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1.
Int J Biol Macromol ; 271(Pt 2): 132234, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38763239

RÉSUMÉ

Lignin, a renewable natural antioxidant and bacteriostat, holds promise as a versatile, cost-effective feed additive. However, traditional industrial lignin faces limitations, including low reactivity, poor uniformity, and unstable properties, necessitating chemical modification. Complex modification methods pose economic and toxicity challenges, so this study adopted a relatively simple alkali-catalyzed phenolization approach, using phenol, catechol, and pyrogallol to modify kraft lignin, and characterized the resulting products using various techniques. Subsequently, their antioxidant, antibacterial, adsorption properties for heavy metal ions and mycotoxins, growth-promoting properties, and antiviral abilities were assessed. The phenolation process led to lignin depolymerization and a notable increase in phenolic hydroxyl content, particularly in pyrogallol-phenolated lignin (Py-L), rising from 3.08 to 4.68 mmol/g. These modified lignins exhibited enhanced antioxidant activity, with over 99 % inhibition against E. coli and S. aureus, and remarkable adsorption capacities for heavy metal ions and mycotoxins. Importantly, Py-L improved the growth performance of mice and reduced influenza mortality. Furthermore, density functional theory calculations elucidated the mechanism behind the enhanced antioxidant properties. This study presents a promising avenue for developing versatile feed additives to address challenges related to animal feed antioxidant supplementation, bacterial control, and growth promotion.


Sujet(s)
Aliment pour animaux , Antioxydants , Lignine , Lignine/composition chimique , Antioxydants/composition chimique , Antioxydants/pharmacologie , Animaux , Souris , Antibactériens/pharmacologie , Antibactériens/composition chimique , Escherichia coli/effets des médicaments et des substances chimiques , Escherichia coli/croissance et développement , Phénols/composition chimique , Phénols/pharmacologie , Staphylococcus aureus/effets des médicaments et des substances chimiques , Adsorption , Pyrogallol/composition chimique , Pyrogallol/pharmacologie , Métaux lourds/composition chimique , Mycotoxines/composition chimique , Mycotoxines/pharmacologie
2.
Phytomedicine ; 21(4): 515-22, 2014 Mar 15.
Article de Anglais | MEDLINE | ID: mdl-24252332

RÉSUMÉ

Ginsenoside F(2) (F(2)) is a potential bioactive metabolite of major ginsenosides. The potential anti-cancer effect of F(2) in gastric cancer cells has not been appraised. This study investigated the effects of F(2) on the production of reactive oxygen species (ROS). We also investigated the in vitro and in vivo effects of F(2) on the downstream signaling pathways leading to apoptosis in human gastric cancer cells. The in vitro data revealed that F(2) induces ROS accumulation followed by a decrease in mitochondrial transmembrane potential (MTP), and the release of cytochrome c (cyto c), which induced the caspase-dependent apoptosis. Further assay indicated that modulation of ASK-1/JNK pathway contributes to apoptosis. In vivo, F(2) exhibits the obvious anti-cancer effect compared with cisplatin with no obvious toxicity. Jointly, these results suggest that F(2) induces apoptosis by causing an accumulation of ROS and activating the ASK-1/JNK signaling pathway. This provides further support for the use of F(2) as a novel anticancer therapeutic candidate.


Sujet(s)
Carcinomes/traitement médicamenteux , Ginsénosides/usage thérapeutique , Potentiel de membrane mitochondriale/effets des médicaments et des substances chimiques , Espèces réactives de l'oxygène/métabolisme , Tumeurs de l'estomac/traitement médicamenteux , Apoptose/effets des médicaments et des substances chimiques , Carcinomes/métabolisme , Lignée cellulaire tumorale , Tests de criblage d'agents antitumoraux , Ginsénosides/pharmacologie , Humains , MAP Kinase Kinase Kinase 5/métabolisme , Système de signalisation des MAP kinases/effets des médicaments et des substances chimiques , Tumeurs de l'estomac/métabolisme
3.
J Pharm Biomed Anal ; 59: 67-77, 2012 Feb 05.
Article de Anglais | MEDLINE | ID: mdl-22047761

RÉSUMÉ

A method coupling high-performance liquid chromatography (HPLC) with quadrupole time-of-flight mass spectrometers (QTOF-MS) using an eletrospray ionization (ESI) source was firstly developed for detection, characterization and guiding target separation of variants of protopanaxdiol saponin from leaves of Panax notoginseng. Under the guidance of LC-QTOF-MS, a new trace saponin was probed according to the precise elemental compositions of molecular ions and the fragmentation behavior, and then separated from the ethanol extract of the plant by a set of chromatographic methods. It was further confirmed by NMR experiments as 3-O-ß-D-glucopyranoside-3ß,l2ß,23ß-triol-20-ene-dammar (Pn-1). The cytotoxic assay showed that Pn-1 had relatively stronger anti-tumor effects against three tumor cell lines (NCI-H460, HepG2 and SGC-7901) than Rg3, an approved clinical agent for cancer therapy. Meanwhile, based on accurate mass measurements within 5 ppm for each molecular ions and subsequent product ions, 48 saponins, including 40 protopanaxadiol saponins, 7 protopanaxatriol saponins and 1 oleanane saponin were identified. It is noted that the knowledge of the presence of abundant protopanaxadiol saponins in leaves of P. notoginseng may provide tools for a full understanding of the chemical diversity of secondary metabolites from the different parts of P. notoginseng. From the points of time consuming and accurate mass measurement capability, the LC-QTOF-MS is a highly powerful tool for screening and guiding target separation of new compounds in herbal extract, and thus benefits the speed of new drug discovery progress.


Sujet(s)
Antinéoplasiques d'origine végétale/isolement et purification , Panax notoginseng/composition chimique , Panax notoginseng/métabolisme , Saponines/isolement et purification , Antinéoplasiques d'origine végétale/composition chimique , Antinéoplasiques d'origine végétale/pharmacologie , Lignée cellulaire tumorale , Survie cellulaire/effets des médicaments et des substances chimiques , Chromatographie en phase liquide à haute performance , Humains , Structure moléculaire , Feuilles de plante/composition chimique , Feuilles de plante/métabolisme , Saponines/composition chimique , Saponines/pharmacologie , Spectrométrie de masse ESI
4.
Mar Drugs ; 9(2): 162-183, 2011 Jan 28.
Article de Anglais | MEDLINE | ID: mdl-21566793

RÉSUMÉ

Six new sterols (1-6), together with seven known sterols (7-13), were isolated from the CCl(4) extract of the marine bryozoan Cryptosula pallasiana, four (3-6) of which have already been reported as synthetic sterols. This is the first time that these compounds (3-6) are reported as natural sterols. The structures of the new compounds were determined on the basis of the extensive spectroscopic analysis, including two-dimensional (2D) NMR and HR-ESI-MS data. Compounds 1-4, 7 and 10-13 were evaluated for their cytotoxicity against HL-60 human myeloid leukemia cell line, and all of the evaluated compounds exhibited moderate cytotoxicity to HL-60 cells with a range of IC(50) values from 14.73 to 22.11 µg/mL except for compounds 12 and 13.


Sujet(s)
Antinéoplasiques/composition chimique , Antinéoplasiques/pharmacologie , Bryozoa/composition chimique , Stérols/composition chimique , Stérols/pharmacologie , Animaux , Antinéoplasiques/isolement et purification , Lignée cellulaire tumorale , Tests de criblage d'agents antitumoraux , Cellules HL-60 , Humains , Leucémie myéloïde/traitement médicamenteux , Spectroscopie par résonance magnétique/méthodes , Stérols/isolement et purification , Cellules U937
6.
Planta Med ; 77(13): 1550-4, 2011 Sep.
Article de Anglais | MEDLINE | ID: mdl-21347998

RÉSUMÉ

Two new oleanane-type triterpenoid saponins, 1 and 2, and a new natural product, 3, together with five known saponins, 4- 8, were isolated from the rhizomes of ANEMONE TAIPAIENSIS. Their structures were elucidated by extensive spectroscopic analysis and chemical evidences. Six saponins, 1, 2, 4- 7, which possessed a free carboxylic group at C-28, exhibited significant cytotoxicity against human leukemia HL-60 cells and human hepatocellular carcinoma Hep-G2 cells with IC (50) values in the range of 1.31-10.12 µM.


Sujet(s)
Anemone/composition chimique , Antinéoplasiques d'origine végétale/pharmacologie , Extraits de plantes/composition chimique , Rhizome/composition chimique , Saponines/pharmacologie , Antinéoplasiques d'origine végétale/composition chimique , Lignée cellulaire tumorale , Survie cellulaire , Humains , Structure moléculaire , Acide oléanolique/analogues et dérivés , Acide oléanolique/composition chimique , Acide oléanolique/pharmacologie , Saponines/composition chimique
7.
Bing Du Xue Bao ; 24(5): 340-4, 2008 Sep.
Article de Chinois | MEDLINE | ID: mdl-19035321

RÉSUMÉ

Two H5N1 avian influenza viruses (AIV), A/mallard/Huadong/S/2005 (S, IVPI = 2.65, in mallard) and A/mallard/Huadong/Y/2003 (Y, IVPI = 0, in mallard), were capable of distinct in pathogenicity to non-immunized mallards (Anas platyrhynchos). There were two amino acid residues difference in the HA cleavage site between two viruses, 322 (S, Leu; Y, Gln) and 329 (S, deletion; Y, Lys). Based on the variation, a series of recombinant viruses carrying HA gene either from S or Y virus with mutation at 322 and/or 329 were constructed via reverse genetics system to explore the influence of the two amino acid residues on viral pathogenicity in mallards. Recombinant viruses with S virus backbone were completely attenuated in terms of their virulence to ducks when position 322 (L322Q) and/or position 329 (-329K) of HA gene had been mutated. The critical role that L322 and -329 of HA protein from S virus play in the high virulence to ducks were influenced by the entire background of that protein because the recombinant virus with HA gene from Y and other seven genes from S were completely attenuated even if Q322L and K329- mutations of HA gene had been achieved. Recombinant viruses with Y virus backbone significantly increased their virulence to ducks when position 322 (Q322L) and/or position 329 (K329-) of HA gene had been mutated. All recombinant viruses carrying HA gene from Y with Q322L and/or K329-mutations and other seven genes from S were completely attenuated in terms of virulence to ducks whereas all recombinant viruses carrying HA gene from Y with same mutations and other seven genes from Y gained significant virulence. It seems that the compatibility among eight genes might be an important factor for HA to exert its functions. Results indicated that the mutation at amino acid position 322 and deletion at 329 in HA cleavage site significantly influence the pathogenicity of S and Y viruses in mallard, the compatibility among eight genes also contribute to the pathogenicity of both viruses in mallard.


Sujet(s)
Glycoprotéine hémagglutinine du virus influenza/composition chimique , Sous-type H5N1 du virus de la grippe A/pathogénicité , Animaux , Oiseaux , Glycoprotéine hémagglutinine du virus influenza/génétique , Glycoprotéine hémagglutinine du virus influenza/physiologie , Sous-type H5N1 du virus de la grippe A/génétique , Relation structure-activité , Virulence
8.
Wei Sheng Wu Xue Bao ; 45(4): 491-5, 2005 Aug.
Article de Chinois | MEDLINE | ID: mdl-16245856

RÉSUMÉ

Several H6 subtype avian A influenza viruses were isolated from aquatic birds in some live bird markets when we surveyed the ecology of the influenza in East China for more than two years and identified by specific RT-PCR. In this paper, the hemagglutinin (HA) and neuraminidase (NA) gene of one representative virus named A/Duck/Yangzhou/233/ 2002 (H6N2) (Dk/YZ/233/02) had been sequenced. Phylogenetic analysis of the H6 gene sequences available in the Influenza Sequence Database showed that the Dk/YZ/233/02 viruse cluster together with Dk/HK/3461/99 (H6N1) and Ck/Taiwan/na3/98 (H6N1). Phylogenetic analysis of the N2 NA genes of Dk/YZ/233/02 revealed that the NA gene of Dk/YZ/233/02 had genetically close relationships with that of H9N2 viruses isolated from duck in Japan and from chickens in South Korea, which were distinct from those of Ck/Beijing/94 (H9N2). The sequence of cleavage site between HA1 and HA2 of Dk/YZ/233/02 is P-Q-I-E-T-R-D, which was the typical characterization of the LPAIV.


Sujet(s)
Glycoprotéine hémagglutinine du virus influenza/génétique , Virus de la grippe A/classification , Grippe chez les oiseaux/virologie , Sialidase/génétique , Animaux , Poulets , Glycoprotéine hémagglutinine du virus influenza/composition chimique , Virus de la grippe A/génétique , Phylogenèse
9.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 20(6): 702-4, 2004 Nov.
Article de Chinois | MEDLINE | ID: mdl-15555440

RÉSUMÉ

AIM: To prepare monoclonal antibodies (mAb) against the hemagglutinin(HA) of H9 subtype of avian influenza virus (AIV). METHODS: 8 week-old female BALB/c mice were immunized with the inactivated vaccine of H9 subtype of AIV. Splenocytes from the immunized mice were fused with Sp2/0 myeloma cells, and positive hybridoma clones were screened by indirect ELISA and hemagglutination inhibition test (HI). The specificity of the mAb was characterized by ELISA, HI test, indirect immunofluorescence (IF) staining and Western blot. RESULTS: Three hybridoma cell lines named 2H1, 2A3 and 1C8 against HA of AIV H9 were obtained. The HI titers of 3 mAbs were 1 x 2(8)-1 x 2(13), and the ELISA titers were 1 x 10(-7), 1 x 10(-5) and 5 x 10(-6), respectively. The immunoglobulin subclass of all 3 mAbs was IgG1. Western blot analysis confirmed that mAb 2H1 could recognize HA and reacted to 31 out of 32 isolates of H9 subtype of AIV. CONCLUSION: Three mAbs recognizing HA of H9 subtype of AIV were obtained, which may provide an useful tool for the antigenic analysis, the serological diagnosis, the epidemiological survey and the evaluation of AIV vaccine.


Sujet(s)
Anticorps monoclonaux/biosynthèse , Anticorps antiviraux/biosynthèse , Antigènes viraux/immunologie , Glycoprotéine hémagglutinine du virus influenza/immunologie , Virus de la grippe A/immunologie , Animaux , Anticorps monoclonaux/immunologie , Anticorps antiviraux/immunologie , Spécificité des anticorps , Femelle , Hybridomes/immunologie , Hybridomes/métabolisme , Immunoglobuline G/analyse , Virus de la grippe A/classification , Souris , Souris de lignée BALB C
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