Band 68, Heft 9-10

Chromatographic investigation of the methylene chloride/methanol extract of the aerial parts of Artemisia herba-alba afforded a new monoterpene dimer, in addition to a known monoterpene and three known sesquiterpene lactones. The structures of the compounds were determined by comprehensive NMR analyses, including DEPT, COSY, HMQC, HMBC, and HRMS

The protective effect of black tea extract (BTE) against HgCl 2 -induced oxidative damage in Wistar rats was investigated. Rats were injected with HgCl 2 (5 mg/kg body weight in 0.9% NaCl) to induce oxidative stress. The aqueous BTE (2.5%) was prepared from CTC (curl, tear, crush) grade tea. BTE was fed to control and HgCl2-treated rats by gavage at a dose of 1 ml/(100 g body weight d). Biomarkers of oxidative stress, such as the erythrocyte plasma membrane redox system (PMRS) activity, lipid peroxidation, and advanced oxidation protein products (AOPP), increased by 166, 31, and 373%, respectively, in response to HgCl 2 treatment, while intracellular glutathione and plasma antioxidant potential, i.e. ferric reducing ability (FRAP) decreased by 75 and 22%, respectively. BTE protected the rats against HgCl 2 -induced oxidative damage and raised the antioxidant potential in control rats. Due to its strong antioxidant effect in vivo, black tea intake may provide a significant healthpromoting effect to humans

Hepatitis C virus (HCV) NS3-NS4A protease is an attractive target for anti-HCV agents because of its important role in replication. In this work, we demonstrated that the ethyl acetate extract of the endophytic fungus Penicillium chrysogenum exhibited a potent activity against HCV NS3-NS4A protease with an IC 50 value of 20 μg/ml. The fungus was isolated from the red alga Liagora viscida and identifi ed by its morphology and 18S rDNA. Largescale fermentation of the fungus in Czapek's peptone liquid medium followed by chromatographic purifi cation of the active extract from the liquid medium allowed the isolation of twelve known metabolites. The biological properties of the isolated compounds were explored for anti-HCV protease as well as antimicrobial and anticancer activities. A computational docking study of the active isolated compounds against HCV protease was used to formulate a hypothetical mechanism for the inhibitory activity of the active compounds on the tested enzymes

Lythrum salicaria L. (Lythraceae), a herbaceous plant growing widely in Iran, has been well known for many centuries for its astringent and styptic properties. A phytochemical investigation of this plant, based on spectroscopic analysis, identifi ed fourteen compounds: 5-hydroxypyrrolidin-2-one (1), umbelliferone-6-carboxylic acid (2), 3,3',4'-tri-O-methylellagic acid-4-O-β-D-(2"-acetyl)-glucopyranoside (3), 3,3',4'-tri-O-methylellagic acid-4-O-β- D-glucopyranoside (4), daucosterol (5), phytol (6), dodecanoic acid (7), oleanolic acid (8), 3,3',4'-tri-O-methylellagic acid (9), corosolic acid (10), β-sitosterol (11), peucedanin (12), buntansin (13), and erythrodiol (14). All compounds, except for 8 and 11, have been isolated from L. salicaria for the fi rst time. Cytotoxic activities of the compounds were examined against three cancerous cell lines, colon carcinoma (HT-29), leukemia (K-562), and breast ductal carcinoma (T47D), and Swiss mouse embryo fi broblast (NIH-3T3) cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and methotrexate as positive control. Compounds 5, 10, 11, and 14 were the most active against the HT-29 cell line with IC 50 values of 192.7, 36.8, 38.2, and 12.8 μg/mL, respectively. Compounds 14, 11, 5, and 10 were 6.4, 2.8, 2.6, and 1.4 times, respectively, more selective than methotrexate. Compound 5 was the most active against the K-562 cell line (IC 50 = 50.2 μg/mL), with a selectivity exceeding that of methotrexate 13.3 times. The results of the cytotoxic assay confi rmed that growth and proliferation of the cancer cell lines are predominantly infl uenced by triterpene derivatives and sterols of this plant

Bio-guided fractionation of the ethanolic extract of the leaves of Alstonia scholaris (Apocynaceae) growing in Egypt was carried out to evaluate its antihyperglycemic acti vity in alloxan-induced diabetic rats and its hepatoprotective activity against CCl 4 -induced hepatotoxicity in rats. The ethyl acetate fraction of the ethanolic extract showed the highest antihyperglycemic [(133.6 ± 4.2) mg/mL, relative to metformin with (92.3 ± 2.7) mg/mL] and hepatoprotective [(37.9 ± 1.4) U/L, relative to silymarin with (29.7 ± 0.8) U/L] activities. Four compounds were isolated from this fraction, and identifi ed by spectroscopic techniques and by comparison with reported data: caffeic acid and isoquercitrin for the fi rst time from this plant, in addition to quercetin 3-O-β-D-xylopyranosyl (1''' →2")-β-D-galactopyranoside (major compound) and chlorogenic acid. A validated reversed phase-high-performance liquid chromatography (RP-HPLC) method was developed for the standardization of the bio active ethyl acetate fraction. The calibration curve showed good linearity (r 2 > 0.999) within tested ranges. The relative standard deviation of the method was less than 3% for intra- (0.4 - 2.0%) and inter-day (1.9 - 2.8%) assays. Mean recovery of the method was within the range of 98.5 - 102.5%. The minimum detectable concentration of the analyte (LOD) was found to be 0.04 μg/mL. This developed HPLC method was shown to be simple, rapid, precise, reproducible, robust, specifi c, and accurate for quality assessment of the bioactive fraction

Taxonomic identifi cation of three newly isolated Antarctic fungal strains by their 18S rDNA sequences revealed their affi liation with Aspergillus fumigatus. Phenol (0.5 g/l) as the sole carbon source was completely degraded by all strains within less than two weeks. Intracellular activities of three key enzymes involved in the phenol catabolism were determined. Activities of phenol hydroxylase (EC 1.14.13.7), hydroquinone hydroxylase (EC 1.14.13.x), and catechol 1,2-dioxygenase (EC 1.13.11.1) varied signifi cantly between strains. The rates of phenol degradation in the three strains correlated best with the activity of catechol 1,2-dioxygenase. Six pairs of oligonucleotide primers were designed on the basis of the Aspergillus fumigatus Af293 genome sequence (NCBI Acc. No. XM_743491.1) and used to amplify phenol hydroxylase-related gene sequences. DNA sequences of about 1200 bp were amplifi ed from all three strains and found to have a high degree of sequence identity with the corresponding gene of Aspergillus fumigatus Af293

Metabolite profi les of Mitragyna speciosa were determined by means of 1H NMR-based and HPLC-based analyses. The results indicated that high contents of secologanin, caffeic acid, gallic acid, epigallocatechin, and mitragynine were accumulated in leaves. In M. speciosa, feedings of tryptamine, tryptophan, phenylalanine or tyrosine signifi cantly increased the mitragynine contents. Feedings of tryptamine and loganin also enhanced the mitragynine accumulation, but feeding of loganin only did not affect the mitragynine level. The mRNA levels of anthranilate synthase alpha subunit (ASA), tryptophan decarboxylase (TDC), and strictosidine synthase (STR) were measured by quantitative real-time polymerase chain reaction (RT-qPCR) in control plants and those exposed to methyl jasmonate (MJ; 10 μM). All genes responded to MJ after a 24-h treatment. The mitragynine contents were also enhanced and corresponded to the transcript levels. From the present results we conclude that a high content of secologanin together with a undetectable level of tryptamine in M. speciosa feature the limitation of mitragynine biosynthesis. Additionally, expression of all the genes limits production of an essential precursor for mitragynine production

The natural product pateamine A (pateamine) from the sponge Mycale hentscheli is active against a wide range of dividing cells and has been shown to inhibit the functions of the eukaryotic initiation factor 4A (eIF4A). We have identifi ed that pateamine is additionally able to modulate the formation of actin fi laments and microtubules in vitro but at higher concentrations than required for inhibition of eIF4A. Cell cycle analysis confi rmed that actin and tubulin are not major mediators of the cellular activity of pateamine. The range of targets identifi ed demonstrates the value of multiple approaches to determining the mode of action of biologically active compounds

The legume pod borer, Maruca vitrata (Lepidoptera: Crambidae; syn. M. testulalis), is a serious pantropical insect pest of grain legumes. Comparative studies of M. vitrata female sex pheromone components in two different geographic populations in China, Wuhan and Huazhou, confi rmed that (E,E)-10,12-hexadecadienal (E10,E12 - 16:Ald) and (E)-10-hexadecenal (E10 - 16:Ald) were present in variable ratios in all pheromone gland extracts of both populations. (E,E)-10,12-hexadecadienol (E10,E12 - 16:OH) was always detected in minor amounts using polar DB-WAX columns, but was never detected using medium-polar DB-17 columns for the two populations. E10 - 16:OH was not found in any of the M. vitrata sex pheromone gland extracts. The average ratios of E10 - 16:Ald, E10,E12 - 16:Ald, and E10,E12 - 16:OH in the pheromone gland extracts of populations from Wuhan and Huazhou were 79.5:100:12.1 and 10.3:100:0.7, respectively. Electrophysiological testing suggested that E10,E12 - 16:Ald elicited the highest male electroantennography (EAG) response, followed by E10,E12 - 16:OH and E10 - 16:Ald. Field-trapping tests with single synthetic sex pheromone lures showed that E10,E12 - 16:OH alone could not attract males, whereas E10,E12 - 16:Ald or E10 - 16:Ald alone attracted few males. Wuhan and Huazhou males were most attracted by lures containing E10 - 16:Ald + E10,E12 - 16:Ald + E10,E12 - 16:OH in doses of (80 + 100 + 10) μg and (10 + 100 + 10) μg, respectively, per vial. Males could discriminate between the blends that were most attractive to their own geographic population and those that were most attractive to the reference population. Our fi ndings suggest that geographic variation exists in the sex pheromone system of M. vitrata in China. The results are discussed with regard to the mechanisms underlying the sex pheromone variation