scholarly journals Bioassay and NMR-Guided  Isolation of Natural Products  from Pacific Marine Invertebrates

2021 ◽  
Author(s):  
◽  
Vidhiya Damodaran
Keyword(s):  
Fatty Acid ◽  
New Zealand ◽  
Nmr Spectroscopy ◽  
Inhibitory Activity ◽  
Marine Invertebrates ◽  
Vaccenic Acid ◽  
Phthalate Esters ◽  
Reversed Phase ◽  
Chemical Degradation ◽  
Phthalate Ester

<p>In the present study, bioassay and NMR approaches were used in combination to guide isolation of two new and three known compounds. An extract library of New Zealand and Tongan marine invertebrates was screened for activity inhibiting the growth of Saccharomyces cerevisiae. From this, ‘hits’ were identified and validated and three New Zealand sponges and a Tongan ascidian were chosen for bulk extraction. These invertebrates were extracted in methanol and purified using normal and reversed-phase chromatography to isolate the compounds of interest. The isolation of compounds was guided by either inhibitory activity towards S. cerevisiae, 1H NMR spectroscopy or a combination of the two. The known trihydroxylated steroid (14) was isolated from the calcareous sponge Leucosolenia sp. A fatty acid and mixture of phthalate esters were isolated from an unidentified Tongan ascidian. The fatty acid was proposed to be cis-vaccenic acid (13) on the basis of 1H and 13C NMR data. The phthalate ester mixture was not purified further. Work on these two compounds was discontinued due to a lack of activity observed in the S. cerevisiae assay and the well-known nature of fatty acids and phthalate esters. Work was also done on an assay targeting the large mechanosensitive channel (MscL) of bacteria. Some parameters were optimised for this assay, however some work remains to be done. The screening of the extract library of New Zealand and Tongan marine invertebrates using this assay was unsuccessful. More studies to better understand the behaviour of this assay are required, some of which are proposed herein. The extraction of the New Zealand marine sponge Haliclona sp. yielded one known and two new 3-alkyl pyridinium alkaloid (3-APA) monomers. The structures of these 3-APA monomers—dehydrohaliclocyclin C (58), dehydrohaliclocyclin F (59) and the known haliclocyclin C (20)—were elucidated using a combination of NMR spectroscopy, mass spectrometry (MS) and chemical degradation. This is the first report of a 3-APA cyclic monomer with unsaturation in the alkyl chain being isolated. 3-APAs were identified as the source of inhibitory activity in the S. cerevisiae assay, however, no inhibitory activity was found for 58, 59 and 20 against the clinically relevant fungus C. albicans.</p>

scholarly journals Bioassay and NMR-Guided  Isolation of Natural Products  from Pacific Marine Invertebrates

2021 ◽  
Author(s):  
◽  
Vidhiya Damodaran
Keyword(s):  
Fatty Acid ◽  
New Zealand ◽  
Nmr Spectroscopy ◽  
Inhibitory Activity ◽  
Marine Invertebrates ◽  
Vaccenic Acid ◽  
Phthalate Esters ◽  
Reversed Phase ◽  
Chemical Degradation ◽  
Phthalate Ester

<p>In the present study, bioassay and NMR approaches were used in combination to guide isolation of two new and three known compounds. An extract library of New Zealand and Tongan marine invertebrates was screened for activity inhibiting the growth of Saccharomyces cerevisiae. From this, ‘hits’ were identified and validated and three New Zealand sponges and a Tongan ascidian were chosen for bulk extraction. These invertebrates were extracted in methanol and purified using normal and reversed-phase chromatography to isolate the compounds of interest. The isolation of compounds was guided by either inhibitory activity towards S. cerevisiae, 1H NMR spectroscopy or a combination of the two. The known trihydroxylated steroid (14) was isolated from the calcareous sponge Leucosolenia sp. A fatty acid and mixture of phthalate esters were isolated from an unidentified Tongan ascidian. The fatty acid was proposed to be cis-vaccenic acid (13) on the basis of 1H and 13C NMR data. The phthalate ester mixture was not purified further. Work on these two compounds was discontinued due to a lack of activity observed in the S. cerevisiae assay and the well-known nature of fatty acids and phthalate esters. Work was also done on an assay targeting the large mechanosensitive channel (MscL) of bacteria. Some parameters were optimised for this assay, however some work remains to be done. The screening of the extract library of New Zealand and Tongan marine invertebrates using this assay was unsuccessful. More studies to better understand the behaviour of this assay are required, some of which are proposed herein. The extraction of the New Zealand marine sponge Haliclona sp. yielded one known and two new 3-alkyl pyridinium alkaloid (3-APA) monomers. The structures of these 3-APA monomers—dehydrohaliclocyclin C (58), dehydrohaliclocyclin F (59) and the known haliclocyclin C (20)—were elucidated using a combination of NMR spectroscopy, mass spectrometry (MS) and chemical degradation. This is the first report of a 3-APA cyclic monomer with unsaturation in the alkyl chain being isolated. 3-APAs were identified as the source of inhibitory activity in the S. cerevisiae assay, however, no inhibitory activity was found for 58, 59 and 20 against the clinically relevant fungus C. albicans.</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.

scholarly journals A non-canonical Δ9-desaturase synthesizing palmitoleic acid identified in the thraustochytrid Aurantiochytrium sp. T66

2021 ◽  
Author(s):  
E-Ming Rau ◽  
Inga Marie Aasen ◽  
Helga Ertesvåg
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Fatty Acid Synthase ◽  
Palmitoleic Acid ◽  
Unsaturated Fatty Acids ◽  
Gene Annotation ◽  
Vaccenic Acid ◽  
Strain Engineering ◽  
Δ9 Desaturase ◽  
Δ12 Desaturase

Abstract Thraustochytrids are oleaginous marine eukaryotic microbes currently used to produce the essential omega-3 fatty acid docosahexaenoic acid (DHA, C22:6 n-3). To improve the production of this essential fatty acid by strain engineering, it is important to deeply understand how thraustochytrids synthesize fatty acids. While DHA is synthesized by a dedicated enzyme complex, other fatty acids are probably synthesized by the fatty acid synthase, followed by desaturases and elongases. Which unsaturated fatty acids are produced differs between different thraustochytrid genera and species; for example, Aurantiochytrium sp. T66, but not Aurantiochytrium limacinum SR21, synthesizes palmitoleic acid (C16:1 n-7) and vaccenic acid (C18:1 n-7). How strain T66 can produce these fatty acids has not been known, because BLAST analyses suggest that strain T66 does not encode any Δ9-desaturase-like enzyme. However, it does encode one Δ12-desaturase-like enzyme. In this study, the latter enzyme was expressed in A. limacinum SR21, and both C16:1 n-7 and C18:1 n-7 could be detected in the transgenic cells. Our results show that this desaturase, annotated T66Des9, is a Δ9-desaturase accepting C16:0 as a substrate. Phylogenetic studies indicate that the corresponding gene probably has evolved from a Δ12-desaturase-encoding gene. This possibility has not been reported earlier and is important to consider when one tries to deduce the potential a given organism has for producing unsaturated fatty acids based on its genome sequence alone. Key points • In thraustochytrids, automatic gene annotation does not always explain the fatty acids produced. • T66Des9 is shown to synthesize palmitoleic acid (C16:1 n-7). • T66des9 has probably evolved from Δ12-desaturase-encoding genes.

scholarly journals Associations between the Bovine Myostatin Gene and Milk Fatty Acid Composition in New Zealand Holstein-Friesian × Jersey-Cross Cows

Animals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1447
Author(s):  
Ishaku L. Haruna ◽  
Yunhai Li ◽  
Ugonna J. Ekegbu ◽  
Hamed Amirpour-Najafabadi ◽  
Huitong Zhou ◽  
...  
Keyword(s):  
Fatty Acid ◽  
New Zealand ◽  
Nucleotide Sequence ◽  
Milk Fat ◽  
Linear Mixed Effect Model ◽  
Polymorphism Analysis ◽  
Mixed Effect ◽  
Myostatin Gene ◽  
Holstein Friesian ◽  
Nucleotide Sequence Variation

The myostatin gene (MSTN), which encodes the protein myostatin, is pleiotropic, and its expression has been associated with both increased and decreased adipogenesis and increased skeletal muscle mass in animals. In this study, the polymerase chain reaction, coupled with single strand conformation polymorphism analysis, was utilized to reveal nucleotide sequence variation in bovine MSTN in 410 New Zealand (NZ) Holstein-Friesian × Jersey (HF × J)-cross cows. These cows ranged from 3 to 9 years of age and over the time studied, produced an average 22.53 ± 2.18 L of milk per day, with an average milk fat content of 4.94 ± 0.17% and average milk protein content of 4.03 ± 0.10%. Analysis of a 406-bp amplicon from the intron 1 region, revealed five nucleotide sequence variants (A–E) that contained seven nucleotide substitutions. Using general linear mixed-effect model analyses the AD genotype was associated with reduced C10:0, C12:0, and C12:1 levels when compared to levels in cows with the AA genotype. These associations in NZ HF × J cross cows are novel, and they suggest that this variation in bovine MSTN could be explored for increasing the amount of milk unsaturated fatty acid and decreasing the amount of saturated fatty acid.

Detection ofcis-vaccenic acid in palm oil by13C NMR spectroscopy

Lipids ◽  
1988 ◽  
Vol 23 (2) ◽  
pp. 140-143 ◽  
Author(s):  
Soon Ng ◽  
Heng Fui Koh
Keyword(s):  
Nmr Spectroscopy ◽  
Palm Oil ◽  
Vaccenic Acid

scholarly journals Angiotensin I-Converting Enzyme Inhibitor Derived from Cross-Linked Oyster Protein

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Cheng-Liang Xie ◽  
Jin-Soo Kim ◽  
Jong-Myung Ha ◽  
Se-Young Choung ◽  
Yeung-Joon Choi
Keyword(s):  
Inhibitory Activity ◽  
Enzyme Inhibitor ◽  
Reversed Phase ◽  
Size Exclusion ◽  
Converting Enzyme ◽  
Spontaneously Hypertensive ◽  
Angiotensin I Converting Enzyme ◽  
Chromatographic Procedure ◽  
Phase Liquid ◽  
Ace Inhibitory

Following cross-linking by microbial transglutaminase, modified oyster proteins were hydrolyzed to improve inhibitory activity against angiotensin-converting enzyme (ACE) inhibitory activity with the use of a single protease, or a combination of six proteases. The oyster hydrolysate with the lowest 50% ACE inhibitory concentration (IC50) of 0.40 mg/mL was obtained by two-step hydrolysis of the cross-linked oyster protein using Protamex and Neutrase. Five ACE inhibitory peptides were purified from the oyster hydrolysate using a multistep chromatographic procedure comprised of ion-exchange, size exclusion, and reversed-phase liquid chromatography. Their sequences were identified as TAY, VK, KY, FYN, and YA, using automated Edman degradation and mass spectrometry. These peptides were synthesized, and their IC50values were measured to be 16.7, 29.0, 51.5, 68.2, and 93.9 μM, respectively. Toxicity of the peptides on the HepG2 cell line was not detected. The oyster hydrolysate also significantly decreased the systolic blood pressure of spontaneously hypertensive rats (SHR). The antihypertensive effect of the oyster hydrolysate on SHR was rapid and long-lasting, compared to commercially obtained sardine hydrolysate. These results suggest that the oyster hydrolysate could be a source of effective nutraceuticals against hypertension.

Seasonal variations in the composition and thermal properties of New Zealand milk fat: I. Fatty-acid composition

1973 ◽  
Vol 40 (2) ◽  
pp. 207-214 ◽  
Author(s):  
I. K. Gray
Keyword(s):  
Fatty Acid Composition ◽  
Thermal Properties ◽  
Fatty Acid ◽  
New Zealand ◽  
Acid Composition ◽  
Negative Correlation ◽  
Seasonal Variations ◽  
Milk Fat ◽  
Significant Negative Correlation ◽  
Weight Percentage

SummaryThe fatty-acid composition of 17 samples of New Zealand milk fat obtained throughout one dairy season is reported.The weight percentage of butyric (C4:0) acid was significantly correlated with that of caproic (C6:0) acid and that of caprylic (C8:0) acid. Percentages of C6:0and C8:0showed a highly significant correlation with each other and with weight percentages of capric (C10:0) and lauric (C12:0) acids.There was a highly significant negative correlation between palmitic (C16:0) and stearic (C18:0) acids and between C4:0and C16:0acids. Oleic (C18:1) acid showed significant negative correlations with C8:0, C10:0, C12:0, myristic (C14:0) and C16:0acids.

Fast approach for fatty acid profiling of dairy products fats using 1 H-NMR spectroscopy

2018 ◽  
Vol 83 ◽  
pp. 52-57 ◽  
Author(s):  
Mihaela Tociu ◽  
Maria-Cristina Todasca ◽  
Aurelia Bratu ◽  
Mihaela Mihalache ◽  
Fulvia Manolache
Keyword(s):  
Fatty Acid ◽  
Nmr Spectroscopy ◽  
Dairy Products ◽  
H Nmr ◽  
Fast Approach ◽  
Fatty Acid Profiling

THE PAPER CHROMATOGRAPHIC FRACTIONATION OF PLANT STERYL ESTERS

1960 ◽  
Vol 38 (1) ◽  
pp. 95-106 ◽  
Author(s):  
A. Kuksis ◽  
J. M. R. Beveridge
Keyword(s):  
Fatty Acid ◽  
Fatty Ester ◽  
Reversed Phase ◽  
Fatty Acid Esters ◽  
Aqueous Acetic Acid ◽  
Acid Moiety ◽  
Steryl Esters ◽  
Paraffin Oil ◽  
Potential Tool ◽  
Acid Esters

The even-numbered C2–C22saturated and the C18-unsaturated fatty acid esters of beta- and gamma-sitosterol, stiginasterol, ergosterol, stigmastanol, and gamma-sitostanol were used separately and in model mixtures for the evaluation of existing and the development of new paper chromatographic methods for the separation and identification of these compounds. Satisfactory separations of the esters were obtained by the ascending reversed phase chromatography on cellulose or glass fiber paper using one of the following systems depending upon the number of carbon atoms in the fatty acid moiety of the ester: C2–C12, aqueous acetic acid/chloroform/paraffin oil; C8–C18, aqueous propionic acid/paraffin oil; C8–C22, acidified aqueous methanol/chloroform/paraffin oil or aqueous butyric acid/paraffin oil. The rate of migration of the esters was inversely proportional to the molecular weight and was increased by the introduction of unsaturation.The increased movement due to unsaturation has been correlated with the number of ethylenic hydrogens, and the possibility that polarity of these atoms might account for this phenomenon is discussed. The reversed phase paper partition chromatography of sterols as their esters is suggested as a potential tool for evaluation of polarity of the various attributes of the sterol nucleus in terms of the chain length of the ester fatty acid. The rule of independent contributions of the constituents of a molecule to its distribution isotherm was observed not to hold in this fatty ester series.

scholarly journals Milk fatty acid profile from grazing buffaloes fed a blend of soybean and linseed oils

2015 ◽  
Vol 67 (3) ◽  
pp. 927-934 ◽  
Author(s):  
G.A. Gagliostro ◽  
E.M. Patiño ◽  
M. Sanchez Negrette ◽  
G. Sager ◽  
L. Castelli ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Milk Fat ◽  
Nutritional Value ◽  
Milk Protein ◽  
Vaccenic Acid ◽  
Total Content ◽  
Experimental Period ◽  
Fat Content ◽  
Milk Fatty Acid ◽  
Milk Protein Content

The aim of the study was to examine the changes in milk fatty acid (FA) profile of grazing buffaloes fed either low (L, 276g/d) or high (H, 572g/d) doses of a blend (70:30, wt/wt) of soybean and linseed oils. Fourteen multiparous Mediterranean buffaloes grazing on a native pasture were fed 4 kg/day of a commercial concentrate containing no supplemental oil over a pre-experimental period of ten days. The baseline milk production and composition and milk FA profile were measured over the last three days. After this pre-experimental period the animals received the same concentrate added with either the L or H oil doses for 26 additional days. Milk yield (g/animal/day) did not differ at the start (1776 ± 522 and 1662 ± 291 for L and H, respectively, P<0.622) or at the end of the trial (4590 ± 991 and 4847 ± 447 in L and H, respectively, P<0.543). Baseline milk fat content (g/kg) averaged 77.1 (±20.5) in L and 74.3 (±9.9) in H (P<0.10) and was reduced (P<0.031) to 60.7 (±23.6) and 49.4 (±11.2) (P<0.0031) respectively after L and H with no differences between treatments (P<0.277). Baseline milk protein content (L=43.2 ± 3.4 and H= 44.3 ± 6.9g/kg) increased after oil supplementation (P<0.0001) in both L (73.2 ± 6.0g/kg) and H (68.4 ± 4.9g/kg) without differences between oil doses (P<0.123). Milk fat content of 14:0 decreased after oil supplementation only in the H treatment (5.29 to 4.03, P<0.007) whereas that of 16:0 was reduced (P<0.001) at both L (24.49 to 19.75g/100g FA) and H (25.92 to 19.17g/100g FA) doses. The reduction of total content of 12:0 to 16:0 was higher (P<0.052) in H (32.02 to 23.93g/100g FA) than L (30.17 to 25.45g/100g FA). Vaccenic acid content increased (P<0.001) from 5.70 to 13.24g/100g FA in L and from 5.25 to 16.77 in H, with higher results in the in H treatment (P<0.001). Baseline rumenic acid was sharply increased (P<0.001) in L (1.80 to 4.09g/100g FA, +127%) and H (1.60 to 4.61g/100g FA, +187%) with no differences between L and H (P<0.19). Overall, these results indicate a pronounced improvement in the nutritional value of milk fat from grazing buffaloes fed little amounts (0.276g/day) of a blend of soybean and linseed oils.

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