scholarly journals Validation of a Spectroscopic Screening Method for Secondary Metabolites from New Zealand Extremophilic Microbes

2021 ◽  
Author(s):  
◽  
Chriselle Deborah Braganza
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Biological Activity ◽  
New Zealand ◽  
Antifungal Activity ◽  
Secondary Metabolites ◽  
Marine Bacteria ◽  
Marine Invertebrates ◽  
Screening Method ◽  
Microbial Cultures ◽  
Anoxybacillus Flavithermus

<p>The existing protocol for the screening of natural products from marine invertebrates and macroalgae has been demonstrated successfully at VUW on multiple occasions. This study describes the evaluation of an adapted version of the protocol to screen liquid microbial cultures. The adapted protocol was carried out using an NMR-guided approach and was used to screen 10 New Zealand extremophilic microbes. Investigation of the bacteria Anoxybacillus flavithermus led to the isolation of the known compound 1-acetyl-β-carboline (25), which was briefly evaluated for its biological activity. A detailed investigation on the marine bacteria Shewanella sp. resulted in the isolation of indole-3-carboxaldehyde (93) and 14 known 2,5-diketopiperazines (36, 38, 41–44, 53, 54, 94–99). Three of the isolated 2,5-DKPs were tested against Saccharomyces cerevisiae to evaluate their antifungal activity, the results of which are also described. Overall, the use of the adapted screening method proved successful to guide the isolation of secondary metabolites from microbial cultures.</p>

scholarly journals Validation of a Spectroscopic Screening Method for Secondary Metabolites from New Zealand Extremophilic Microbes

2021 ◽  
Author(s):  
◽  
Chriselle Deborah Braganza
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Biological Activity ◽  
New Zealand ◽  
Antifungal Activity ◽  
Secondary Metabolites ◽  
Marine Bacteria ◽  
Marine Invertebrates ◽  
Screening Method ◽  
Microbial Cultures ◽  
Anoxybacillus Flavithermus

<p>The existing protocol for the screening of natural products from marine invertebrates and macroalgae has been demonstrated successfully at VUW on multiple occasions. This study describes the evaluation of an adapted version of the protocol to screen liquid microbial cultures. The adapted protocol was carried out using an NMR-guided approach and was used to screen 10 New Zealand extremophilic microbes. Investigation of the bacteria Anoxybacillus flavithermus led to the isolation of the known compound 1-acetyl-β-carboline (25), which was briefly evaluated for its biological activity. A detailed investigation on the marine bacteria Shewanella sp. resulted in the isolation of indole-3-carboxaldehyde (93) and 14 known 2,5-diketopiperazines (36, 38, 41–44, 53, 54, 94–99). Three of the isolated 2,5-DKPs were tested against Saccharomyces cerevisiae to evaluate their antifungal activity, the results of which are also described. Overall, the use of the adapted screening method proved successful to guide the isolation of secondary metabolites from microbial cultures.</p>

scholarly journals Isolation of New Secondary Metabolites from New Zealand Marine Invertebrates

2021 ◽  
Author(s):  
◽  
Joanna M Wojnar
Keyword(s):  
New Zealand ◽  
Methyl Ester ◽  
Secondary Metabolites ◽  
Chromatographic Separation ◽  
Structure Elucidation ◽  
Screening Tool ◽  
Marine Invertebrates ◽  
Toxic Metabolites ◽  
The Family ◽  
New Compounds

<p>This study describes the isolation and structure elucidation of several known and 13 new compounds from New Zealand marine organisms. Furthermore, it describes the development of a digital mask program for the analysis of HSQC spectra of crude sponge extracts. This was used as a screening tool to identify secondary metabolite producers that warranted further analysis. As reports of metabolites from New Zealand nudibranchs are poorly represented in the literature, a study of five New Zealand nudibranch species was undertaken. These coloured and seemingly undefended nudibranchs are known to concentrate or sequester toxic metabolites from their prey, facilitating rapid isolation and structure elucidation of these metabolites. This study resulted in the isolation of a variety of metabolite classes; two new compounds, 13alpha- acetoxypukalide diol (30) and lopholide diol (31) from the nudibranch Tritonia incerta, are described. Examination of the sponge Raspailia agminata resulted in the isolation of a novel family of partially acetylated glycolipids which contain up to six glucose residues. The chromatographic separation of these compounds was a challenge due to the similarity of the congeners and their lack of a chromophore. MSguided isolation eventually led to the purification of agminosides A-E (145-149). An unidentified sponge of the order Dictyoceratida was found to contain a new isomer (186) of the known sesterterpene variabilin. As variabilin-type compounds are predominantly found from sponges of the family Irciniidae, the unidentified sponge is most likely an irciniid. In addition, the sponge contained two prenylated quinones, one of which, 189, is a new isomer of a known sponge metabolite. The sponge Darwinella oxeata contained four new nitrogenous diterpenes of the aplysulphurane (rearranged spongian) skeleton, oxeatamide A (214), isooxeatamide A (215), oxeatamide A 23-methyl ester (216) and oxeatamide B (217).</p>

scholarly journals Natural Products Analysis  of South Pacific Marine  Sponges

2021 ◽  
Author(s):  
◽  
Taitusi Taufa
Keyword(s):  
Natural Products ◽  
New Zealand ◽  
Secondary Metabolites ◽  
Optical Rotation ◽  
Screening Method ◽  
Marine Sponges ◽  
Ic50 Value ◽  
Products Analysis ◽  
New Compounds ◽  
Cacospongia Mycofijiensis

<p>This thesis describes the isolation and structure elucidation of 15 new secondary metabolites from Tongan and New Zealand marine sponges. A total of 18 sponge specimens were subjected to an NMR-based screening method, of which four were analysed in detail. Examination of a two-sponge association, Stelletta crater and Desmacella dendyi from New Zealand, resulted in the isolation of two new 4-methylenesterols, craterols A (94) and B (95). To the best of the author’s knowledge, compounds 94 and 95 represent the first secondary metabolites to be reported from either species. Both 94 and 95 possess a double bond between C-5 and C-6, a feature that is unprecedented in this subgroup of marine natural products. An investigation of a Tongan sponge Zyzzya fuliginosa afforded two new pyrroloquinoline alkaloids, 6-bromodamirone B (182) and makaluvamine W (183). Makaluvamine W (183) contains an oxazole moiety, which is uncommon in this group of natural products. Both 182 and 183 lacked activity against the human promyelocytic leukemia cells (HL-60). Five new compounds were isolated from a Tongan sponge of the genus Leucetta, including two glycerol lipids (238 and 239), three glycerol ethers (244–246) and an imidazole alkaloid (243). Naamidine K (243) is a new addition to the naamidine family, while the glycerol metabolites are non-imidazole alkaloid additions to the group of compounds reported from this genus. A spectroscopic investigation into the Tongan sponge Cacospongia mycofijiensis yielded four new zampanolide analogues (282–285) and a new oxygenated sesquiterpene, isodictyodendrillin A (280). The isolation of the zampanolide analogues gives insight into the structure-activity relationship (SAR) in this family of compounds. Zampanolides B–D (282–284) displayed potent antiproliferative activity towards HL-60 cell lines in the low nanomolar range (3–5 nM), while zampanolide E (285) was significantly less potent with an IC50 value of 306 nM. In addition, the re-isolation of dactylolide (281) and zampanolide A (278) from this sponge, established a firm conclusion regarding the controversial configuration of dactylolide (281), which possesses the same absolute configuration as (–)-zampanolide A (278) and has a levorotatory optical rotation.</p>

scholarly journals The Isolation and Structure Elucidation of Secondary Metabolites from Tongan Marine Invertebrates

2021 ◽  
Author(s):  
◽  
Victoria Helen Woolner
Keyword(s):  
Antifungal Activity ◽  
Secondary Metabolites ◽  
Structure Elucidation ◽  
Sea Cucumber ◽  
Marine Invertebrates ◽  
Marine Sponges ◽  
Marine Organisms ◽  
New Members ◽  
Ic50 Values ◽  
New Compounds

<p>During the course of this study, Tongan marine organisms were investigated for new secondary metabolites. A combination of reversed- and normal-phase chromatographic techniques and NMR spectroscopy was employed, to aid in the isolation and structure elucidation of the five known and four new compounds isolated in this study. A brief investigation into the antifungal activity of Tongan holothurian saponins was instigated in order to compare the activity against saponins isolated from the common New Zealand sea cucumber, Australostichopus mollis. A yeast-based chemical genetics study, determined the antifungal activity, for four partially purified Tongan holothurian extracts, against Saccharomyces cerevisiae, to be similar to neothyonidioside (44), a saponin from A. mollis. This result suggested the antifungal activity to be a common characteristic to sea cucumber saponins. Further interest in secondary metabolites from Tongan marine organisms led this study towards the investigation of Tongan marine sponges. Five sponges were selected for screening, and two chosen for further study which yielded five known compounds (51–53, 61, 62) and four new fascaplysin derivatives; 7-bromoreticulatine,10-bromo-6,7-dimethoxyhomofascaplysin C,10-bromo-6, 7-dimethoxyhomofascaplysin D, and 10-bromohomofascaplysin A (63–66, respectively). Although 63 and 66 are new members of the fascaplysin family solely due to the position of the bromine, it appears that bromination on the A-ring is comparatively rare, with only three of the 24 literature examples displaying A-ring bromination. On the other hand, 64 and 65 present a new sub-class of fascaplysin derivatives due to the presence of a dimethoxy functionality. Both 7-bromoreticulatine (63) and 10-bromohomofascaplysin A (66) were found to be potently cytotoxic in the HL-60 cell line, exhibiting IC50 values of 33.8 and 498 nM, respectively. 10-Bromo-6,7-dimethoxyhomofascaplysins C (64) and D (65) were significantly less cytotoxic with respective IC₅₀ values of 2.7 and 6.0 μΜ. (Abstract continues with diagrams).</p>

Xylaramide, a New Antifungal Compound, and Other Secondary Metabolites from Xylaria longipes

1996 ◽  
Vol 51 (11-12) ◽  
pp. 802-806 ◽  
Author(s):  
Gudrun Schneider ◽  
Heidrun Anke ◽  
Olov Sterner
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Antifungal Activity ◽  
Secondary Metabolites ◽  
Structure Determination ◽  
Biological Activities ◽  
Biological Properties ◽  
The Other ◽  
Antifungal Compound ◽  
Methylsuccinic Acid

Xylaramide (1), possessing potent antifungal activity towards Nematospora coryli and Saccharomyces cerevisiae, was isolated from the culture fluids of the wood-inhabiting ascomycete Xylaria longipes together with tyrosol (2), 2,5-bis(hydroxymethyl)furan (3) and 2-hexylidene- 3-methylsuccinic acid (4). The latter has been known as a Xylaria metabolite for many years. Compounds 2 and 3 have been previously reported from other fungi, whereas 1 is a new natural N -(2-phenylethenyl)-2-hydroxypropanamide. The isolation, structure determination and biological properties of xylaramide are described. The biological activities of the other compounds are included.

scholarly journals Isolation of New Secondary Metabolites from New Zealand Marine Invertebrates

2021 ◽  
Author(s):  
◽  
Joanna M Wojnar
Keyword(s):  
New Zealand ◽  
Methyl Ester ◽  
Secondary Metabolites ◽  
Chromatographic Separation ◽  
Structure Elucidation ◽  
Screening Tool ◽  
Marine Invertebrates ◽  
Toxic Metabolites ◽  
The Family ◽  
New Compounds

<p>This study describes the isolation and structure elucidation of several known and 13 new compounds from New Zealand marine organisms. Furthermore, it describes the development of a digital mask program for the analysis of HSQC spectra of crude sponge extracts. This was used as a screening tool to identify secondary metabolite producers that warranted further analysis. As reports of metabolites from New Zealand nudibranchs are poorly represented in the literature, a study of five New Zealand nudibranch species was undertaken. These coloured and seemingly undefended nudibranchs are known to concentrate or sequester toxic metabolites from their prey, facilitating rapid isolation and structure elucidation of these metabolites. This study resulted in the isolation of a variety of metabolite classes; two new compounds, 13alpha- acetoxypukalide diol (30) and lopholide diol (31) from the nudibranch Tritonia incerta, are described. Examination of the sponge Raspailia agminata resulted in the isolation of a novel family of partially acetylated glycolipids which contain up to six glucose residues. The chromatographic separation of these compounds was a challenge due to the similarity of the congeners and their lack of a chromophore. MSguided isolation eventually led to the purification of agminosides A-E (145-149). An unidentified sponge of the order Dictyoceratida was found to contain a new isomer (186) of the known sesterterpene variabilin. As variabilin-type compounds are predominantly found from sponges of the family Irciniidae, the unidentified sponge is most likely an irciniid. In addition, the sponge contained two prenylated quinones, one of which, 189, is a new isomer of a known sponge metabolite. The sponge Darwinella oxeata contained four new nitrogenous diterpenes of the aplysulphurane (rearranged spongian) skeleton, oxeatamide A (214), isooxeatamide A (215), oxeatamide A 23-methyl ester (216) and oxeatamide B (217).</p>

scholarly journals Dual Effects of Plant Steroidal Alkaloids on Saccharomyces cerevisiae

2006 ◽  
Vol 50 (8) ◽  
pp. 2732-2740 ◽  
Author(s):  
Veronika Simons ◽  
John P. Morrissey ◽  
Maita Latijnhouwers ◽  
Michael Csukai ◽  
Adam Cleaver ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Antifungal Activity ◽  
Secondary Metabolites ◽  
Induced Defense ◽  
Substantial Reduction ◽  
Plant Secondary Metabolites ◽  
Defense Responses ◽  
Membrane Permeabilization ◽  
Ergosterol Biosynthesis ◽  
Induced Defense Responses

ABSTRACT Many plant species accumulate sterols and triterpenes as antimicrobial glycosides. These secondary metabolites (saponins) provide built-in chemical protection against pest and pathogen attack and can also influence induced defense responses. In addition, they have a variety of important pharmacological properties, including anticancer activity. The biological mechanisms underpinning the varied and diverse effects of saponins on microbes, plants, and animals are only poorly understood despite the ecological and pharmaceutical importance of this major class of plant secondary metabolites. Here we have exploited budding yeast (Saccharomyces cerevisiae) to investigate the effects of saponins on eukaryotic cells. The tomato steroidal glycoalkaloidα -tomatine has antifungal activity towards yeast, and this activity is associated with membrane permeabilization. Removal of a single sugar from the tetrasaccharide chain of α-tomatine results in a substantial reduction in antimicrobial activity. Surprisingly, the complete loss of sugars leads to enhanced antifungal activity. Experiments with α-tomatine and its aglycone tomatidine indicate that the mode of action of tomatidine towards yeast is distinct from that of α-tomatine and does not involve membrane permeabilization. Investigation of the effects of tomatidine on yeast by gene expression and sterol analysis indicate that tomatidine inhibits ergosterol biosynthesis. Tomatidine-treated cells accumulate zymosterol rather than ergosterol, which is consistent with inhibition of the sterol C24 methyltransferase Erg6p. However, erg6 and erg3 mutants (but not erg2 mutants) have enhanced resistance to tomatidine, suggesting a complex interaction of erg mutations, sterol content, and tomatidine resistance.

scholarly journals The Isolation and Structure Elucidation of Secondary Metabolites from Tongan Marine Invertebrates

2021 ◽  
Author(s):  
◽  
Victoria Helen Woolner
Keyword(s):  
Antifungal Activity ◽  
Secondary Metabolites ◽  
Structure Elucidation ◽  
Sea Cucumber ◽  
Marine Invertebrates ◽  
Marine Sponges ◽  
Marine Organisms ◽  
New Members ◽  
Ic50 Values ◽  
New Compounds

<p>During the course of this study, Tongan marine organisms were investigated for new secondary metabolites. A combination of reversed- and normal-phase chromatographic techniques and NMR spectroscopy was employed, to aid in the isolation and structure elucidation of the five known and four new compounds isolated in this study. A brief investigation into the antifungal activity of Tongan holothurian saponins was instigated in order to compare the activity against saponins isolated from the common New Zealand sea cucumber, Australostichopus mollis. A yeast-based chemical genetics study, determined the antifungal activity, for four partially purified Tongan holothurian extracts, against Saccharomyces cerevisiae, to be similar to neothyonidioside (44), a saponin from A. mollis. This result suggested the antifungal activity to be a common characteristic to sea cucumber saponins. Further interest in secondary metabolites from Tongan marine organisms led this study towards the investigation of Tongan marine sponges. Five sponges were selected for screening, and two chosen for further study which yielded five known compounds (51–53, 61, 62) and four new fascaplysin derivatives; 7-bromoreticulatine,10-bromo-6,7-dimethoxyhomofascaplysin C,10-bromo-6, 7-dimethoxyhomofascaplysin D, and 10-bromohomofascaplysin A (63–66, respectively). Although 63 and 66 are new members of the fascaplysin family solely due to the position of the bromine, it appears that bromination on the A-ring is comparatively rare, with only three of the 24 literature examples displaying A-ring bromination. On the other hand, 64 and 65 present a new sub-class of fascaplysin derivatives due to the presence of a dimethoxy functionality. Both 7-bromoreticulatine (63) and 10-bromohomofascaplysin A (66) were found to be potently cytotoxic in the HL-60 cell line, exhibiting IC50 values of 33.8 and 498 nM, respectively. 10-Bromo-6,7-dimethoxyhomofascaplysins C (64) and D (65) were significantly less cytotoxic with respective IC₅₀ values of 2.7 and 6.0 μΜ. (Abstract continues with diagrams).</p>

scholarly journals Natural Products Analysis  of South Pacific Marine  Sponges

2021 ◽  
Author(s):  
◽  
Taitusi Taufa
Keyword(s):  
Natural Products ◽  
New Zealand ◽  
Secondary Metabolites ◽  
Optical Rotation ◽  
Screening Method ◽  
Marine Sponges ◽  
Ic50 Value ◽  
Products Analysis ◽  
New Compounds ◽  
Cacospongia Mycofijiensis

<p>This thesis describes the isolation and structure elucidation of 15 new secondary metabolites from Tongan and New Zealand marine sponges. A total of 18 sponge specimens were subjected to an NMR-based screening method, of which four were analysed in detail. Examination of a two-sponge association, Stelletta crater and Desmacella dendyi from New Zealand, resulted in the isolation of two new 4-methylenesterols, craterols A (94) and B (95). To the best of the author’s knowledge, compounds 94 and 95 represent the first secondary metabolites to be reported from either species. Both 94 and 95 possess a double bond between C-5 and C-6, a feature that is unprecedented in this subgroup of marine natural products. An investigation of a Tongan sponge Zyzzya fuliginosa afforded two new pyrroloquinoline alkaloids, 6-bromodamirone B (182) and makaluvamine W (183). Makaluvamine W (183) contains an oxazole moiety, which is uncommon in this group of natural products. Both 182 and 183 lacked activity against the human promyelocytic leukemia cells (HL-60). Five new compounds were isolated from a Tongan sponge of the genus Leucetta, including two glycerol lipids (238 and 239), three glycerol ethers (244–246) and an imidazole alkaloid (243). Naamidine K (243) is a new addition to the naamidine family, while the glycerol metabolites are non-imidazole alkaloid additions to the group of compounds reported from this genus. A spectroscopic investigation into the Tongan sponge Cacospongia mycofijiensis yielded four new zampanolide analogues (282–285) and a new oxygenated sesquiterpene, isodictyodendrillin A (280). The isolation of the zampanolide analogues gives insight into the structure-activity relationship (SAR) in this family of compounds. Zampanolides B–D (282–284) displayed potent antiproliferative activity towards HL-60 cell lines in the low nanomolar range (3–5 nM), while zampanolide E (285) was significantly less potent with an IC50 value of 306 nM. In addition, the re-isolation of dactylolide (281) and zampanolide A (278) from this sponge, established a firm conclusion regarding the controversial configuration of dactylolide (281), which possesses the same absolute configuration as (–)-zampanolide A (278) and has a levorotatory optical rotation.</p>

Charles Francis Adams: diary of a young American taxidermist visiting New Zealand, 1884–1887

2014 ◽  
Vol 41 (1) ◽  
pp. 1-16 ◽  
Author(s):  
B. J. Gill
Keyword(s):  
New Zealand ◽  
San Francisco ◽  
Marine Invertebrates ◽  
Working Life ◽  
Early Years ◽  
Detailed Account ◽  
East Indies ◽  
The Pacific ◽  
Set Up ◽  
White Island

In December 1884 Charles Francis Adams (1857–1893) left Illinois, USA, by train for San Francisco and crossed the Pacific by ship to work as taxidermist at Auckland Museum, New Zealand, until February 1887. He then went to Borneo via several New Zealand ports, Melbourne and Batavia (Jakarta). This paper concerns a diary by Adams that gives a daily account of his trip to Auckland and the first six months of his employment (from January to July 1885). In this period Adams set up a workshop and diligently prepared specimens (at least 124 birds, fish, reptiles and marine invertebrates). The diary continues with three reports of trips Adams made from Auckland to Cuvier Island (November 1886), Karewa Island (December 1886) and White Island (date not stated), which are important early descriptive accounts of these small offshore islands. Events after leaving Auckland are covered discontinuously and the diary ends with part of the ship's passage through the Dutch East Indies (Indonesia), apparently in April 1887. Adams's diary is important in giving a detailed account of a taxidermist's working life, and in helping to document the early years of Auckland Museum's occupation of the Princes Street building.

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