydrolytic activities (such as phospholipase, β-glucanase, chitinase, mannanase, etc) and also characterize the obtained hydrolysates in visual, analytical and chemical terms, such as viscosity, turbidity, solubilisation and phase separation, reducing and free sugars over reaction time. Afterwards, a characterization of glucan- and mannan-oligosaccharides was performed, in order to establish a hydrolysate product selection according to the respective number-average degree of polymerization (DPn), which was also estimated. The DPn values obtained from the enzymatic hydrolysates were also compared and related by their molecular weight (MW) profile, which was analysed by HPLC-SEC. Thus, with a full and detailed report of each hydrolysate product, ideas of new products development were generated, since different DPn values can lead to different product applications. In addition, to obtain a hydrolysate product with an immune-stimulant activity to animal feed, a process optimization (variation of the enzymatic reaction conditions) for a specific commercial enzyme mixture was performed and studied in detail.Krüger, DinaRUNGameiro, Ana Catarina Moreira2019-12-10T16:01:30Z2017-04-0420172017-04-04T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisapplication/pdfhttp://hdl.handle.net/10362/89668enginfo:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2024-03-11T04:39:57Zoai:run.unl.pt:10362/89668Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-20T03:37:03.308276Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse
dc.title.none.fl_str_mv Enzymatic hydrolysis of yeast cell walls for the production of value-added products
title Enzymatic hydrolysis of yeast cell walls for the production of value-added products
spellingShingle Enzymatic hydrolysis of yeast cell walls for the production of value-added products
Gameiro, Ana Catarina Moreira
Yeast cell wall
Enzymatic hydrolysis
Glucan-oligosaccharides
Mannan-oligosaccharides
Number-average degree of polymerisation
Molecular weight
Domínio/Área Científica::Engenharia e Tecnologia::Engenharia Química
title_short Enzymatic hydrolysis of yeast cell walls for the production of value-added products
title_full Enzymatic hydrolysis of yeast cell walls for the production of value-added products
title_fullStr Enzymatic hydrolysis of yeast cell walls for the production of value-added products
title_full_unstemmed Enzymatic hydrolysis of yeast cell walls for the production of value-added products
title_sort Enzymatic hydrolysis of yeast cell walls for the production of value-added products
author Gameiro, Ana Catarina Moreira
author_facet Gameiro, Ana Catarina Moreira
author_role author
dc.contributor.none.fl_str_mv Krüger, Dina
RUN
dc.contributor.author.fl_str_mv Gameiro, Ana Catarina Moreira
dc.subject.por.fl_str_mv Yeast cell wall
Enzymatic hydrolysis
Glucan-oligosaccharides
Mannan-oligosaccharides
Number-average degree of polymerisation
Molecular weight
Domínio/Área Científica::Engenharia e Tecnologia::Engenharia Química
topic Yeast cell wall
Enzymatic hydrolysis
Glucan-oligosaccharides
Mannan-oligosaccharides
Number-average degree of polymerisation
Molecular weight
Domínio/Área Científica::Engenharia e Tecnologia::Engenharia Química
description Currently at Ohly GmbH, the insoluble yeast cell wall (YCW) fraction is generated as a side-stream product from the Saccharomyces cerevisiae yeast extract production, which is sold for a low profit margin as an additive and supplement for animal feed. The YCW structure exhibits a great source of health-promoting activity and bioactive properties in humans and animals. Therefore, the main aim of this dissertation was to hydrolyse the autolysed YCW through enzymatic digestion, altering its composition and structure, and thereby obtaining different types of unique hydrolysates, which may be used for possible innovative and valuable applications. As there wasn’t any previous work with YCWs at Ohly GmbH, the first step was to develop an enzymatic conversion method establishing the reaction conditions and a hydrolysate product analysis protocol to standardize the process. Once the protocol was determined, the second step was screening 56 commercial enzyme mixtures, which present different hydrolytic activities (such as phospholipase, β-glucanase, chitinase, mannanase, etc) and also characterize the obtained hydrolysates in visual, analytical and chemical terms, such as viscosity, turbidity, solubilisation and phase separation, reducing and free sugars over reaction time. Afterwards, a characterization of glucan- and mannan-oligosaccharides was performed, in order to establish a hydrolysate product selection according to the respective number-average degree of polymerization (DPn), which was also estimated. The DPn values obtained from the enzymatic hydrolysates were also compared and related by their molecular weight (MW) profile, which was analysed by HPLC-SEC. Thus, with a full and detailed report of each hydrolysate product, ideas of new products development were generated, since different DPn values can lead to different product applications. In addition, to obtain a hydrolysate product with an immune-stimulant activity to animal feed, a process optimization (variation of the enzymatic reaction conditions) for a specific commercial enzyme mixture was performed and studied in detail.
publishDate 2017
dc.date.none.fl_str_mv 2017-04-04
2017
2017-04-04T00:00:00Z
2019-12-10T16:01:30Z
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
dc.type.driver.fl_str_mv info:eu-repo/semantics/masterThesis
format masterThesis
status_str publishedVersion
dc.identifier.uri.fl_str_mv http://hdl.handle.net/10362/89668
url http://hdl.handle.net/10362/89668
dc.language.iso.fl_str_mv eng
language eng
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
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dc.format.none.fl_str_mv application/pdf
dc.source.none.fl_str_mv reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação
instacron:RCAAP
instname_str Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação
instacron_str RCAAP
institution RCAAP
reponame_str Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
collection Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
repository.name.fl_str_mv Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação
repository.mail.fl_str_mv
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