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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.
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.
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.
Biodegradation of Crystal Violet by Agrobacterium radiobacter

G K Parshetti,S G Parshetti,A A Telke,D C Kalyani,R A Doong,P Govindwar,

环境科学学报(英文版) , 2011,
Abstract:
Catheter associated bloodstream infection caused by R. radiobacter  [cached]
Sood S,Nerurkar V,Malvankar S
Indian Journal of Medical Microbiology , 2010,
Abstract: Rhizobium radiobacter is a gram negative bacillus that is infrequently recognized in clinical specimens but is emerging as an opportunistic human pathogen. Infections due to Rhizobium radiobacter are strongly related to the presence of foreign plastic material and effective treatment often requires removal of the device. We report a case of R. radiobacter bloodstream infection associated with a central venous catheter which was easily controlled by antimicrobial treatment and did not require removal of intravascular device. To the best of our knowledge, this is the first case report from India implicating R. radiobacter as a cause of human infection.
ISOLATION AND IDENTIFICATION OF AGROBACTERIUM SPP. FROM CHERRY CROWN GALLS AND THEIR SENSITIVITIES TO AGROCIN 84
樱桃根癌土壤杆菌及其对土壤杆菌素84敏感性的研究

Wang Huimin,Sui Xinhua,Li Jianqiang,
王慧敏
,隋新华,李健强,戴秀玉,马德钦,王建辉,刘继世

微生物学报 , 1998,
Abstract: Crown galls were sampled from cherry yards of Shandong, Hebei, and Liaoning Provinces. 46 pathogenic strains were isolated. Physiological and biochemical tests revealed that 4 stains were Agrobacterium tumefaciens(bio. l) and that the other 42 strains were A. rhizogenes (bio. 2), according tO the classifications and nomenclatUres of the genus Agrobacterium and the species revised by Sawada et al and Bouzar. The Ti plasheds of all strains were "opaline type. All strains were sensihve to agrocin 84, which suggested that crown gall disease of cheap could be controlled by K84 sabin.
Hairy Root Induced by Wild-type Agrobacterium rhizogenes K599 in Soybean, Cucumber and Garden Balsam in vivo
发根农杆菌K599对大豆、黄瓜和凤仙花活体感染生根的研究

XIANG Tai-He,WANG Li-Lin,PANG Ji-Liang,CHEN Min,XU Chao,
向太和
,王利琳,庞基良,陈 敏,许 超

遗传 , 2005,
Abstract: The plantlets of soybean, cucumber and garden balsam were inoculated by wild-type Agrobacterium rhizogenes K599, and hairy root was induced on inoculated sites in vivo. The frequencies of hairy root induction from wound cotyledons of soybean, cucumber and garden balsam were 100%, 65% and 91% respectively. Moreover, hairy root was induced from healthy cucumber axillary bud with frequency of 10%. PCR analysis of hairy root DNA was conducted using the primers from rolC gene. The PCR results showed that all hairy root lines contained T-DNA. The established system should be ideal for studying soybean and cucumber nematode and garden balsam breeding of flower dwarf architecture.
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