Search results for "Activity"
showing 10 items of 7178 documents
Potential allelopathic activity ofSideritis italica(Miller) Greuter et Burdet essential oil
2011
Sideritis italica (Miller) Greuter et Burdet is a widespread Mediterranean Lamiacea. Essential oils from S. italica flowerheads and leaves were extracted by hydrodistillation and then tested for their potential allelopathic activity against Raphanus sativus L. (Magnoliophyta) and the moss Tortula muralis (Hedw.) (Bryophyta), two organisms already tested for allelopathy, and against two bryophytes growing in the same environment as S. italica: the moss Bryum capillare Hedw. and the liverwort Lunularia cruciata (L.) Dum. For R. sativus, we considered seed germination and root and epicotyl growth. For the mosses, we used spore germination and protonemata development, while for the liverwort, w…
Changes of morphogenic competence in mature Pinus sylvestris L. buds in vitro.
2002
The effects of season and cold storage on morphogenic competence in mature Pinus sylvestris buds were investigated. Peroxidase and polyphenol oxidase activity were measured as markers of oxidative metabolism. No growth in vitro was observed on explants detached from the end of January until the beginning of March. Brachioblasts, each with a couple of needles, formed on 11 % of the buds without macrostrobili that were detached in early April and introduced immediately into culture. Of the explants detached in late July, 15 % formed shoots with brachioblasts and needles. The lowest activity of peroxidase and polyphenol oxidase in pine buds was observed from the end of April until the beginnin…
Antifeedant activity of neo-clerodane diterpenoids from Teucrium fruticans and derivatives of fruticolone
1999
The antifeedant activity of three neo-clerodane diterpenoids, fruticolone, isofruticolone and fruticolide from Teucrium fruticans was assessed using larvae of Spodoptera littoralis. Isofruticolone was one of the most potent of the Teucrium derived neo-clerodanes. Chemical modification of functional groups on fruticolone showed that its activity could be enhanced.
Use of molecular topology in the selection of new cytostatic drugs
2000
Abstract Connectivity indices are the topological descriptors that are able to predict different chemical and biological properties of the organic compounds. Recently, our research group has demonstrated their usefulness in selecting new cytostatic compounds, all of them showing antibacterial activity. In this paper we realize that this ability is considerably increased by using our home-made pharmacological distribution diagrams (PDDs) together with the topological charge indices, so that the efficient selection of new candidates within heterogeneous sets of compounds is possible. This is a straightforward way for the design and/or selection of new active compounds on virtually any type of…
Organometallic complexes with biological molecues, part 3.in vivo cytotoxicity of diorganotin (IV) chloro and triorganotin (IV) chloro derivatives of…
1994
In order to obtain a continuous source of mitotic metaphases, gill tissue of Aphaius fasciatus (Pisces, Cyprinodontiformes) has been successfully employed. Results gathered after exposure of fish to R2SnClpenG, R3SnClpenGNa, to the parents R2SnCl2, R3SnCl and to penGNa (penGNa = penicillinGNa; R = methyl, butyl and phenyl) suggest that both the parent organotin (IV) chloride and organotin (IV) chloropenG derivatives are toxic while penGNa exerts no significant toxic activity. Essentially, all of the chromosome abnormalities are classifiable as irregularly staining of chromosomes, breakages, side-arm bridges or pseudochiasmata.
ChemInform Abstract: Syntheses of Some Biologically Active Compounds from Stilbenes Isolated from the Bark of Picea abies.
2010
From the four stilbenes 1–4 isolated from the bark of Picea abies seven compounds 5–11 were obtained by hydrogenation or permethylation. 1H-, 13C-NMR and mass spectra were used for their characterization. The antileukemic activity of each compound was preliminary tested. Some compounds were further tested for their anti-HIV activity.
A diterpenoid with antifeedant activity from Scutellaria rubicunda
1999
Abstract Two diterpenoids have been isolated from Scutellaria rubicunda subsp. linneana : (11 S ,13 S ,15 R and S , 16 R ,19 S )-6 α -acetoxy-19-tigloyloxy-2 α ,19;4 α ,18;11,16;15,16-tetraepoxy-neo-clerodan-15-ol (scutecyprol B) and (11 S ,13 S ,15 R and S , 16 R ,19 S )-6 α -acetoxy-2 α ,19;4 α ,18;11,16;15,16-tetra-epoxy-neo-cleroda-15,19,diol (scutalbin C). Both compounds were tested for antifeedant activity against larvae of some species of Lepidoptera. Scutecyprol B shows potent activity at 100 ppm.
T cell specificity and cross reactivity towards enterobacteria,Bacteroides,Bifidobacterium, and antigens from resident intestinal flora in humans
1999
BACKGROUNDT cell responses to normal intestinal bacteria or their products may be important in the immunopathogenesis of chronic enterocolitis.AIMSTo investigate the T cell specificity and cross reactivity towards intestinal bacteria.PATIENTS/METHODST cell clones were isolated with phytohaemagglutinin from peripheral blood and biopsy specimens of inflamed and non-inflamed colon from five patients with inflammatory bowel disease (IBD) and two controls. T cell clones were restimulated with anaerobicBacteroides andBifidobacteria species, enterobacteria, and direct isolates of aerobic intestinal flora. T cell phenotype was analysed by single-cell immunocyte assay.RESULTSAnalysis of 96 T cell cl…
Grape pulp, grape pips and their mixture: Novel substrates or supports for solid state fermentation
1997
Grape marc, comprising of grape pulp and grape pips, is generated in high quantities during ethanol production, but has no significant commercial value. The components of the grape marc, individually or in combination, can serve as substrate or support in solid state fermentation. The potential benefits of sieved fractions (800-3150 µm particle size) was, therefore, evaluated using Trichoderma viride, with or whithout enrichment. Based on sorption isotherm profiles, grape pulp showed the best performance, though its ability to promote biomass formation was the lowest. The latter could be improved by enrichment with glucose. It, thus, offers potential as a reusable support. Grape pips promot…
Distributions of the growth rate of the germ tubes and germination time of Penicillium chrysogenum conidia depend on water activity
2008
The effects of water activities for sporulation (a(wsp)) and germination (a(wge)) on the distributions of the growth rate of the germ tubes (mu) and the germination time (t(G)) of Penicillium chrysogenum conidia were determined by monitoring the length of the same germ tubes throughout the experiments automatically. No relationship between the individual t(G)'s and mu's could be established. Irrespective of the water activity for germination, mu was greater and t(G) was less for conidia produced at 0.95a(wsp) than that at 0.99a(wsp). At 0.99 a(wge) the mean and the standard deviation of t(G) were smaller than those obtained at 0.95a(wge). At 0.99a(wge), normal distributions for mu and t(G) …