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First Report of Tumorigenic Agrobacterium radiobacter on Raspberry in Serbia
Svetlana Milija?evi?,Veljko Gavrilovi?,Svetlana ?ivkovi?,Nenad Trkulja
Pesticidi i Fitomedicina , 2007,
Abstract: During the spring of 2003, gall symptoms on the roots and crowns of young raspberry plants cv. Vilamette were observed near Valjevo. Phytopathogenic bacteria were isolated from diseased plant samples. Based on the pathogenic, morphological, differential biochemicaland physiological characteristics, the isolated strains were identified as tumorigenic Agrobacterium radiobacter (biovar 1 Agrobacterium). In order to confirm the identity of isolated strains by polymerase chain reaction (PCR) primers complementary to tms2 genelocated on the Ti plasmid were used. In the first PCR protocol using a tms2F1 + tms2R2 primer pair, 617 bp products specific for tumorigenic Agrobacterium strains were amplified. The second PCR protocol, using a tms2F1 + tms2B primer pair, amplified the expected 458 bp products. On the basis of multiplex PCR with primers complementary to chromosomal gene coding for 23S rRNA, the isolated strains were classified as biovar 1 Agrobacterium (A. radiobacter). This is the first report of tumorigenic A. radiobacter on raspberry in Serbia.
Modeling of D-Hydantoinase Production by Agrobacterium radiobacter in a Batch System  [PDF]
M. Annamalai,Mukesh Doble
Journal of Applied Sciences , 2007,
Abstract: Mathematical modeling of hydantoinase production system from microbial sources, which would help to understand the mechanism of the process, has not been attempted earlier. This paper tries to model five state variables (biomass, substrate, product (D-hydantoinase), Oxygen Uptake Rate (OUR) and carbon dioxide production rate (CPR)) for three carbon sources namely glucose, glycerol and maltose in the production of D-hydantoinase using Agrobacterium radiobacter as source. Several models were tested to fit the aerobic batch experimental data from a 3 L bioreactor. The best fitting model consisted of (a) biomass growth non-linearly dependent on substrate concentration, (b) product formation rate following exponential form of product inhibition and (c) OUR following positive regulation by substrate. D-hydantoinase production in maltose experiences minimal lag phase and stronger product inhibition when compared to glycerol. Maltose showed higher biomass yield (0.25) and specific D-hydantoinase production (27.44 U mg-1) compared to glycerol whose values are 0.18 and 21.97 U mg-1, respectively.
In vitro and in vivo toxicity studies of Agrobacterium radiobacter k84 biopolymer (ARB) Estudos in vitro e in vivo de toxicidade de biopolímero de Agrobacterium radiobacter k84 (ARB)  [cached]
Caroline Maria Calliari,Marciane Magnani,Alexandre Ykuio Saito,Pedro Sebasti?o Dionízio Filho
Semina : Ciências Agrárias , 2011,
Abstract: Sugar cane molasses is a cheaper carbon source alternative than glucose traditionally used in fermentation processes. In the present study a biopolymer soluble from Agrobacterium radiobacter k84 (ARB) was obtained by fermentation using sugar cane molasses as a carbon source in a process with yield of 10.0 g.L-1. The ARB is composed by minerals (40%), carbohydrate (35%) and protein (15%). In vitro test of the cytotoxic effect of ARB at concentrations 2.5 mg/mL, 5.0 mg/mL and 10.0 mg/mL in LLC MK2 (Rhesus Monkey Kidney) cells revealed a 50% cytotoxic concentration (CC50) of 9.32 mg/mL. In a 30-day in vivo oral toxicity study, Swiss mice were administered ARB by gavage at 5 mg/mL, 15 mg/mL, 50 mg/mL and 150 mg/mL (approximately 25 mg/kg/day, 75 mg/kg/day, 250 mg/kg/day and 750 mg/kg/day). The results did not present any hematological or histopathological signs of adverse effects, leading us to define the no observed adverse effect level (NOAEL) as 150 mg/mL (approximately 750 mg/kg/day). O mela o de cana-de-a úcar é uma fonte de carbono alternativa de menor custo que a glicose tradicionalmente utilizada em processos fermentativos. No presente estudo, um biopolímero solúvel de Agrobacterium radiobacter k84 (ARB) foi obtido por fermenta o utilizando mela o de cana de a úcar como fonte de carbono em um processo com rendimento de 10,0 g.L-1. O ARB é composto de minerais (40%), carboidratos (35%) e proteínas (15%). O teste do efeito citotóxico do ARB in vitro nas concentra es de 2,5 mg/mL, 5,0 mg/mL e 10,0 mg/mL em células LLC MK2 (Rim de Macaco Rhesus) revelou uma concentra o citotóxica 50% (CC50) de 9,32 mg/mL. Em estudo in vivo de toxicidade oral durante 30 dias, camundongos Swiss receberam por gavagem solu es de ARB nas concentra es de 5 mg/mL, 15 mg/mL, 50 mg/mL e 150 mg/mL (aproximadamente 25 mg/kg/dia, 75 mg/kg/dia, 250 mg/ kg/dia e 750 mg/kg/dia). Os resultados n o apresentaram sinais hematológicos ou histopatológicos de efeitos adversos, levando a definir a dose sem efeito adverso observado (NOAEL) como 150 mg/mL (aproximadamente 750 mg/kg/dia).
Production, characterization and technological properties of biopolymer produced by Agrobacterium radiobacter k84 Produ o, caracteriza o e propriedades tecnológicas de um biopolímero produzido por Agrobacterium radiobacter k84  [cached]
Caroline Maria Calliari,Marciane Magnani,Raúl Jorge Hernan Castro Gómez
Semina : Ciências Agrárias , 2011,
Abstract: In this study, a biopolymer composed of carbohydrates (35%), protein (15%) and minerals (40%) was obtained through fermentation using sugar cane molasses as the sole carbon source for Agrobacterium radiobacter k84. The process yield was 10 gL-1 of biopolymer, which showed high solubility in water, neutral pH in aqueous solution and low water activity (0.52). The analysis in Scanning Electron Microscopy revealed microstructure characteristic of an amorphous solid, with particles of irregular shapes and sizes. In the evaluation of technological properties, the biopolymer showed formation of viscous solutions at room temperature from concentration of 0.5% in aqueous solution, gelling activity in solution at 2%, emulsifying (56.11±1.39%) and stabilizing activity (98.02±0.78%). The results suggest that the biopolymer from Agrobacterium radiobacter k84 is a promising candidate for industrial use. No presente estudo, utilizando mela o de cana-de-a úcar como única fonte de carbono para Agrobacterium radiobacter k84 foi obtido, em processo fermentativo, um biopolímero composto por carboidratos (35%), proteínas (15%) e minerais (40%). O rendimento do processo foi de 10 g.L-1 do biopolímero que apresentou elevada solubilidade em água, pH neutro em solu o aquosa e baixa atividade de água (0.52). As análises em Microscopia Eletr nica de Varredura revelaram microestrutura característica de um sólido amorfo, com partículas de formas irregulares e tamanhos variáveis. Na avalia o das propriedades tecnológicas, o biopolímero mostrou viscosidade à temperatura ambiente a partir da concentra o 0.5% em solu o aquosa, atividade geleificante em solu o a 2%, atividade emulsificante (56.11±0.78%) e estabilizante (98.02±1.39%). Os resultados sugerem o biopolímero de Agrobacterium radiobacter k84 como um candidato promissor para uso industrial.
Avalia??o da mutagenicidade e antimutagenicidade de um biopolímero extraído do microorganismo Agrobacterium radiobacter em camundongos Swiss
Primo, Milka Selestina;Calliari, Caroline Maria;Castro-Gómez, Raúl Jorge Hernan;Mauro, Mariana de Oliveira;Mantovani, Mário Sérgio;Oliveira, Rodrigo Juliano;
Revista Brasileira de Farmacognosia , 2010, DOI: 10.1590/S0102-695X2010000300009
Abstract: this study evaluated the mutagenic and ant mutagenic action of a biopolymer of glucose extracted from agrobacterium radiobacter (biopolymer of agrobacterium radiobacter). the experiment was conducted with swiss male mice divided into eight groups. treatment with the biopolymer was performed in a single dose by gavage at a dose of concomitant phosphate buffer groups in the evaluation of mutagenicity, or the agent of inducing dna damage, cyclophosphamide, the concentration of 50 mg/kg (body weight --b.w.), in groups of assessment ant mutagenic. we used the micronucleus test in peripheral blood. the blood sample was held 24 and 48 h after application of the test substances. statistical analysis showed that the biopolymer has no mutagenic activity and it is effective in preventing damage to dna. the percentages of damage reduction in groups of ant mutagenic were 83.9%, 89.1% and 103.1% in 24 h and 101.24%, 98.14% and 120.64% at doses of 48 to 75, 150 and 300 mg/kg (b.w.) respectively. the high percentage of damage reduction associated with the absence of mutagenic effects indicates the possibility of biopolymer chemoprotection action. it can also be considered a functional food candidate to be used as co-adjuvant chemotherapy to prevent side effects.
Influence of Uracil in Fermentation Media on β-Glucan Production by Agrobacterium Radiobacter A 1.5 and Agrobacterium sp. Bro 1.2.1
Kusmiati,Salmah Muhamad,Sukma Nuswantara,Swasono R.Tamat
Makara Seri Sains , 2007,
Abstract: Optimum β-glucan production can be achieved by an optimum condition in the fermentation media. Uracil, as a precursor of UDP-glucose, may act as a glucose donor in the formation of polysaccharides such as β-glucan. It is expected that addition of certain quantity of uracil into the fermentation media in a suitable growth phase of Agrobacterium radiobacter A 1.5 and Agrobacterium sp. Bro 1.2.1, will significantly increase the β-glucan production. In this investigation, 0.025%; 0.05% or 0.1% of uracil were added into the fermentation media during the logarithmic phase (24 hour) or stationary phase (46 hour) of growth. The β-glucan product was evaluated from the β-glucan (crude) dry-weight and from the β-glucan content. Beta-glucan content was determined as glucose by the Hisamatsu-AOAC and HPLC methods. The highest β-glucan (crude) dry-weight produced by the A. 1.5 was in a medium containg 0.025% uracil (24 hour), whilst by the A. Bro 1.2.1 was in a medium containg 0.1% uracil (46 hour), both higher than control. The highest β-glucan content produced by the A. 1.5 (27.03%) was in a medium containg 0.025% uracil (46 hour), while control produced only 23.28%. The highest β-glucan content produced by the Bro 1.2.1 (29.34%) was in a medium containg 0.025% uracil (24 hour), while control produced only 28.75%. Two-way anova analysis showed that there were no significant influence difference (α = 0,05) from various concentration of uracil in either growth phases, to the yield of β-glucan (crude) dry-weight nor to the β-glucan equivalent glucose content.
Peritonitis due to Rhizobium radiobacter  [PDF]
Raquel Marta,Catarina Damaso,José Esteves da Silva,Margarida Almeida
Einstein (S?o Paulo) , 2011,
Abstract: Rhizobium radiobacter (Agrobacterium radiobacter) is an aerobicGram-negative rod belonging to Agrobacterium genus, a groupof phytopathogenic bacteria present in the soil that has beenimplicated in human opportunistic infections. We report a clinicalcase of bacterial peritonitis in a 5-year-old child with chronic renaldisease in peritoneal dialysis, who had a history of direct soilcontact identified. The infection was treated with ceftazidime andpiperaciline+tazobactam without relapses or the need to remove theperitoneal dialysis catheter.
Decolourisation of Crystal Violet and Malachite Green By Fungi
B Moturi, MA Singara Charya
Science World Journal , 2009,
Abstract: Decolourisation of crystal violet and malachite green by white rot fungi, Polyporus elegans, Trametes versicolor, Lenzites betulina and soil fungus Mucor mucedo isolated from dye effluent amended soils was studied. There was no toxic effect of crystal violet on the growth of the four fungi but malachite green showed retardation of growth. Mucor mucedo decolourised 78% of the crystal violet and 65% of malachite green. The white rot fungi showed more than 60% decolourisation of crystal violet and 26 to 57% decolourisation of malachite green. In the process of decolourisation, lignin peroxidase production was high at 15 days incubation by all the organisms. Manganese peroxidase was secreted more after 10 days of incubation and laccase production was high after 15 days of incubation by Polyporus elegans and Trametes versicolor and after 10 days in the case of Lengites betulina. Mucor mucedo failed to secrete manganese peroxidase and laccase in all its incubations.


中国物理 B , 1995,
Abstract: The adsorption kinetica of crystal violet (CV) on silver mirror and two different kinds of silver sols is studied. The adsorption of CV on silver is homogeneous. It is confirmed that the topography of the surface affects only adsorption rate constant, while it does not change heterogeneity parameter. The similar behavior of enhancement factor and adsorption rate constant of CV in the two silver sols is discussed. The adsorption energy of CV and the concentration of adsorbed sites on the surface are estimated by adsorption isotherm. It is found that the enhancement effect on the silver mirror is determined by the concentration of adsorbed sites on surface.
Some notions about sehr spectra of crystal violet  [PDF]
A. M. Polubotko,V. P. Smirnov
Physics , 2010,
Abstract: The paper presents our opinion on the investigations and results of various kind of vibrational spectra of crystal violet (CV). After our analysis of the published spectra we came to conclusion, that the assignment of vibrations in this molecule remains questionable. Some experimental and calculations data permit us to conclude, that the vibrational bands in the SEHR spectra of CV contain the bands, caused by vibrations with and irreducible representations, that strongly confirm our idea about the main reason of surface enhanced optical processes and SEHRS in particular-the strong dipole and quadrupole light-molecule interactions.
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