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Regulation of biosynthesis of vermiculin and vermistatin in Penicillium vermiculatum.

Biosynthesis of vermiculin (1) and vermistatin (2) in Penicillium vermiculatum can be controlled by the carbon and nitrogen sources. Glucose and sucrose affect the levels of the two metabolites; cornsteep liquor influences the quality the biosynthesis. The concentrations of Fe3+ and Cu2+ ions also affect the biosynthesis, the effect being dependent on the type of carbon source utilized. The compounds capable of electron transport generally stimulate the production of 1 and 2 but do not influence the biosynthesis qualitatively.

Antibiotics, Antineoplastic↗

New azidometalkojates and their biological activity.

Azidometalkojates of the general formula MX2 (M = Cu, Mn, Mg, Zn or Ni and X = 5-hydroxy-2-azidomethyl-4H-pyran-4-one) were prepared and tested for antibacterial, antifungal and cytotoxic effects. The mangan and zinc derivatives are not active against any the tested microorganisms. A weak antibacterial activity was found with the copper derivative. The strongest antifungal effects were shown by the nickel derivative while the highest cytotoxic effect on HeLa cells was manifested by the zinc derivative.

Anti-Bacterial Agents↗

Kojic acid production by Aspergillus flavus using gelatinized and hydrolyzed sago starch as carbon sources.

Direct conversion of gelatinized sago starch into kojic acid by Aspergillus flavus strain having amylolytic enzymes was carried out at two different scales of submerged batch fermentation in a 250-mL shake flask and in a 50-L stirred-tank fermentor. For comparison, fermentations were also carried out using glucose and glucose hydrolyzate from enzymic hydrolysis of sago starch as carbon sources. During kojic acid fermentation of starch, starch was first hydrolyzed to glucose by the action of alpha-amylase and glucoamylase during active growth phase. The glucose remaining during the production phase (non-growing phase) was then converted to kojic acid. Kojic acid production (23.5 g/L) using 100 g/L sago starch in a shake flask was comparable to fermentation of glucose (31.5 g/L) and glucose hydrolyzate (27.9 g/L) but in the 50-L fermentor was greatly reduced due to non-optimal aeration conditions. Kojic acid production using glucose was higher in the 50-L fermentor than in the shake flask.

Aspergillus flavus↗

Efficacy and tolerability of a combination of Lyprinol and high concentrations of EPA and DHA in inflammatory rheumatoid disorders.

This 12-week drug-monitoring study was conducted to evaluate the efficacy of Sanhelios Mussel Lyprinol Lipid Complex on 50 adult men and women with inflammatory rheumatoid arthritis. A total of 34 patients required drug therapy before and during the study. By the end of the study, 21 (62%) patients were able to reduce their dosage and 13 were able to terminate drug therapy. At the end of the treatment period, 38% were regarded symptom free, and the number of patients with severe pain decreased significantly from 60% at baseline to 25% at the completion of the trial. A significant effect was observed for each investigated parameter. The special combination of Lyprinol and omega-3 fatty acids was generally very well tolerated, with only one, nonserious adverse event (mild nausea) reported. This dietary supplement may therefore be considered an effective and well-tolerated component of treatment regimens for inflammatory rheumatoid arthritis.

Adult↗

The effect of Erigeron breviscapus on proliferation of pulmonary artery smooth muscle cells in hypoxic porcines.

In order to study the effect of Erigeron Breviscapus (EB) on proliferation of pulmonary artery smooth muscle cells (PASMC) in hypoxic porcines, immunohistochemical and MTT methods were employed to measure the proliferation of PASMC. It was found that the proliferation of PASMC in porcines was obvious, and the expression of proliferating cell nuclear antigen (PCNA) was significantly high within 48 h after exposure to hypoxia. The EB could inhibit the proliferation and the expression of PCNA in PASMC under hypoxia, but it had no effect on the proliferation and expression of PCNA in PASMC under normal condition. The EB could inhibit the proliferation and the expression of PCNA in PASMC induced by phorbol 12-myristate 13-acetate (PMA), an agonist of PKC in normal and hypoxic conditions. It was concluded that the hypoxia could enhance the proliferation and expression of PCNA in PASMC. The EB can inhibit the proliferation and expression of PCNA in PASMC under hypoxia through PKC-signal way. The EB may be used in treating the pulmonary hypertension by inhibiting the proliferation of PASMC and the pulmonary vascular remodeling.

Animals↗

Relationship between antifungal activity and hydrophobicity of kojic acid derivatives.

Twenty three kojic acid derivatives were tested in the agar diffusion test against twenty five dermatophytic fungi. The inhibitory effects at equal doses (10 mg/L) were correlated with the 1-octanol-water partition coefficients of the compounds. An improvement in antifungal activity can be achieved by increasing the hydrophobicity of the compounds.

Antifungal Agents↗

Naphthopyrone glucosides from the seeds of Cassia tora with inhibitory activity on advanced glycation end products (AGEs) formation.

Three naphthopyrone glucosides, cassiaside (1), rubrofusarin-6-O-beta-D-gentiobioside (2), and toralactone-9-O-beta-D-gentiobioside (3), were isolated from the BuOH-soluble extract of the seeds of Cassia tora as active constituents, using an in vitro bioassay based on the inhibition of advanced glycation end products (AGEs) to monitor chromatographic fractionation. The structures of 1-3 were determined by spectroscopic data interpretation, particularly by extensive 1D and 2D NMR studies. All the isolates (1-3) were evaluated for the inhibitory activity on AGEs formation in vitro.

Cassia↗

Kojic acid, a potential inhibitor of NF-kappaB activation in transfectant human HaCaT and SCC-13 cells.

The activation of NF-kappaB induced by kojic acid, an inhibitor of tyrosinase for biosynthesis of melanin in melanocytes, was investigated in human transfectant HaCaT and SCC-13 cells. These two keratinocyte cell lines transfected with pNF-kappaB-SEAP-NPT plasmid were used to determine the activation of NF-kappaB. Transfectant cells release the secretory alkaline phosphatase (SEAP) as a transcription reporter in response to the NF-kappaB activity and contain the neomycin phosphotransferase (NPT) gene for the dominant selective marker of geneticin resistance. NF-kappaB activation was measured in the SEAP reporter gene assay using a fluorescence detection method. Kojic acid showed the inhibition of cellular NF-kappaB activity in both human keratinocyte transfectants. It could also downregulate the ultraviolet ray (UVR)-induced activation of NF-kappaB expression in transfectant HaCaT cells. Moreover, the inhibitory activity of kojic acid in transfectant HaCaT cells was found to be more potent than known antioxidants, e.g., vitamin C and N-acetyl-L-cysteine. These results indicate that kojic acid is a potential inhibitor of NF-kappaB activation in human keratinocytes, and suggest the hypothesis that NF-kappaB activation may be involved in kojic acid induced anti-melanogenic effect.

Acetylcysteine↗

An antioxidant hispidin from the mycelial cultures of Phellinus linteus.

In the course of screening for reactive oxygen species scavengers from natural products, an antioxidant was isolated from the mycelial culture broth of Phellinus linteus and identified as hispidin. The hispidin content was reached its maximum level at 12 days after onset of inoculation. About 2.5 mg/mL of hispidin was produced by P. linteus in a yeast-malt medium (pH 5.8, 25 degrees C). Hispidin inhibited 22.6 and 56.8% of the super oxide anion radical, 79.4 and 95.3% of the hydroxyl radical, and 28.1 and 85.5% of the DPPH radical at 0.1 and 1.0 mM, respectively. The positive control alpha-tocopherol scavenged 25.6 and 60.3%, 74.6 and 96.3%, and 32.7 and 77.5% of each radical, respectively, at the same concentrations. However, hispidin showed no significant activity on the hydrogen peroxide radical.

Agaricales↗

A long-term toxicological investigation on the effect of tris(maltolate)aluminum(III) in rabbits.

The toxicity of i.v. injected hydrophilic aluminum complex tris(maltolate)aluminum(III) was studied in New Zealand white rabbits for a period of time ranging from 5 to 63 wk. Animals were injected 3-5 times a week with 1 mL of 7.5 mM Al(malt)3 and one rabbit with a dose 10 times higher after 14 wk of treatment. Autopical examination was performed on all animals. Chemoclinical analysis (glucose, urea, creatinine, cholesterol, bilirubin, alanin aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma-glutamyl-transferase, LDH, CK, total protein, triglycerides, and Ca2+) gave no variation in treated animals with respect to the control. The toxicological data show a moderate systemic general toxicity at doses far higher than those used in similar previous experiments using Al(acac)3 (acac = 2,4 pentanedionate), a hydrolytically stable and more lipophilic aluminum(III) complex (1). The diversity of behavior is discussed in terms of metal speciation as well as respect to the thermodynamic and kinetic properties of the two complexes in aqueous solution. The toxicological model presented here emphasizes that neutral, water compatible aluminum(III) complexes are to be considered as promising tools for toxicological experiments providing biological models of human pathologies.

Aluminum↗

Adverse drug reaction update.

Increasing numbers of articles on adverse drug reactions are published in a wide range of medical journals. To help keep you up-to-date with the latest advances worldwide on all aspects of adverse drug reactions, this section of the journal brings you information selected from the drug safety alerting service Reactions Weekly. The following reports are selected from the latest issues, summarizing the most important clinical studies, adverse reaction news, and expert opinion pieces published across a broad range of literature sources.

Anti-Inflammatory Agents, Non-Steroidal↗

Adverse drug reaction update.

Increasing numbers of articles on adverse drug reactions are published in a wide range of medical journals. To help keep you up-to-date with the latest advances worldwide on all aspects of adverse drug reactions, this section of the journal brings you information selected from the drug safety alerting service Reactions Weekly. The following reports are selected from the latest issues, summarizing the most important clinical studies, adverse reaction news, and expert opinion pieces published across a broad range of literature sources.

Adult↗

Inhibition of P-selectin specific cell adhesion by a low molecular weight, non-carbohydrate compound, KF38789.

OBJECTIVE AND DESIGN: P-selectin is a cell adhesion molecule of the selectin family. This study evaluated the effects of novel, low molecular weight P-selectin inhibitors in a cell adhesion assay and a murine model of peritonitis. MATERIALS: U937 or HL60 was used for cell adhesion assay. Human polymorphonuclear cells were studied for the production of superoxide. BALB/c mice were used for the in vivo study. TREATMENT: The thioglycollate (TG)-induced accumulation of leukocytes in mice was measured 6 h after the treatment. KF38789 or antibody (1 mg/kg) was injected intravenously prior to TG injection and at 3 h following initial injection. RESULTS: Low molecular weight, non-carbohydrate inhibitors against P-selectin- mediated cell adhesion were tested. One of the most potent inhibitors, KF38789, inhibited the binding of U937 cells to immobilized P-selectin immunoglobulin G chimeric protein (P-selectin-Ig) with an IC50 value of 1.97 microM. Cell adhesion to both E-selectin-Ig and L-selectin-Ig were not affected even by 100 microM of KF38789. Moreover, KF38789 inhibited P-selectin-induced superoxide production from human polymorphonuclear cells. Intravenously injected KF38789 significantly inhibited the TG-induced accumulation of leukocytes in the mouse peritoneal cavity (p<0.01). CONCLUSION: A novel low molecular weight compound, KF38789, specifically inhibited P-selectin-dependent cell adhesion and the leukocyte recruitment in mouse peritonitis.

Animals↗

Quantitative elimination of Flavokavines A and B from Kava Kava (Piper methysticum G. Forst) by isoelectric focused adsorptive bubble separation.

Adsorptive bubble separation, though still rarely used, is a suitable method for enrichment of surface-active macromolecules such as enzymes and proteins. There is a lack of investigations with small molecules, which can also be separated from complex mixtures by this method. In this work, an aqueous extract of Kava Kava ( Piper methysticum G. Forst) was used as a model system. Enrichment of undesirable Flavokavine A (7) and Flavokavine B (8) in the foam was influenced by the pH value, the amount of saponin as surface active substance, and the flow rate of the foam-forming gas. Efficiency was highest with diluted samples at pH 6.5. Under these conditions, transfer of Kavapyrone (1-6) to the foam was negligible.

Adsorption↗

Absence of liver tumor-initiating activity of kojic acid in mice.

In order to evaluate the tumor-initiating activity of kojic acid (KA) in mouse liver, an in vivo initiation assay in liver was performed using partially hepatectomized mice. Male ICR mice were fed on a basal diet (BD) containing 0 or 3% KA for 4 weeks, followed by distilled water (DW) containing 0 or 500 ppm phenobarbital (PB) for 13 weeks. Two weeks after the treatment with PB, two-thirds partial hepatectomy was preformed in all mice in order to enhance the regeneration and proliferating activities of the hepatocytes. In microscopic examinations, no proliferative lesion was observed in any of the groups. There were no differences in the number of gamma-glutamyltransferase-positive cells, an expected marker for preneoplastic hepatocytes in mice, between the KA + DW and the KA + PB groups. In the immunohistochemical analyses of the proliferating activity of hepatocytes, significant increases in the labeling index of proliferating cell nuclear antigen (PCNA) were observed in the BD + PB and KA + PB groups as compared to the BD + DW group; however, no significant difference in the positivity of PCNA was observed between the BD + PB and the KA + PB groups. These results of the present study suggest the possibility that KA has no tumor-initiating activity in the liver of mice.

Animals↗

Effect of bis(maltolato) oxovanadium on experimental vascular endothelial dysfunction.

The study has been designed to investigate the effect of bis(maltolato) oxovanadium (BMOV), a protein tyrosine phosphatase inhibitor, on hypercholesterolemia and hypertension-induced vascular endothelial dysfunction. High fat diet (8 weeks) and deoxycorticosterone acetate (DOCA; 40 mg kg(-1), s.c.) were administered to rats to produce hypercholesterolemia and hypertension (mean arterial blood pressure >120 mmHg) respectively. Vascular endothelial dysfunction was assessed using isolated aortic ring preparation, electron microscopy of thoracic aorta, and serum concentration of nitrite/nitrate. Serum thiobarbituric acid reactive substances (TBARS) were estimated to assess oxidative stress. BMOV (0.2 mg/ml in drinking water) or atorvastatin (30 mg kg(-1), p.o.) markedly improved acetylcholine-evoked endothelium-dependent relaxation, lining of vascular endothelium, serum nitrite/nitrate concentration, and serum TBARS in hypercholesterolemic and hypertensive rats. However, this ameliorative effect of BMOV has been prevented by L-NAME (25 mg kg(-1), i.p.), an inhibitor of NOS, or by glibenclamide (5 mg kg(-1), i.p.), a blocker of ATP-sensitive K(+) channels. It may be concluded that BMOV-induced inhibition of PTPase may improve vascular endothelial dysfunction.

Animals↗

Inhibition of calcium-independent phospholipase A2 activity in rat hippocampus impairs acquisition of short- and long-term memory.

RATIONALE: Phospholipase A(2) (PLA(2)) is a family of enzymes that cleave membrane phospholipids generating important lipid mediators in signal transduction. In rat hippocampal slices, both intracellular cytosolic Ca(2+)-dependent PLA(2) (cPLA(2)) and Ca(2+)-independent PLA(2) (iPLA(2)) have been implicated in mechanisms of synaptic plasticity underlying memory processes. In mice, intraperitoneal injections of a selective iPLA(2) inhibitor impaired spatial learning. Accordingly, reduced cPLA(2) and iPLA(2) activities were found in postmortem hippocampus of patients with Alzheimer's disease. OBJECTIVE: This study investigates the effects of injections of PLA(2) inhibitors directly into rat hippocampus on the acquisition of short-term (STM) and long-term memory (LTM) of a one-trial step-down inhibitory avoidance (IA) task. METHODS: Wistar rats were bilaterally implanted with cannulae in the CA1 region of the dorsal hippocampus. After surgery, the rats received bilateral injections of a vehicle, or of dual cPLA(2) and iPLA(2) inhibitors (MAFP or PACOCF(3)), or a selective iPLA(2) inhibitor (bromoenol lactone) before training in IA. The animals were tested 1.5 h (for STM) and 24 h (for LTM) after training. RESULTS: Significant inhibition of iPLA(2) activity in rat hippocampus impaired acquisition of STM and LTM. Memory impairment did not result from neuronal death after iPLA(2) inhibition. Moreover, IA training per se increased significantly hippocampal PLA(2) activity. CONCLUSION: The present results suggest a functional effect of hippocampal PLA(2) on the neurochemistry of memory acquisition and support the hypothesis that reduced PLA(2) activity may contribute to memory impairment in Alzheimer's disease.

Animals↗