Docosahexaenoic Acid Is Naturally Concentrated at the sn-2 Position in Triacylglycerols of the Australian Thraustochytrid Aurantiochytrium sp. Strain TC 20

The Labyrinthulomycetes or Labyrinthulea are a class of protists that produce a network of filaments that enable the cells to glide along and absorb nutrients. One of the main two Labyrinthulea groups is the thraustochytrids, which are becoming an increasingly recognised and commercially used alternate source of long-chain (LC, ≥C20) omega-3 containing oils. This study demonstrates, to our knowledge for the first time, the regiospecificity of the triacylglycerol (TAG) fraction derived from Australian thraustochytrid Aurantiochytrium sp. strain TC 20 obtained using 13C nuclear magnetic resonance spectroscopy (13C NMR) analysis. The DHA present in the TC 20 TAG fraction was determined to be concentrated in the sn-2 position, with TAG (16:0/22:6/16:0) identified as the main species present. The sn-2 preference is similar to that found in salmon and tuna oil, and differs to seal oil containing largely sn-1,3 LC-PUFA. A higher concentration of sn-2 DHA occurred in the thraustochytrid TC 20 oil compared to that of tuna oil.

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Alkaloids from Mongolian species of Peganum multisectum (Maxim) Bobrov

Mongolian Journal of Chemistry ◽

10.5564/mjc.v16i0.668 ◽

2016 ◽

Vol 16 ◽

pp. 48-53 ◽

Cited By ~ 1

Author(s):

S. Javzan ◽

D. Selenge ◽

N. Amartuvshin ◽

D. Nedelcheva ◽

V Christov ◽

...

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

13C Nmr ◽

Gas Chromatography Mass Spectrometry ◽

Nmr Analysis ◽

1H And 13C Nmr ◽

Aerial Parts ◽

13C Nmr Analysis ◽

Pure Compounds ◽

First Time

Alkaloids of the aerial parts of P. multisectum (Maxim) Bobrov (Zygophyllaceae) growing in Mongolia have been studied by capillary Gas Chromatography-Mass Spectrometry (GC-MS) and Column Chromatography (CC). Four compounds comprising of 2-methylquinoline (1), 9-amino-2, 3,5,6,7,8-hexahydro-1H-cyclopenta [b] quinoline (2), vasicinone (3) and harmine (4) have been determined by GC-MS, while harmine (4), peganine (5), deoxypeganine (6), deoxyvasicinone (7) and harmane (8) were isolated as pure compounds by the CC. The structures of the five alkaloids 4, 5, 6, 7 and 8 were elucidated by the MS and 1H and 13C NMR analysis. The alkaloids 1, 2 and 8 were identified for the first time from this species.Mongolian Journal of Chemistry 16 (42), 2015, 48-53

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High resolution nuclear magnetic resonance spectroscopy of glycosphingolipids. I: 360 MHz 1H and 90.5 MHz 13C NMR analysis of galactosylceramides

Chemistry and Physics of Lipids ◽

10.1016/0009-3084(80)90006-7 ◽

1980 ◽

Vol 26 (2) ◽

pp. 187-196 ◽

Cited By ~ 55

Author(s):

Janusz Dabrowski ◽

Heinz Egge ◽

Peter Hanfland

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

High Resolution ◽

Magnetic Resonance Spectroscopy ◽

Nuclear Magnetic Resonance Spectroscopy ◽

13C Nmr ◽

Resonance Spectroscopy ◽

Nmr Analysis ◽

13C Nmr Analysis ◽

Nuclear Magnetic

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A New Oleanane Type Saponin from the Aerial Parts of Nigella sativa with Anti-Oxidant and Anti-Diabetic Potential

Molecules ◽

10.3390/molecules25092171 ◽

2020 ◽

Vol 25 (9) ◽

pp. 2171

Author(s):

Amna Parveen ◽

Muhammad Asim Farooq ◽

Whang Wan Kyunn

Keyword(s):

Nigella Sativa ◽

Tyrosine Phosphatase ◽

Resonance Spectroscopy ◽

Triterpenoid Saponin ◽

Aerial Parts ◽

Anti Oxidant ◽

Alternate Source ◽

Innovative Drugs ◽

New Compounds ◽

First Time

Natural product studies explore potential and interesting new compounds to discover innovative drugs. Nigella sativa (N. sativa) (Ranunculaceae) is traditionally used to treat diabetes. Flavonoids and triterpenoid mostly show anti-diabetic activity. The current study aim to identify new compounds by a systematic study of the anti-oxidant and anti-diabetic activity of aerial parts of N. sativa concerning. Phytochemicals were isolated from the methanolic extract of aerial parts of the plant by column chromatography and identified by nuclear magnetic resonance spectroscopy and mass spectroscopy. A new triterpenoid saponin glycoside was isolated along with flavonoids. The anti-diabetic study was carried out by DPPH, ABTS, α -glucosidase, and protein tyrosine phosphatase 1B assays at doses of 12.5 to 250 µM. The isolated phytochemicals were identified as 3-O-(β-d-xylopyranosyl-(1-3)-α-l-rhamnopyrnaosyl-(1-2)-α-l-arabinopyranosyl]-28-O-(α-l-rhamno-pyranosyl-(1-4)-β-d-glucopyranosyl-(1-6)-β-d-glucopyranosyl] hederagenin (1), flaccidoside III (2), catechol (3), quercetin-3-gentiobiosides (4), magnoflorine (5), nigelflavonoside B (6), nigelloside (7), quercetin sphorotrioside (8), kaempferol-3, 7-diglucoside (9), kaempferol 3-O-rutinoside (10), rutin (11), 3-O-[α-l-rhamnopyranosyl-(1→2)-α-l-arabinopyranpsylhederagenin (12), 3β,23,28-trihydroxyolean-12-ene-3-O-α-l-arabinopyranoside(1→4)-a-rhamnopyranosyl,(1→4)-β-d-gluco-pyranoside (13), 3-O-α-l-rhamnopyranosyl-(1→2)-α-l-arabinopyranpsyl]-28-O-β-d-gluco-pyranosyl hederagenin (14), and α-hederin (15). These were isolated and are reported for the first time in this study. Compared 13 was identified as a new compound. Compound 2 was isolated for first time from the genus Nigella. Compound 6 was found to be the most active in the DPPH, and ABTS assays and compound 10 was found to be the most active in the α-glucosidase assay, with IC50 32.7 ± 0.1, 95.18 ± 0.9, 214.5 ± 0.0 µΜ, respectively. Compound 12, at a dose of 125 µΜ, showed anti-diabetic activity in a PTP1B assay with IC50 91.30 ± 2.5 µΜ. In conclusion, the anti-diabetic activity of N. sativa is due to its flavonoids and TTSGs. Therefore, our studies suggest that the aerial parts of N. sativa are also a valuable and alternate source of valuable phytochemicals that could be used to develop anti-oxidant and anti-diabetic medicines.

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Properties of dissolved and total organic matter in throughfall, stemflow and forest floor leachate of Central European forests

Biogeosciences Discussions ◽

10.5194/bgd-11-15087-2014 ◽

2014 ◽

Vol 11 (10) ◽

pp. 15087-15107 ◽

Cited By ~ 1

Author(s):

S. Bischoff ◽

M. T. Schwarz ◽

J. Siemens ◽

L. Thieme ◽

W. Wilcke ◽

...

Keyword(s):

Organic Matter ◽

Tree Species ◽

Forest Floor ◽

Resonance Spectroscopy ◽

Total Organic Matter ◽

Allelopathic Potential ◽

Central European ◽

13C Nuclear Magnetic Resonance ◽

Structural Differences ◽

First Time

Abstract. For the first time, we investigated the composition of dissolved organic matter (DOM) compared to total OM (TOM, consisting of DOM and particulate OM, POM) in throughfall, stemflow and forest floor leachate of beech and spruce forests using solid state 13C nuclear magnetic resonance spectroscopy. We hypothesized that the composition and properties of OM in forest ecosystem water samples differed between DOM and TOM and between the two tree species. Under beech, a contribution of phyllosphere-derived fresh POM was echoed in structural differences. Compared with DOM, TOM exhibited higher relative intensities for the alkyl C region, representing aliphatic C from less decomposed organic material, and lower relative intensities for lignin-derived and aromatic C of the aryl C region, resulting in lower aromaticity indices and reduced humification intensities. Since differences in the structural composition of DOM and TOM were less pronounced under spruce than under beech, we suspect a~tree species-related effect on the origin of OM composition and resulting properties (e.g. recalcitrance, allelopathic potential).

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Metabolic engineering of Arabidopsis to produce nutritionally important DHA in seed oil

Functional Plant Biology ◽

10.1071/fp05084 ◽

2005 ◽

Vol 32 (6) ◽

pp. 473 ◽

Cited By ~ 102

Author(s):

Stan S. Robert ◽

Surinder P. Singh ◽

Xue-Rong Zhou ◽

James R. Petrie ◽

Susan I. Blackburn ◽

...

Keyword(s):

Seed Oil ◽

Land Plants ◽

Chain Elongation ◽

Seed Oils ◽

Omega 3 ◽

Fatty Acid Chain ◽

Genes Encoding ◽

Alternative Sources ◽

First Time ◽

Long Chain

Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are nutritionally important long-chain (≥ C20) omega-3 polyunsaturated fatty acids (ω3 LC-PUFA) currently obtained mainly from marine sources. A set of genes encoding the fatty acid chain elongation and desaturation enzymes required for the synthesis of LC-PUFA from their C18 PUFA precursors was expressed seed-specifically in Arabidopsis thaliana. This resulted in the synthesis of DHA, the most nutritionally important ω3 LC-PUFA, for the first time in seed oils, along with its precursor EPA and the ω6 LC-PUFA arachidonic acid (ARA). The assembled pathway utilised Δ5 and Δ6 desaturases that operate on acyl-CoA substrates and led to higher levels of synthesis of LC-PUFA than previously reported with acyl-PC desaturases. This demonstrates the potential for development of land plants as alternative sources of DHA and other LC-PUFA to meet the growing demand for these nutrients.

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Anti-Hepatocellular Carcinoma (HepG2) Activities of Monoterpene Hydroxy Lactones Isolated from the Marine Microalga Tisochrysis Lutea

Marine Drugs ◽

10.3390/md18110567 ◽

2020 ◽

Vol 18 (11) ◽

pp. 567

Author(s):

Katkam N. Gangadhar ◽

Maria João Rodrigues ◽

Hugo Pereira ◽

Helena Gaspar ◽

F. Xavier Malcata ◽

...

Keyword(s):

Hepg2 Cells ◽

Preparative Thin Layer Chromatography ◽

Omega 3 ◽

Nmr Analysis ◽

Tisochrysis Lutea ◽

Marine Microalga ◽

Bioassay Guided Fractionation ◽

First Time ◽

Layer Chromatography

Tisochrysis lutea is a marine haptophyte rich in omega-3 polyunsaturated fatty acids (e.g., docosahexaenoic acid (DHA)) and carotenoids (e.g., fucoxanthin). Because of the nutraceutical applications of these compounds, this microalga is being used in aquaculture to feed oyster and shrimp larvae. In our earlier report, T. lutea organic crude extracts exhibited in vitro cytotoxic activity against human hepatocarcinoma (HepG2) cells. However, so far, the compound(s) accountable for the observed bioactivity have not been identified. Therefore, the aim of this study was to isolate and identify the chemical component(s) responsible for the bioactivity observed. Bioassay-guided fractionation through a combination of silica-gel column chromatography, followed by preparative thin layer chromatography (PTLC), led to the isolation of two diastereomers of a monoterpenoid lactone, namely, loliolide (1) and epi-loliolide (2), isolated for the first time in this species. The structural elucidation of both compounds was carried out by GC-MS and 1D (1H and 13C APT) and 2D (COSY, HMBC, HSQC-ed, and NOESY) NMR analysis. Both compounds significantly reduced the viability of HepG2 cells and were considerably less toxic towards a non-tumoral murine stromal (S17) cell line, although epi-loliolide was found to be more active than loliolide.

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Superionic Lithium Intercalation through 2 nm x 2 nm Columns in the Crystallographic Shear Phase Nb18W8O69

10.26434/chemrxiv.11231153.v1 ◽

2019 ◽

Author(s):

Kent Griffith ◽

Clare Grey

Keyword(s):

High Performance ◽

Rate Capability ◽

Block Size ◽

Lithium Intercalation ◽

Resonance Spectroscopy ◽

Complex Metal Oxides ◽

Battery Electrode ◽

Crystallographic Shear ◽

Battery Material ◽

First Time

Nb18W8O69 (9Nb2O5×8WO3) is the tungsten-rich end-member of the Wadsley–Roth crystallographic shear (cs) structures within the Nb2O5–WO3 series. It has the largest block size of any known, stable Wadsley–Roth phase, comprising 5 ´ 5 units of corner-shared MO6 octahedra between the shear planes, giving rise to 2 nm ´ 2 nm blocks. Rapid lithium intercalation is observed in this new candidate battery material and 7Li pulsed field gradient nuclear magnetic resonance spectroscopy – measured in a battery electrode for the first time at room temperature – reveals superionic lithium conductivity. In addition to its promising rate capability, Nb18W8O69 adds a piece to the larger picture of our understanding of high-performance Wadsley–Roth complex metal oxides.

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Structure of a shear-thickening polysaccharide extracted from the New Zealand black tree fern, Cyathea medullaris

10.26686/wgtn.12597809.v1 ◽

2020 ◽

Author(s):

M Wee ◽

M Mastrangelo ◽

Susan Carnachan ◽

Ian Sims ◽

K Goh

Keyword(s):

New Zealand ◽

Uronic Acid ◽

Average Molecular Weight ◽

Shear Thickening ◽

Water Soluble ◽

Size Exclusion ◽

Resonance Spectroscopy ◽

Tree Fern ◽

13C Nuclear Magnetic Resonance ◽

Exclusion Chromatography

A shear-thickening water-soluble polysaccharide was purified from mucilage extracted from the fronds of the New Zealand black tree fern (Cyathea medullaris or 'mamaku' in Māori) and its structure characterised. Constituent sugar analysis by three complementary methods, combined with linkage analysis (of carboxyl reduced samples) and 1H and 13C nuclear magnetic resonance spectroscopy (NMR) revealed a glucuronomannan comprising a backbone of 4-linked methylesterified glucopyranosyl uronic acid and 2-linked mannopyranosyl residues, branched at O-3 of 45% and at both O-3 and O-4 of 53% of the mannopyranosyl residues with side chains likely comprising terminal xylopyranosyl, terminal galactopyranosyl, non-methylesterified terminal glucopyranosyl uronic acid and 3-linked glucopyranosyl uronic acid residues. The weight-average molecular weight of the purified polysaccharide was ~1.9×106Da as determined by size-exclusion chromatography coupled with multi-angle laser light scattering (SEC-MALLS). The distinctive rheological properties of this polysaccharide are discussed in relation to its structure. © 2014 Elsevier B.V.

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