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1.
One new benzopyran derivative (2R*,4R*)-3,4-dihydro-5-methoxy-2-methyl-2H-1-benzopyran-4-ol (1), together with five known compounds (2?6), were obtained from the EtOAc extract of the endophytic fungus Penicillium citrinum HL-5126 isolated from the mangrove Brguiera sexangula var. rhynchopetala collected in the South China Sea. Their structures were elucidated by the detailed analysis of comprehensive spectroscopic data. All compounds were evaluated for their antibacterial activities. Compound 6 exhibited potent inhibitory activity against Bacillus subtilis, Bacillus cereus and Micrococcus tetragenus with the same MIC values of 6.94 μM.  相似文献   

2.
The application of multicriteria decision‐making methods to the results of in vitro antifungal properties of organotin compounds of the type PhxSnXz (x = 2 or 3; X = O2CC6H4OH, O2CC6H4OCOCH3, Cl or O2CCH3; z = 1 or 2) and of free 2‐hydroxybenzoic and 2‐acetoxybenzoic acids against Aspergillus niger, Aspergillus flavus, Candida albicans, Penicillium citrinum, Trichophyton rubrum and Trichophyton violaceum have been described. Ranking information necessary to select one toxicant in preference to others and to assess the properties influencing the preference has been obtained. Patterns in the multivariate analyses suggest that cationic and anionic moieties of the toxicant play some roles in their fungicidal activities. The triphenyltin compounds were generally more active than their diphenyltin analogues, but the acetoxybenzoates were more active than the corresponding hydroxybenzoates, acetates or chlorides. Thus, triphenyltin acetoxybenzoate is up to 7.5 times as active as the corresponding acetate, which is commercially marketed as a fungicide. The results of the analyses have been discussed in the light of the mechanism of antifungal activity of organotin compounds and the potential of multivariate data analysis techniques to facilitate the screening and ranking of antifungal agents. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

3.
Two new citrinin dimers named dicitrinones E and F (1 and 2), together with one biogenetically related known citrinin monomer (3), were isolated from the marine derived fungus Penicillium citrinum HDN-152-088. All structures including the absolute configurations were elucidated on the basis of comprehensive spectroscopic data, and assisted by ECD calculations. Among them, compounds 1 and 2 belong to the class of citrinin dimers with a rare carbon-bridged C-7/C-7′ linkage. Compound 1 displayed antioxidant activity with IC50 value of 23.73 μM.  相似文献   

4.
A fungal isolate, identified as Penicillium citrinum S2, produced ≈1 U/mL of PHB depolymerase by 72 h when grown in BHM containing 0.2%, w/v PHB, pH 6.0 at 30 °C. Partial purification of an extracellular poly(-β-)hydroxybutyrate (PHB) depolymerase PhaZ Pen from P. citrinum S2 by two steps using ammonium sulphate (80% saturation) and affinity chromatography using concanavalin A yielded 16.18-fold purity and 21.53% recovery of protein. The enzyme was composed of three polypeptide chains of 66, 43 and 20 kDa, respectively, as determined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. All the three bands stained positive for glycoprotein by PAS staining. Optimum enzyme activity was detected at pH 6.0 and 50 °C. The enzyme was stable between pH 4.0 and 7.0 at 50 °C, 2 h. β-hydroxybutyrate monomer was detected as the major end product of PHB hydrolysis. The enzyme also showed distinct behaviour towards different inhibitors tested, which suggests the role of serine, serine residue, carboxyl group, tyrosine and sulfhydryl groups in its active site.  相似文献   

5.
Two new compounds penibenzophenones A-B (1–2), and the synthetic α,β-unsaturated amide alkaloid (E)-tert-butyl(3-cinnamamidopropyl)carbamate (4), newly identified as a natural product, alone with three known ones (3, 5–6) were isolated from the EtOAc extract of the endophytic fungus Penicillium citrinum HL-5126 isolated from the mangrove Bruguiera sexangula var. rhynchopetala collected in the South China Sea. Compound 1 was a chlorinated benzophenone. The structures of 1–6 were elucidated by extensive NMR spectral interpretation, MS data and X-ray analysis. The new compound 2 displayed cytotoxic activity against human A549 cell lines with an IC50 value of 15.7 μg/mL, and 1 showed antibacterial activity against Staphylococcus aureus with a MIC value of 20 μg/mL.  相似文献   

6.
A series of 5-((1H-1, 2, 4-triazol-1-yl)methyl)-4H-1,2,4-triazole derivatives were prepared and evaluated for their antifungal activities. Quantitative structure–activity relationship studies were performed on these compounds using physicochemical parameters as independent parameters and antifungal activity as a dependent parameter, where antifungal activity correlated best (correlation coefficient r > 0.8) with physicochemical parameters (Hammett’s constants σ p , F) and van der Waals volume V 1. Results are interpreted on the basis of multiple regression and cross-validation methodology. Furthermore, the domain of applicability which indicates the area of reliable predictions is defined. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Chemical structures of A1–26 and A39; synthetic procedures; synthesis schemes; mps, yields, 1H NMR; elemental analyses of compounds and single crystal X-ray diffraction of compounds.  相似文献   

7.
This work is a study of lipase production by a Brazilian strain ofPenicillium citrinum using an inexpensive and simple medium without organic nitrogen sources and of some important industrial properties, including thermostability in relation to ionic strength. The maximal lipase activity (1585 U/L) was obtained whenPenicillium citrinum was cultured on 0.75% ammonium sulfate complemented with minerals salts instead of yeast extract. Although this activity was about 55% lower than that produced in medium with yeast extract (2850 U/L), the specific activity (7.8 U/mg proteins) was higher than that obtained with the yeast extract (4.9 U/mg proteins). The morphology of fungus changed totally, with yeast extract there are smooth, solid, and spherical pellets whereas on ammonium sulfate there are small “hairy” pellets uniformly suspended in the medium. The effect of ferrous (Fe++) ions was carried out using medium MA with and without Fe++ ions. Lipase production byPenicillium citrinum in medium MA requires Fe++ ions, the absence of which caused a decreased of about 50% in the specific activity (3.5 U/mg proteins). The utilization of commercial, locally available oils as carbon sources, such as soybean oil (236 U/L) and corn oil (74 U/L) resulted in lower activity compared to olive oil, showing that lipase production byPenicillium citrinum is specifically induced by olive oil. Potassium concentration in the medium can effects the production of lipase (1 mM (1585 U/L), 10 mM (1290 U/L), and 30 mM (1238 U/L), 50 mM (195 U/L), and 100 mM (2 U/L). The crude culture filtered was susceptable to thermal deactivation. It was stable at pH 6.0, but was not stable at the optimum pH (8.0-8.5) at 50 mM. At the low ionic concentration (1-25 mM) this lipase was stable at low pH (3.5-4.0). The activation energy was 22.4 ±2.2 Kcal. mol 1.  相似文献   

8.
The purpose of this work was to purify a protease from Penicillium waksmanii and to determine its biochemical characteristics and specificity. The extracellular protease isolated that was produced by P. waksmanii is a serine protease that is essential for the reproduction and growth of the fungus. The protease isolated showed 32 kDa, and has optimal activity at pH 8.0 and 35 °C towards the substrate Abz-KLRSSKQ-EDDnp. The protease is active in the presence of CaCl2, KCl, and BaCl, and partially inhibited by CuCl2, CoCl2 and totally inhibited by AlCl3 and LiCl. In the presence of 1 M urea, the protease remains 50 % active. The activity of the protease increases 60 % when it is exposed to 0.4 % nonionic surfactant-Triton X-100 and loses 10 % activity in the presence of 0.4 % Tween-80. Using fluorescence resonance energy transfer analysis, the protease showed the most specificity for the peptide Abz-KIRSSKQ-EDDnp with k cat/K m of 10,666 mM?1?s?1, followed by the peptide Abz-GLRSSKQ-EDDnp with a k cat/K m of 7,500 mM?1?s?1. Basic and acidic side chain-containing amino acids performed best at subsite S1. Subsites S2, S3, S 2, and S 1, S 3 showed a preference for binding for amino acids with hydrophobic and basic amino acid side chain, respectively. High values of k cat/K m were observed for the subsites S2, S3, and S 2. The sequence of the N-terminus (ANVVQSNVPSWGLARLSSKKTGTTDYTYD) showed high similarity to the fungi Penicillium citrinum and Penicillium chrysogenum, with 89 % of identity at the amino acid level.  相似文献   

9.
A lipases (glycerol ester hydrolases E. C. 3.1.1.3) from a brazilian strain ofPenicillium citrinum has been investigated. When the microorganism was cultured in the simple medium (1.0% olive oil and 0.5% yeast extract), using olive oil in as carbon source in the inocula, the enzyme extracted showed maximum activity (409 IU/mL). In addition, decrease of yeast extract concentration also reduces the lipase activity. Nevertheless, when yeast extract was replaced by ammonium sulfate, no activity was detected. Purification by precipitation with ammonium sulfate showed best activity in the 40–60% fraction. The optimum temperature for enzyme activity was found in the range of 34–37°C. However, after 30 min at 60°C, the enzyme was completely inactivated. The enzyme showed optimum at pH 8.0. The dried concentrated fraction (after dialysis and lyophilization) maintained its lipase activity at room temperature (28°C) for 8 mo. This result in lipase stability suggests an application of lipases fromP. citrinum in detergents and other products that require a high stability at room temperature.  相似文献   

10.
A new carboxylic acid, 2‐{[5‐(2‐nitrophenyl)furan‐2‐yl]methyleneamino}benzoic acid (HOBZ), has been produced by reacting 5‐(2‐nitrophenyl)furfural with 2‐aminobenzoic acid. Reactions of NaOBZ with organotin chlorides led to formation of [Me3Sn(OBZ)] ( 1 ), [Bu3Sn(OBZ)] ( 2 ), [Me2Sn(OBZ)2] ( 3 ) and [Bu2Sn(OBZ)2] ( 4 ). Complexes 1 , 2 , 3 , 4 have been characterized using elemental analyses and infrared, 1H NMR, 13C NMR, 119Sn NMR and 119Sn Mössbauer spectroscopies. In the solid state, the OBZ ligands might coordinate to tin in an anisobidentate fashion via the carboxylate group. The in vitro antimicrobial activity of all compounds has been screened against the following fungi: Aspergillus niger, A. flavus, A. parasiticus, Penicillium citrinum, Candida dubliniensis, C. lusitaniae, C. albicans, C. tropicalis, C. parapsilosis and C. glabrata; and against the following bacteria: Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Streptococcus sanguinis, Escherichia coli, Citrobacter frendii, Salmonella typhimurium and Pseudomonas aeruginosa. Complexes 2 and 4 exhibited higher biocide activity in comparison to 1 and 3 and to the control drugs nystatin and miconazole nitrate for the yeasts, and chloramphenicol and ampicillin for the bacteria. The biological activity of 2 was superior to that of 4 . In addition, the toxicity of HOBZ, NaOBz and 1 , 2 , 3 , 4 were determined using Chlorella vulgaris, revealing low toxicity of the complexes at MIC50 concentrations. We also performed cell viability studies, using XTT assay, displaying no change in the mitochondrial function after 2–4 h of exposure of the microorganism to the complexes at MIC50 concentrations. The butyl‐containing complexes 2 and 4 display greater lipophilicities than do the methyl analogues 1 and 3 , thereby endowing 2 and 4 with superior abilities to cross the microbe cell membrane, the possible mechanism of action. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

11.
Structures and state in solutions of natural polyphenol gossypol and four its imino derivatives, three of which were synthesized for the first time, were studied by IR and NMR spectroscopy, and by quantum chemistry. The reaction of these compounds with 2,2-diphenyl-1-picrylhydrazyl (DPPH) in ethanol was examined. The antioxidant activity of the studied compounds in the reaction with DPPH was evaluated using the values of the stoichiometric coefficients of reaction, EC50, T 12/DPPH and AE parameters. Gossypol hydrazones were shown to be 5–10 times more efficient, while Schiff base to be less efficient as antioxidants in comparison with gossypol itself. The influence of metal cations on the antioxidant activity of gossypol derivatives was studied.  相似文献   

12.
Three new metabolites, norcyclocitrinol A ( 1 ), erythro‐11α‐hydroxyneocyclocitrinol ( 2 ), and pesudocyclocitrinol A ( 3 ), along with six known analogs, i.e., neocyclocitrinols A–D ( 4 – 7 , resp.), cyclocitrinol ( 8 ), and 24‐epicyclocitrinol ( 9 ), were isolated and identified from the culture broth of Penicillium chrysogenum P1X, a fungal endophyte of Huperzia serrata. Compounds 1 – 9 were identified by spectroscopic methods to share the same C25‐steroid skeleton featuring an unusual bicyclo[4.4.1] A/B ring system. In particular, 1 represents the first example of a C25 steroid with a bisnor C‐atom side chain. All compounds were evaluated for their cytotoxic activities against HeLa and HepG2 cell lines. However, none of them exhibited a significant cytotoxicity at a concentration of 20 μM .  相似文献   

13.
Two new benzopyranones, named coniochaetones E (1) and F (2), one new xanthone, penicillone C (3), and one new benzophenone, penicillanone (4), are isolated from the soil fungus Penicillium citrinum PSU-RSPG95, together with ten known compounds. Their structures are identified on the basis of spectroscopic data. The isolated compounds are evaluated for their cytotoxic activity.  相似文献   

14.
The Pol6 mutant of Penicillium occitanis fungus is of great biotechnological interest since it possesses a high capacity of cellulases and β-glucosidase production with high cellulose degradation efficiency (Jain et al., Enzyme Microb Technol, 12:691–696, 1990; Hadj-Taieb et al., Appl Microbiol Biotechnol, 37:197–201, 1992; Ellouz Chaabouni et al., Enzyme Microb Technol, 16:538–542, 1994; Ellouz Chaabouni et al., Appl Microbiol Biotechnol, 43:267–269, 1995). In this work, two forms of β-glucosidase (β-glu 1 and β-glu 2) were purified from the culture supernatant of the Pol6 strain by gel filtration, ion exchange chromatography, and preparative anionic native electrophoresis. These enzymes were eluted as two distinct species from the diethylamino ethanol Sepharose CL6B and anionic native electrophoresis. However, both behaved identically on sodium dodecyl sulfate polyacrylamide gel electrophoresis (MW, 98 kDa), shared the same amino acid composition, carbohydrate content (8%), and kinetic properties. Moreover, they strongly cross-reacted immunologically. They were active on cellobiose and pNPG with Km values of 1.43 and 0.37 mM, respectively. β-glu 1 and β-glu 2 were competitively inhibited by 1 mM of glucose and 0.03 mM of δ-gluconolactone. They were also significantly inhibited by Hg2+ and Cu2 at 2 mM. The addition of purified enzymes to the poor β-glucosidase crude extract of Trichoderma reesei increased its hydrolytic efficiency on H3P04 swollen cellulose but had no effect with P. occitanis crude extract. Besides their hydrolytic activities, β-glu 1 and β-glu 2 were endowed with trans-glycosidase activity at high concentration of glucose.  相似文献   

15.
Two new prenylated xanthones (=9H‐xanthen‐9‐ones), garcimangosxanthones D ( 1 ) and E ( 2 ), together with the six known xanthones 3 – 8 , were isolated from the pericarp of Garcinia mangostana. Their structures were determined by analysis of their spectroscopic data. All of the isolated compounds were biologically evaluated for their in vitro cytotoxic activity against A549, Hep‐G2, and MCF‐7 human‐cancer cell lines and antioxidant activity. Compound 1 exhibited moderate cytotoxicity against Hep‐G2 (IC50=19.2 μM ) and weak cytotoxicity against MCF‐7 (IC50=62.8 μM ) cell lines, and compound 2 showed moderate cytotoxicity against A549, Hep‐G2, and MCF‐7 cell lines with IC50 values of 12.5–20.0 μM (Table 2). Both compounds 1 and 2 demonstrated a weak antioxidant activity with ferric reducing antioxidant power (FRAP) values of 41±7 and 130±4 μmol/g, respectively (Table 3).  相似文献   

16.
Abstract

A new rotenoid named 12-O-methylrotenolol along with five known rotenoid and isoflavone metabolites were isolated from the seeds of Dalbergia lanceolaria subsp. paniculata, collected from Egypt. The structures of these compounds were identified by physical and spectroscopic data measurements ([α]D, UV, 1D- and 2D-NMR and MS). The methanol extract of the seeds exhibited strong antioxidant activity with IC50 value 0.7?µg/µl against DPPH radical, in respect to quercetin as antioxidant reference (IC50 1.5?μM), while the tested compounds from this extract showed weak activities with IC50 values ranged from 19.6 to 33.0?µM.  相似文献   

17.
A novel steroidal saponin, along with 12 known steroidal compounds, was isolated from the rhizomes of Paris polyphylla var. chinensis. Spectral data, including two-dimensional NMR, showed that the structure of the novel saponin was 3β,21-dihydroxypregnane-5-en-20S-(22,16)-lactone-1-O-α-L-rhamnopyranosyl(1→2)-[β-D-xylopyranosyl(1→3)]-β-D-glucopyranoside. The isolated steroidal compounds were evaluated for their cytotoxic activity on human gastric cancer cell line HepG2, SGC7901, BxPC3. Diosgenin-3-O-α-L-rhamnopyranosyl(1→2)[α-L-rabinofuranosyl(1→4)]-β-D-glucopyranoside exhibited the most potent cytotoxic activity among the isolated steroids. Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 556–560, November–December, 2007.  相似文献   

18.
Human serum paraoxonase 1 (PON1) is known as an antioxidant and is also involved in the detoxification of many compounds. In this study, a novel purification strategy was employed to purify the PON1 by using cholesterol-conjugated magnetic nanoparticles. Magnetic nanoparticles were synthesized and conjugated with cholesterol through diazotized p-aminohippuric acid. In Fourier transform infrared spectrum of cholesterol-p-aminohippuric acid-Fe3O4 nanoparticles, the appearance of peaks at 3,358.3, 1,645 cm−1, and at 2,334.9 cm−1 confirmed the conjugation. The molecular weight of purified PON1 was nearly 45 kDa on sodium dodecyl sulfate (SDS)–polyacrylamide gel electrophoresis (PAGE), and isoelectric point was 5.3. The specific activity was 438 U mg−1 protein, and the purification fold was 515 with 73% yield. The K m values were 1.3 and 0.74 mM with paraoxon and phenyl acetate, respectively. Western blot of 2D-PAGE confirmed the homogeneity and stability of the enzyme. Mg+2, Mn+2, glycerol, (NH4)2SO4, PEG 6000, Triton X-100, and phenylmethylsulfonyl fluoride did not show any effect on activity. Pb+2, Co+2, Zn2+, ethanol, β-mercaptoethanol, and acetone reduced the activity while Ni2+, Cd2+, Cu2+, iodoacetic acid, SDS, dimethylformamide, DMSO inhibited the activity. In vitro enzyme activity was slightly reduced by acetyl salicylic and acetaminophen and reduced 50% with amino glycosides and ampicillin antibiotics at concentrations of 0.6 and 30 mg ml−1, respectively. This is the first report for the synthesis of cholesterol-conjugated magnetic nanoparticles for simple purification of PON1 enzyme.  相似文献   

19.
The present work was aimed that the two Ruthenium compounds namely, [Ru(A)2(B)]Cl2, where A = 1,10‐phenanthroline; B = 2‐NO2‐phenyl thiosemicarbazone (Compound R1)/2‐OH‐phenyl thiosemicarbazone (Compound R2) have been tested for antibacterial activity at the concentrations of 1 mg/mL against various Gram‐Positive organisms (Lactobacillus, Staphylococcus pyrogenes, Bacillus subtilis, Staphylococcus aureus & Bacillus megatarium) and Gram‐Negative organisms (Pseudomonas aeruginosa, Escherichia coli, Proteus vulgaris, Enterobacter aerogenes, Salmonella paratyphi, Klebsiella pneumonia & Proteus mirabilis). The compounds were also tested for antifungal activity against Aspergillus clavatus, Aspergillus niger, Colletotrichum & Penicillium notatum by using agar diffusion assay and antimalarial activity against Plasmodium falciparum (Strain 3D7) using MTT assay. The results concluded that the compound R1 exhibited significant antibacterial activity than R2 against Gram‐Negative bacteria with zones of inhibition ranging from 15‐20 mm. and mild antibacterial activity against Gram‐Positive bacteria in comparison to tetracycline, streptomycin and rifampicin. These complexes were found to have moderate antifungal activity with no activity was however observed against Aspergillus niger. The compound, R1 exhibited antimalarial activity at 10 μg/mL, whereas R2 did not show antimalarial activity upto 50 μg/mL. Sensitivity to the compounds was greatest in the gram‐negative bacteria, followed by the gram‐positive bacteria and fungi.  相似文献   

20.
Ten different fungal strains from the genus Aspergillus, Penicillium, and Mucor were screened for fucoidan hydrolyzing ability aiming to find microorganisms able to produce sulfated fucan-degrading enzymes. Screening was carried out by measuring the strains kinetic and morphometric behavior over plate assays using Laminaria japonica fucoidan as only carbon source, testing three nitrogen sources (urea, peptone, and sodium nitrate). The selected fungal strains were subsequently used in submerged fermentations, which were performed for (1) selection of the strains able to growth over fucoidan medium and (2) media selection, testing the synergy of fucoidan with other sugars for inducing high enzyme titles. Radial expansion and hyphae parameters were observed for Aspergillus niger PSH, Mucor sp. 3P, and Penicillium purpurogenum GH2 grown only over fucoidan-urea medium. A. niger PSH showed the maximum enzymatic activity values, which were significantly different (p < 0.05) from those achieved by the other selected fungi. Sucrose addition to fucoidan media proportioned the highest fucoidanase activity values for this fungal strain. This research allowed establishing optimal conditions for metabolites synthesis by fungal stains able to act toward fucoidan ramified matrix.  相似文献   

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