scholarly journals Isolation, Structural Characterization, and Valorization of Pectic Substances from Algerian Argan Tree Leaves (Argania spinosa(L.) Skeels)

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Kadda Hachem ◽  
Abderrahmane Labani ◽  
Meriem Kaid-Harche

Pectic polysaccharides were solubilized from Algerian argan tree leaves by sequential extraction with water at 100°C (water-soluble pectin; AL-WSP) and EDTA solution at 80°C (chelating-soluble pectin; AL-CSP). Both AL-WSP and AL-CSP were rich in arabinose (28% and 74.5%, resp.) and had a high content of uronic acid (38.5% and 21.5%, resp.). Pectic substances were deesterified and fractionated by anion exchange chromatography, giving five fractions for each extract. Most of the fractions were characterized by methylation analysis and then analyzed by13C nuclear magnetic resonance spectroscopy. The results showed that AL-WSP consisted of rhamnogalacturonan type I, with arabinan and galactan branching at the O-4 position of the main rhamnose chain, while AL-CSP consisted of rhamnogalacturonan type I and a block of homogalacturonan. Antioxidant activities of AL-WSP and AL-CSP were evaluated by electronic spin resonance. The results showed that the antioxidant potential of AL-WSP (8.1%) and AL-CSP (−1.2%) was significantly lower than that of vitamin E.

1998 ◽  
Vol 64 (9) ◽  
pp. 3175-3179 ◽  
Author(s):  
Benny Chefetz ◽  
Yona Chen ◽  
Yitzhak Hadar

ABSTRACT Chaetomium thermophilium was isolated from composting municipal solid waste during the thermophilic stage of the process.C. thermophilium, a cellulolytic fungus, exhibited laccase activity when it was grown at 45°C both in solid media and in liquid media. Laccase activity reached a peak after 24 h in liquid shake culture. Laccase was purified by ultrafiltration, anion-exchange chromatography, and affinity chromatography. The purified enzyme was identified as a glycoprotein with a molecular mass of 77 kDa and an isoelectric point of 5.1. The laccase was stable for 1 h at 70°C and had half-lives of 24 and 12 h at 40 and 50°C, respectively. The enzyme was stable at pH 5 to 10, and the optimum pH for enzyme activity was 6. The purified laccase efficiently catalyzed a wide range of phenolic substrates but not tyrosine. The highest levels of affinity were the levels of affinity to syringaldazine and hydroxyquinone. The UV-visible light spectrum of the purified laccase had a peak at 604 nm (i.e., Cu type I), and the activity was strongly inhibited by Cu-chelating agents. When the hydrophobic acid fraction (the humic fraction of the water-soluble organic matter obtained from municipal solid waste compost) was added to a reaction assay mixture containing laccase and guaiacol, polymerization took place and a soluble polymer was formed. C. thermophilium laccase, which is produced during the thermophilic stage of composting, can remain active for a long period of time at high temperatures and alkaline pH values, and we suggest that this enzyme is involved in the humification process during composting.


Author(s):  
Ken-ji Yokoi ◽  
Sosyu Tsutsui ◽  
Gen-ya Arakawa ◽  
Masakazu Takaba ◽  
Koichi Fujii ◽  
...  

Abstract Information about the inulosucrase of non-lactic acid bacteria is scarce. We found a gene encoding inulosucrase (inuBK) in the genome of the gram-positive bacterium Alkalihalobacillus krulwichiae JCM 11691. The inuBK open reading frame encoded a protein comprising 456 amino acids. We expressed His-tagged InuBK in culture medium using a Brevibacillus system. The optimal pH and temperature of purified InuBK were 7.0–9.0 and 50 °C–55 °C, respectively. The findings of high-performance anion-exchange chromatography, nuclear magnetic resonance spectroscopy, and high-performance size-exclusion chromatography with multi-angle laser light scattering showed that the polysaccharide produced by InuBK was an inulin with a molecular weight of 3,806, a polydispersity index (PI) of 1.047, and fructosyl chain lengths with 3–27 degrees of polymerization. The size of InuBK was smaller than commercial inulins, and the PI of the inulin that it produced was lower.


1990 ◽  
Vol 269 (2) ◽  
pp. 393-402 ◽  
Author(s):  
P Ryden ◽  
R R Selvendran

1. Polymers were solubilized from the cell walls of parenchyma from mature runner-bean pods with minimum degradation by successive extractions with cyclohexane-trans-1,2-diamine-NNN′N′-tetra-acetate (CDTA), Na2CO3 and KOH to leave the alpha-cellulose residue, which contained cross-linked pectic polysaccharides and Hyp-rich glycoproteins. These were solubilized with chlorite/acetic acid and cellulase. The polymers were fractionated by anion-exchange chromatography, and fractions were subjected to methylation analysis. 2. The pectic polysaccharides differed in their ease of extraction, and a small proportion were highly cross-linked. The bulk of the pectic polysaccharides solubilized by CDTA and Na2CO3 were less branched than those solubilized by KOH. There was good evidence that most of the pectic polysaccharides were not degraded during extraction. 3. The protein-containing fractions included Hyp-rich and Hyp-poor glycoproteins associated with easily extractable pectic polysaccharides, Hyp-rich glycoproteins solubilized with 4M-KOH+borate, the bulk of which were not associated with pectic polysaccharides, and highly cross-linked Hyp-rich glycoproteins. 4. Isodityrosine was not detected, suggesting that it does not have a (major) cross-linking role in these walls. Instead, it is suggested that phenolics, presumably linked to C-5 of 3,5-linked Araf residues of Hyp-rich glycoproteins, serve to cross-link some of the polymers. 5. There were two main types of xyloglucan, with different degrees of branching. The bulk of the less branched xyloglucans were solubilized by more-concentrated alkali. The anomeric configurations of the sugars in one of the highly branched xyloglucans were determined by 13C-n.m.r. spectroscopy. 6. The structural features of the cell-wall polymers and complexes are discussed in relation to the structure of the cell walls of parenchyma tissues.


Holzforschung ◽  
2004 ◽  
Vol 58 (1) ◽  
pp. 97-104 ◽  
Author(s):  
B. Saake ◽  
S. Lebioda ◽  
J. Puls

Abstract Four methyl cellulose samples in the degree of substitution range from 0.5 to 2.0 were characterised by combination of different analytical methods. Samples were analysed regarding their partial degree of substitution by hydrolysis and anion exchange chromatography with pulsed amperometric detection. For calibration of the chromatographic system, standard substances were isolated by preparative HPLC and their structure was confirmed by 13C-NMR spectroscopy. For two methyl cellulose samples per-acetylation and 13C-NMR with inverse gated decoupling was carried out for comparison with the chromatographic analysis. Endoglucanase fragmentation of methyl celluloses was performed and water-soluble and insoluble fractions were analysed separately. A preparative size exclusion chromatography system for enzymatic-degraded water-soluble methyl cellulose was developed and the molar masses of the individual fractions were examined by analytical size exclusion chromatography. By combination of endoglucanase fragmentation, preparative chromatography, hydrolysis and anion exchange chromatography an approach for the analysis of the substitutent distribution along the polymeric chain of water-soluble methyl cellulose could be established.


1987 ◽  
Vol 247 (1) ◽  
pp. 165-174 ◽  
Author(s):  
M Whitman ◽  
D Kaplan ◽  
T Roberts ◽  
L Cantley

Phosphatidylinositol (PtdIns) kinase activities from non-transformed and polyoma-middle-T-transformed murine fibroblasts were examined. Both normal and transformed 3T3 fibroblasts have two PtdIns kinases, which can be separated by anion-exchange chromatography. One of these activities (Type I) has a Km for ATP of 10 microM, is resistant to inhibition by adenosine, AMP or ADP, and is inhibited by non-ionic detergents. The other activity (Type II) has a somewhat higher Km for ATP (35 microM) and is inhibited competitively by ADP, AMP and adenosine at concentrations suggesting regulation of this activity by the energy charge of the cell. The Type II PtdIns kinase is activated by non-ionic detergents. We have previously reported the specific association of a PtdIns kinase activity with polyoma-middle-T immunoprecipitates [Whitman, Kaplan, Schaffhausen, Cantley & Roberts (1985) Nature (London) 315, 239-242; Kaplan, Whitman, Schaffhausen, Raptis, Garcea, Pallas, Roberts & Cantley (1986) Proc. Natl. Acad. Sci. U.S.A. 83, 3624-3628]. Comparison of the immunoprecipitated PtdIns kinase with the activities identified by ion-exchange chromatography indicates that it is the Type I enzyme which specifically associates with the middle-T/pp60c-src complex. This PtdIns kinase activity is separable from both middle T and pp60c-src. Type I PtdIns kinase also associates with pp60v-src immunoprecipitates from Rous-sarcoma-virus-transformed cells. Furthermore, this PtdIns kinase appears to co-precipitate with partially purified platelet derived growth factor (PDGF) receptor. The amount of this activity found in anti-phosphotyrosine immunoprecipitates or in wheat-germ-lectin-agarose precipitates is increased 50-fold by stimulation of quiescent Balb/C 3T3 fibroblasts with PDGF. These results suggest that the Type I PtdIns kinase is regulated by agents which affect cell growth and transformation, whereas the Type II PtdIns kinase may be regulated by the local [ATP]/[ADP] ratio.


2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Pai-Feng Kao ◽  
Shwu-Huey Wang ◽  
Wei-Ting Hung ◽  
Yu-Han Liao ◽  
Chun-Mao Lin ◽  
...  

The major cell wall constituent ofGanoderma lucidum(G. lucidum) isβ-1,3-glucan. This study examined the polysaccharide from the residues of alkaline-extracted fruiting bodies using high-performance anion-exchange chromatography (HPAEC), and it employed nuclear magnetic resonance (NMR) and mass spectrometry (MS) to confirm the structures. We have successfully isolated low-molecular-weightβ-1,3-glucan (LMG), in high yields, from the waste residue of extracted fruiting bodies ofG. lucidum. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay evaluated the capability of LMG to suppress H2O2-induced cell death in RAW264.7 cells, identifying that LMG protected cells from H2O2-induced damage. LMG treatment decreased H2O2-induced intracellular reactive oxygen species (ROS) production. LMG also influenced sphingomyelinase (SMase) activity, stimulated by cell death to induce ceramide formation, and then increase cell ROS production. Estimation of the activities of neutral and acid SMasesin vitroshowed that LMG suppressed the activities of both neutral and acid SMases in a concentration-dependent manner. These results suggest that LMG, a water-solubleβ-1,3-glucan recycled from extracted residue ofG. lucidum, possesses antioxidant capability against H2O2-induced cell death by attenuating intracellular ROS and inhibiting SMase activity.


1986 ◽  
Vol 238 (2) ◽  
pp. 491-499 ◽  
Author(s):  
S Palmer ◽  
P T Hawkins ◽  
R H Michell ◽  
C J Kirk

When hepatocytes were incubated with [32P]Pi, the kinetics for the labelling of the monoester phosphate groups of phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate were similar to each other and slightly slower than that for the labelling of the gamma-phosphate of ATP. Analysis of the water-soluble 3H-labelled materials derived from [3H]inositol-labelled hepatocytes revealed that, in addition to inositol and its mono-, bis- and tris-phosphates (Ins, InsP, InsP2 and InsP3), these cells contained two unidentified radioactive compounds which co-eluted with InsP on anion-exchange chromatography. When [3H]inositol-labelled hepatocytes were stimulated with 0.23 microM-vasopressin in the presence of 10 mM-Li+, there was an accumulation of radioactivity in InsP, InsP2 and InsP3 but not in Ins or the two unidentified compounds. Further analysis of these inositol phosphates by h.p.l.c. revealed that vasopressin also stimulates the accumulation of inositol tetrakisphosphate (InsP4) in these cells. Vasopressin-stimulated InsP and InsP2 accumulations were maximal in the presence of 1-10 mM-Li+ but InsP3 accumulation continued to increase up to 50 mM-Li+. Accumulated inositol phosphates were retained within the cell. Li+ from 1 to 50 mM did not influence the extent of vasopressin-stimulated inositol lipid degradation in hepatocytes. In the absence of Li+, radioactivity in vasopressin-stimulated hepatocytes accumulated almost entirely in free inositol. The vasopressin-stimulated accumulation of inositol phosphates in the presence of 10 mM-Li+ was abolished by a V1-vasopressin antagonist. Inositol phosphate accumulation was not influenced by ionophore A23187, dimethyl sulphoxide or indomethacin.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Hai-Yang Yu ◽  
Dong-Mei Gao ◽  
Wei Zhou ◽  
Bing-Bing Xia ◽  
Zhi-Yuan He ◽  
...  

Abstract Introduction Ovine interferon-tau (oIFN-τ) is a newly discovered type I interferon. This study used biochemical techniques to transform the oIFN-τ gene into Escherichia coli to obtain the mass and soluble expression of the recombinant protein. Materials and Methods First, total RNA was extracted from fresh sheep embryonic tissues with TRIzol reagent and then used as a template to reverse transcribe and amplify the mature oIFN-τ gene with RT-PCR. The amplified product was next digested with the HindIII and XhoI restriction enzymes and inserted into the pET-32a(+) vector to construct the prokaryotic expression plasmid. The corrected in-frame recombinant plasmid, pET-32a(+)-oIFN-τ, was transformed into E. coli Rosetta (DE3) competent cells. After induction with isopropyl-beta-D-thiogalactopyranoside (IPTG), the recombinant protein was detected in bacteria. Finally, the bacteria were lysed by sonication, and the recombinant protein was purified by nickel affinity chromatography and DEAE anion exchange chromatography. Results The protein was confirmed to be oIFN-τ, which mainly existed in the soluble lysate fraction, as proven by SDS-PAGE and Western blot assays. Conclusion Purified IFN-τ exists mostly in a soluble form, and its anti-vesicular stomatitis virus (VSV) activity reached 7.08×10(6)IU/mL.


Polymers ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 255
Author(s):  
Roman Bleha ◽  
Lucie Třešnáková ◽  
Leonid Sushytskyi ◽  
Peter Capek ◽  
Jana Čopíková ◽  
...  

In this study, we focused on the isolation and structural characterization of polysaccharides from a basidiocarp of polypore fungus Ganoderma resinaceum. Polysaccharide fractions were obtained by successive extractions with cold water at room temperature (20 °C), hot water under reflux (100 °C), and a solution of 1 mol L−1 sodium hydroxide. The purity of all fractions was controlled mainly by Fourier transform infrared (FTIR) spectroscopy, and their composition and structure were characterized by organic elemental analysis; neutral sugar and methylation analyses by gas chromatography equipped with flame ionization detector (GC/FID) and mass spectrometry detector (GC/MS), respectively; and by correlation nuclear magnetic resonance (NMR) spectroscopy. The aqueous extracts contained two main polysaccharides identified as a branched O-2-β-d-mannosyl-(1→6)-α-d-galactan and a highly branched (1→3)(1→4)(1→6)-β-d-glucan. Mannogalactan predominated in the cold water extract, and β-d-glucan was the main product of the hot water extract. The hot water soluble fraction was further separated by preparative anion exchange chromatography into three sub-fractions; two of them were identified as branched β-d-glucans with a structure similar to the corresponding polysaccharide of the original fraction. The alkaline extract contained a linear (1→3)-α-d-glucan and a weakly branched (1→3)-β-d-glucan having terminal β-d-glucosyl residues attached to O-6 of the backbone. The insoluble part after all extractions was identified as a polysaccharide complex containing chitin and β-d-glucans.


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