bluuebunny/crossref_metadata_2025_split huggingface dataset:
Coumarin Content and Physicochemical Profile of Mikania laevigata Extracts
Authors: Biavatti Maique W. , Koerich Cesar A. , Henck Carlos H. , Zucatelli Enderson , Martineli Fernanda H. , Bresolin Tania B. , Leite Silvana N. 
Published: February 2015

The ‘guaco’ lianous herb Mikania laevigata, which is widespread in Southern Brazil, is traditionally used to treat bronchitis, asthma and cough.
This work investigates the influence of the extraction method, solvent:drug ratio, ethanol proportion, harvest season (summer or winter) and solvent heating on the physicochemical profile of the extracts (dry weight, density, pH) and the coumarin (1,2-benzopyrone) content determined by LC. Among the results obtained, it is observed that higher ethanol content increases the amount of coumarin in the extract. Leaves harvested in summer also produce an extract with a high coumarin yield. The most efficient method of extraction is percolation, independent of the solvent used.
Delayed Reproductive Death and ROS Levels in the Progeny of Irradiated Melanoma Cells
Authors: Tsoncheva Vania L. , Milchev Georgi I. 
Published: February 2015

The cell death and survival of proliferating (clonogenic) cells were investigated in two human melanoma cell lines to assess the optimal conditions for preparation of apoptotic bodies from melanoma cells. After 50 J/m2 UVB+UVC the maximal levels of apoptotic cells assayed by Trypan blue staining, nucleosomal DNA fragmentation, MTT, and TUNEL tests were observed within 2-3 d of radiation. In 100 Gy gamma-irradiated cultures these apoptosis indicators were delayed for up to 3 weeks. In addition, clonogenic cells were observed only in exponentially growing cultures irradiated with UV at high cell density but not in gamma-irradiated cultures. The response of melanoma cultures after high UV radiation doses contrasted to the response in lethally gamma-irradiated cultures. UV-irradiated melanoma cultures were recovered within two weeks. Most of the clonogenic cells in the recovered colonies contained micronuclei. ROS levels determined by DCF fluorescence and a modified MTT test were also normalized obviously due to the extensive antioxidant defense system of melanoma cells.
UV radiation of tumor cells might be the preferential method for preparation of apoptotic bodies. The presence of clonogenic cells in the suspension of apoptotic bodies from melanoma cells used for pulsing of dendritic cells with tumor antigens might compromise this protocol for preparation of cell vaccines.
Comparison of the Volatile Composition of Stachys persica Gmel. and Stachys byzantina C. Koch. Oils Obtained by Hydrodistillation and Steam Distillation
Authors: Khanavi Mahnaz , Hadjiakhoondi Abbas , Amin Gholamreza , Amanzadeh Yaghoob , Rustaiyan Abdolhossein , Shafiee Abbas 
Published: February 2015

Abstract
The oils obtained by hydrodistillation and steam distillation of the aerial parts of Stachys persica Gmel. and Stachys byzantina C. Koch grown in Iran were analyzed by GC/MS. The essential oil obtained by hydrodistillation of the aerial parts of S. persica was characterized by a high amount of non-terpenoid components of which methyllinoleate (27.7%), hexadecanoic acid (9.8%) and 6,10,14-trimethyl-2-pentadecanone (9.2%) were the major constituents, whereas the steam distilled oil of the plant contained hexadecanoic acid (27.2%), carvacrol (9.4%) and eugenol (5.2%).
Both hydrodistilled and steam distilled essential oils of the aerial parts of S. byzantina were rich in sesquiterpenes such as α-copaene (16.6% and 10.4%), spathulenol (16.1% and 18.5%) and β-caryophyllene (14.3% and 13.5%), respectively.
Antioxidant and Immunomodulatory Constituents of Henna Leaves
Authors: Mikhaeil Botros R. , Badria Farid A. , Maatooq Galal T. , Amer Mohamed M. A. 
Published: February 2015

Abstract
The immunomodulatory bioassay-guided fractionation of the methanolic extract of henna (Lawsonia inermis L.; syn. Lawsonia alba L.) leaves resulted in the isolation of seven compounds; three have been isolated for the first time from the genus, namely p-coumaric acid, 2-methoxy-3-methyl-1,4-naphthoquinone and apiin, along with the previously isolated compounds: lawsone, apigenin, luteolin, and cosmosiin. Structural elucidation of the isolated compounds was based upon their physical, chemical as well as spectroscopic characters. Their immuomodulatory profile was studied using an in vitro immunoassay, the lymphocyte transformation assay. The ABTS [2,2′-azino-bis (3-ethyl benzthiazoline-6-sulfonic acid)], free radical scavenging assay depicted that all isolated compounds exhibited antioxidant activity comparable to that of ascorbic acid.
Bioactivity of Lignans from Taxus baccata
Authors: Erdemoglu Nurgun , Sener Bilge , Choudhary M. Iqbal 
Published: February 2015

Abstract
Three lignan derivatives, (-)-taxiresinol (1), (-)-3′-demethylisolariciresinol-9′-hydroxyisopropylether (2) and (-)-3-demethylisolariciresinol (3), previously isolated from the heartwood of Taxus baccata L. (Taxaceae) were investigated for cytotoxicity against the Oncology Cell Line Panel (breast, colon, ovary, prostate, lung and a normal adult bovine aortic endothelial cell line) as well as for antimicrobial activities. Besides, a chloroform-soluble portion of the ethanol extract from the heartwood of T. baccata was also tested for antimicrobial activities. Compounds 1 - 3 did not demonstrate much cytotoxic potency according to the reference drug etoposide. With the exception of compound 2, the other two lignans (1 and 3) and the chloroform extract were shown to possess antifungal activity, whereas only the chloroform extract exhibited antibacterial activity against Pseudomonas aeruginosa
Binary Mixtures of (N-phosphonomethyl)-glycine with New Aminophosphonates
Authors: Bielecki Krzysztof , Sarapuk Janusz , Kleszczynáska Halina 
Published: February 2015

Abstract
The potential biological activity of binary mixtures of some new organophosphorous compounds, aminoalkane- and aminofluorenephosphonates, with (N-phosphonomethyl)-glycine (glyphosate, PMG) was studied. The inhibition of growth of wheat (Triticum aestivum) induced by individual compounds and their equimolar mixtures with PMG was a measure of that activity. The experiments were expected to show if the new compounds exhibited good biological activity to be used for agrochemical applications and if this activity can be improved when they are used in mixtures with glyphosate which is the active component of the well-known herbicide Roundup.
The results obtained show that aminofluorenephosphonates inhibited wheat growth when used in micromolar concentrations. Thus, their efficiency can be compared to that of PMG. The efficiency of aminoalkanephosphonates was one order of magnitude weaker. The measure of the efficiency was the effective concentration inhibiting wheat growth by 50% (EC50). The most demanded interaction, i.e., a synergistic was observed for only one of binary mixtures of the compounds studied with PMG. Mostly they showed antagonistic or strong antagonistic interactions. Some of them were of the additive type. Such results exclude the possibility of potential use of all the compounds studied in binary mixtures with phosphonomethylglycine, especially as the mentioned synergistic interaction found was rather weak. The influence of structural features of aminophosphonates on the results obtained is discussed.
Green Paramecia as an Evolutionary Winner of Oxidative Symbiosis: A Hypothesis and Supportive Data
Authors: Kawano Tomonori , Kadono Takashi , Kosaka Toshikazu , Hosoya Hiroshi 
Published: February 2015

Abstract
A single cell of the green paramecia (Paramecium bursaria) harbors several hundreds of endo-symbiotic Chlorella-like algae in its cytoplasm. Removal of algae from the host organism and re-association of ex-symbiotic host paramecia with ex-symbiotic algae can be experimentally demonstrated in the laboratory. However, the mechanism precisely governing the alga-protozoan association is not fully understood, and the origin of symbiosis in the evolutionary view has not been given. Here, we propose the possible biochemical models (models 1 and 2) explaining the co-evolution between Paramecium species and algal symbionts by pointing out that algal photosynthesis in the host paramecia plays a dual role providing the energy source and the risk of oxidative damage to the host. Model 1 lays stress on the correlation between the (re)greening ability of the paramecia and the tolerance to oxidative stress whereas model 2 emphasizes the cause of evolutionary selection leading to the emergence of Paramecium species tolerant against reactive oxygen species.
Rosmarinic Acid Synthesis in Transformed Callus Culture of Coleus blumei Benth
Authors: Bauer Nataša , Leljak-Levanic Dunja , Jelaska Sibila 
Published: February 2015

Abstract
Agrobacteria mediated Coleus blumei tumour tissues were cultured in vitro on MS medium. Sixteen diversified transformed callus cultures were maintained for several years in the absence of plant growth regulators and antibiotics without affecting the growth rate. Rosmarinic acid was detected spectrophotometrically in all tissue lines but in different quantities. The highest rosmarinic acid accumulation detected was 11% of dry tissue mass. The relation between culture growth and rosmarinic acid production was investigated in three callus lines. The lines showed different rosmarinic acid accumulation in relation to their growth rate; it was either parallel or inversely related to the tissue growth. The effects of certain medium constituents on the callus growth and rosmarinic acid accumulation were examined in four tumour cell lines. Addition of 4% or 5% sucrose stimulated rosmarinic acid synthesis and decreased callus growth. Nitrogen reduction to one half or one quarter of initial concentration did not affect rosmarinic acid synthesis and decreased callus growth in three lines, while it increased rosmarinic acid accumulation and callus growth in one line. Addition of 0.1 mg/l Phe stimulated rosmarinic acid production in two lines but had little effect on the rosmarinic acid level in others. Rosmarinic acid production was significantly improved on modified macronutrients, where the Ac2 line produced 16.5 mg of rosmarinic acid per tube (0.2 g of dry wt) after being in culture for 35 days.
Cloning and Sequencing of Hydroxylase Genes Involved in Taxol Biosynthesis
Authors: Tu Jun , Zhu Ping , Cheng Ke-di , Meng Chao 
Published: February 2015

Abstract
Two full-length cDNAs (TCH1 and TCH2) were obtained from a cDNA library of Taxus chinensis mainly by the single specific-primer PCR (SSP-PCR) method. Compared with other reported enzymes from Taxus species, the deduced amino acid sequences of TCH1 and TCH2 exhibit significant homologies to hydroxylases that are involved in taxol biosynthesis. These findings imply that the two new genes are closely related to the biosynthesis of taxol/taxoids.
A Serine Protease from a Detergent-soluble Extract of Leishmania (Leishmania) amazonensis
Authors: Silva Lopez Raquel Elisa da , De Simone Salvatore Giovanni 
Published: February 2015

Abstract
Proteases mediate important crucial functions in parasitic diseases, and their characterization contributes to the understanding of host-parasite interaction. A serine protease was purified about 43-fold with a total recovery of 60% from a detergent-soluble extract of promastigotes of Leishmania amazonensis. The purification procedures included aprotinin-agarose affinity chromatography and gel filtration high performance liquid chromatography. The molecular mass of active enzyme was 110 kDa by native gel filtration HPLC and by SDSPAGE gelatin under non-reducing conditions. Under conditions of reduction using SDSPAGE gelatin analyses the activity of enzyme was observed in two proteins of 60 and 45 kDa, suggesting that the enzyme may be considered as a dimer. The Leishmania protease was not glycosylated, and its isoelectric point (pI) was around 4.8. The maximal protease activity was at pH 7.0 and 28 °C, using α-N-ᵨ-tosyl-ʟ-arginyl-methyl ester (ʟ-TAME) as substrate. Assays of thermal stability indicated that this enzyme was totally denatured after pre-treatment at 42 °C for 12 min and preserved only 20% of its activity after pre-treatment at 37 °C for 24 h, in the absence of substrate. Hemoglobin, bovine serum albumin (BSA), ovalbumin and gelatin were hydrolyzed by Leishmania protease. Inhibition studies indicated that the enzyme belonged to a serine protease class because of a significant impediment by serine protease inhibitors such as benzamidine, aprotinin, and antipain. The activity of the present serine protease is negatively modulated by calcium and zinc and positively modulated by manganese ions. This is the first study that reports the purification of a protease from a detergent-soluble extract of Leishmania species.
Total, Free and Conjugated Sterolic Forms in Three Microalgae Used in Mariculture
Authors: Mohammady Nagwa Gamal 
Published: February 2015

Abstract
Total, free and conjugated forms (steryl esters, steryl glycosides and acyl steryl glycosides) of sterols from three microalgae that are extensively used in mariculture (Tetraselmis chuii, Nannochloropsis salina and Skeletonema costatum) were examined. The results revealed that cholesterol is the only common fraction detected in all investigated species and distributed in free and all conjugated forms. However, the total sterol content of T. chuii was about 325 μg/g dry wt, most of it was concentrated amongst 24-methylcholesta-5,24-diene-3β-ol and 24-methylcholest-5-en-3β-ol. On the other hand, the majority of the fractions were distributed in the free form. The total sterol content of N. salina was about 180 μg/g dry wt, cholesterol was the major fraction that was detected. Nevertheless, the dominant distribution forms were esterified. While in S. costatum, the total sterol content was 76 μg/g dry wt, approximately most fractions are quantitatively alike and dominated in the free form. Furthermore, our study shows clearly that most sterols are not distributed regularly within each form, a result that encouraged us to suggest a distribution of specific sterol fraction as a free or conjugated can be used as a serving tool in chemotaxonomic studies.
Separation of Flavonoids from Aleurites moluccana Leaves Using Chitosan Modified with Heptaldehyde
Authors: Morsch Michele , Girardi Leury G. J. , Cechinel-Filho Valdir , Meyre-Silva Christiane , Rodrigues Clóvis Antonio 
Published: February 2015

Abstract
Heptaldehyde-modified chitosan (heptyl-chitosan, CH-Hp) was investigated as adsorbent for chromatograhic separation of the flavonoids from A. moluccana. The amount of 2″-Orhamnosylswertisin isolated (30.0 mg) was approx. twice as high as swertisin (17.5 mg). The improved surface hydrophobicity effected by the heptyl groups promoted the separation of flavonoids. From the results obtained, CH-Hp seems to be more suitable for separation of glycosylated flavonoids than other flavonoids. Thus, modified chitosan described here can be used for hydrophobic interaction chromatography as sucessfully illustrated with flavonoids.
The Influence of Growth Regulators on Membrane Permeability in Cultures of Winter Wheat Cells
Authors: Filek Maria , Biesaga-Kościelniak Jolanta , Marcińsk Izabela , Machačková Ivana , Krekule Jan 
Published: February 2015

Abstract
The effect of plant growth substances (IAA, 2,4-D, zeatin, kinetin, zearalenone) were studied on membrane properties of the cells of embryogenic (E) and non-embryogenic (NE) calli derived from immature inflorescences (inf) or embryos (emb) of winter wheat. Calli initiated from inflorescences show higher permeability. The ion leakage from cells of E calli was higher than from cells of NE calli. Growth regulators were used in concentrations of 2-30 mg/l (about 10-140 μm). All tested growth substances increased ion leakage from NE emb cells, IAA, zeatin and kinetin being most effective. In NE inf cells the effect of growth substances was similar as in NE emb, but much weaker. In E cells of both types (inf and emb) growth substances decreased ion leakage. Changes in the leakage of potassium and calcium ions were similar to those in total ion leakage. The uptake of labelled auxins (IAA and 2,4-D) was higher in NE cells (especially in NE inf) than in E cells. The endogenous level of IAA was higher in E cells than in NE cells and in inf cells than in emb cells. The importance of auxin in determining permeability of cell membranes is discussed.
Effect of Photon Flux Density and Temperature on the Production of Halogenated Monoterpenes by Plocamium cartilagineum (Plocamiaceae, Rhodophyta)
Authors: Palma Rodrigo , Edding Mario , Rovirosa Juana , San-Martín Aurelio , Argandoña Victor H. 
Published: February 2015

Abstract
The effect of different photon flux densities (PFD) and temperatures on the relative growth rate (RGR) and the concentration of three halogenated monoterpenes in samples of Plocamium cartilagineum L.( Dixon), a marine alga (Rhodophyceae), were studied. The highest RGR (22.8 ± 0.04 d-1) was obtained at 15 °C and 41 μmol m-2 s-1 of PFD and the lowest (18.0 ± 0.2 d-1) was obtained at 18 °C and 120 μmol m-2 s-1. The different temperatures and light used in assays did not affect significantly the production of organic compounds. The production of mertensene and violacene was not affected significantly. However, compound 1 reached the highest concentration at 15 °C and 65 μmol m-2 s-1. The relationship between growth and production of monoterpenes of P. cartilagineum and the effect of temperature and the PFD were analyzed.
Microsomal Detoxification Enzymes in Yam Bean [Pachyrhizus erosus (L.) Urban]
Authors: Belford Ebenezer J. D. , Dörfler Ulrike , Stampf Andreas , Schröder Peter 
Published: February 2015

Abstract
Cytochrome P450s and glutathione-S-transferases (GSTs) constitute two of the largest groups of enzyme families that are responsible for detoxification of exogenous molecules in plants. Their activities differ from plant to plant with respect to metabolism and substrate specificity which is one of the reasons for herbicide selectivity. In the tuber forming yam bean, the legume Pachyrhizus erosus, their activities at the microsomal level were investigated to determine the detoxification status of the plant. The breakdown of the herbicide isoproturon (IPU) to two distinct metabolites, 1-OH-IPU and monodesmethyl-IPU, was demonstrated. GST activity was determined with model substrates, but also by the catalysed formation of the fluorescent glutathione bimane conjugate. This study demonstrates for the first time microsomal detoxification activity in Pachyrhizus and the fluorescence image description of microsomal GST catalysed reaction in a legume.
Interactions of Calf Spleen Purine Nucleoside Phosphorylase with 8-Azaguanine, and a Bisubstrate Analogue Inhibitor: Implications for the Reaction Mechanism
Authors: Wierzchowski Jacek , Bzowska Agnieszka , Stępniak Katarzyna , Shugar David 
Published: February 2015

Abstract
Interactions of calf spleen purine nucleoside phosphorylase (PNP) with a non-typical substrate, 8-azaguanine (8-azaG), and a bisubstrate analogue inhibitor, 9-(2-phosphonylmethoxyethyl)- 8-azaguanine (PME-azaG), were investigated by means of steady-state fluorescence spectroscopy. Both 8-azaG and PME-azaG form fluorescent complexes with the enzyme, and dissociation constants are comparable to the appropriate parameters (Km or Ki) obtained from kinetic measurements. PME-azaG inhibits both the phosphorolytic and synthetic pathway of the reaction in a competitive mode. The complex of 8-azaG with PNP is much weaker than the previously reported Gua-PNP complex, and its dissociation constant increases at pH > 7, where 8-azaG exists predominantly as the monoanion (pKa ≈ 6.5). The fluorescence difference spectrum of the PNP/8-azaG complex points to participation of the N(7)H or/and N(8)H tautomers of the neutral substrate, and the 9-(2-phosphonylmethoxyethyl) derivative also exists as a neutral species in the complex with PNP. The latter conclusion is based on spectral characteristics of the PNP/PME-azaG complex, confirmed by fluorimetric determination of dissociation constants, which are virtually pH-independent in the range 6-7. These findings testify to involvement of the neutral purine molecule, and not its monoanion, as the substrate in the reverse, synthetic reaction. It is proposed that, in the reverse reaction pathway, the natural purine substrate is bound to the enzyme as the neutral N(7)H tautomer, which is responsible for the reported strong fluorescence of the guanine-PNP complex.
Pigments and Citrinin Biosynthesis by Fungi Belonging to Genus Monascus
Authors: Pisareva Emiliya , Savov Valentin , Kujumdzieva Anna 
Published: February 2015

Citrinin is a mycotoxin, which is produced by fungi belonging to the genus Monascus, known in biotechnology as producers of azaphilone pigments. The relation between biosynthesis of these secondary metabolites was investigated in different species of the genus Monascus in batch-culture at the following cultivation conditions: T = 28 °C, agitation 220 rpm, and a medium, which induce citrinin production, containing ethanol as a carbon source.
The screening was carried out with 16 fungal strains and the biosynthesis of citrinin and pigments was monitored quantitatively at the standard conditions mentioned above. Some kinetic parameters of the process have been determined. The values of the growth yield coefficient YX/C were between 0.32 and 0.57. The amount of the extracellular red and orange pigments at the end of cultivation varied for the different strains between 0.09 and 1.33 OU/ mg dry weight, and 0.15 and 0.96 OU/mg dry weight, respectively. The amount of the total pigments measured was between 0.16 and 3.6 OU/mg dry weight, and between 0.21 and 3.39 OU/mg dry weight. The determined ratio 500 nm/400 nm, characterizing the pigment production, ranged between 0.60 and 1.06. Twelve of the investigated strains produced citrinin and pigments, two of them produced only pigments. Two strains were not able to produce neither pigments nor citrinin.
Thus, the biosynthesis of citrinin appeared to be strain-specific and does not correlate with the pigments’ biosynthesis by the fungal strains belonging to the genus Monascus.
A Ligand Function of Glutathione S-Transferase
Authors: Lederer Barbara , Böger Peter 
Published: February 2015

Abstract
Glutathione S-transferases (GSTs) are ubiquitous enzymes and abundant in plants. They are intimately involved in plant metabolism and stress defense related to reactive oxygen species. Our project assigned particular reactions including novel ones to certain GST-isoforms. Transformed E. coli was used to express recombinant GST-isoforms from maize. An N-terminal His tag allowed their purification by affinity chromatography. Three GST-monomers had a molecular weight of 26, 27, 29 kDa, and aggregated to dimers when assayed for their enzymic properties. Four dimeric isoforms were used to study how they interact with tetrapyrroles (of the chlorophyll biosynthesis pathway). It was found that protoporphyrin IX (Proto IX), Mg-protoporphyrin and other tetrapyrroles are bound non-covalently (“liganded”) to GSTs but not conjugated with reduced glutathione. This binding is non-covalent, and results in inhibition of conjugation activity, the degree depends on type of the porphyrin and GST-isoform. I50-values between 1-10 μᴍ were measured for Proto IX, the inhibition by mesoporphyrin and Mg-protoporphyrin was 2- to 5-fold less. The ligand binding is noncompetitive for the substrate 1-chloro-2,4-dinitrobenzene and competitive for glutathione. The dimer GST 26/26 prevents the (non-enzymic) autoxidation of protoporphyrinogen to Proto IX, which produces phytotoxic reactive oxygen species in the light. GST 27/27 protects hemin against degradation. Protoporphyrinogen is formed in the plastid and then exported into the cytosol. Apparently binding by a suitable GST-isoform ensures that the highly autoxidizable protoporphyrinogen can safely reach the mitochondrium where it is processed to cytochrome.