scholarly journals HSQC-NMR analysis of lignin in woody (Eucalyptus globulus and Picea abies) and non-woody (Agave sisalana) ball-milled plant materials at the gel state 10th EWLP, Stockholm, Sweden, August 25–28, 2008

Holzforschung ◽  
2009 ◽  
Vol 63 (6) ◽  
Author(s):  
Jorge Rencoret ◽  
Gisela Marques ◽  
Ana Gutiérrez ◽  
Lidia Nieto ◽  
J. Ignacio Santos ◽  
...  
Keyword(s):  
Picea Abies ◽  
Eucalyptus Globulus ◽  
2D Nmr ◽  
Structural Features ◽  
Rapid Screening ◽  
Nmr Analysis ◽  
Plant Materials ◽  
General Terms ◽  
Whole Plant ◽  
Agave Sisalana

Abstract In situ analysis of lignin by 2D NMR of whole plant material was carried out by swelling finely ball-milled samples in deuterated dimethylsulfoxide (DMSO-d6 ) and sonicated so that a gel was formed in the NMR analysis tube. Solution HSQC NMR spectra of different plant materials representative for hardwood (Eucalyptus globulus), softwood (Picea abies), and non-woody plants (Agave sisalana) are presented here. The spectra show signals corresponding to those of the main plant constituents, such as lignin and polysaccharides. The lignin signals were assigned by comparing the HSQC spectra of the whole plant materials with the HSQC spectra of their respective milled-wood lignins (MWLs). In general terms, the major lignin structural features, such as the relative abundances of the main lignin substructures, the syringyl/guaiacyl ratios and the extent of γ-acetylation of the lignin side-chain observed in the HSQC spectra of the whole plant materials, matched those obtained from the HSQC spectra of the isolated MWLs. Therefore, this technique, which needs only minor amounts of lignocellulosic material and minimal sample preparation, can be useful for the rapid screening of plant lignins without the need for tedious and time-consuming lignin isolation procedures.

Characterization of non-cellulosic glucans in Eucalyptus globulus Labill. wood and kraft pulp

Holzforschung ◽  
2007 ◽  
Vol 61 (5) ◽  
pp. 478-482 ◽  
Author(s):  
Sara A. Lisboa ◽  
Dmitry V. Evtuguin ◽  
Carlos Pascoal Neto
Keyword(s):  
Eucalyptus Globulus ◽  
Fiber Surface ◽  
2D Nmr ◽  
Structural Features ◽  
Kraft Pulping ◽  
Hot Water ◽  
Pulp Yield ◽  
Naoh Solution ◽  
Nmr Techniques

Abstract The amount of non-cellulosic glucans in Eucalyptus globulus wood (approx. 4.5%) was assessed by extraction of sawdust with a 0.5 M NaOH solution at 90–120°C and the structural features were elucidated in a glucan-enriched polysaccharide fraction isolated by hot water extraction (120°C, 2 h). Isolated soluble glucans were characterized by wet chemistry methods and a set of 1D and 2D NMR techniques. The major proportion of glucans consisted of amylose (20%) and amylopectin (80%), although a small proportion of β-(1→3)-glucan (<0.2% on wood weight) was also detected. Although glucans are easily removed in the initial phase of kraft pulping, notable amounts were found in unbleached pulp and it was supposed that in the final stage of kraft pulping a fraction of α-glucan is precipitated onto the fiber surface and contributes to the pulp yield.

Rarely Occurring Natural Products Isolated from Vincetoxicum stocksii

2019 ◽  
Vol 41 (4) ◽  
pp. 695-695
Author(s):  
Saima Khan Saima Khan ◽  
Muhammad Imran Tousif Muhammad Imran Tousif ◽  
Naheed Raiz Naheed Raiz ◽  
Mamona Nazir Mamona Nazir ◽  
Mahreen Mukhtar Mahreen Mukhtar ◽  
...  
Keyword(s):  
Natural Products ◽  
Methanol Extract ◽  
High Resolution Mass Spectrometry ◽  
Ethyl Acetate Fraction ◽  
2D Nmr ◽  
Ethyl Carbamate ◽  
Carbamic Acid ◽  
Nmr Analysis ◽  
Nmr Techniques ◽  
Resolution Mass

Silica gel column chromatography of the ethyl acetate fraction of methanol extract of Vincetoxicum stocksii resulted in the separation of three new rarely occurring natural products; [4-(4-(methoxycarbonyl)benzyl)phenyl] carbamic acid (1), bis[di-p-phenylmethane]ethyl carbamate (2), methyl 2-hydroxy-3-(2-hydroxy-5-(3-methylbut-2-enyl)phenyl)-2-(4-hydroxyphenyl) propanoate, stocksiloate(3), along with five known compounds; 1-(4-hydroxy-3-methoxyphenyl)-1,2,3,-propanetriol (4), feruloyl-6-O-β-D-glucopyranoside (5), 4-hydroxy-3,5-dimethoxybenzoic acid (6), apocynin (7) and vincetomine (8). The structures of compounds 1 and 2 were established with help of 1D, 2D-NMR techniques and high resolution mass spectrometry, whereas, compound 3 could only be characterized tentatively by 1D, 2D-NMR techniques. Compounds 1 is new compound while 2 is synthetically known but never been reported from natural source. The known compounds were identified due to 1D NMR analysis and in comparison with the literature values. Compounds 1-3 were found inactive in an anti-urease assay.

Two Ceramides from Tanacetum artemesioides

2004 ◽  
Vol 59 (3) ◽  
pp. 329-333 ◽  
Author(s):  
Viqar U. Ahmad ◽  
Javid Hussain ◽  
Hidayat Hussain ◽  
Umar Farooq ◽  
Erum Akber ◽  
...  
Keyword(s):  
Inhibitory Activity ◽  
Structure Elucidation ◽  
2D Nmr ◽  
Nmr Analysis ◽  
New Compounds

Two new ceramides have been isolated from Tanacetum artemisioides, besides the known constituents β -sitosterol and β -sitosterol glycoside. The structure elucidation of the isolated new compounds was based primarily on 1D and 2D NMR analysis, including COSY, HMQC, HMBC correlations. The compound 1 and 2 showed inhibitory activity against acetylcholinesterase

Trimethylsilylation - Aid in NMR Analysis of Oligosaccharides. Assigment of29Si and13C NMR Spectra of Trimethylsilylated Methyl β-D-Xylobiosides by 2D NMR

1985 ◽  
Vol 4 (3) ◽  
pp. 393-403 ◽  
Author(s):  
Jan Schramla ◽  
Eva Petráková ◽  
Jan Pelnař ◽  
Magdalena Kvíačlova ◽  
Václav Chvalovský
Keyword(s):  
Nmr Spectra ◽  
2D Nmr ◽  
Nmr Analysis

Structural characterization of milled wood lignins from different eucalypt species

Holzforschung ◽  
2008 ◽  
Vol 62 (5) ◽  
Author(s):  
Jorge Rencoret ◽  
Gisela Marques ◽  
Ana Gutiérrez ◽  
David Ibarra ◽  
Jiebing Li ◽  
...  
Keyword(s):  
Eucalyptus Globulus ◽  
Chemical Structure ◽  
2D Nmr ◽  
Analytical Pyrolysis ◽  
Additional Information ◽  
Diaryl Ether ◽  
Heteronuclear Single Quantum Correlation ◽  
Relative Abundances ◽  
Type 3

Abstract The chemical structure of milled-wood lignins from Eucalyptus globulus, E. nitens, E. maidenii, E. grandis, and E. dunnii was investigated. The lignins were characterized by analytical pyrolysis, thioacidolysis, and 2D-NMR that confirmed the predominance of syringyl over guaiacyl units and only showed traces of p-hydroxyphenyl units. E. globulus lignin had the highest syringyl content. The heteronuclear single quantum correlation (HSQC) NMR spectra yielded information about relative abundances of inter-unit linkages in the whole polymer. All the lignins showed a predominance of β-O-4′ ether linkages (66–72% of total side-chains), followed by β-β′ resinol-type linkages (16–19%) and lower amounts of β-5′ phenylcoumaran-type (3–7%) and β-1′ spirodienone-type linkages (1–4%). The analysis of desulfurated thioacidolysis dimers provided additional information on the relative abundances of the various carbon-carbon and diaryl ether bonds, and the type of units (syringyl or guaiacyl) involved in each of the above linkage types. Interestingly, 93–94% of the total β-β′ dimers included two syringyl units indicating that most of the β-β′ substructures identified in the HSQC spectra were of the syringaresinol type. Moreover, three isomers of a major trimeric compound were found which were tentatively identified as arising from a β-β′ syringaresinol substructure attached to a guaiacyl unit through a 4-O-5′ linkage.

scholarly journals Labdane and Abietane Diterpenoids from Juniperus oblonga and Their Cytotoxic Activity

Molecules ◽  
2019 ◽  
Vol 24 (8) ◽  
pp. 1561 ◽  
Author(s):  
Qiao ◽  
Khutsishvili ◽  
Alizade ◽  
Atha ◽  
Borris
Keyword(s):  
Cell Lines ◽  
Human Tumor ◽  
2D Nmr ◽  
Human Tumor Cell Lines ◽  
Abietane Diterpenoids ◽  
Whole Plant ◽  
Phytochemical Investigation ◽  
Ic50 Values ◽  
First Time ◽  
Mcf 7

A phytochemical investigation of the whole plant of Juniperus oblonga led to the isolationof one previously undescribed labdane diterpenoid, (4R,5S,9S,10R)‐13‐des‐ethyl‐13‐oxolabda‐8(17),11E‐dien‐19‐oic acid (1), together with nine known diterpenoids (2–3, 6–12), two lignans (4, 5),and a coumarin (13). The structures of all the compounds were elucidated on the basis ofspectrometric data, primarily one‐dimensional (1D)‐ and two‐dimensional (2D)‐NMR and massspectrometry. Electronic circular dichroism (ECD) calculations determined the absoluteconfiguration of 1. In addition, the isolated compounds were evaluated for their cytotoxic activityagainst three human tumor cell lines (HepG2, MCF‐7, and HeLa). 6,12‐Dihydroxyabieta‐5,8,11,13‐tetraen‐7‐one (6) showed moderate cytotoxicity against all three cell lines with IC50 values rangingfrom 24.41 μM to 58.39 μM and trilobinone (10) showed weaker activity with IC50 values rangingfrom 56.93 μM to 79.98 μM. None of the isolated diterpenoids have been previously reported fromJuniperus oblonga, and five compounds are here reported from the genus Juniperus for the first time.

scholarly journals Meliloester, a New Melilotic Ester from Melilotus alba

2012 ◽  
Vol 7 (1) ◽  
pp. 1934578X1200700
Author(s):  
Rasheeda Khatoon ◽  
Nikhat Saba ◽  
Aqib Zahoor ◽  
Shazia Summer ◽  
Viqar Uddin Ahmad
Keyword(s):  
2D Nmr ◽  
Spectroscopic Studies ◽  
Mass Spectrometric ◽  
Melilotus Alba ◽  
Ethyl Hexyl ◽  
Whole Plant

A new melilotic ester, meliloester [2-ethyl-hexyl-3-(2-hydroxyphenyl) propionate], was isolated from the whole plant of Melilotus alba. Its structure was elucidated on the basis of spectroscopic and mass spectrometric analyses, including EI-MS, HR-MS, and UV, IR, 1D and 2D -NMR spectroscopic studies.

scholarly journals In vitro digestion of galactolipids from chloroplast-rich fraction (CRF) of postharvest, pea vine field residue (haulm) and spinach leaves

2019 ◽  
Vol 10 (12) ◽  
pp. 7806-7817 ◽  
Author(s):  
Jutarat Wattanakul ◽  
Moulay Sahaka ◽  
Sawsan Amara ◽  
Syamila Mansor ◽  
Brigitte Gontero ◽  
...  
Keyword(s):  
Pancreatic Juice ◽  
In Vitro Digestion ◽  
Plant Materials ◽  
Whole Plant ◽  
Spinach Leaves

The galactolipase activity of pancreatic juice, pancreatic extracts and a purified PLRP2 (GPLRP2) on chloroplast-rich fractions from whole plant materials under in vitro condition was measured.

scholarly journals Ellagitannins from Geranium potentillaefolium and G. bellum

2010 ◽  
Vol 5 (4) ◽  
pp. 1934578X1000500
Author(s):  
Juan A. Gayosso-De-Lucio ◽  
J. Martín Torres-Valencia ◽  
Carlos M. Cerda-García-Rojas ◽  
Pedro Joseph-Nathan
Keyword(s):  
Nmr Spectroscopy ◽  
Gallic Acid ◽  
Ellagic Acid ◽  
Therapeutic Dose ◽  
2D Nmr ◽  
Published Data ◽  
Methyl Gallate ◽  
2D Nmr Spectroscopy ◽  
Plant Materials ◽  
Aerial Parts

The aerial parts of Geranium potentillaefoium afforded geraniin (1), corilagin (2), gallic acid (4), methyl gallate (6), methyl brevifolincarboxylate (7), quercetin, quercetin 3- O-β-D-glucopyranoside, quercetin 3- O-β-D-[6″- O-galloyl)glucopyranoside, kaempferol, β-sitosterol 3- O-β-D-glucopyranoside and β-sitosterol, while the aerial parts of G. bellum gave the same compounds in addition to kaempferol 3- O-β-D-glucopyranoside, isolated instead of kaempferol. The substances were identified by 1D and 2D NMR spectroscopy in comparison with published data. The water decoction preparations from air-dried plant materials (2.5 g) contain ca. 4.6 % of the ellagitannin 1, envisaging that when such decoction is ingested (250 mL), a therapeutic dose of ca. 36 mg of the antitumor ellagic acid (3) may be incorporated into the organism.

scholarly journals Two New Prenylated Isoflavonoids from Erinacea anthyllis with Antioxidant and Antibacterial Activities

2017 ◽  
Vol 12 (7) ◽  
pp. 1934578X1701200 ◽  
Author(s):  
Soumia Mouffouk ◽  
Laurence Marcourt ◽  
Mohammed Benkhaled ◽  
Kaouthar Boudiaf ◽  
Jean-Luc Wolfender ◽  
...  
Keyword(s):  
Antioxidant Activities ◽  
Optical Rotation ◽  
2D Nmr ◽  
Antibacterial Activities ◽  
Total Phenolic ◽  
Aerial Parts ◽  
Whole Plant ◽  
The Family ◽  
Chemotaxonomic Markers ◽  
Phenolic And Flavonoid

Two new prenylated isoflavonoids, namely Erinasone A and Erinasone B along with 19 known secondary metabolites, including twelve isoflavonoids, three polyphenols, one flavonol, two flavanones and three steroids, were isolated from the whole plant (roots and aerial parts) of Erinacea anthyllis. Structures of all isolated compounds were elucidated by spectroscopic analysis, including 1D and 2D NMR (1H, 13C, COSY, HSQC, TOCSY, HMBC and NOESY), mass spectrometry (ESI-MS), UV-Vis, measurement of optical rotation [α]D and by comparison with the literature data. The total phenolic and flavonoid contents were determined in this study. Furthermore, the antioxidant and antibacterial activities of the EtOAc and n-BuOH extracts of E. anthyllis were evaluated. These extracts exhibited moderate antibacterial and antioxidant activities. Their IC50 values were approximately 0.04 mg/mL ( n-BuOH) and 0.037 mg/mL (EtOAc). Consequently, Erinacea anthyllis is a rich source of polyphenolic compounds particularly isoflavonoids used as chemotaxonomic markers for the subfamily Papilionoideae of the family Fabaceae.

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