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Laurencia chemistry : Structural diversity chemotaxonomy and bioactive properties of halogenated metabolites

Red algae genus Laurencia is known to be prolific producer of halogenated metabolites such as brominated indoles, terpenes and C15 acetogenins. Malaysian waters are rich with many species of Laurencia, but very few are documented and published. In this investigation, we have analyzed the chemical co...

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Main Author: Takashi Kamada
Format: Thesis
Language:English
English
Published: 2013
Subjects:
QK504-(638) Cryptogams
Online Access:https://eprints.ums.edu.my/id/eprint/41888/1/24%20PAGES.pdf
https://eprints.ums.edu.my/id/eprint/41888/2/FULLTEXT.pdf
https://eprints.ums.edu.my/id/eprint/41888/
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spelling my.ums.eprints.418882024-12-10T02:46:28Z https://eprints.ums.edu.my/id/eprint/41888/ Laurencia chemistry : Structural diversity chemotaxonomy and bioactive properties of halogenated metabolites Takashi Kamada QK504-(638) Cryptogams Red algae genus Laurencia is known to be prolific producer of halogenated metabolites such as brominated indoles, terpenes and C15 acetogenins. Malaysian waters are rich with many species of Laurencia, but very few are documented and published. In this investigation, we have analyzed the chemical composition of L. similis, L. snackeyi, L. majuscula and L. nangii. A total of 72 secondary metabolites including 17 new compounds were isolated. Laurencia similis contained 1 new and 6 known metabolites that belongs to brominated indoles and non-halogenated aristolan type. Laurencia snackeyi contained 2 new and 15 known metabolites of snyderane, monocyclofarnesol, cuparane, cyclolaurane and chamigrene types. Laurencia majuscula produced 12 new and 14 known metabolites of chamigrene, rhodolaurane and omphalane types. Laurencia nangii contained 2 new and 20 known metabolites of acetogenins, sesquiterpenes, diterpenes and triterpenes chemical types. It also revealed the possible presence of "chemical race" in L. snackeyi with the isolation of chamigrene, cuparane and cyclolaurane type compounds. First record of Laurencia derived omphalane type halogenated secondary metabolites were isolated from populations of L. majuscula. It was also clear that L. majuscula is present in two chemical types; 1) population that produces elatol, laurencenone B and 2-chloro-3-hydroxy-α-chamigren-9-one, 2) population that produces (E)-10,15-dibromo-9-hydroxy-chamigra-1,3(15),7(14)-triene and (Z)-10,15-dibromo-9-hydroxy-chamigra-1,3(15),7(14)-triene. Laurencia nangii consist of two chemical races; 1) race that produces C15 acetylenes and terpenes, 2) race that produces C15 bromoallenes and terpenes. All the isolated compounds were subjected to biological activity evaluations such as antibacterial, cytotoxic and antiinflammatory activities. Potent antibacterial activities were observed in α-chamigrenes and brominated indole. Cytotoxic activities, particularly against Adult T-Cell Leukemia were seen in α-chamigrene, β-chamigrene, rhodolaurane and snyderane type compounds. While, strong anti-inflammatory activity was exhibited by aplysistatin, 5β- hydroxypalisadin B and nangiol. Hence, secondary metabolites from Laurencia have potential to be developed into a lead pharmaceutical metabolites. 2013 Thesis NonPeerReviewed text en https://eprints.ums.edu.my/id/eprint/41888/1/24%20PAGES.pdf text en https://eprints.ums.edu.my/id/eprint/41888/2/FULLTEXT.pdf Takashi Kamada (2013) Laurencia chemistry : Structural diversity chemotaxonomy and bioactive properties of halogenated metabolites. Doctoral thesis, Universiti Malaysia Sabah.
institution Universiti Malaysia Sabah
building UMS Library
collection Institutional Repository
continent Asia
country Malaysia
content_provider Universiti Malaysia Sabah
content_source UMS Institutional Repository
url_provider http://eprints.ums.edu.my/
language English
English
topic QK504-(638) Cryptogams
spellingShingle QK504-(638) Cryptogams
Takashi Kamada
Laurencia chemistry : Structural diversity chemotaxonomy and bioactive properties of halogenated metabolites
description Red algae genus Laurencia is known to be prolific producer of halogenated metabolites such as brominated indoles, terpenes and C15 acetogenins. Malaysian waters are rich with many species of Laurencia, but very few are documented and published. In this investigation, we have analyzed the chemical composition of L. similis, L. snackeyi, L. majuscula and L. nangii. A total of 72 secondary metabolites including 17 new compounds were isolated. Laurencia similis contained 1 new and 6 known metabolites that belongs to brominated indoles and non-halogenated aristolan type. Laurencia snackeyi contained 2 new and 15 known metabolites of snyderane, monocyclofarnesol, cuparane, cyclolaurane and chamigrene types. Laurencia majuscula produced 12 new and 14 known metabolites of chamigrene, rhodolaurane and omphalane types. Laurencia nangii contained 2 new and 20 known metabolites of acetogenins, sesquiterpenes, diterpenes and triterpenes chemical types. It also revealed the possible presence of "chemical race" in L. snackeyi with the isolation of chamigrene, cuparane and cyclolaurane type compounds. First record of Laurencia derived omphalane type halogenated secondary metabolites were isolated from populations of L. majuscula. It was also clear that L. majuscula is present in two chemical types; 1) population that produces elatol, laurencenone B and 2-chloro-3-hydroxy-α-chamigren-9-one, 2) population that produces (E)-10,15-dibromo-9-hydroxy-chamigra-1,3(15),7(14)-triene and (Z)-10,15-dibromo-9-hydroxy-chamigra-1,3(15),7(14)-triene. Laurencia nangii consist of two chemical races; 1) race that produces C15 acetylenes and terpenes, 2) race that produces C15 bromoallenes and terpenes. All the isolated compounds were subjected to biological activity evaluations such as antibacterial, cytotoxic and antiinflammatory activities. Potent antibacterial activities were observed in α-chamigrenes and brominated indole. Cytotoxic activities, particularly against Adult T-Cell Leukemia were seen in α-chamigrene, β-chamigrene, rhodolaurane and snyderane type compounds. While, strong anti-inflammatory activity was exhibited by aplysistatin, 5β- hydroxypalisadin B and nangiol. Hence, secondary metabolites from Laurencia have potential to be developed into a lead pharmaceutical metabolites.
format Thesis
author Takashi Kamada
author_facet Takashi Kamada
author_sort Takashi Kamada
title Laurencia chemistry : Structural diversity chemotaxonomy and bioactive properties of halogenated metabolites
title_short Laurencia chemistry : Structural diversity chemotaxonomy and bioactive properties of halogenated metabolites
title_full Laurencia chemistry : Structural diversity chemotaxonomy and bioactive properties of halogenated metabolites
title_fullStr Laurencia chemistry : Structural diversity chemotaxonomy and bioactive properties of halogenated metabolites
title_full_unstemmed Laurencia chemistry : Structural diversity chemotaxonomy and bioactive properties of halogenated metabolites
title_sort laurencia chemistry : structural diversity chemotaxonomy and bioactive properties of halogenated metabolites
publishDate 2013
url https://eprints.ums.edu.my/id/eprint/41888/1/24%20PAGES.pdf
https://eprints.ums.edu.my/id/eprint/41888/2/FULLTEXT.pdf
https://eprints.ums.edu.my/id/eprint/41888/
_version_ 1818835175276019712
score 13.223943

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