{"id":{"repo_id":"aachen","oai_identifier":"oai:publications.rwth-aachen.de:62184"},"canonical_url":"https://search.dev.ndltd.org/etd/aachen/oai:publications.rwth-aachen.de:62184","repository":{"repo_id":"aachen","name":"RWTH Aachen University","base_url":"https://publications.rwth-aachen.de/oai2d"},"display":{"title":"Substratselektivität von Lipasen bei der Veresterung und Umesterung cis-trans-isomerer Fettsäuren und Fettsäureester","abstract":"The aim of this doctoral thesis was the systematic determination of substrate selectivity of lipases towards unsaturated fatty acids and fatty acid esters with respect to position and configuration of C=C-double bonds. First, the substrate selectivity of 39 lipases from microorganisms, plants and animal tissue has been examined in the esterification of cis- and trans-9-octadecenoic acid (oleic and elaidic acid respectively) with n-butanol in n-hexane. While most of the lipases were unspecific towards the isomeric 9-octadecenoic acids, lipases from Candida cylindracea and Mucor miehei had a strong preference for the cis-9-isomer and catalysed the esterification of oleic acid 3-4 times faster than the reaction of elaidic acid. Only Candida antarctica lipase A favoured the trans-9-isomer as substrate and esterified elaidic acid 15 times faster than oleic acid. Examining the substrate selectivity in the esterification of linoleic (all-cis-9,12-octadecadienoic) acid, linolenic (all-cis-9,12,15-octadecatrienoic) acid and their all-trans-isomers with n-butanol in n-hexane as well as in the transesterification of cis/trans-isomeric 9,12-octadecadienoic acid methyl esters with n-butanol in n-hexane, once again lipases from Candida antarctica and Mucor miehei preferred fatty acids and fatty acid esters with a (first) cis double bond in delta-9-position, while the lipase A from Candida antarctica accepted trans-9-unsaturated substrates with high selectivity. Furthermore, lipases from Candida cylindracea and Mucor miehei as well as the lipase A from Candida antarctica has been used as biocatalysts in the esterification of the commercially available conjugated linoleic acid (CLA) isomers cis-9,trans-11-, cis-9,cis-11-, trans-9,trans-11- and trans-10,cis-12-octadecadienoic acid with n-butanol in n-hexane. As expexted, the cis-9-selective lipases from Candida cylindracea and Mucor miehei had a preference for the cis-9,trans-11-octadecadienoic acid, while the Candida antarctica lipase A favoured the trans-9, trans-11-isomer as substrate. Moreover, lipase from Candida cylindracea and lipase A from Candida antarctica were able to discriminate between cis-9,trans-11- and trans-10,cis-12-octadecadienoic acid. Therefore, these lipases has been used for the enzymatic fractionation of individual CLA-isomers, especially for the enrichment of the bioactive cis-9,trans-11-linoleic acid. Last but not least the substrate selecitvity of several microbial lipases towards cis/trans-isomeric octadecenoic acids and acid esters with C=C-double bond in the delta-6-, delta-7-, delta-8-, delta-10-, delta-11-, delta-12- and delta-13-position has been examined in the esterification and transesterification with n-butanol in n-hexane. Depending on the position of the C=C-double bond, lipases of Candida cylindracea and Mucor miehei preferred either the trans-isomer (even position: delta-6, delta-8, delta-10) or the cis-isomer (odd position: delta-7, delta-9, delta-11), while Candida antarctica lipase A always accepted the trans-isomer as substrate.","abstract_html":"The aim of this doctoral thesis was the systematic determination of substrate selectivity of lipases towards unsaturated fatty acids and fatty acid esters with respect to position and configuration of C=C-double bonds. First, the substrate selectivity of 39 lipases from microorganisms, plants and animal tissue has been examined in the esterification of cis- and trans-9-octadecenoic acid (oleic and elaidic acid respectively) with n-butanol in n-hexane. While most of the lipases were unspecific towards the isomeric 9-octadecenoic acids, lipases from Candida cylindracea and Mucor miehei had a strong preference for the cis-9-isomer and catalysed the esterification of oleic acid 3-4 times faster than the reaction of elaidic acid. Only Candida antarctica lipase A favoured the trans-9-isomer as substrate and esterified elaidic acid 15 times faster than oleic acid. Examining the substrate selectivity in the esterification of linoleic (all-cis-9,12-octadecadienoic) acid, linolenic (all-cis-9,12,15-octadecatrienoic) acid and their all-trans-isomers with n-butanol in n-hexane as well as in the transesterification of cis/trans-isomeric 9,12-octadecadienoic acid methyl esters with n-butanol in n-hexane, once again lipases from Candida antarctica and Mucor miehei preferred fatty acids and fatty acid esters with a (first) cis double bond in delta-9-position, while the lipase A from Candida antarctica accepted trans-9-unsaturated substrates with high selectivity. Furthermore, lipases from Candida cylindracea and Mucor miehei as well as the lipase A from Candida antarctica has been used as biocatalysts in the esterification of the commercially available conjugated linoleic acid (CLA) isomers cis-9,trans-11-, cis-9,cis-11-, trans-9,trans-11- and trans-10,cis-12-octadecadienoic acid with n-butanol in n-hexane. As expexted, the cis-9-selective lipases from Candida cylindracea and Mucor miehei had a preference for the cis-9,trans-11-octadecadienoic acid, while the Candida antarctica lipase A favoured the trans-9, trans-11-isomer as substrate. Moreover, lipase from Candida cylindracea and lipase A from Candida antarctica were able to discriminate between cis-9,trans-11- and trans-10,cis-12-octadecadienoic acid. Therefore, these lipases has been used for the enzymatic fractionation of individual CLA-isomers, especially for the enrichment of the bioactive cis-9,trans-11-linoleic acid. Last but not least the substrate selecitvity of several microbial lipases towards cis/trans-isomeric octadecenoic acids and acid esters with C=C-double bond in the delta-6-, delta-7-, delta-8-, delta-10-, delta-11-, delta-12- and delta-13-position has been examined in the esterification and transesterification with n-butanol in n-hexane. Depending on the position of the C=C-double bond, lipases of Candida cylindracea and Mucor miehei preferred either the trans-isomer (even position: delta-6, delta-8, delta-10) or the cis-isomer (odd position: delta-7, delta-9, delta-11), while Candida antarctica lipase A always accepted the trans-isomer as substrate.","abstract_has_math":false,"creators":["Borgdorf, Robert"],"institution":"Publikationsserver der RWTH Aachen University","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Warwel, Siegfried"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2005,"date_issued":"2005","date_published":"2005","updated_at":"2026-07-30T19:43:19Z","subjects":["info:eu-repo/classification/ddc/570","Biowissenschaften, Biologie","Lipase","Substratselektivität","Veresterung","Fettsäuren","cis/trans-Isomere","substrate selectivity","esterification","fatty acids","cis/trans-isomers"],"languages":["ger"],"rights":["info:eu-repo/semantics/openAccess"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-123773%22"],"render_values":[{"text":"https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-123773%22","href":"https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-123773%22","code":true}]}]},"links":{"outbound_url":"https://publications.rwth-aachen.de/record/62184","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Warwel, Siegfried"]},{"key":"dc:creator","label":"Author","values":["Borgdorf, Robert"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:coverage","label":"Dc Coverage","values":["DE"]},{"key":"dc:date","label":"Dc Date","values":["2005"]},{"key":"dc:publisher","label":"Institution","values":["Publikationsserver der RWTH Aachen University"]},{"key":"dc:relation","label":"Dc Relation","values":["info:eu-repo/semantics/altIdentifier/urn/urn:nbn:de:hbz:82-opus-13165"]},{"key":"dc:type","label":"Dc Type","values":["info:eu-repo/semantics/doctoralThesis","info:eu-repo/semantics/publishedVersion"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["info:eu-repo/classification/ddc/570","Biowissenschaften, Biologie","Lipase","Substratselektivität","Veresterung","Fettsäuren","cis/trans-Isomere","substrate selectivity","esterification","fatty acids","cis/trans-isomers"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["ger"]},{"key":"dc:rights","label":"Dc Rights","values":["info:eu-repo/semantics/openAccess"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://publications.rwth-aachen.de/record/62184","https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-123773%22"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["The aim of this doctoral thesis was the systematic determination of substrate selectivity of lipases towards unsaturated fatty acids and fatty acid esters with respect to position and configuration of C=C-double bonds. First, the substrate selectivity of 39 lipases from microorganisms, plants and animal tissue has been examined in the esterification of cis- and trans-9-octadecenoic acid (oleic and elaidic acid respectively) with n-butanol in n-hexane. While most of the lipases were unspecific towards the isomeric 9-octadecenoic acids, lipases from Candida cylindracea and Mucor miehei had a strong preference for the cis-9-isomer and catalysed the esterification of oleic acid 3-4 times faster than the reaction of elaidic acid. Only Candida antarctica lipase A favoured the trans-9-isomer as substrate and esterified elaidic acid 15 times faster than oleic acid. Examining the substrate selectivity in the esterification of linoleic (all-cis-9,12-octadecadienoic) acid, linolenic (all-cis-9,12,15-octadecatrienoic) acid and their all-trans-isomers with n-butanol in n-hexane as well as in the transesterification of cis/trans-isomeric 9,12-octadecadienoic acid methyl esters with n-butanol in n-hexane, once again lipases from Candida antarctica and Mucor miehei preferred fatty acids and fatty acid esters with a (first) cis double bond in delta-9-position, while the lipase A from Candida antarctica accepted trans-9-unsaturated substrates with high selectivity. Furthermore, lipases from Candida cylindracea and Mucor miehei as well as the lipase A from Candida antarctica has been used as biocatalysts in the esterification of the commercially available conjugated linoleic acid (CLA) isomers cis-9,trans-11-, cis-9,cis-11-, trans-9,trans-11- and trans-10,cis-12-octadecadienoic acid with n-butanol in n-hexane. As expexted, the cis-9-selective lipases from Candida cylindracea and Mucor miehei had a preference for the cis-9,trans-11-octadecadienoic acid, while the Candida antarctica lipase A favoured the trans-9, trans-11-isomer as substrate. Moreover, lipase from Candida cylindracea and lipase A from Candida antarctica were able to discriminate between cis-9,trans-11- and trans-10,cis-12-octadecadienoic acid. Therefore, these lipases has been used for the enzymatic fractionation of individual CLA-isomers, especially for the enrichment of the bioactive cis-9,trans-11-linoleic acid. Last but not least the substrate selecitvity of several microbial lipases towards cis/trans-isomeric octadecenoic acids and acid esters with C=C-double bond in the delta-6-, delta-7-, delta-8-, delta-10-, delta-11-, delta-12- and delta-13-position has been examined in the esterification and transesterification with n-butanol in n-hexane. Depending on the position of the C=C-double bond, lipases of Candida cylindracea and Mucor miehei preferred either the trans-isomer (even position: delta-6, delta-8, delta-10) or the cis-isomer (odd position: delta-7, delta-9, delta-11), while Candida antarctica lipase A always accepted the trans-isomer as substrate."]},{"key":"dc:source","label":"Dc Source","values":["Aachen : Publikationsserver der RWTH Aachen University IV, 238 S. : graph. Darst. (2005). = Aachen, Techn. Hochsch., Diss., 2005"]},{"key":"dc:title","label":"Title","values":["Substratselektivität von Lipasen bei der Veresterung und Umesterung cis-trans-isomerer Fettsäuren und Fettsäureester"]}]}],"canonical_facts":{"dc:contributor":["Warwel, Siegfried"],"dc:coverage":["DE"],"dc:creator":["Borgdorf, Robert"],"dc:date":["2005"],"dc:description":["The aim of this doctoral thesis was the systematic determination of substrate selectivity of lipases towards unsaturated fatty acids and fatty acid esters with respect to position and configuration of C=C-double bonds. First, the substrate selectivity of 39 lipases from microorganisms, plants and animal tissue has been examined in the esterification of cis- and trans-9-octadecenoic acid (oleic and elaidic acid respectively) with n-butanol in n-hexane. While most of the lipases were unspecific towards the isomeric 9-octadecenoic acids, lipases from Candida cylindracea and Mucor miehei had a strong preference for the cis-9-isomer and catalysed the esterification of oleic acid 3-4 times faster than the reaction of elaidic acid. Only Candida antarctica lipase A favoured the trans-9-isomer as substrate and esterified elaidic acid 15 times faster than oleic acid. Examining the substrate selectivity in the esterification of linoleic (all-cis-9,12-octadecadienoic) acid, linolenic (all-cis-9,12,15-octadecatrienoic) acid and their all-trans-isomers with n-butanol in n-hexane as well as in the transesterification of cis/trans-isomeric 9,12-octadecadienoic acid methyl esters with n-butanol in n-hexane, once again lipases from Candida antarctica and Mucor miehei preferred fatty acids and fatty acid esters with a (first) cis double bond in delta-9-position, while the lipase A from Candida antarctica accepted trans-9-unsaturated substrates with high selectivity. Furthermore, lipases from Candida cylindracea and Mucor miehei as well as the lipase A from Candida antarctica has been used as biocatalysts in the esterification of the commercially available conjugated linoleic acid (CLA) isomers cis-9,trans-11-, cis-9,cis-11-, trans-9,trans-11- and trans-10,cis-12-octadecadienoic acid with n-butanol in n-hexane. As expexted, the cis-9-selective lipases from Candida cylindracea and Mucor miehei had a preference for the cis-9,trans-11-octadecadienoic acid, while the Candida antarctica lipase A favoured the trans-9, trans-11-isomer as substrate. Moreover, lipase from Candida cylindracea and lipase A from Candida antarctica were able to discriminate between cis-9,trans-11- and trans-10,cis-12-octadecadienoic acid. Therefore, these lipases has been used for the enzymatic fractionation of individual CLA-isomers, especially for the enrichment of the bioactive cis-9,trans-11-linoleic acid. Last but not least the substrate selecitvity of several microbial lipases towards cis/trans-isomeric octadecenoic acids and acid esters with C=C-double bond in the delta-6-, delta-7-, delta-8-, delta-10-, delta-11-, delta-12- and delta-13-position has been examined in the esterification and transesterification with n-butanol in n-hexane. Depending on the position of the C=C-double bond, lipases of Candida cylindracea and Mucor miehei preferred either the trans-isomer (even position: delta-6, delta-8, delta-10) or the cis-isomer (odd position: delta-7, delta-9, delta-11), while Candida antarctica lipase A always accepted the trans-isomer as substrate."],"dc:identifier":["https://publications.rwth-aachen.de/record/62184","https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-123773%22"],"dc:language":["ger"],"dc:publisher":["Publikationsserver der RWTH Aachen University"],"dc:relation":["info:eu-repo/semantics/altIdentifier/urn/urn:nbn:de:hbz:82-opus-13165"],"dc:rights":["info:eu-repo/semantics/openAccess"],"dc:source":["Aachen : Publikationsserver der RWTH Aachen University IV, 238 S. : graph. Darst. (2005). = Aachen, Techn. Hochsch., Diss., 2005"],"dc:subject":["info:eu-repo/classification/ddc/570","Biowissenschaften, Biologie","Lipase","Substratselektivität","Veresterung","Fettsäuren","cis/trans-Isomere","substrate selectivity","esterification","fatty acids","cis/trans-isomers"],"dc:title":["Substratselektivität von Lipasen bei der Veresterung und Umesterung cis-trans-isomerer Fettsäuren und Fettsäureester"],"dc:type":["info:eu-repo/semantics/doctoralThesis","info:eu-repo/semantics/publishedVersion"]},"updated_at":"2026-07-30T19:43:19Z"}