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Showing papers in "Zeitschrift für Naturforschung C in 2010"


Journal ArticleDOI
TL;DR: Lichen secondary compounds have several possible biological roles, including photoprotection against intense radiation, as well as allelochemical, antiviral, antitumor, antibacterial, antiherbivore, and antioxidant action.
Abstract: Lichens are symbiotic organisms of fungi and algae or cyanobacteria. Lichen-forming fungi synthesize a great variety of secondary metabolites, many of which are unique. Developments in analytical techniques and experimental methods have resulted in the identification of about 1050 lichen substances (including those found in cultures). In addition to their role in lichen chemotaxonomy and systematics, lichen secondary compounds have several possible biological roles, including photoprotection against intense radiation, as well as allelochemical, antiviral, antitumor, antibacterial, antiherbivore, and antioxidant action. These compounds are also important factors in metal homeostasis and pollution tolerance of lichen thalli. Although our knowledge of the contribution of these extracellular products to the success of the lichen symbiosis has increased significantly in the last decades, their biotic and abiotic roles have not been entirely explored.

367 citations


Journal ArticleDOI
TL;DR: It is demonstrated that all terpenes tested had hypotensive activity in rats and that the pharmacological effect of the terpene alcohols was more effective than that of the Terpene hydrocarbons.
Abstract: The cardiovascular activity of essential oils has been reported. Some studies showed that the main chemical components of these oils contribute to their pharmacological activity. Therefore, the cardiovascular activity of four monoterpenes and one sesquiterpene was evaluated in the present work. In non-anaesthetized normotensive rats, (+)-alpha-pinene, (-)-beta-pinene, (+/-)-citronellol and (+/-)-linalool (1, 5, 10, and 20 mg/kg, i.v.) induced hypotension [maximal effect: (-35 +/- 3)%, (-46 +/- 4)%, (-48 +/- 2)% and (-40 +/- 2)%, respectively; n=6] and tachycardia [maximal effect: (13 +/- 4)%, (16 +/- 7)%, (21 +/- 1)% and (19 +/- 3)%, respectively; n=6] while (-)-a-bisabolol (1, 5, 10, and 20 mg/kg, i.v.) induced hypotension [maximal effect: (-47 +/- 8)%, n=6] and bradycardia [maximal effect: (-57 +/- 3)%]. In conclusion, these results demonstrated that all terpenes tested had hypotensive activity in rats and that the pharmacological effect of the terpene alcohols was more effective than that of the terpene hydrocarbons.

54 citations


Journal ArticleDOI
TL;DR: This is the first report on antimicrobial activity of the major components of rosemary oil against oral pathogens and the pure major compounds were more active than the essential oil.
Abstract: The essential oil of Rosmarinus officinalis L. (rosemary) was obtained by hydro-distillation and analysed by gas chromatography-mass spectrometry. Sixty-two constituents were identified, representing 98.06% of the total oil content. Oxygenated monoterpenes were the predominant components. The rosemary oil was characterized as having prominent (> 5%) contents of camphor (18.9%), verbenone (11.3%), a-pinene (9.6%), beta-myrcene (8.6%), 1,8-cineole (8.0%), and beta-caryophyllene (5.1%). The antimicrobial activity of the oil as well as of its major constituents was tested against the following microorganisms: Streptococcus mutans, Streptococcus mitis, Streptococcus sanguinis, Streptococcus salivarius, Streptococcus sobrinus, and Enterococcus faecalis, which are potentially responsible for the formation of dental caries in humans. The microdilution method was used for determination of the minimum inhibitory concentration (MIC) during evaluation of the antibacterial activity. The essential oil displayed low activity against the selected microorganisms. In the present study, the pure major compounds were more active than the essential oil. Among all the microorganisms tested, the pathogen S. mitis was the most susceptible and E. faecalis was the most resistant to the evaluated samples. This is the first report on antimicrobial activity of the major components of rosemary oil against oral pathogens.

51 citations


Journal ArticleDOI
TL;DR: The results showed that the hydrochloric acid method exhibited the highest percentage of deproteinization, but only a little higher percentage of mannan oligosaccharide loss than the other two methods.
Abstract: Extraction of mannan oligosaccharides from the yeast cell wall and methods of deproteinization were studied. We extracted crude mannan oligosaccharides by the dilute alkali-Sevage method. The percentages of deproteinization and mannan oligosaccharide loss were compared as indexes using the Sevage method, trichloroacetic acid method, and hydrochloric acid method. The results showed that the hydrochloric acid method exhibited the highest percentage of deproteinization, but only a little higher percentage of mannan oligosaccharide loss than the other two methods.

48 citations


Journal ArticleDOI
TL;DR: Investigation of the antibacterial compounds from the Antarctic lichen species Ramalina terebrata showed the strong antibacterial potential of these compounds against B. subtilis.
Abstract: The development of new antibacterial compounds is an urgent issue to meet the evolution of resistivity of pathogenic bacteria against the available drugs. The objective of this study was to investigate the antibacterial compounds from the Antarctic lichen species Ramalina terebrata. A total of five compounds, usnic acid, usimine A, usimine B, usimine C, and ramalin, were isolated by bioactivity guided-fractionation of the methanol extract of R. terebrata after several chromatographic procedures. The qualitative antibacterial activities of the crude extract and isolated compounds were determined by the disk diffusion method while the minimum inhibitory concentration (MIC) determination assay gave the quantitative strength of the test samples. All the test samples showed antibacterial activity against Bacillus subtilis. The crude extract and usnic acid showed antibacterial activity against Staphylococcus aureus. The MIC values of the isolated compounds against B. subtilis were in the range of 1 to 26 microg/mL. These observed experimental data showed the strong antibacterial potential of these compounds against B. subtilis.

44 citations


Journal ArticleDOI
TL;DR: It was demonstrated that progesterone and β-estradiol even at low concentrations increase the germination velocity and resistance to stress conditions by changing the activities of some biochemical pathways.
Abstract: Effects of progesterone and beta-estradiol on morphologic (germination velocity, root and shoot length) and biochemical (activities of alpha-amylase, superoxide dismutase, peroxidase and catalase, H2O2 content, lipid peroxidation) parameters during germination and post-germination stages of chickpea seeds were studied. The seeds germinated at various hormone concentrations (10(-4), 10(-9), 10(-9), 10(-12), 10(-15) M) were harvested at the end of the 1st, 3rd, and 5th day. With comparison to the control, these hormones caused an increment in the number of germinating seeds at the end of days 1 and 3 by accelerating the seed germination. Root and shoot lengths were augmented by both hormones at all hormone concentrations tested. The highest elongation was recorded in 10(-6) M progesterone and 10(-9)-10(-12) M beta-estradiol. Similarly, activities of a-amylase and superoxide dismutase were increased by all concentrations of both hormones, and maximum increases were obtained with 10(-6) M progesterone and 10(-1)-10(-12) M beta-estradiol. In the case of superoxide dismutase activity, not only the H2O2 content but also the peroxidase and catalase activities increased. Lipid peroxidation decreased depending on an increase in the antioxidant enzyme activities. In the present study, it was demonstrated that progesterone and beta-estradiol even at low concentrations increase the germination velocity and resistance to stress conditions by changing the activities of some biochemical pathways.

35 citations


Journal ArticleDOI
TL;DR: The results revealed that the structural modifi cation of lecanoric acid increases the cytotoxic activity of the derivatives tested, including n-propyl and n-butyl orsellinates.
Abstract: Lichen phenolic compounds exhibit antioxidant, antimicrobial, antiproliferative, and cytotoxic activities. The purpose of this study was to evaluate the anticancer activity of lecanoric acid, a secondary metabolite of the lichen Parmotrema tinctorum, and its derivatives, orsellinates, obtained by structural modification. A cytotoxicity assay was carried out in vitro with sulforhodamine B (SRB) using HEp-2 larynx carcinoma, MCF7 breast carcinoma, 786-0 kidney carcinoma, and B16-F10 murine melanoma cell lines, in addition to a normal (Vero) cell line in order to calculate the selectivity index of the compounds. n-Butyl orsellinate was the most active compound, with IC50 values (the concentration that inhibits 50% of growth) ranging from 7.2 to 14.0 microg/mL, against all the cell lines tested. The compound was more active (IC50 = 11.4 microg/mL) against B16-F10 cells than was cisplatin (12.5 microg/mL). Conversely, lecanoric acid and methyl orsellinate were less active against all cell lines, having an IC50 value higher than 50 microg/mL. Ethyl orsellinate was more active against HEp-2 than against MCF7, 786-0, or B16-F10 cells. The same pattern was observed for n-propyl and n-butyl orsellinates. n-Pentyl orsellinate was less active than n-propyl or n-butyl orsellinates against HEp-2 cells. The orsellinate activity increased with chain elongation (from methyl to n-butyl), a likely consequence of an increase in lipophilicity. The results revealed that the structural modification of lecanoric acid increases the cytotoxic activity of the derivatives tested.

34 citations


Journal ArticleDOI
TL;DR: Flow cytometric DNA ploidy analysis of pyridine thioglcyosides against the Hepg2 and U251 cell lines revealed that the postulated mechanism of action is cell cycle arrest in the S phase, which is similar to antimetabolites and cell cycle Arrest in the M phase.
Abstract: The present study was designed for highlighting and focusing on the cytotoxic activity of a new class of antimetabolites both on human cell lines, namely liver carcinoma cell line (Hepg2), lung carcinoma cell line (H460), breast carcinoma cell line (MCF7), brain carcinoma cell line (U251), and animal cell line EAC (Ehrlich ascites carcinoma cells). The results revealed that some of these modified deazapyrimidine thioglycosides have significant cytotoxic activity against EAC cells with growth inhibition percentage ranged between 80% to 90%. The possible inhibitory mechanism of the pyridine thioglycosides was explored by studying the cell cycle perturbation of thioglycosides against human cell lines (in vitro) as well as the most suitable time for maximum compound cytotoxic activity after 6, 18, and 24 h of incubation. To confirm the cytotoxic activity of these compounds, they have been tested for their apoptotic and antiproliferative activity in vivo against solid Ehrlich tumours using five groups of Swiss albino mice for 37 days from inoculation and three treatments, 250, 500 and 1000 microg/kg body weight. There was significant reduction in Ehrlich tumour size in case of the 500 and 1000 microg/kg body weight group but mild significant tumour reduction in the 250 microg/kg body weight group. Histograms of DNA per cell for each treatment group indicated that there was a dose-dependent increase in the preG1 phase with a corresponding complete arrest of cells from entering the G2/M phase compared to the untreated EAC group. In conclusion, pyridine thioglycosides have proven good cytotoxic effects against EAC cells and also significant cytotoxic activity against the four tested human cell lines. Flow cytometric DNA ploidy analysis of pyridine thioglcyosides against the Hepg2 and U251 cell lines revealed that the postulated mechanism of action of pyridine thioglcyosides is cell cycle arrest in the S phase. This is similar to antimetabolites and cell cycle arrest in the G2/M phase (M phase) in the same way as microtubule inhibitors like pyridine thioglycosides are cell-cycle-specific in the S phase and the M phase (in case of human cell lines) and have apoptotic effects (in case of animal cell line).

32 citations


Journal ArticleDOI
TL;DR: The aim of this work was to evaluate Himatanthus lancifolius (Muell. Arg.) Woodson, a Brazilian species of Apocynaceae, and its main indole alkaloid uleine, in order to identify new AChE inhibitors.
Abstract: Application of acetylcholinesterase (AChE) inhibitors is the primary treatment for Alzheimer's disease. Alkaloids, such as physostigmine, galanthamine, and huperzine A, play an important role as AChE inhibitors. The aim of this work was to evaluate Himatanthus lancifolius (Muell. Arg.) Woodson, a Brazilian species of Apocynaceae, and its main indole alkaloid uleine, in order to identify new AChE inhibitors. The plant fluid extract, fractions, and uleine were tested for AChE inhibitory activity using Ellman's colorimetric method for thin-layer chromatography (TLC), 96-well microplates, and also Marston's TLC colorimetric method. Both TLC assays showed similar results. At 5 mg/mL, the fluid extract inhibited the AChE enzyme by (50.71 +/- 8.2)%. The ethyl acetate fraction exhibited the highest level of AChE inhibition, followed by the dichloromethane fraction. The isolated alkaloid uleine displayed an IC50 value of 0.45 microM.

31 citations


Journal ArticleDOI
TL;DR: Neem and pyroligneous extracts had impact on hatching of S. frugiperda and D. saccharalis caterpillars.
Abstract: The control of Lepidoptera pests should be carried out before hatching of their caterpillars to avoid damage to the crops. The aim of this work was to assess the activity of neem (trade name: Natuneem, producer: Base Fertil, Chapadao do Sul, Brazil) and pyroligneous extracts (trade name: Biopirol 7M, producer: Biocarbo, Itabirito, Brazil) at 10 mL/L (1%) and 20 mL/L (2%) contents on egg masses of different ages of Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) and of Diatraea saccharalis F. (Lepidoptera: Pyralidae) at Embrapa Corn and Sorghum in Sete Lagoas, Minas Gerais State, Brazil. The tests took place in an unbiased casualized design with 12 treatments and four replications. The insecticides were diluted in water, and 0.04 mL of the solution was applied to recently laid and one- and two-day-old eggs of S. frugiperda and D. saccharalis. Caterpillars hatching from recently laid egg masses of S. frugiperda was lower with 2% pyroligneous extract [(0.02 +/- 0.00)%]. Recently laid eggs and one- or two-day-old eggs of D. saccharalis presented lower caterpillar hatching with 1% neem extract [(0.00 +/- 0.00)%, (0.00 +/- 0.00)%, and (1.00 +/- 0.01)%] and 2% neem extract [(0.00 +/- 0.00)%], compared to 1% pyroligneous extract [(27.30 +/- 3.22)%, (28.40 +/- 3.32)%, and (37.80 +/- 4.14)%] and 2% pyroligneous extract [(42.20 +/- 4.49)%, (48.70 +/- 4.97)%, and (56.60 +/- 5.52)%], respectively. Neem and pyroligneous extracts had impact on hatching of S. frugiperda and D. saccharalis caterpillars.

31 citations


Journal ArticleDOI
TL;DR: It is concluded that cell phone EMFs impair early growth of V. radiata seedlings by inducing biochemical changes.
Abstract: The indiscriminate use of wireless technologies, particularly of cell phones, has increased the health risks among living organisms including plants. We investigated the impact of cell phone electromagentic field (EMF) radiations (power density, 8.55 microW cm(-2)) on germination, early growth, proteins and carbohydrate contents, and activities of some enzymes in Vigna radiata. Cell phone EMF radiations significantly reduced the seedling length and dry weight of V radiata after exposure for 0.5, 1, 2, and 4 h. Furthermore, the contents of proteins and carbohydrates were reduced in EMF-exposed plants. However, the activities of proteases, alpha-amylases, beta-amylases, polyphenol oxidases, and peroxidases were enhanced in EMF-exposed radicles indicating their role in providing protection against EMF-induced stress. The study concludes that cell phone EMFs impair early growth of V radiata seedlings by inducing biochemical changes.

Journal ArticleDOI
TL;DR: The ALAB content of the Bulgarian cereal beverage “boza” was investigated and two strains, Bom 816 and N3, were found to possess significant amylolytic activity, both of which belong to the species Lactobacillus plantarum.
Abstract: The lactic acid fermentation is a worldwide method for cereal processing. Great diversity of fermented foods and drinks is produced with the participation of amylolytic lactic acid bacteria (ALAB). In the present study the ALAB content of the Bulgarian cereal beverage "boza" was investigated. Two strains, Bom 816 and N3, were found to possess significant amylolytic activity. The strains' identification was based on genetic criteria, namely amplified ribosomal DNA restriction analysis (ARDRA) and sequencing of the 16S rDNA. The strain Bom 816 belongs to the species Lactobacillus plantarum and N3 to Lactobacillus pentosus, being the first amylolytic representative of this species. Optimization of the media composition with starch as a sole carbon source was done. The starch hydrolysis was most efficient in medium containing 4 g/l yeast and 8 g/l meat extracts. Thus, L. plantarum Bom 816 consumed 14 g/l starch, while L. pentosus N3 consumed 17 g/l. The highest values of lactic acid reached were 9.5 g/l produced by Bom 816 and 5.5 g/l produced by N3. In the presence of yeast extract L. pentosus N3 formed 0.8-1 g/l succinic acid. Both strains produced mainly cell-bound enzymes with amylase activity, at a pH optimum of 5.5, ranging from 3-4 to 21 U/ml for L. pentosus N3 and from 0.5 to 11.5 U/ml for L. plantarum Bom 816, in dependence of the assay conditions.

Journal ArticleDOI
TL;DR: Findings suggest that atranorin might represent an important tool for the management of orofacial pain and/or inflammatory disorders.
Abstract: Physicochemical characterization and antinociceptive and anti-inflammatory activities of atranorin (AT) extracted from Cladina kalbii Ahti in formalin- and capsaicin-induced orofacial pain and anti-inflammatory tests in rodents were studied. Physicochemical characterization showed that AT has the general formula C19H18O8. Male Swiss mice were pretreated with AT (100, 200, and 400 mg/kg, i.p.), morphine (3 mg/kg, i.p.), or vehicle (0.9% saline with two drops of 0.2% Tween 80) before formalin (20 microl, 2%) or capsaicin (20 microl, 2.5 microg) were injected into the right vibrissa. Our results showed that i.p. treatment with AT displayed marked inhibitory effects in different orofacial pain tests in mice. AT (400 mg/kg, i.p.) was effective in reducing the nociceptive face-rubbing behavioural response in both phases of the formalin test, which was also naloxone-sensitive. Additionally, AT produced a significant antinociceptive effect at all doses in the capsaicin test. Such results were unlikely to be provoked by motor abnormality, since AT-treated mice exhibited no performance alteration on the rota rod apparatus. AT exhibited significant anti-inflammatory activity in the acute model of inflammation (leukocyte migration to the peritoneal cavity), carrageenan- and arachidonic acid-induced hind paw edema in rats. Additionally, AT exhibited a dose-dependent antioxidant activity in vitro, as assessed by total radical-trapping antioxidant parameter and total antioxidant reactivity assays. All these findings suggest that AT might represent an important tool for the management of orofacial pain and/or inflammatory disorders.

Journal ArticleDOI
TL;DR: The aqueous extract of Verbascum mucronatum, along with its fractions and secondary metabolites, showed DPPH scavenger effect and had the best FRAP, and one of the phenylethanoid fractions displayed the highest ferrous ion-chelating effect.
Abstract: The aqueous extract of Verbascum mucronatum Lam. along with its fractions and secondary metabolites were assessed for their antioxidant, acetylcholinesterase (AChE), and butyrylcholinesterase (BChE) inhibitory activities. The antioxidant activity was evaluated by three methods: as 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, ferrous ion-chelating effect, and ferric-reducing antioxidant power (FRAP) tests. The AChE activity was determined by the Ellman method using an ELISA microplate reader. Phytochemical investigations revealed the presence of four iridoid glucosides, ajugol (1), aucubin (2), lasianthoside I (3) and catalpol (4), two saponins, ilwensisaponin A (5) and C (6), and a phenylethanoid glycoside, verbascoside (7), in Verbascum mucronatum. Their structures were elucidated by spectral techniques. The aqueous extract and fractions including the phenylethanoid glycoside 7 showed DPPH scavenger effect and had the best FRAP. Besides these results, one of the phenylethanoid fractions displayed the highest ferrous ion-chelating effect. While only 7 was found to possess moderate AChE inhibition, the extract, fractions, and all other tested compounds did not inhibit AChE and BChE.

Journal ArticleDOI
TL;DR: The productivity of L-asparaginase was slightly enhanced when the strain was treated with cell-disrupting agents like EDTA, and the crude enzyme was purifi ed to homogeneity by ammonium sulfate precipitation, Sephadex G-100 and CM-SephadeX G-50 gel filtration.
Abstract: Cultural factors affecting the production of L-asparaginase by Streptomyces tendae isolated from laterite soil samples of Guntur region were investigated on glycerol-asparagine-salts (modified ISP-5) broth. Optimal yields of L-asparaginase were recorded in the culture medium with the initial pH 7.0 incubated at 30 degrees C for 72 h. The strain utilized sucrose (2%) and yeast (2%) extract as carbon and nitrogen sources for L-asparaginase production. The productivity of L-asparaginase was slightly enhanced when the strain was treated with cell-disrupting agents like EDTA. The crude enzyme was purified to homogeneity by ammonium sulfate precipitation, Sephadex G-100 and CM-Sephadex G-50 gel filtration. By employing sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the molecular weight of the enzyme was recorded as 97.4 kDa. This is the first report on production and purification of L-asparaginase from S. tendae.

Journal ArticleDOI
TL;DR: The data presented suggest that essential oils from E. acris and E. annuus possess antifungal activity against Candida spp.
Abstract: Antiproliferative and antifungal activities of essential oils from Erigeron acris root and herb and from Erigeron annuus herb were investigated. The cell viability assay was performed in cultured fibroblasts, cancer cell lines (MCF-7 and MDA-MBA-231), and endometrial adenocarcinoma (Ishikawa) cells as well as colon adenocarcinoma (DLD-1) cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The essential oil from E. acris root showed the highest antiproliferative activity in the MCF-7 cell line with an IC50 value of 14.5 microg/mL. No effect of the essential oil on normal cells at that concentration was found. Antifungal activity against various strains of five Candida species, i.e. C. albicans, C. glabrata, C. tropicalis, C. krusei, and C. parapsilosis, was tested by the microdilution method. It was found that all examined oils can be useful as antifungal agents against the above-mentioned species, but the essential oil of E. acris herb was the most active. Their minimum inhibitory concentrations (MIC) ranged from 30 to 0.4 microL/mL. The data presented suggest that essential oils from E. acris and E. annuus possess antifungal activity against Candida spp. and antiproliferative activity against breast cancer MCF-7 cells.

Journal ArticleDOI
TL;DR: Formation of DGIs may be a strategy of the host plants resistance to the CMV infection, and the respiration and photosynthesis capabilities in DGIs and yellow leaf tissues were measured.
Abstract: Dark green islands (DGIs) are a common symptom of plants systemically infected with the mosaic virus. DGIs are clusters of green leaf cells that are free of virus but surrounded by yellow leaf tissue that is full of virus particles. In Cucumber mosaic virus (CMV)-infected Nicotiana tabacum leaves, the respiration and photosynthesis capabilities of DGIs and yellow leaf tissues were measured. The results showed that the cyanide-resistant respiration was enhanced in yellow leaf tissue and the photosynthesis was declined, while in DGIs they were less affected. The activities of the oxygen-scavenging enzymes catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD) in infected leaves were signifi cantly higher than those in the healthy leaves, and the enzyme activities in DGIs were always lower than in the yellow leaf tissues. Reactive oxygen species (ROS) staining showed that the hydrogen peroxide content in yellow leaf tissues was apparently higher than that in DGIs, while the superoxide content was on the contrary. Formation of DGIs may be a strategy of the host plants resistance to the CMV infection.

Journal ArticleDOI
TL;DR: Gas chromatographic/mass spectrometric analysis revealed that intracellular substrate mineralization occurred through the conversion of n-alkane to the corresponding n-alksanal, and the monoterminal oxidation pathway was presumably initiated by AlkB and CYP153 terminal alkane hydroxylases.
Abstract: The newly isolated strain E1, identified as a Dietzia sp., proved to have an excellent ability to degrade n-C12 to n-C38 alkane components of crude oil. The preferred substrate was the very long-chain alkane n-eicosane at an optimal temperature of 37 degrees C and an optimal pH of 8 under aerobic conditions. The growth and substrate uptake kinetics were monitored during the n-alkane fermentation process, and Dietzia sp. E1 cells were found to possess three distinct levels of cell-surface hydrophobicity. Gas chromatographic/mass spectrometric analysis revealed that intracellular substrate mineralization occurred through the conversion of n-alkane to the corresponding n-alkanal. The monoterminal oxidation pathway was presumably initiated by AlkB and CYP153 terminal alkane hydroxylases, both of their partial coding sequences were successfully detected in the genome of strain E1, a novel member of the Dietzia genus.

Journal ArticleDOI
TL;DR: The activity-guided purification of the extract led to the isolation of malvidin-3-O-β-glucoside as an α-amylase inhibitor, which demonstrated a dose-dependent enzyme inihibitory activity.
Abstract: Vaccinium arctostaphylos is a traditional medicinal plant in Iran used for the treatment of diabetes mellitus. In our search for antidiabetic compounds from natural sources, we found that the extract obtained from V. arctostaphylos berries showed an inhibitory effect on pancreatic alpha-amylase in vitro [IC50 = 1.91 (1.89-1.94) mg/mL]. The activity-guided purification of the extract led to the isolation of malvidin-3-O-beta-glucoside as an a-amylase inhibitor. The compound demonstrated a dose-dependent enzyme inihibitory activity [IC50 = 0.329 (0.316-0.342) mM].

Journal ArticleDOI
TL;DR: The expression profile of the tea caffeine synthase (TCS) gene in developing leaves and flowers was studied by means of northern blot analysis, and compared it with those of phenylalanine ammonia lyase, which showed no effect on the expression of TCS genes.
Abstract: Caffeine (1,3,7-trimethylxanthine) is a purine alkaloid that is present in high concentrations in the tea plant Camellia sinensis. Caffeine synthase (CS, EC 2.1.1.160) catalyzes the S-adenosyl-L-methionine-dependent N-3- and N-1-methylation of the purine base to form caffeine, the last step in the purine alkaloid biosynthetic pathway. We studied the expression profile of the tea caffeine synthase (TCS) gene in developing leaves and flowers by means of northern blot analysis, and compared it with those of phenylalanine ammonia lyase (PAL, EC 4.3.1.5), chalcone synthase (CHS, EC 2.3.1.74), and S-adenosyl-L-methionine synthase (SAMS, EC 2.5.1.6). The amount of TCS transcripts was highest in young leaves and declined markedly during leaf development, whereas it remained constant throughout the development of the flower. Environmental stresses other than heavy metal stress and plant hormone treatments had no effect on the expression of TCS genes, unlike the other three genes. Drought stress suppressed TCS gene expression in leaves, and the expression pattern mirrored that of the dehydrin gene. The amounts of TCS transcripts increased slightly on supply of a nitrogen source. We discuss the regulation of TCS gene expression.

Journal ArticleDOI
TL;DR: It is shown that a rise in KNO3 concentration caused a decline in hairy roots growth, and had a remarkable effect on the alkaloid content, and increasing the nitrate concentration in the medium of hairy roots improved the hyoscyamine/scopolamine ratio, while it increased the scopolamine/hyoscyamines ratio in the studied plants.
Abstract: Plants are a potential source of a large number of valuable secondary metabolites. In vitro cultures are being considered as an alternative to agricultural processes for studying valuable secondary metabolites. In this way, nutritive factors are important parameters influencing the production of these compounds in plants. Effects of nitrate concentrations (KNO3) on the production of two tropane alkaloids, hyoscyamine and scopolamine, and the growth of aerial parts and roots of two in vitro propagated accessions of Atropa belladonna and hairy roots were investigated. As hairy roots cultures are able to keep a stable production of alkaloids over long periods of subculturing, they are considered as an interesting option for the study of alkaloid biosynthesis. A hairy roots culture of Atropa belladonna was established by transformation with Agrobacterium rhizogenes strain AR15834. The results of our study showed that a rise in KNO3 concentration caused a decline in hairy roots growth, and had a remarkable effect on the alkaloid content. The alkaloid concentrations obtained in the hairy roots were 3-20 times higher than that in the plants at 35 mM of KNO3. Increasing the nitrate concentration in the medium of hairy roots also improved the hyoscyamine/scopolamine ratio, while it increased the scopolamine/hyoscyamine ratio in the studied plants.

Journal ArticleDOI
TL;DR: A nematicide, beauvericin (1), was isolated from cultures of the fungus Fusarium bulbicola, and its structure was identified by spectroscopic analysis.
Abstract: A nematicide, beauvericin (1), was isolated from cultures of the fungus Fusarium bulbicola, and its structure was identified by spectroscopic analysis. Compound 1 showed nematicidal activities against the pine wood nematode Bursaphelenchus xylophilus and the free-living nematode Caenorhabditis elegans.

Journal ArticleDOI
TL;DR: The results showed that the compounds had cytotoxicity within the 8.2 - 32.1 μM range, while two compounds gave rise to a comparable average value in topo I interference of 42% and 40% for 10a and 5b.
Abstract: A number of studies reported Mannich bases to manifest antimicrobial, cytotoxic, anticancer, anti-inflammatory, and anticonvulsant activities. A considerable number of therapeutically important cytotoxic compounds are active on DNA topoisomerases that regulate the DNA topology. In the present study we evaluated the biological activity of mono-Mannich bases, 1-aryl-3-phenethylamino-1-propanone hydrochlorides (1a-10a), and semicyclic mono-Mannich bases, 3-aroyl-4-aryl-1-phenethyl-4-piperidinols (1b-9b), synthesized in our laboratory. We employed androgen-independent human prostate cancer cells (PC-3) to assess the cytotoxicity of the compounds and extended the biological activity evaluation to cover supercoil relaxation assays of mammalian type I topoisomerases. Our results showed that the compounds had cytotoxicity within the 8.2-32.1 microM range, while two compounds gave rise to a comparable average value in topo I interference of 42% and 40% for 10a (with a hydroxy substituent on the phenyl ring from mono-Mannich bases) and 5b (with a fluoro substituent on the phenyl ring from the semicyclic mono-Mannich base series, piperidinols), respectively.

Journal ArticleDOI
TL;DR: Differences in the expression and activity of curcin and curcin-L suggest that these two ribosome-inactivating proteins have different functions.
Abstract: To date, two types of ribosome-inactivating proteins (RIPs) have been found in Jatropha curcas. One is curcin, which has been isolated from the endosperm, and the other is curcin-L, which is expressed in leaves upon stress treatment. Phylogenetic analysis of the predicted amino acid sequences of the RIPs in plants revealed that these belong to a major subfamily and are close to trichosanthin (TCS). Studies on the mRNA and protein levels showed that both curcin and curcin-L have an organ-specific expression pattern. Curcin is only expressed and accumulated in the endosperm; its expression begins in the globular embryo period and peaks during the mature embryo period. In contrast, curcin-L is only expressed in the leaves, but its expression is induced by certain conditions such as treatment with phytohormones or polyethylene glycol, exposure to high and low temperatures, and fungal infection. Analysis of the 5' flanking regions of curcin and curcin-L revealed that the 5' flanking region of curcin-L has three major inserted fragments, which are not present in the corresponding region of curcin. Comparison of characteristic cis-elements suggests the presence of several motifs that are involved in the endosperm-specific expression in the 5' flanking region of curcin, while in curcin-L some stress- and defense-responsive motifs are found to be mainly located in the three inserted fragments. Comparison of the antifungal activity of the two RIPs showed that the one of curcin-L is higher than that of curcin. Differences in the expression and activity of curcin and curcin-L suggest that these two RIPs have different functions.

Journal ArticleDOI
TL;DR: In this paper, the authors used single stranded conformation polymorphism (SSCP) analysis for genotype identification of three breeds of chicken and evaluated the associations of these polymorphisms with the growth rate of the studied breeds.
Abstract: The insulin-like growth factor I (IGF-I) regulates growth, protein synthesis, and cell proliferation and differentiation in vertebrates. Polymorphisms of IGF-I gene transcripts of three breeds of chicken were assessed. The associations of these polymorphisms with the growth rate of the studied breeds were also evaluated. Total RNA was isolated from chicken livers, and the IGF-I gene was amplified from each breed RNA by RT-PCR using specific primers flanking a certain region of the gene. The amplified RT-PCR products were formed to identify the transcripts and to correlate them to the phenotype of growth, by performing single stranded conformation polymorphism (SSCP) analysis for genotype identification. In this report, we describe how SSCP analysis of RT-PCR products can be used to evaluate the transcript expression pattern of avian IGF-I polymorphism, and their effect on the growth traits of chickens.

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TL;DR: The compounds displayed a great scavenging activity against DPPH especially at 500 and 1000 μg ml-1, and were found to exert noteworthy reducing antioxidant power on ferric ions, while none of the compounds exhibited chelating ability against ferrous ions.
Abstract: Phytochemical investigations of Taxus baccata L. by successive chromatographic methods resulted in the isolation of the lignans lariciresinol (1), taxiresinol (2), 3'-demethylisolariciresinol-9'-hydroxyisopropylether (3), isolariciresinol (4), and 3-demethylisolariciresinol (5) as well as taxoids. Compounds 1-5 were evaluated for their acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and lipoxygenase (LOX) inhibitory activities, which play a role in the pathogenesis of Alzheimer's disease (AD), by in vitro spectrophotometric methods, while they were also screened for their antioxidant capacity in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, ferrous ion-chelating effect, and ferric-reducing antioxidant power (FRAP) at 125, 250, 500, and 1000 microg ml(-1). All compounds exhibited a moderate inhibition against both BChE and LOX, whereas they were inactive towards AChE. The compounds displayed a great scavenging activity against DPPH especially at 500 and 1000 microg ml(-1). Besides, they were found to exert noteworthy reducing antioxidant power on ferric ions. In particular, the FRAP of compounds 2 (3.552 +/- 0.02), 4 (3.021 +/- 0.71), and 5 (3.533 +/- 0.01) were as high as that of the reference chlorogenic acid (3.618 +/- 0.01) at 1000 microg ml(-1). None of the compounds exhibited chelating ability against ferrous ions.

Journal ArticleDOI
TL;DR: The NMR data showed that the isoprene units of polyisoprenoid derived from isopentenyl diphosphate, which was biosynthesized using both mevalonate and 1-deoxy-D-xylulose-5-phosphate in E. ulmoides.
Abstract: 13 C-labeled isotopomers were fed to the young seedlings, the polyisoprenoid fractions were prepared and analyzed by 13 C NMR. The NMR data showed that the isoprene units of polyisoprenoid derived from isopentenyl diphosphate, which was biosynthesized using both mevalonate and 1-deoxy-D-xylulose-5-phosphate in E. ulmoides. It is assumed that the cross-talk of isopente- nyl diphosphate, derived from both pathways, occurs during the biosynthesis of polyisopre- noid; therefore, it was observed in the formation of low-molecular weight isoprenoids.

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TL;DR: This study presents an HPLC method for simultaneous analysis of astaxanthin and its carotenoid precursors from Xanthophyllomyces dendrorhous and Peaks showed in the HPLC chromatogram are identified asCarotenoids in the monocyclic biosynthetic pathway or their derivatives.
Abstract: This study presents an HPLC method for simultaneous analysis of astaxanthin and its carotenoid precursors from Xanthophyllomyces dendrorhous. The HPLC method is accomplished by employing a C18 column and the mobile phase methanol/water/acetonitrile/ dichloromethane (70:4:13:13, v/v/v/v). Astaxanthin is quantified by detection at 480 nm. The carotenoid precursors are identified by LC-APCI-MS and UV-vis absorption spectra. Peaks showed in the HPLC chromatogram are identified as carotenoids in the monocyclic biosynthetic pathway or their derivatives. In the monocyclic carotenoid pathway, 3,3'-dihydroxy-beta,psi-carotene-4,4'-dione (DCD) is produced through gamma-carotene and torulene.

Journal ArticleDOI
Man Xiao1, Jun Ma, Hongyu Li, Han Jin, Hanqing Feng 
TL;DR: The results indicate that the H2S-induced AOX induction might play a role in inhibiting the ROS production and have an influence on cell viability.
Abstract: The toxic effects of H2S on plants are well documented. However, the molecular mechanisms reponsible for inhibition of plants by H2S are still not completely understood. We determined the effects of NaHS in the range of 0.5-10 mM on the growth of rice suspension culture cells, as well as on the expression of the alternative oxidase (AOX) gene. AOX is the terminal oxidase of the alternative pathway (AP) and exists in plant mitochondria. The results showed that H2S treatment enhanced the AP activity. During the process of H2S treatment for 4 h, the AP activity increased dramatically and achieved the peak value at a concentration of 2 mM NaHS. Then it declined at higher concentrations of NaHS (5-10 mM) and maintained a steady level. The AOX1 gene transcript level also showed a similar change as the AP activity. Interestingly, different NaHS concentrations seemed to have different effects on the expression of AOX1a, AOX1b, and AOX1c. The induction of AOX expression by low concentrations of NaHS was inferred through a reactive oxygen species (ROS)-independent pathway. At the same time, rice cells grown in culture were very sensitive to H2S, different H2S concentrations induced an increase in the cell viability. These results indicate that the H2S-induced AOX induction might play a role in inhibiting the ROS production and have an influence on cell viability.

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TL;DR: First steroid biotransformations performed by Aspergillus wentii MRC 200316 are reported and testosterone yields 6β-hydroxytestosterone and progesterone yields 11α-Hydroxyprogesterone.
Abstract: First steroid biotransformations performed by Aspergillus wentii MRC 200316 are reported. Testosterone (1) yields 6beta-hydroxytestosterone (3) and 14alpha-hydroxytestosterone (4) while progesterone (2) yields 11alpha-hydroxyprogesterone (5).