Microbial protein production from candida tropicalis ATCC13803 in a submerged batch fermentation process

Background and Objective: Microbial protein production can resolve one of the major world challenges, i.e. lack of protein sources. Candida tropicalis growth was investigated to specify a medium to reach the highest cell proliferation and protein production

Material and Methods: Fractional factorial design and the index of signal to noise ratio were applied for optimization of microbial protein production. Optimization process was conducted based on the experimental results of Taguchi approach designs. Fermentation was performed at 25[degree sign]C and the agitation speed of 300 rpm for 70 h. Ammonium sulfate, iron sulfate, glycine and glucose concentrations were considered as process variables. Optimization of the culture medium composition was conducted in order to obtain the highest cell biomass concentration and protein content. Experiment design was performed based on the Taguchi approach and L[-1]6 orthogonal arrays using Qualitek-4 software

Results and Conclusion: Maximum biomass of 8.72 log [CFU ml[-1]] was obtained using the optimized medium with 0.3, 0.15, 2 and 80 g l[-1] of ammonium sulfate, iron sulfate, glycine and glucose, respectively. Iron sulfate and ammonium sulfate with 41.76% [w w[-1]] and 35.27% [w w[-1]] contributions, respectively, were recognized as the main components for cell growth. Glucose and glycine with 17.12% and 5.86% [w w[-1]] contributions, respectively, also affected cell production. The highest interaction severity index of +54.16% was observed between glycine and glucose while the least one of +0.43% was recorded for ammonium sulfate and glycine. A deviation of 7% between the highest predicted cell numbers and the experimented count confirms the suitability of the applied statistical method. High protein content of 52.16% [w w[-1]] as well as low fat and nucleic acids content suggest that Candida tropicalis is a suitable case for commercial processes

Constructing a mouse Oct4 promoter/EGFP vector, as a whole-cellular reporter to monitor the pluripotent state of cells

The transcription factor Oct-4, is an important marker of undifferentiating level and a key regulating factor for maintenance of pluripotency in cells. Establishment of an Oct-4 promoter-based reporter ystem is an appropriate tool for monitoring the differentiation of embryonic stem cells both in vivo and in vitro. In the present study, we report construction of a recombinant vector, pDB2 Oct4 promoter/EGFP, in which expression of Enhanced Green Fluorescent Protein [EGFP] was controlled by the mouse Oct-4 promoter. In transfected mouse embryonic stem cells with this vector, EGFP was predicted to be specifically expressed in pluripotency state. After transfection, high-level expression of EGFP under the control of Oct-4 promoter was observed in manipulated embryonic stem cells. Thus, our new cellular reporter showed that both the properties of embryonic cells and expression the EGFP could be of great help in studying the differentiating and reprogramming mechanisms of mESCs

[Production and physicochemical evaluation of Neisseria meningitidis serogroup A outer vesicle as a vaccine candidate]

Neisseria meningitidis serogroup A Polysaccharides vaccines have been available for many years, but these vaccines have many disadvantages due to their induction of T-Cell independent responses. To overcome these problems, many researches have been focused on other parts of bacterial cell component such as OMV [Outer membrane vesicle]. In this study, OMV containing PorA were extracted and evaluated by biological and immunological methods. OMV were extracted by siadat, et al method. Physicochemical properties of extracted OMV were analyzed by electron microscopy and SDS-page. The toxicity of LPS content in OMV was assayed by LAL test. The Presence of PorA was confirmed by western blot. Antibodies synthesis after immunization by OMV was evaluated using ELISA method. The content of extracted protein was 0.1 mg/ml. Size of OMV was between 50 and 150 nanometer. SDS-PAGE showed that PorA was located in 35-40 kDa. LAL test showed that the endotoxin activity was ranged in 126EU/ml which is safe for using. The ELISA test showed that the total IgG titer was elevated after first injection. The results showed that the conformation of extracted OMV was stable, and there were no progeny determinants in OMV. Also, OMV elicited high level of specific antibodies against Neisseria meningitidis serogroup A. These results indicate that the OMV can be used as a meningococcal vaccine after further investigations

[Efficacy of continuing medical education on knowledge of general practitioners]

Continuing medical education [CME] is a necessary way to keep graduated physicians knowledge and practice up-to-date, thus, play an important role in improving health care. Several years after implementing these programs in the country of Iran, it is necessary evaluate the efficacy of these programs. The aim of this study was to evaluate knowledge of participants in CME program before and after of CME programs. All general practitioners [GPs] who were participated in CME programs of the Mazandaran University of Medical Sciences [Sari, Iran] in the spring of 2006 entered in the study. A self directed and multi choice questionnaire was designed to seek demographic characteristics and knowledge of them about titles by programs. Its reliability was evaluated by internal consistency and validity by attending. The questionnaires were distributed before and after of each program. Data was analyses by SPSS and paired T- test. From 300 participates, 235 persons were completed the questioner [q] [response rate=78%]. The mean points of ENT q before and after program was 9.15 +/- 1.95 and 9.75 +/- 1.61, respectively [total point 20]. In addition, these mean points were 9.85 +/- 2.29 and 10.22 +/- 1.79 [total 18] for general surgery, 11.79 +/- 2.65 and 14.12 +/- 3.38 [total 23] for psychiatry, 6.48 +/- 2.55 and 8.52 +/- 3.3 [total 19] for ophthalmology, 5.83 +/- 2.39 and 9.07 +/- 2.53 [total 17] for urology, and 7.79 +/- 2.11 and 10.68 +/- 2.54 [total 24]for dermatology. The mean scores of knowledge of GPs were low and CME programs could not improve it, therefore, it is necessary to re-evaluate the contents and methods of CME programs for improving knowledge of general practitioners