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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Iranian Journal of Biotechnology
- نوع مقاله: Journal Article
- کلمات کلیدی: Cytotoxicity,Liposomes,Eptifibatide,Materials Testing
- چکیده:
- چکیده انگلیسی: Background: Eptifibatide (Integrilin®) is a hepta-peptide drug which specifically prevents the aggregation of activated platelets. The peptide drugs are encapsulated into nanolipisomes in order to decreasing their side effects and improving their half-life and bioavailability.
Objectives: In this study, the in vitro cytotoxicity and hemocompatibility of RGD-modified nano-liposomes (RGD-MNL) encapsulated a highly potent antiplatelet drug (eptifibatide) was investigated.
Material and Methods: RGD-MNL encapsulated eptifibatide was prepared using lipid film hydration and freeze/thawing method. The morphology and size distribution (about 90 nm) of RGD-MNL were characterized using transmission electron microscopy (TEM). The in-vitro cytotoxicity of nano-liposomes was examined using the MTT, LDH release and reactive oxygen species (ROS) generation assays. The effect of RGD-MNL on red blood cells (RBC) was investigated using hemolysis and LDH release assays.
Results: The results revealed that RGD-MNL had no significant cytotoxic effect on HeLa and HUVEC cell lines, and also no ROS generation increase in the cells. In addition, the adverse effect of RGD-MNL on LDH release and membrane integrity of RBC was not observed.
Conclusions: In conclusion, the recommended RGD-MNL formulations have not any significant cytotoxicity on normal cells or RBC and have potential for protecting and enhancing the activity of antiplatelet drugs.- انتشار مقاله: 29-07-1396
- نویسندگان: Hassan Bardania,Seyed Abbas Shojaosadati,Farzad Kobarfard,Dina Morshedi,Farhang Aliakbari,Mohammad Taher Tahoori,Elahe Roshani
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Biotechnology
- نوع مقاله: Journal Article
- کلمات کلیدی: Pichia pastoris,Elemental Analysis,Alpha 1-antitrypsin,Designing Medium,Medium Optimization
- چکیده:
- چکیده انگلیسی: Background: Human alpha 1-antitrypsin (AAT) is a monomeric glycosylated protein; it is the potent inhibitor of a whole range of serine proteases and protects tissues against their destructive effects. The human plasma-derived AAT, which is currently used to augment the AAT level in patients, is limited due to high cost and source limitation. Recombinant production of AAT can be considered as a potential alternative.
Objectives: This study aims to develop and optimize a new chemically defined medium based on an elemental analysis of the yeast Pichia pastoris for an efficient culture of the recombinant yeast-producing secretory AAT.
Material and Methods:An elemental analysis of Carbon (C), Hydrogen (H), Nitrogen (N), Sulfur (S); CHNS in its abbreviated form, and metallic elements was performed to determine the exact molecular constituent of the P. pastoris. The medium components were selected according to the obtained formula; they were optimized by the response surface methodology (RSM). The grown yeast cell was measured at the end of 18 h glycerol batch culture. The amounts of AAT production and elastase inhibitory capacity (EIC) were measured at the end of three days’ methanol feeding.
Results: The optimized medium compositions consist of glycerol (40 g.L-1), KH2PO4 (24.78 g.L-1), NaCl, (0.88 g.L-1), MgSO4.7H2O (1.95 g.L-1), (NH4)2SO4 (22.76 g.L-1), and trace elements (20 mL.L-1). The presented quadratic models show that KH2PO4 and (NH4)2SO4, are the most abundant ones in the P. pastoris biomass and have the greatest effect on the cell growth, EIC, and AAT protein production responses.
Conclusions: According to the results of this study, it can be concluded that the characterizing cell composition formula could be considered as an appropriate method to design culture media in order to improve cell growth and productivity. Compared to the common P. pastoris chemically defined media, FM22 and BSM, production of AAT protein increased by 1.5 and 1.4 times, respectively, in this new medium.
- انتشار مقاله: 26-01-1395
- نویسندگان: Tina Tavasoli,Sareh Arjmand,Seyed Omid Ranaei Siadat,Seyed Abbas Shojaosadati,Abbas Sahebghadam Lotfi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Biotechnology
- نوع مقاله: Journal Article
- کلمات کلیدی: Eptifibatide,RGD-modified nano-liposomes (RMNL),RMNL encapsulated eptifibatide
- چکیده:
- چکیده انگلیسی: Background: Eptifibatide (Integrilin) is an intravenous (IV) peptide drug that selectively inhibits ligand binding to the platelet GP IIb/IIIa receptor. It is an efficient peptide drug, however has a short half-life. Therefore, antithrombotic agents like eptifibatide are required to become improved with a protected and targeted delivery system such as using nano-liposomes to the site of thrombus. Objectives: The goal in the present report was to optimize encapsulation efficiency of the eptifibatide into Arg-Gly-Asp (RGD)-modified nano-liposomes (RMNL). As well, it was intended to evaluate the effect of sodium lauryl sulfate (SLS) on drug release. Materials and Methods: The effect of five independent variables including number of freeze/thawing cycles, concentration of eptifibatide, 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), cholesterol, and dipalmitoyl-GRGDSPA peptide on drug entrapment efficiency (DEE) was investigated using response surface methodology (RSM). The effect of different concentrations of SLS on encapsulation and drug release from RMNL was also investigated. The size and morphology of RMNL were characterized using transmission electron microscopy (TEM). Results: The maximum DEE (38%) was obtained with 7 freeze/thawing cycles, 3.65 mmoL eptifibatide, 7 mM DSPC, 3 mM cholesterol, and 1 mM dipalmitoyl- GRGDSPA peptide. SLS has significantly increased the drug release from RMNL, although its effect on encapsulation efficiency was not significant. Conclusions: The optimization of the formulations for valuable and expensive peptide drugs is essential to have the maximum encapsulation efficiency and the minimum experiments.
- انتشار مقاله: 26-08-1394
- نویسندگان: Hassan Bardania,Seyed Abbas Shojaosadati,Farzad Kobarfard,Farid Dorkoosh
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Biotechnology
- نوع مقاله: Journal Article
- کلمات کلیدی: Physicochemical properties,Desolvating agents,Human serum albumin nanoparticles
- چکیده:
- چکیده انگلیسی: Background: Recently, applications of albumin nanoparticles as drug delivery carriers have increased. Most toxicology studies have shown that surface chemistry and size of nanoparticles play an important role in biocompatibility and toxicity. Objective: The effect of desolvating agents with different chemical properties on the size of synthesized HSA NPs was investigated. Materials and Methods: Acetone, ethanol, methanol, and acetonitrile were used to synthesize HSA NPs with controllable size by desolvation method. Scanning electron microscopy (SEM), dynamic light scattering (DLS), and circular dichroism (CD) were employed to characterize produced particles. Finally, the toxicity of HSA NPs synthesized under different conditions was evaluated on PC-12 cells. Results: The sizes of synthesized particles differed according to the different solvents used. The sizes were 275.3 nm, 155.3 nm, 100.11 nm, and 66.2 nm for acetonitrile, ethanol, acetone, and methanol, respectively. CD showed that larger NPs had more changes in the secondary structures. Finally, the toxicity monitored on the cultured PC-12 cells showed no significant toxic effect through treating with these NPs at different concentrations (0-500 mg.mL-1). Conclusions: The size of HSA NPs has a strong dependency on the desolvating agent. The mechanism in which the desolvating agent affects the size of HSA NPs is complex. Various factors such as dielectric constant, polarity, functional groups, and hydrogen bonding of the solvents have the potential to affect the size and structure of HSA NPs. CD analysis suggested that the solvent denaturing capability had a critical effect on the HSA particle size. The stronger denaturing capability of the solvent resulted in the larger HSA particle size.
- انتشار مقاله: 02-12-1393
- نویسندگان: Hossein Mohammad-Beigi,Seyed Abbas Shojaosadati,Dina Morshedi,Negar Mirzazadeh,Ayyoob Arpanaei
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Biotechnology
- نوع مقاله: Journal Article
- کلمات کلیدی: human papillomavirus,Cell penetrating peptide,E7,Gene delivery,MPG-based nanoparticles
- چکیده:
- چکیده انگلیسی: Background: The poor permeability of the plasma and nuclear membranes to DNA plasmids are two major barriers for the development of these therapeutic molecules. Therefore, success in gene therapy approaches depends on the development of efficient and safe non-viral delivery systems. Objectives: The aim of this study was to investigate the in vitro delivery of plasmid DNA encoding HPV16 E7 gene using cell penetrating peptide delivery system to achieve the best conditions for cell transfection and protein expression. For this purpose, we have used a cationic peptide delivery system, MPG which forms stable non-covalent complexes with nucleic acids for delivery of pEGFP-E7 as a model antigen in vitro. Materials and Methods: DNA construct encoding HPV16 E7 (pEGFP-E7) was prepared in large scale with high purity. MPG peptide/ DNA complexes were prepared at different N/P (nitrogen/phosphate) ratios and physicochemical characterization and stability of nanoparticles were investigated. In vitro peptide-mediated E7-GFP DNA transfection, and its expression was evaluated in three cell types. To quantify the transfection efficiency of this delivery system, transfected cells were harvested and assessed for GFP-positive cells by flow cytometry. Furthermore, E7-GFP expression was confirmed by western blot analysis. Results: The cellular uptake of MPG based nanoparticles was shown to be comparable with standard reagent PEI. The COS-7 cells transfected by MPG-based nanoparticles at an N/P ratio of 15:1 showed the highest transfection efficiency and gene expression. Conclusions: The results indicated that the efficient gene expression depends on both cell type and N/P ratio applied, in vitro. The efficient protein expression detected by western blotting and flow cytometry supports the potential of MPG-based nanoparticles as a potent gene delivery system.
- انتشار مقاله: 06-10-1393
- نویسندگان: Tayebeh Saleh,Azam Bolhassani,Seyed Abbas Shojaosadati,Saman Hosseinkhani
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Biotechnology
- نوع مقاله: Journal Article
- کلمات کلیدی: Mathematical Modeling,Solid-state fermentation,Growth Kinetics,Product Formation Model
- چکیده:
- چکیده انگلیسی: Context:In this review, we discuss empirical and stoichiometric models, which have been developed recently in SSF processes and the influence of environmental conditions on the variables of these models. Additionally, new studies on modeling of product formation are also mentioned. Evidence Acquisition:Solid-state fermentation (SSF) is recognized as a cheap process for producing many valuable products like industrial enzymes and bioethanol. To develop, optimize, and scale-up this process, mathematical models are required. In this review, we collected all the papers regarding microbial growth and product formation modeling in SSF. The pros and cons of each model and confirmation with experimental data were also discussed. We discussed here the simple empirical growth kinetics models and the effect of environmental conditions on these models parameters, stoichiometric models and product formation models. Results:Simple empirical models are used widely in the kinetic modeling of SSF processes due to their simplicity and ease of use. However, more studies should be done in this field to make them more accurate, especially; the effect of environmental conditions, like temperature and moisture, on key variables of the model must be considered. Robust modeling methods, like stoichiometric models, are in their early stages in SSF processes and require more studies. Developing models in which transport phenomena models are coupled with the growth kinetics models can help better SSF bioreactor designing. On the other hand, to use SSF for producing valuable products, product formation models, which are not developed well in SSF processes, are necessary. Conclusions:To use SSF for producing valuable metabolites in large scales, more attention is required for modeling the SSF processes, especially for product formation models and using modern methods like stoichiometric models.
- انتشار مقاله: 12-09-1391
- نویسندگان: Davood Mazaheri,Seyed Abbas Shojaosadati
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Biotechnology
- نوع مقاله: Journal Article
- کلمات کلیدی: silver nanoparticles,Green synthesis,Tollens method,Microbial synthesis,Polysaccharide method
- چکیده:
- چکیده انگلیسی: In the present study, properties of silver nanoparticles (AgNPs) such as average size, size distribution and
morphology were investigated by Tollens, polysaccharide, modified polysaccharide and microbial methods.
The synthesized AgNPs were characterized by UV-visible spectroscopy, scanning electron microscopy
(SEM), transmission electron microscopy (TEM), dynamics light scattering (DLS) and energy dispersive
X-ray (EDX) analyses. Analysis of reaction mixtures confirmed that Tollens, polysaccharide and modified
polysaccharide methods generated smaller AgNPs with better size distribution as compared to that produced
in microbial method. The average size of produced AgNPs by Tollens, polysaccharide and modified
polysaccharide were 42, 30 and 20 nm respectively. Moreover, microbial method generated AgNPs with average size of 54 nm in the case of cell-free filtrate mediated synthesis and 84 nm in case of the supernatant mediated synthesis. Analysis of fungus-mediated synthesis of AgNPs showed that the size distribution of AgNPs produced by supernatant is narrower than that produced by filtrate. Also, cell-free filtrate
resulted in the formation of smaller AgNPs with average size of 59 nm compared to the supernatant. The
comparative analysis of produced AgNPs by the above mentioned methods confirmed that modified polysaccharide method led to the formation of AgNPs with smallest size and highest productivity.- انتشار مقاله: 11-04-1391
- نویسندگان: Sepideh Hamedi,Seyedeh Masumeh Ghaseminezhad,Seyed Abbas Shojaosadati,Soheila Shokrollahzadeh
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Biotechnology
- نوع مقاله: Journal Article
- کلمات کلیدی: Solid state fermentation,Submerged fermentation,Ca-independent α-amylase,Bacillus sp. KR-8104
- چکیده:
- چکیده انگلیسی: This study investigates the production of crude Ca-independent and low pH active α-amylase by Bacillus
sp. KR-8104 in submerged fermentation (SmF) and solid-state fermentation (SSF) systems. Different
parameters were evaluated in each system using “one factor at a time” approach to improve the production of
enzyme. The results showed that in the SmF the maximum enzyme production was achieved in culture
medium that contained dextrin as a carbon source, as well as yeast extract and meat extract as nitrogen
sources incubated at 37ºC and 180 rpm for 48 h. While SSF of Bacillus sp. KR-8104 using wheat bran (WB)
as a substrate showed that using tap water or distilled water as a moisturizing agent, a substrate-water ratio
of 1:1.5 (w/v) and incubation at 37ºC for 48 h gave the maximum α-amylase production. From different
extraction medium examined in this study 0.1% (v/v) aqueous mixture of Tween 20 and distilled water illustrated maximum results (~100 U/g).
- انتشار مقاله: 10-04-1390
- نویسندگان: Maryam Hashemi,Seyed Abbas Shojaosadati,Seyed Hadi Razavi,Seyyed Mohammad Mousavi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Biotechnology
- نوع مقاله: Journal Article
- کلمات کلیدی: E. coli,Overexpression,Human IL-2,Soluble protein,Inclusion body
- چکیده:
- چکیده انگلیسی: Selection of a system for successful recombinant protein production is important. The aim of this study was
to produce high levels of human interleukin-2 (hIL-2) in soluble form. To this end, the pET32a vector in
Escherichia coli BL21 (DE3) was used as an expression system, since it was previously used for the production
of mouse IL-2 in soluble form. The results indicated that contrary to expectations, the expressed protein
was in the form of inclusion bodies and perhaps amino acid differences between human and mouse IL-
2 should be determinant. The hIL-2 protein is a small peptide, therefore its recovery as a biologically functional protein by the process of refolding may be feasible and could lead to high yields at the industrial scale.
- انتشار مقاله: 09-07-1389
- نویسندگان: Sohrab Boozarpour,Majid Sadeghizadeh,Mohammad Ali Shokrgozar,Saman Hosseinkhani,Seyed Abbas Shojaosadati,Sara Gharavi,Ghasem Ahangari,Bijan Ranjbar
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Biotechnology
- نوع مقاله: Journal Article
- کلمات کلیدی: acetylcholinesterase,Biosensor,Bioreactor,Flow-through system,Silicate sol-gel,Multiwall Carbon Nanotube
- چکیده:
- چکیده انگلیسی: A flow-through biosensor consisting of a fixed bed bioreactor was employed to detect the insecticide
paraoxon. Based on the inhibition of organophosphorous insecticide to the enzymatic activity of acetylcholinesterase (AChE), using paraoxon as a model compound, the condition for detection of the insecticide were optimized. The influence of enzyme loading on the packing surface was studied and AChE loading was set at 0.36 U/cm2 for subsequent studies.
Maximum value of absorbance response occurred at the residence time in bioreactor of 5 min, that was chosen as the optimal residence time. This flow-through system gave a linear response (R2 = 0.9869) to
acetylthiocholine iodide (ATChI) at concentrations of 0.050 to 1 mM. Under appropriate conditions, the inhibition of paraoxon was proportional to its concentration in two ranges, from 0.25 to 25 mg/l and 25 to 60 mg/l and the detection limit for paraoxon was 7.3×10-8 M.
The incubation time was 14 min. These results demonstrate that silicate-multiwall carbon nanotube
(MWCNT) sol film is very efficient for retaining the activity of AChE with a good long-term stability.
- انتشار مقاله: 10-04-1389
- نویسندگان: Bahman Ebrahimi,Seyed Abbas Shojaosadati,Seyyed Mohammad Mousavi
- مشاهده