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1.
Fitoterapia ; 153: 104995, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34293438

RESUMO

UDP-glycosyltransferases (UGTs) are an important and functionally diverse family of enzymes involved in secondary metabolite biosynthesis. Coumarin is one of the most common skeletons of natural products with candidate pharmacological activities. However, to date, many reported GTs from plants mainly recognized flavonoids as sugar acceptors. Only limited GTs could catalyze the glycosylation of coumarins. In this study, a new UGT was cloned from Cistanche tubulosa, a valuable traditional tonic Chinese herb, which is abundant with diverse glycosides such as phenylethanoid glycosides, lignan glycosides, and iridoid glycosides. Sequence alignment and phylogenetic analysis showed that CtUGT1 is phylogenetically distant from most of the reported flavonoid UGTs and adjacent to phenylpropanoid UGTs. Extensive in vitro enzyme assays found that although CtUGT1 was not involved in the biosynthesis of bioactive glycosides in C. tubulosa, it could catalyze the glucosylation of coumarins umbelliferone 1, esculetine 2, and hymecromone 3 in considerable yield. The glycosylated products were identified by comparison with the reference standards or NMR spectroscopy, and the results indicated that CtUGT1 can regiospecifically catalyze the glucosylation of hydroxyl coumarins at the C7-OH position. The key residues that determined CtUGT1's activity were further discussed based on homology modeling and molecular docking analyses. Combined with site-directed mutagenesis results, it was found that H19 played an irreplaceable role as the crucial catalysis basis. CtUGT1 could be used in the enzymatic preparation of bioactive coumarin glycosides.


Assuntos
Cistanche/enzimologia , Glicosiltransferases/química , China , Cistanche/genética , Clonagem Molecular , Cumarínicos , Glicosilação , Glicosiltransferases/genética , Simulação de Acoplamento Molecular , Estrutura Molecular , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Estrutura Secundária de Proteína , Especificidade por Substrato
2.
Sheng Wu Gong Cheng Xue Bao ; 37(6): 2077-2084, 2021 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-34227295

RESUMO

Curcumin is exclusively isolated from Zingiberaceae plants with a broad spectrum of bioactivities. In the present study, we used the diketide-CoA synthase (DCS) and curcumin synthase (CURS) genes to construct a non-natural fusion gene encoding diketide-CoA synthase::curcumin synthase (DCS::CURS). This fusion protein, together with the acetyl coenzyme A carboxylase (ACC) and the 4-coumarate coenzyme A ligase (4CL), were introduced into Escherichia coli for the production of curcumin from ferulic acid. The process is divided into two stages, the growth stage using LB medium and the fermentation stage using the modified M9 medium. The yield of curcumin reached 386.8 mg/L by optimizing the induction of protein expression in the growth stage, and optimizing the inoculum volume, medium composition and fermentation time in the fermentation stage, as well as the addition of macroporous resin AB-8 into the second medium to attenuate the toxicity of the end product. The exploitation of the non-natural fusion protein DCS::CURS for the production of curcumin provides a new alternative to further promoting the production of curcumin and the related analogues.


Assuntos
Curcumina , Escherichia coli , Curcumina/farmacologia , Escherichia coli/genética , Fermentação
3.
Org Lett ; 22(21): 8725-8729, 2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-33104367

RESUMO

Pelletierine, a proposed building block of Lycopodium alkaloids (LAs), was demonstrated to be synthesized via the non-enzymatic Mannich-like condensation of Δ1-piperideine and 3-oxoglutaric acid produced by two new type III PKSs (HsPKS4 and PcPKS1) characterized from Huperzia serrata and Phlegmariurus cryptomerianus, respectively. The findings provide new insights for further understanding the biosynthesis of LAs such as huperzine A.


Assuntos
Alcaloides/biossíntese , Lycopodium/metabolismo , Piperidinas/metabolismo , Alcaloides/química , Estereoisomerismo
4.
Nat Prod Res ; : 1-8, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32840396

RESUMO

Two new diterpenoids, penicichrysogene A (1) and penicichrysogene B (2), were isolated from the solid substrate fermentation cultures of Penicillium chrysogenum MT-12, an endophytic fungus isolated from the medicinal plant of Huperzia serrata. Their structures were elucidated on the basis of extensive spectroscopic and spectrometric data (1D and 2D NMR, UV, IR, and HRESIMS). The absolute configurations of 1 and 2 were assigned on the basis of experimental and calculated electronic circular dichroism spectra. Compound 1 exhibited inhibitory activity on ATP release of thrombin-activated platelets with IC50 = 42.7 ± 3.5 µM.

5.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3213-3220, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602874

RESUMO

A total of 27 endophytic fungal strains were isolated from Huperzia serrata,which were richly distributed in the stems and leaves while less distributed in roots. The 27 strains were identified by Internal Transcribed Spacer( ITS) r DNA molecular method and one of the strains belongs to Basidiomycota phylum,and other 26 stains belong to 26 species,9 general,6 families,5 orders,3 classes of Ascomycota Phylum. The dominant strains were Colletotrichum genus,belonging to Glomerellaceae family,Glomerellales order,Sordariomycetes class,Ascomycota Phylum,with the percentage of 48. 15%. The inhibitory activities of the crude extracts of 27 endophytic fungal strains against acetylcholinesterase( ACh E) and nitric oxide( NO) production were evaluated by Ellman's method and Griess method,respectively. Crude extracts of four fungi exhibited inhibitory activities against ACh E with an IC50 value of 42. 5-62. 4 mg·L~(-1),and some fungi's crude extracts were found to inhibit nitric oxide( NO) production in lipopolysaccharide( LPS)-activated RAW264. 7 macrophage cells with an IC50 value of 2. 2-51. 3 mg·L~(-1),which indicated that these fungi had potential anti-inflammatory activities.The chemical composition of the Et OAc extract of endophytic fungus HS21 was also analyzed by LCMS-IT-TOF. Seventeen compounds including six polyketides,four diphenyl ether derivatives and seven meroterpenoids were putatively identified.


Assuntos
Ascomicetos/química , Ascomicetos/classificação , Huperzia/microbiologia , Acetilcolinesterase , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Ascomicetos/isolamento & purificação , Inibidores da Colinesterase/isolamento & purificação , Inibidores da Colinesterase/metabolismo , Endófitos/classificação , Endófitos/isolamento & purificação , Camundongos , Células RAW 264.7
6.
Fitoterapia ; 137: 104282, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31381956

RESUMO

Four new polyketides, alternatains A-D (1-4), along with 17 known compounds (5-21) were obtained from the solid substrate fermentation cultures of Alternaria alternata MT-47, an endophytic fungus isolated from the medicinal plant of Huperzia serrata. Their structures were elucidated by extensive spectroscopic and spectrometric techniques (1D and 2D NMR, IR, and HRESIMS) and calculated electronic circular dichroism (ECD) method. Compounds 4, 6, 15, and 21 exhibited inhibitory activities on ATP release of thrombin-activated platelets with IC50 values in the range of 18.2-68.8 µM.


Assuntos
Alternaria/química , Anticoagulantes/farmacologia , Plaquetas/efeitos dos fármacos , Huperzia/microbiologia , Policetídeos/farmacologia , Acetilcolinesterase , Trifosfato de Adenosina , Anticoagulantes/isolamento & purificação , Butirilcolinesterase , China , Inibidores da Colinesterase , Endófitos/química , Humanos , Estrutura Molecular , Plantas Medicinais/microbiologia , Policetídeos/isolamento & purificação
7.
Molecules ; 24(15)2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31390736

RESUMO

Four new lignan glycosides; urenalignosides A-D (1-4), along with 12 known ones (5-16) were isolated from Urena lobata. Their structures were determined on the basis of extensive spectroscopic and spectrometric data (1D and 2D NMR; IR; CD; and HRESIMS). Compounds 2-4; 6; 7; 10; and 11 showed inhibition of nitric oxide production in lipopolysaccharide-induced RAW 264.7 macrophage cells with IC50 values in the range of 25.5-98.4 µM (positive control; quercetin; IC50 = 7.2 ± 0.2 µM).


Assuntos
Glicosídeos/química , Lignanas/química , Malvaceae/química , Extratos Vegetais/química , Animais , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Lignanas/isolamento & purificação , Lignanas/farmacologia , Espectroscopia de Ressonância Magnética , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Células RAW 264.7
8.
Fitoterapia ; 137: 104277, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31351127

RESUMO

Five new Lycopodium alkaloids, huperzine Y1 (1), huperzine Y2 (2), huperzine Y3 (3), (+)-huperzine Z (4a) and (-)-huperzine Z (4b) as well as ten known alkaloids (5-14) were isolated from Huperzia serrata. The structures of the new compounds were established using extensive spectroscopic (1D and 2D NMR, IR, and HRESIMS) and calculated electronic circular dichroism (ECD) methods. Compounds 4a and 4b were a pair of enantiomers successfully separated by chiral HPLC resolution. Compounds 2 and 3 indicated inhibitory activities against acetylcholinesterase with IC50 value of 57.1 ±â€¯1.6 and 32.7 ±â€¯1.0 µΜ, respectively. However, no compound showed inhibitory effect on butyrocholinesterase at the concentration of 100 µΜ.


Assuntos
Alcaloides/farmacologia , Huperzia/química , Acetilcolinesterase , Alcaloides/isolamento & purificação , Butirilcolinesterase , China , Inibidores da Colinesterase/isolamento & purificação , Inibidores da Colinesterase/farmacologia , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia
9.
J Nat Med ; 73(4): 769-776, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31209724

RESUMO

Six new pyrrole 2-carbaldehyde derived alkaloids, dahurines A-F (1-6), along with five known ones (7-11) and butyl 2-pyrrolidone-5-carboxylate (12) were isolated from the roots of Angelica dahurica. Their structures were determined by extensive spectroscopic and spectrometric data (1D and 2D NMR, IR, and HRESIMS) and calculated electronic circular dichroism (ECD) methods. Although compounds 7 and 8 have been chemically synthesized, they were obtained from natural materials for the first time. Compounds 2, 3, 4, 10, and 11 exhibited acetylcholinesterase inhibitory activity with IC50 values in the range of 47.5-52.5 µM. Pyrrole 2-carbaldehyde derived alkaloids from the roots of Angelica dahurica.


Assuntos
Alcaloides/química , Angelica/química , Inibidores da Colinesterase/farmacologia , Raízes de Plantas/química , Pirróis/farmacologia , Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/isolamento & purificação , Dicroísmo Circular , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Pirróis/isolamento & purificação
10.
Phytochemistry ; 158: 46-55, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30453219

RESUMO

Fifteen previously undescribed 2-(2-phenylethyl)chromone dimers, along with two known analogues were isolated from Chinese agarwood (Aquilaria sinensis) by a LC-MS-guided fractionation procedure. Their structures were elucidated on the basis of spectroscopic and spectrometric data (1D and 2D NMR, IR, and HRESIMS). The isolated compounds exhibited significant inhibition of nitric oxide production in lipopolysaccharide-stimulated RAW264.7 cells with IC50 values in the range 0.6-37.1 µM.


Assuntos
Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Cromonas/química , Thymelaeaceae/química , Animais , Anti-Inflamatórios não Esteroides/isolamento & purificação , Cromatografia Líquida , Cromonas/isolamento & purificação , Dimerização , Avaliação Pré-Clínica de Medicamentos/métodos , Concentração Inibidora 50 , Lipopolissacarídeos/farmacologia , Espectroscopia de Ressonância Magnética , Camundongos , Estrutura Molecular , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/metabolismo , Plantas Medicinais/química , Células RAW 264.7 , Espectrometria de Massas por Ionização por Electrospray
11.
Phytother Res ; 32(12): 2487-2500, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30306652

RESUMO

Although radix Salviae miltiorrhizae (RSM) is reported to exhibit the antiosteoporotic effect in preclinical study, the underlying mechanism is unclear. To this end, ovariectomized (OVX) rats were employed with administration of RSM (5 g/kg) for 14 weeks. The disturbed serum levels of alkaline phosphatase (ALP), osteoprotegerin (OPG), tartrate-resistant acid phosphatase, and receptor activator of nuclear factor-κB ligand (RANKL) in OVX rats were improved by RSM treatment. Furthermore, supplement of RSM to OVX rats resulted in an increase in femoral bone mineral density and bone strength as well as an improvement in bone microstructures. Moreover, the decreased expression of phosphor (p)-LRP6, insulin-like growth factor-1(IGF-1), ALP, and OPG, as well as increased expression of RANKL and cathepsin K in the tibias and femurs of OVX rats were shifted by RSM treatment. Additionally, RSM reversed the decreased ratio of p-glycogen synthase kinase 3ß (GSK3ß) to GSK3ß and increased ratio of p-ß-catenin to ß-catenin in OVX rats. Altogether, it is suggestive that RSM improves bone quantity and quality by favoring Wnt/ß-catenin and OPG/RANKL/cathepsin K signaling pathways in OVX rats thereby suggesting the potential of this herb to be a novel source of antiosteoporosis drugs.


Assuntos
Densidade Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Salvia miltiorrhiza/química , Animais , Osso e Ossos/ultraestrutura , Catepsina K/metabolismo , Feminino , Fêmur/efeitos dos fármacos , Fêmur/ultraestrutura , Resistência à Flexão/efeitos dos fármacos , NF-kappa B/metabolismo , Ovariectomia , Ligante RANK/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/metabolismo
12.
Org Lett ; 20(18): 5606-5609, 2018 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-30179018

RESUMO

By the genome-mining approach, a chimeric enzyme of prenyltransferase-diterpene synthase was discovered from Penicillium chrysogenum MT-12. Since its product exhibited broadened NMR signals, the structural determination by only the NMR analysis was difficult, but the crystalline sponge method successfully revealed the structure with a 6-5-5-5 fused ring system. This demonstrated that the collaboration between the genome-mining and crystalline sponge method has the potential to facilitate rapid inquiries into the unexplored chemical space of small molecules.

13.
Plant Sci ; 269: 1-11, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29606206

RESUMO

2-(2-Phenylethyl)chromones are the main compounds responsible for the quality of agarwood, which is widely used in traditional medicines, incenses and perfumes. H2O2 and NADPH oxidases (also known as respiratory burst oxidase homologs, Rbohs) mediate diverse physiological and biochemical processes in environmental stress responses. However, little is known about the function of H2O2 and NADPH oxidases in 2-(2-phenylethyl)chromones accumulation. In this study, we found that salt stress induced a transient increase in content of H2O2 and 2-(2-phenylethyl)chromones accumulation in Aquilaria sinensis calli. Exogenous H2O2 remarkably decreased the production of 2-(2-phenylethyl)chromones, while dimethylthiourea (DMTU), a scavenger of H2O2, significantly increased 2-(2-phenylethyl)chromones accumulation in salt treated calli. Three new H2O2-generating genes, named AsRbohA-C, were isolated and characterized from A. sinensis. Salt stress also induced a transient increase in AsRbohA-C expression and NADPH oxidase activity. Furthermore, exogenous H2O2 increased AsRbohA-C expression and NADPH oxidase activity, while DMTU inhibited AsRbohA-C expression and NADPH oxidase activity under salt stress. Moreover, diphenylene iodonium (DPI), the inhibitor of NADPH oxidases, reduced AsRbohA-C expression and NADPH oxidase activity, but significantly induced 2-(2-phenylethyl)chromones accumulation during salt stress. These results clearly demonstrated the central role of H2O2 and NADPH oxidases in regulation of salt-induced 2-(2-phenylethyl)chromones accumulation in A. sinensis calli.


Assuntos
Flavonoides/metabolismo , Peróxido de Hidrogênio/metabolismo , NADPH Oxidases/genética , Proteínas de Plantas/genética , Estresse Fisiológico , Thymelaeaceae/fisiologia , Sequência de Aminoácidos , NADPH Oxidases/química , NADPH Oxidases/metabolismo , Oniocompostos/farmacologia , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Alinhamento de Sequência , Cloreto de Sódio/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Tioureia/análogos & derivados , Tioureia/farmacologia , Thymelaeaceae/genética
14.
Fitoterapia ; 127: 123-128, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29447980

RESUMO

Five new megastigmane glycosides, urenalobasides A-E (1-5), together with 11 known ones (6-16) were isolated from Urena lobata. Their structures were determined by extensive spectroscopic and spectrometric data (1D and 2D NMR, IR, and HRESIMS) and calculated electronic circular dichroism method. Compounds 1 and 2 are two unusual megastigmanes structurally containing a 6/5 fused ring system. Compound 3 exhibits inhibition of nitric oxide production in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells with IC50 value of 53.7 ±â€¯1.0 µM (positive control, dexamethasone, IC50 = 16.6 ±â€¯0.8 µM).


Assuntos
Cicloexanonas/isolamento & purificação , Glucosídeos/isolamento & purificação , Glicosídeos/isolamento & purificação , Malvaceae/química , Norisoprenoides/isolamento & purificação , Animais , Camundongos , Estrutura Molecular , Óxido Nítrico/metabolismo , Células RAW 264.7
15.
J Nat Prod ; 81(3): 543-553, 2018 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-29227647

RESUMO

Sixteen new 2-(2-phenylethyl)chromone dimers, including four pairs of enantiomers (1a/1b, 3a/3b, 6a/6b, and 8a/8b), along with eight optically pure analogues (2, 4, 5, 7, and 9-12) were isolated from the resinous wood of Aquilaria sinensis. Their structures were determined by extensive spectroscopic analysis (1D and 2D NMR, UV, IR, and HRMS) and experimental and computed ECD data. Compounds 1-10 feature an unusual 3,4-dihydro-2 H-pyran ring linkage connecting two 2-(2-phenylethyl)chromone monomeric units, while compounds 11 and 12 possess an unprecedented 6,7-dihydro-5 H-1,4-dioxepine moiety in their structures. A putative biosynthetic pathway of the representative structures via a diepoxy derivative of a chromone with a nonoxygenated A-ring is also proposed. Compounds 1a/1b, 2, 3a/3b, 5, 7, 8a/8b, and 10-12 exhibited significant inhibition of nitric oxide production in lipopolysaccharide-stimulated RAW264.7 cells with IC50 values in the range 7.0-12.0 µM.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Thymelaeaceae/química , Madeira/química , Animais , Linhagem Celular , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Lipopolissacarídeos/farmacologia , Espectroscopia de Ressonância Magnética/métodos , Camundongos , Óxido Nítrico/metabolismo , Células RAW 264.7 , Resinas Vegetais/química , Resinas Vegetais/farmacologia
16.
Zhongguo Zhong Yao Za Zhi ; 42(17): 3305-3311, 2017 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-29192439

RESUMO

The MYB gene family comprises one of the richest groups of transcription factors in plants. The full length of two MYB genes were isolated through heterologous screening of Aquilaria sinensis calli transcriptome data, and the reverse transcription PCR was performed to obstain the corrected MYB clones, named AsMYB1, AsMYB2. The MYB transmembrane domain and phylogenetic analysis were predicted by different software to analyze the bioinformatics of MYB proteins. The transcript level of AsMYB1, AsMYB2 was performed by real-time quantitative RT-PCR in different tissues and in responds to abiotic stresses including salt, cold, metal and drought stress, and hormone treatments including abscisic acid (ABA), salicylic acid (SA), gibberellins (GA3) and methyl jasmonate (MeJA) treatment. The AsMYB1 cDNA sequence had an ORF of 1 063 nucleotides, encoding a protein of 353 amino acids. The largest AsMYB2 ORF was 1 081 nucleotides, and its predicted translation products consisted of 359 amino acids. Two MYB genes had a tissues-specific pattern in A. sinensis. Moreover, the expression level of AsMYB1 and AsMYB2 was regulated by different abiotic stresses and hormone treatments, suggesting the transcription factors AsMYB1 and AsMYB2 play an important role in plant defense and hormone signal transduction in A. sinensis.


Assuntos
Proteínas de Plantas/genética , Estresse Fisiológico , Thymelaeaceae/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Fases de Leitura Aberta , Filogenia
17.
Fitoterapia ; 123: 35-43, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28958955

RESUMO

Twelve new polyketides, penicichrysogenins A-L (1-10, 11a, and 11b) along with five known compounds (12a, 12b, and 13-15) were isolated from the solid substrate fermentation cultures of a Huperzia serrata endophytic fungus Penicillium chrysogenum MT-12. The structures of the new compounds were established using extensive spectroscopic (1D and 2D NMR, IR, and HRESIMS) and calculated electronic circular dichroism (ECD) methods. Compounds 11a/11b and 12a/12b were two pairs of enantiomers successfully separated by chiral HPLC resolution. Compounds 4, 5, 8, 9, 11a/11b, and 12a/12b exhibited inhibition of nitric oxide production in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells with IC50 values in the range of 17.5-98.4µM.


Assuntos
Huperzia/microbiologia , Óxido Nítrico/metabolismo , Penicillium chrysogenum/química , Policetídeos/química , Animais , Camundongos , Estrutura Molecular , Policetídeos/isolamento & purificação , Células RAW 264.7
18.
J Nat Prod ; 80(10): 2699-2707, 2017 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-28960979

RESUMO

Eight new chrysogenolides (A-H (1-8)) and seven known (9-15) 3,5-dimethylorsellinic acid derived meroterpenoids were isolated from the solid substrate fermentation cultures of a Huperzia serrata endophytic fungus, Penicillium chrysogenum MT-12. The structures of the new compounds were elucidated by interpretation of spectroscopic and spectrometric data (1D and 2D NMR, IR, and HRESIMS). The absolute configurations of 1-4 were determined by single-crystal X-ray crystallographic analysis, and those of 5-8 were assigned on the basis of experimental and calculated electronic circular dichroism spectra. Compounds 3, 4, 6, 11, and 12 showed inhibition of nitric oxide production in lipopolysaccharide-activated RAW 264.7 macrophage cells with IC50 values in the range of 4.3-78.2 µM (positive control, indomethacin, IC50 = 33.6 ± 1.4 µM).


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Huperzia/microbiologia , Penicillium chrysogenum/química , Resorcinóis/isolamento & purificação , Animais , Cristalografia por Raios X , Medicamentos de Ervas Chinesas/química , Concentração Inibidora 50 , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Conformação Molecular , Estrutura Molecular , Óxido Nítrico/biossíntese , Ressonância Magnética Nuclear Biomolecular , Resorcinóis/química
19.
Biochem Biophys Res Commun ; 486(4): 1040-1047, 2017 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-28366630

RESUMO

Type III polyketide synthases (PKSs) play an important role in biosynthesis of various plant secondary metabolites and plant adaptation to environmental stresses. Aquilaria sinensis (A. sinensis) is the main plant species for production of agarwood, little is known about its PKS family. In this study, AsCHS1 and two new type III PKSs, AsPKS1 and AsPKS2, were isolated and characterized in A. sinensis calli. The comparative sequence and phylogenetic analysis indicated that AsPKS1 and AsPKS2 belonged to non-CHS group different from AsCHS1. The recombinant AsPKS1 and AsPKS2 produced the lactone-type products, suggesting their different enzyme activities from AsCHS1. Three PKS genes had a tissues-specific pattern in A. sinensis. Moreover, we examined the expression profiles of three PKS genes in calli under different abiotic stresses and hormone treatments. AsCHS1 transcript was most significantly induced by salt stress, AsPKS1 abundance was most remarkably enhanced by CdCl2 treatment, while AsPKS2 expression was most significantly induced by mannitol treatment. Furthermore, AsCHS1, AsPKS1 and AsPKS2 expression was enhanced upon gibberellins (GA3), methyl jasmonate (MeJA), or salicylic acid (SA) treatment, while three PKS genes displayed low transcript levels at the early stage under abscisic acid (ABA) treatment. In addition, three GFP:PKSs fusion proteins were localized in the cytoplasm and cell wall in Nicotiana benthamiana cells. These results indicated the multifunctional role of three type III PKSs in polyketide biosynthesis, plant resistance to abiotic stresses and signal transduction.


Assuntos
Aciltransferases/química , Aciltransferases/fisiologia , Lactonas/química , Estresse Fisiológico/fisiologia , Frações Subcelulares/metabolismo , Thymelaeaceae/enzimologia , Catálise , Proteínas de Plantas/química , Proteínas de Plantas/fisiologia , Relação Estrutura-Atividade , Thymelaeaceae/classificação , Thymelaeaceae/citologia , Distribuição Tecidual
20.
Fitoterapia ; 118: 49-55, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28237880

RESUMO

Five new 2-(2-phenylethyl)chromone derivatives (1-5), along with eleven known compounds (6-16) were isolated from Chinese agarwood. Their structures were elucidated by spectroscopic data (NMR, UV, IR, and MS) analyses and comparison of their spectroscopic and physical data with the literature values. The absolute configurations of 2-4 were determined by electronic circular dichroism (ECD) calculations. Compounds 2-4, 11, 12, and 15 exhibited significant inhibition of nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 cells with IC50 values in the range 1.6-7.3µM.


Assuntos
Anti-Inflamatórios/química , Flavonoides/química , Thymelaeaceae/química , Animais , Anti-Inflamatórios/isolamento & purificação , Flavonoides/isolamento & purificação , Camundongos , Estrutura Molecular , Óxido Nítrico/metabolismo , Células RAW 264.7 , Madeira/química
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