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Beta Glucan Production from Two Strains of Agrobacterium sp in Medium Containing of Molases and Uracil Combine  [PDF]
Biodiversitas , 2007,
Abstract: Production of β-glucan by Agrobacterium sp is influenced by the composition of nutrition in the fermentation media. Molases has been used successfully by others in the fermentation media of S. cerevisiae to increase the yield of -glucan, and similarly, uracil has been used in the fermentation media of Agrobacterium sp to increase the yield of -glucan. Investigations to increase the yield of -glucan by two strains of Agrobacterium sp, i.e. A1.5 (reference) and B4.4 (local strain), have been carried out by addition of various combination of molases and uracil into fermentation media, i.e. 5%(v/v) molase-0,05%(b/v) uracil; 5% molase-0,025% uracil; 10% molase-0,05% uracil; and 10% molase-0,025% uracil. The β-1,3-glucan and β-1,2-glucan fractions were separated by extraction method. Beta-glucan concentration was determined as the glucose monomer using the phenol-sulphate spectrophotometric method at 490 nm. The protein content was determined by a modified Lowry-spectrophotometric method at 750 nm. The results showed that all combination of molases and uracil in the fermentation media of Agrobacterium sp A1.5 and B4.4 strains have increased both the dry-weight yield of β-glucan (crude) and the β glucan content, with the highest was in a medium containing 10% molases-0,025% uracil combination. In the above medium, the A1.5 strain produced the highest β-glucan (7,5%) with the lowest protein content ( 8,4%) in the β-1,3-glucan fraction, while the β-glucan content in the β-1,2-glucan fraction were all lower than in the control media, while the protein content were all higher than in the control media. In the above media, the B4.4 strain produced the highest β-glucan, 7,2% in the β-1,3-glucan fraction, and 13,1% in β-1,2-glucan fraction, while the lowest protein content ( 8,4%) was in the β-1,3-glucan fraction. In conclusion, fermentation media of Agrobacterium sp A1.5 strain or B4.4 strain containing molase and uracil combination have increased both the dry-weight yield of total β-glucan (crude) and the β-glucan content, while reduced the protein content. There is no clear FTIR spectrum difference between supposedly β-1,2-glucan fraction and β 1,3-glucan fraction.
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.
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.
Production of Beta-1,3 Glucan from Agrobacterium and Its Wound Healing Activity on White Rat
Kusmiati,Amarila Malik,Sukma Nuswantara,Syafrida Siregar
Makara Seri Sains , 2006,
Abstract: The objective of this study was to determine the activity of beta-1,3 glucan product extracted from local Agrobacterium sp Bro 1.2.1, both wild-type and mutant-type, on opened-wound healing process. Beta-1,3 glucan product was extracted by precipitation, and the purification was carried out by column chromatography as KCl gradient fractions. In this study, white Sprague Dawley rats were employed, and have been treated for opened-wound condition. Seven groups were performed in this experiment, i.e. the negative control, the positive control employing povidone iodine, the two groups of two commercial beta-1,3 glucan with 0,02 mg/4 cm2 each, and the last three groups of beta-1,3 glucan as the test group with 0,02 mg/4 cm2, 0,10 mg/4 cm2 and 0,50 mg/4 cm2, respectively. The result showed significant differences of wound-healing activity performing statistical analysis of the least significance between the negative control, the positive control, as well as the highest dose of the test group of beta-1,3 glucan, at the dose of 0,5 mg/4 cm2 (p<0.05).
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,
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.
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