共查询到20条相似文献,搜索用时 27 毫秒
1.
A series of nalidixic acid‐based hydrazones have been synthesized and evaluated for their in vitro antimicrobial activity using the broth microdilution method against a panel of reference strains of microorganisms, including Gram‐positive bacteria, Gram‐negative bacteria, and fungi belonging to yeasts Candida spp. and molds Aspergillus spp., Penicillium spp., and Rhizopus spp. Nalidixic acid derivatives were obtained by condensation reaction of nalidixic acid hydrazide with substituted (hetero)aromatic aldehydes. All compounds have been characterized by 1H NMR and 13C NMR spectra. The antimicrobial activity indicated that compound with indole substituent could be a promising lead for future development of active antifungal agents. 相似文献
2.
A biotechnological process involving filamentous fungi to produce natural crystalline vanillin from maize bran 总被引:6,自引:0,他引:6
Lesage-Meessen L Lomascolo A Bonnin E Thibault JF Buleon A Roller M Asther M Record E Ceccaldi BC Asther M 《Applied biochemistry and biotechnology》2002,102(1-6):141-153
A new process involving the filamentous fungi Aspergillus niger and Pycnoporus cinnabarinus has been designed for the release of ferulic acid by enzymic degradation of a cheap and natural agricultural byproduct (autoclaved
maize bran) and its biotransformation into vanillic acid and/or vanillin with a limited number of steps. On the one hand,
the potentialities of A. niger I-1472 to produce high levels of polysaccharide-degrading enzymes including feruloyl esterases and to transform ferulic acid
into vanillic acid were successfully combined for the release of free ferulic acid from autoclaved maize bran. Then vanillic
acid was recovered and efficiently transformed into vanillin by P. cinnabarinus MUCL 39533, since 767 mg/L of biotechnologic vanillin could be produced in the presence of cellobiose and XAD-2 resin. On
the other hand, 3-d-old high-density cultures of P. cinnabarinus MUCL39533 could be fed with the autoclaved fraction of maize bran as a ferulic acid source and a. niger I-1472 culture filtrate as an extracellular enzyme source. Under these conditions, P. cinnabarinus MUCL39533 was shown to directly biotransform free ferulic acid released from the autoclaved maize bran by A. niger I-1472 enzymes into 584 mg/L of vanillin. These processes, involving physical, enzymic, and fungal treatments, permitted
us to produce crystallin vanillin from autoclaved maize bran without any purification step. 相似文献
3.
André F. Torres Paulo A. R. Mesquita Francisco M. Campos José A. Couto Ildikó V. Tóth António O. S. S. Rangel Timothy A. Hogg 《Mikrochimica acta》2007,159(1-2):87-93
A flow injection analysis (FIA) system was developed for the determination of phosphate efflux from wine lactic acid bacteria
(Oenococus oeni and Lactobacillus hilgardii) as an indication of cell membrane damage. The system allowed the direct injection of the cell suspension, avoiding the filtration
step, with minimum sample treatment and minimized reagent consumption. The developed system is characterized by a linear concentration
zone between 3.23 × 10−5 and 4.84 × 10−4 mol L−1 PO4
3− and repeatability better than 2.9%. Bacterial suspensions were exposed to a chemical stress with phenolic acids and injected
in the FIA system at regular intervals. The extracellular concentration of phosphate was measured spectrophotometrically.
The experimental results obtained indicate that hydroxycinnamic acids (p-coumaric, ferulic and caffeic) induced faster phosphate leakage rates than hydroxybenzoic acids (vanillic and p-hydroxybenzoic) in both strains tested, which could be related to their higher lipophilic character. 相似文献
4.
A. J. McCarthy E. A. Peace A. Paterson Paul Broda 《Applied biochemistry and biotechnology》1984,9(4):383-383
A collection of actinomycetes including fresh isolates was initially screened for the ability to degrade ball-milled straw
or utilize lignin-related aromatic compounds. Selected strains were tested for ligninolytic activity by measuring the amount
of14CO2 released from [14C-lignin] wheat lignocellulose. Two actinomycetes,Thermomonospom mesophila and aStreptomyces sp., were particularly effective, degrading up to 8% of the radiolabeled substrate to14CO2 in 10 d at 37‡C.14CO2 evolution was not significantly affected by flushing flasks with air rather than 100% O2, or growing the actinomycetes in shake-flask rather than stationary broth cultures. Solubilization of radioactivity paralleled14CO2 evolution and was greatest during the first 72 h of growth, after which no further increase in water-soluble14C was detected although14CO2 evolution continued at a reduced rate. The regulation of ligninolytic activity in these actinomycetes thus differs from that
in white-rot fungi, and HPLC analyses of the degradation products suggest that their mode of attack on grass lignin is distinct.
Xylanolytic strains from four thermophilic actinomycete taxa were also obtained. These strains produced inducible extracellular
xylanases that were active over a broad pH and temperature range and were relatively thermostable. TLC analysis suggested
that endoxylanases were the predominant components and gel electrophoresis provided further information on the nature of the
xylanase complex. The activity of these enzymes against native lignocellulose was also studied.
We thank the Agricultural Research Council and the British Petroleum Venture Research Unit for support. 相似文献
5.
Sabrina Belaïd Anne Landreau Safia Djebbar Ouassini Benali-Baïtich Mustayeen A. Khan Gilles Bouet 《Transition Metal Chemistry》2008,33(4):511-516
The synthesis and characterisation by elemental analysis, conductivity, FTIR, UV–Visible, ESR and magnetic measurements are
described for a series of complexes of nickel(II) and cobalt(II) with three ligands (H2L1–3) derived from reduced N, N′-o-Phenylenebis(salicylideneimine). The complexes formed are identified as neutral species, where the ligands are coordinated
through N and O donor atoms. The formulae obtained for the complexes are: [CoL(H2O)2] with octahedral geometry and [NiL] with tetrahedral geometry. Their antifungal activity is evaluated towards human pathogenic
fungi including yeasts of the Candida genus, some opportunistic moulds belonging to the Aspergillus, Scedosporium genus and some dermatophytes. The cobalt complexes show a significant growth inhibition of yeasts tested and also to fungi of the
genus Scedosporium which is of interest because these fungi are usually poorly susceptible to current antifungal including Amphotericin B and
Itraconazole, chosen as reference in this study. The activity data show that the metal complexes are more potent than the
parent ligand. 相似文献
6.
Macchione MM Merheb CW Gomes E da Silva R 《Applied biochemistry and biotechnology》2008,146(1-3):223-230
A comparative study was carried out to evaluate protease production in solid-state fermentation (SSF) and submerged fermentation
(SmF) by nine different thermophilic fungi – Thermoascus aurantiacus Miehe, Thermomyces lanuginosus, T. lanuginosus TO.03, Aspergillus flavus 1.2, Aspergillus sp. 13.33, Aspergillus sp. 13.34, Aspergillus sp. 13.35, Rhizomucor pusillus 13.36 and Rhizomucor sp. 13.37 – using substrates containing proteins to induce enzyme secretion. Soybean extract (soybean milk), soybean flour,
milk powder, rice, and wheat bran were tested. The most satisfactory results were obtained when using wheat bran in SSF. The
fungi that stood out in SSF were T. lanuginosus, T. lanuginosus TO.03, Aspergillus sp. 13.34, Aspergillus sp. 13.35, and Rhizomucor sp. 13.37, and those in SmF were T. aurantiacus, T. lanuginosus TO.03, and 13.37. In both fermentation systems, A. flavus 1.2 and R. pusillus 13.36 presented the lowest levels of proteolytic activity. 相似文献
7.
Donata Iandolo Alessandra Piscitelli Giovanni Sannia Vincenza Faraco 《Applied biochemistry and biotechnology》2011,163(1):40-51
A process of solid state fermentation (SSF) on tomato pomace was developed with the white-rot fungi Pleurotus ostreatus and Trametes versicolor, using sorghum stalks as support. Operative parameters (humidity, water activity, and size of substrate particles) guaranteeing
a good colonization of tomato pomace by both fungi were defined and conditions for production at high titers of the industrially
relevant enzymes laccase, xylanase and protease were identified. Significant laccase activity levels (up to 36 U g−1 dry matter) were achieved without any optimization of culture conditions, neither by nutrient addition nor by O2 enrichment. Furthermore, protease activity levels up to 34,000 U g−1 dry matter were achieved, being higher than those reported for the fungi typically considered as the best protease producers
such as Aspergillus strains. Moreover, as one of the most significant results of this study, analysis of P. ostreatus tomato SSF samples by zymogram revealed two bands with laccase activity which had not been detected so far. 相似文献
8.
Duralí Mendíl Ahmet Bílgín Yaşar Gök H. Basrí Şentük 《Journal of inclusion phenomena and macrocyclic chemistry》2002,43(3-4):265-270
A new N,N'-substituted diaminoglyoxime (H
2
L) containing a diazatetraoxamacrobicycle [2.2.2B] has been synthesized from an aromatic primary amine attached to the cryptand moiety and cyanogen-di-N-oxide. The BF2
+-capped Co(III) and heterotri-nuclear complexes of thevic-dioxime were prepared. The new compounds werecharacterized by a combination of elemental analysis and 1H NMR,13C NMR, IR and MS spectral data. 相似文献
9.
The microbial transformations of peucedanin and oreoselon by the fungi Aspergillus niger and Aspergillus sp. were investigated for the first time. Incubation of peucedanin with A. niger yielded a new hydroxylated metabolite with high yield (56%), which was characterized as 2-(1-hydroxypropan-2-yl)-3-methoxy-7H-furo[3,2-g]chromen-7-one. Oreoselon was converted to a new reduced metabolite methyl 3-(2,3-dihydro-6-hydroxy-2-isopropyl-3-oxobenzofuran-5-yl)propanoate in biotransformation by Aspergillus sp. The structures of the metabolites were determined by spectroscopic methods including IR, EI-MS, 1H NMR, 13C NMR, and elemental analysis. 相似文献
10.
Abstract
Direct reductive amination of 1,3-diphenyl-1H-pyrazole-4-carbaldehyde and 3-(4-methylphenyl)-1-phenyl-1H-pyrazole-4-carbaldehyde with various substituted aromatic amines using NaBH4 in the presence of I2 as reducing agent is described. The reaction has been carried out in anhydrous methanol under neutral conditions at room temperature. The structure of newly synthesized diphenyl pyrazolylmethylanilines was established on the basis of IR, 1H, 13C NMR, and mass spectral data. All diphenyl pyrazolylmethylaniline derivatives were tested in vitro for their antifungal and antibacterial activity against different strains of fungi and bacteria. Most of the compound exhibited considerable antifungal activity but poor antibacterial activity against the test strains. 相似文献11.
Matejícek D Klejdus B Mikes O Sterbová D Kubán V 《Analytical and bioanalytical chemistry》2003,377(2):340-345
A fast, selective and sensitive chromatographic method has been developed for determination of gallic, protocatechuic, p-hydroxybenzoic, vanillic, caffeic, syringic, p-coumaric, benzoic, ferulic, sinapic, cinnamic, and ellagic acids and p-hydroxybenzaldehyde, vanillin, syringaldehyde, 2-furfural, 5-methylfurfural, and 5-methoxyfurfural. The compounds from untreated wine samples were pre-concentrated and cleaned using solid-phase extraction on RP-105 polymeric sorbent. The cartridge was conditioned with methanol and water. Co-extracted ballast substances were rinsed from the sorbent with 0.1 mol L–1 hydrochloric acid–methanol, 1:4 (v/v). Retained phenolic compounds were selectively eluted with diethyl ether. A linear mobile phase gradient containing 0.3% acetic acid and methanol was used for final baseline chromatographic separation on a Hypersil BDS C18 column. Limits of detection (LOD=3sbl) in the range 5.2 to 181.2 g L–1, resolution (R) better than 1.7, and repeatability of 2.7–5.1% (RSD for real samples) were achieved. The method was applied for quantification of individual phenolic compounds in barrique wines. 相似文献
12.
A. M. Nazarov S. L. Khursan G. A. Yamilova V. D. Komissarov 《Russian Chemical Bulletin》1999,48(6):1079-1085
The reactivity of 14 aldehydes with diphenylcarbonyl oxide Ph2COO was characterized by thek
33/k
31 ratio. The values ofk
33/k
31 vary from 1.3·10−2 (C6F5CHO) to 1.0 (p-Me2N-PhCHO), 70 °C, acetonitrile as the solvent. A charge transfer complex (CTC) was suggested to be primarily formed during
the reaction. The electronic effects of substituents in the reaction were analyzed using the published data. Carbonyl oxide
reacts with aldehydes as a nucleophile (at the carbon atom of the −CHO fragment to form 1,2,4-trioxolane) and also as an electrophile
(at the aromatic ring with the intermediate formation of CTC). The latter is transformed into either 1,2,4-trioxolane or the
products of oxidation of the phenyl ring.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1090–1096, June, 1999. 相似文献
13.
Małgorzata Kozyra Anna Biernasiuk Anna Malm Marcin Chowaniec 《Natural product research》2015,29(21):2059-2063
The aim of this study was to investigate phenolic acids and flavonoids in methanolic, dichloromethane, acetone and ethyl acetate extracts and fractions from inflorescences of Cirsium canum (L.). RP-HPLC analysis enabled identification of the following: chlorogenic acid, caffeic acid, p-coumaric acid, protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, syringic acid, trans-cinnamic acid, luteolin-7-glucoside, apigenin-7-glucoside, kaempferol-3-glucoside, linarin, apigenin, rutoside, luteolin and kaempferol. The antimicrobial activity of tested extracts was determined in vitro against reference microorganisms, including bacteria or fungi, belonging to yeasts. Our data showed that the tested extracts had no influence on the growth of the reference strains of Gram-negative bacteria and yeasts belonging to Candida spp. Among them, the fractions possessed the highest activity against Gram-positive bacteria, especially Streptococcus aureus and Streptococcus pneumoniae belonging to pathogens and Streptococcus epidermidis, Bacillus cereus and Bacillus subtilis belonging to opportunistic microorganisms. 相似文献
14.
4-Vinyl guaiacol (3-methoxy 4-hydroxystyrene) can be obtained by decarboxylation of ferulic acid by the strain Streptomyces setonii ATCC 39116. The formation of this metabolite was favoured by microaerobic conditions and the culture medium employed, increasing
progressively the product concentration from 543.3 up to 885.1 mg/l when aeration level was diminished, reaching a highest
volumetric productivity of 70.4 mg/l h and a product yield of 1.11 mol/mol. The identity of the metabolite was confirmed by
gas chromatography–mass spectrometry. A metabolic study of ferulic acid and the main degradation products (ferulic acid, 4-vinyl
guaiacol, protocatechuic acid, vanillyl alcohol, vanillic acid and vanillin) suggested that ferulic acid was the only substrate
capable to be transformed into 4-vinyl guaiacol by this strain of S. setonii. 相似文献
15.
Elisabeth Langer Harald Lehner Horst Neudeck Karl Schlögl 《Monatshefte für Chemie / Chemical Monthly》1978,109(4):987-999
Dipole-dipole coupling of the indane fragments in 5,5-disubstituted 2,2-spirobiindanes is predominantly responsible for the origin of optical activity in the1La-electronic transition only if both ligands exhibit strong interaction with the aromatic nuclei. This mechanism does not contribute essentially to the1Lb-Cotton effect.The band-splittings of the couplet as well as the rotational strengths of the transitions ofA andB symmetry-type in the1La-Cotton effect are in accordance with a rough calculatory estimation.The absolute configuration thus determined agrees with the chirality recently deduced by chemical methods.The rotational strengths of the1W-Cotton effect of the carbonyl derivatives4, 5, 12, 13, and15 located at appr. 320 nm are remarkably low. This can be explained on the basis of conformational considerations.
6. Mitt.:H. Neudeck undK. Schlögl, Chem. Ber.110. 2624 (1977). 相似文献
6. Mitt.:H. Neudeck undK. Schlögl, Chem. Ber.110. 2624 (1977). 相似文献
16.
为提高具抗凝血性能的阿魏酸分子在水中的溶解性进而提高其药效,利用DBI(3,4-二羟基苯甲醛)、PEG(聚乙二醇4000)和纳米Fe3O4,采用接枝的方法制备了水溶性纳米Fe3O4-DBI-PEG-阿魏酸抗凝血杂化材料,用IR、1H NMR、TG、SEM、TEM、VSM和粒度测试方法表征了产物。结果表明阿魏酸(FA)接枝在了经过DBI-PEG活化后的纳米Fe3O4氧化物表面。杂化材料具有良好的水溶性(溶解度大于10 mg·mL-1)和顺磁性。抗凝血试验表明相同条件下杂化材料的抗凝血时间和复钙时间比阿魏酸要长,杂化材料的活化部分凝血活酶时间(APTT)和凝血酶原时间(PT)比空白组要长,杂化材料的抗凝血时间随浓度的增大而延长。 相似文献
17.
Jürgen Krauß Christoph Müller Monika Klimt Leandro Jorquera Valero Jos Francisco Martínez Martin Müller Karin Bartel Ulrike Binder Franz Bracher 《Molecules (Basel, Switzerland)》2021,26(23)
The aliphatic heterocycles piperidine and morpholine are core structures of well-known antifungals such as fenpropidin and fenpropimorph, commonly used as agrofungicides, and the related morpholine amorolfine is approved for the treatment of dermal mycoses in humans. Inspired by these lead structures, we describe here the synthesis and biological evaluation of 4-aminopiperidines as a novel chemotype of antifungals with remarkable antifungal activity. A library of more than 30 4-aminopiperidines was synthesized, starting from N-substituted 4-piperidone derivatives by reductive amination with appropriate amines using sodium triacetoxyborohydride. Antifungal activity was determined on the model strain Yarrowia lipolytica, and some compounds showed interesting growth-inhibiting activity. These compounds were tested on 20 clinically relevant fungal isolates (Aspergillus spp., Candida spp., Mucormycetes) by standardized microbroth dilution assays. Two of the six compounds, 1-benzyl-N-dodecylpiperidin-4-amine and N-dodecyl-1-phenethylpiperidin-4-amine, were identified as promising candidates for further development based on their in vitro antifungal activity against Candida spp. and Aspergillus spp. Antifungal activity was determined for 18 Aspergillus spp. and 19 Candida spp., and their impact on ergosterol and cholesterol biosynthesis was determined. Toxicity was determined on HL-60, HUVEC, and MCF10A cells, and in the alternative in vivo model Galleria mellonella. Analysis of sterol patterns after incubation gave valuable insights into the putative molecular mechanism of action, indicating inhibition of the enzymes sterol C14-reductase and sterol C8-isomerase in fungal ergosterol biosynthesis. 相似文献
18.
为提高具抗凝血性能的阿魏酸分子在水中的溶解性进而提高其药效,利用DBI(3,4-二羟基苯甲醛)、PEG(聚乙二醇4000)和纳米Fe3O4,采用接枝的方法制备了水溶性纳米Fe3O4-DBI-PEG-阿魏酸抗凝血杂化材料,用IR、1H NMR、TG、SEM、TEM、VSM和粒度测试方法表征了产物。结果表明阿魏酸(FA)接枝在了经过DBI-PEG活化后的纳米Fe3O4氧化物表面。杂化材料具有良好的水溶性(溶解度大于10 mg·mL-1)和顺磁性。抗凝血试验表明相同条件下杂化材料的抗凝血时间和复钙时间比阿魏酸要长,杂化材料的活化部分凝血活酶时间(APTT)和凝血酶原时间(PT)比空白组要长,杂化材料的抗凝血时间随浓度的增大而延长。 相似文献
19.
Dr. Elmer C. Rivera Joseph W. Taylor Dr. Rodney L. Summerscales Dr. Hyun J. Kwon 《ChemistryOpen》2021,10(8):842-847
Phenolic compounds such as vanillic and p-coumaric acids are pollutants of major concern in the agro-industrial processing, thereby their effective detection in the industrial environment is essential to reduce exposure. Herein, we present the quenching effect of these compounds on the electrochemiluminescence (ECL) of the Ru(bpy)32+/TPrA (TPrA=tri-n-propylamine) system at a disposable screen-printed carbon electrode. Transient ECL profiles are obtained from multiple video frames following 1.2 V application by a smartphone-based ECL sensor. A wide range of detection was achieved using the sensor with limit of detection of 0.26 μM and 0.68 μM for vanillic and p-coumaric acids, respectively. The estimated quenching constants determined that the quenching efficiency of vanillic acid is at least two-fold that of p-coumaric acid under the current detection conditions. The present ECL quenching approach provided an effective method to detect phenolic compounds using a low-cost, portable smartphone-based ECL sensor. 相似文献
20.
Partially bio‐based poly(amide imide)s by polycondensation of aromatic diacylhydrazides based on lignin‐derived phenolic acids and aromatic dianhydrides: Synthesis,characterization, and computational studies
下载免费PDF全文
![点击此处可从《Journal of polymer science. Part A, Polymer chemistry》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Sachin S. Kuhire Pragati Sharma Suman Chakrabarty Prakash P. Wadgaonkar 《Journal of polymer science. Part A, Polymer chemistry》2017,55(21):3636-3645
Two new bio‐based diacylhydrazide monomers, namely, 4,4′‐(propane‐1,3‐diylbis(oxy))bis(3‐methoxybenzohydrazide) and 4,4′‐(propane‐1,3‐diylbis(oxy))bis(3,5‐dimethoxybenzohydrazide) were synthesized starting from lignin‐derived phenolic acids, namely, vanillic acid and syringic acid. A series of poly(amide imide)s was synthesized by polycondensation of these diacylhydrazide monomers with commercially available aromatic dianhydrides. Poly(amide imide)s showed inherent viscosity in the range 0.44–0.56 dL g?1 and exhibited good solubility in organic solvents. Poly(amide imide)s could be cast into transparent, flexible, and tough films from their N ,N‐dimethylacetamide solutions. Poly(amide imide)s showed 10% weight loss in the temperature range 340–364 °C indicating their good thermal stability. Glass transition temperature (T g) of poly(amide imides)s were measured by DSC and DMA which were in the range 201–223 °C and 214–248 °C, respectively. The T g values of poly(amide imide)s were dependent on the number methoxy substituents on aromatic rings of diacylhydrazide monomers. Molecular dynamics simulation studies revealed that chain rigidity is the dominant factor for observed trends in T g. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 3636–3645 相似文献