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111.
The growth capability of Trichoderma harzianum Rifaii Tl was tested on Malt Extract and Czapeks Dox agar containing different concentrations of Cu2+, Zn2+, Mn2+, Fe2+ and Ca2+. The T. harzianum Tl isolate was observed to produce mycelia and spores in various mineral-containing media. It showed the lowest tolerance
to Ca2+ and the highest tolerance to Fe2+. Solubilization capability of T. harzianum Tl for some insoluble minerals via acidification of medium has been tested on MnO2, CuO, Fe2O3 and metallic Zn. T. harzianum Tl was able to solubilize MnO2 and metallic Zn in a liquid medium. 相似文献
112.
113.
Seda Karasu Yalçin Zekiye Yeşim Özbaş 《World journal of microbiology & biotechnology》2005,21(6-7):1303-1310
Summary Glycerol has been known as an important by-product of wine fermentations improving the sensory quality of wine. This study
was carried out with an endogenic wine yeast strain Saccharomyces cerevisiae Kalecik 1. The kinetics of growth and glycerol biosynthesis were analysed at various initial concentrations of glucose, fructose,
and sucrose in a batch system. Depending on the determined values of Monod constants, glucose (Ks = 28.09 g/l) was found as the most suitable substrate for the yeast growth. Initial glucose, fructose and sucrose concentrations
necessary for maximum specific yeast growth rate were determined as 175 g, 100 l, and 200 g/l, respectively. The yeast produced
glycerol at very high concentrations in fructose medium. Fructose was determined as the most suitable substrate for glycerol
production while the strain showed low tendency to use it for growth. S. cerevisiae Kalecik 1 could not produce glycerol below 200 g/l initial sucrose concentration. When natural white grape juice was used
as fermentation medium, maximum glycerol concentration and dry weight of the yeast were determined as 9.3 g/l and 11.8 g/l,
respectively. 相似文献
114.
Pelin Aribal Kocatürk M. Cenk Akbostanci Canan Işikay Aylin Öcal Deniz Tuncel Güzin Özelçi Kavas Nermin Mutluer 《Biological trace element research》2001,80(2):115-124
Ischemia is associated with the pathological changes caused by the accumulation of reactive oxygen metabolites (ROM) in cerebrovascular
accident (CVA). The aim of this study was to determine red cell copper/zinc-superoxide dismutase (Cu/Zn-SOD) and catalase
activities and copper and zinc concentrations both in plasma and in red cells in CVA. Cu/Zn-SOD and catalase activities of
16 patients, with an average age of 64 yr, were measured spectrophotometrically; copper and zinc concentrations were determined
by atomic absorption spectrophotometer. The results showed that Cu/Zn-SOD activity was increased markedly in patients compared
to the young controls and reached a peak on the d 5 of the disease, whereas the catalase activity of the patients on d 3 and
d 5 were in the normal range, but higher on d 10. The enzyme activities of the elderly group were generally increased compared
to the young controls. Copper and zinc concentrations showed corresponding alterations. These findings suggested that the
effects of oxidative stress in CVA might be reflected in red cell and plasma parameters.
Presented at the III International Congress of Pathophysiology, Lahti, Finland, 28 June–3 July, 1998. 相似文献
115.
Ramazan Çakmakçı Mesude Figen Dönmez Yaşar Ertürk Mustafa Erat Ayhan Haznedar Remzi Sekban 《Plant and Soil》2010,332(1-2):299-318
The purpose of this study was to investigate the diversity of cultivable phosphate solubilising (PSB) and total bacteria originated from 384 rhizospheric acidic soils samples of tea plants grown at 32 locations. Over 900 rhizoplane bacteria were randomly selected from agar-solidified trypticase soy broth, and identified using fatty acid methyl ester (FAME) profiles. Based on FAME profiles, 53 bacterial genera were identified with a similarity index >0.3, but 60.3% of the identified isolates belonged to five genera: Bacillus (34.6%), Pseudomonas (8.9%), Stenotrophomonas (6.1%), Paenibacillus (5.9%) and Arthrobacter (4.8%). The bacilli group comprised many different species, with the most abundant being B. cereus, B. megaterium and B. sphaericus. The main identified Pseudomonads included P. fluorescens, P. putida, and P. alcaligenes. About 30.4% of the bacterial isolates could not be classified to genus since their similarity indices were <0.3 indicating no close matches. Most of the total and P-solubilizing bacteria isolated were Gram positive (61.3 and 52.3%), and Gram negative constituted only 38.7 and 47.7%. Out of the 214 PSB from a pool of 506 bacterial isolates recovered on the selective media from the rhizosphere of tea, 74 of them were characterized by carbon sources using BIOLOGM GN2 and GP2 plates. Bacillus, Pseudomonas, Paenibacillus and Stenotrophomonas genera were the most prominent P-solubilizing groups in the rhizosphere and soil populations analyzed. B. cereus, P. fluorescens, S. maltophilia, B. megaterium, P. putida, B. sphaericus and Paenibacillus polymyxa were the most frequent P-solubilizing species in the acidic tea rhizosohere soils. Selected Gram-positive PSB appeared to favour carbohydrates, and Gram-negative bacteria appeared to favour carboxylic acids, amino acids and carbohydrates as carbon sources. Selected phosphate solubilizing acid tolerant strains showed high variability in utilizing various carbon sources. 相似文献
116.
Different types of genetic and epigenetic changes are associated with HNSCC. The molecular mechanisms of HNSCC carcinogenesis are still undergoing intensive investigation. WWOX gene expression is altered in many cancers and in a recent work reduced WWOX expression has been associated with miR-134 expression in HNSCC. In this study we investigated the WWOX messenger RNA expression levels in association with the promoter methylation of the WWOX gene and miR-134 expression levels in 80 HNSCC tumor and non-cancerous tissue samples. Our results show that WWOX expression is down-regulated especially in advanced-stage tumor samples or in tumors with SCC. This down-regulation was associated with methylation of the WWOX promoter region but not with miR-134 expression. There was an inverse correlation between the expression level and promoter methylation. We also analyzed whole exons and exon/intron boundries of the WWOX gene by direct sequencing. In our study group we observed 10 different alterations in the coding sequences and 18 different alterations in the non-coding sequences of the WWOX gene in HNSCC tumor samples. These results indicate that the WWOX gene can be functionally inactivated by promoter methylation, epigenetically or by mutations affecting the sequences coding for the enzymatic domain of the gene, functionally. We conclude that inactivation of WWOX gene contributes to the progression of HNSCC. 相似文献
117.
The title compound, 2-{4-[3-(2,5-dimethylphenyl)-3-methylcyclobutyl]thiazol-2-yl}isoindoline-1,3-dione (C24H22N2O2S), was synthesized and characterized by IR-NMR spectroscopy and single-crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P21/c with a?=?19.7799(13) Å, b?=?6.7473(4) Å, c?=?15.7259(9) Å and β?=?103.416(5)°. In addition, the molecular geometry, vibrational frequencies and gauge including atomic orbital (GIAO) 1H and 13C chemical shift values of the title compound in the ground state have been calculated by using the Hartree-Fock (HF) and density functional method (DFT/B3LYP) with 6–31G(d), 6–31 + G(d,p) and LANL2DZ basis sets, and compared with the experimental data. To determine conformational flexibility, molecular energy profile of the title compound was obtained by semi-empirical (AM1) calculations with respect to two selected degrees of torsional freedom, which were varied from ?180° to +180° in steps of 5°. Besides, molecular electrostatic potential, frontier molecular orbitals (FMO) analysis and thermodynamic properties of the title compound were investigated by theoretical calculations. 相似文献
118.
Mustafa Serkan Abdusselam Selcan Kilis Çiğdem Şahin Çakır Zennure Abdusselam 《Science activities》2018,55(1-2):68-74
As a fundamental strategy for all science curriculum, inquiry is of prime importance. In order to facilitate inquiry during science education in middle school, 5E learning model was applied in this study. Following 5E learning model during a lesson, students can engage in a topic after being served to mitigate cognitive disequilibrium or familiar with daily-life examples such as yoghurt fermentation, oven spring, etc. explore the topic making an observation or testing hypothesis, explain and relate their experiences scientifically, extend or elaborate their knowledge and then being evaluated. This study introduces a sample 5E learning model for middle school students at the ages of 10–12 in science laboratory with an augmented reality microscope MicrosAR to examine microscopic organisms based on inquiry-based learning. 相似文献
119.
Aysun Çapcı Karagöz Christoph Reiter Ean-Jeong Seo Lisa Gruber Friedrich Hahn Maria Leidenberger Volker Klein Frank Hampel Oliver Friedrich Manfred Marschall Barbara Kappes Thomas Efferth Svetlana B. Tsogoeva 《Bioorganic & medicinal chemistry》2018,26(12):3610-3618
Hybridization of natural products has high potential to further improve their activities and may produce synergistic effects between linked pharmacophores. Here we report synthesis of nine new hybrids of natural products egonol, homoegonol, thymoquinone and artemisinin and evaluation of their activities against P. falciparum 3D7 parasites, human cytomegalovirus, sensitive and multidrug-resistant human leukemia cells. Most of the new hybrids exceed their parent compounds in antimalarial, antiviral and antileukemia activities and in some cases show higher in vitro efficacy than clinically used reference drugs chloroquine, ganciclovir and doxorubicin. Combined, our findings stress the high potency of these hybrids and encourages further use of the hybridization concept in applied pharmacological research. 相似文献
120.
Abdelbasset?ChafikEmail author Abdelkhalid?Essamadi Safinur?Yildirim??elik Kübra?Solak Ahmet?Mavi 《Russian Journal of Bioorganic Chemistry》2018,44(1):41-51
Climate change and increasing temperatures are global concerns. Well adapted to desert life, the camel (Camelus dromedarius) lives most of its life under high environmental stress and represents an ideal model for studying desert adaptation among mammals. Glutathione peroxidase is the principal antioxidant defense system capable of protecting cells from oxidative stress. Glutathione Peroxidase from camel liver was purified (11.64-fold purification with 1.73% yield) and characterized The molecular weight of the enzyme was estimated to be about 69 kDa by gel filtration and 34 kDa by SDS-PAGE, implying dimeric structure of the protein. An optimum temperature of 47°C and an optimum pH of 7.8 were found. This enzyme is a typical SH-enzyme that is inhibited by D,L-dithiothreitol and β-mercaptoethanol and sensitive to bivalent cations. The enzyme had common specificity toward hydroperoxides and high specificity for reduced glutathione. The Km and Vmax values for hydrogen peroxide and reduced glutathione were 0.57 and 2.10 mM and 1.11 and 0.87 U/mg, respectively. The purified enzyme contained 16 ng of selenium per mg of protein. Our results show that the camel glutathione peroxidse exhibits properties different of those reported for other mammalian species. Lower molecular weight, homodimeric structure, higher optimum temperature, relatively low optimum pH, high affinity for hydrogen peroxide at low concentration of reduced glutathione and very low content of selenium could be explained by adaptation of the camel to living in the desert under intense environmental stress. 相似文献