Modares Journal of Biotechnology

Abstract Aspergillus has many species that are important in medicine, agriculture, and various industries. The genus has 446 identified species, which are difficult to distinguish from each other with the use of morphological characteristics. Xylan 1,4-beta-xylosidase is an enzyme that catalyzes the hydrolysis process of xylose in xylooligosaccharides and is produced by different species of Aspergillus. This research was conducted with the aim of a bioinformatics study of the gene region related to this enzyme and to evaluate its similarities and differences in some Aspergillus species. The results showed that this gene region, due to the presence of conserved motifs, was able to distinguish some species studied in this research.

Abstract In this study, the wheat germ was fermented with industrial bakery yeast powder to produce FWGE with high 2,6-DMBQ content in a Bench-scale bioreactor by scale-up approach. The 2,6-DMBQ content of FWGE was increased by optimizing the three initial variables of pH, fermentation temperature, and agitation rate at two levels using the Taguchi method. The 2,6-DMBQ content of the samples was determined at 14, 16, and 18 hours of the fermentation process. Then, the results were analyzed by Qualitek software. The effect of centrifugation speed on turbidity and the yeast's number in the final supernatant was then investigated. Finally, the supernatant was dried by spray dryer with an inlet temperature of 120 °C and outlet temperature of 70°C, and the amount of active 2,6-DMBQ, pH, moisture, and ash was determined. Under optimal conditions: initial pH of 6, fermentation temperature of 32 °C, and agitation rate of 80 rpm, maximum 1.527 mg of 2,6-DMBQ per gram of FWGE obtained. The separation results showed that the centrifugation rate doesn't have a significant effect on the final turbidity and the number of yeasts left, and thus 3000 g was selected as the optimal speed. However, because of the high content of yeast in the supernatant, filtration was required after centrifugation. Due to the high speed of sample drying, the low moisture of the final product, and high efficiency on an industrial scale, the samples were dried using a spray dryer. Finally, the moisture, protein, ash, and pH of the final product were measured.

Abstract Fibrinogen is a major component of the coagulation cascade following tissue damage and rapidly forms an insoluble fibrin scaffold. Fibrin is a filamentous biopolymer that naturally forms from fibrinogen polymerization during blood clotting. After tissue damage and coagulation cascade initiation, soluble fibrinogen polymerization by thrombin enzymebegins and forms an insoluble fibrin network and blood clots with platelets. This fibrin network is crucial for the development of homeostasis after tissue damage. This biopolymer also plays a key role in the wound healing as a temporary scaffoldand due to its unique structural properties and physiological function; it is used in reconstructive medicine. Fibrin is able to absorb extracellular matrix proteins (ECM) such as fibronectin and growth factors. The main types of fibrin scaffolds like platelet-rich fibrin (PRF) and platelet-rich plasma (PRP) are being used as autologous biomaterials in reconstructive medicine, wound healing, orthopedics and skin reconstruction and cosmetic sciences. Fibrin derivatives and degradation products also play an important role in the process of wound healing by stimulating cell infiltration and tissue regeneration and they are being widely used in developing new products as a biological material for over a century.

Abstract Datura (Datura stramonium) is known as a rich source of tropane alkaloids, including scopolamine and hyoscyamine as parasympatholytics that competitively antagonize acetylcholine. Production of secondary metabolites often occurs in plants against the various elicitors or signal molecules. In this study, the effect of yeast extract as a biotic elicitor on tropane alkaloid production was evaluated. Surface-sterilized Datura seeds were cultured on 1/2 MS medium supplemented with different concentrations of yeast extract (0, 1.5, and 3g/L). One month after germination, alkaloid yield of Datura plantlets was measured by the use of High-Performance Liquid Chromatography (HPLC). Also, total protein content and antioxidative enzymes activity were determined by spectrophotometry method. According to the results, the fresh weight of root and shoot parts of Datura plantlets at 1.5g/L yeast extract was increased about 2 and 4 times, respectively. Yeast extract (1.5g/L) caused to 1.7 times increase of hyoscyamine amount of root and shoot parts and 2.5 folds scopolamine of Datura plantlets. Moreover, on yeast extract (1.5g/L)-treated plantlets, total protein content, and activity of catalase and guaiacol peroxidase were almost the same as the control group. Altogether, yeast extract (1.5g/L) can be used as a good candidate for enhancement production of tropane alkaloids especially hyoscyamine and scopolamine with high medicinal value.

Abstract Introduction: Macrophages are considered a particularly challenging cell type to transfect. Given their importance as therapeutic targets, developing a successful transfection method for these cells is highly desirable.
Materials and Methods: The efficiency of lentiviral transfection was compared to three commercially transfection reagents (Xfect™ Transfection Reagent, FuGENE® HD, and Lipofectamine ^TM 3000) in RAW264.7 macrophage cells. Following optimization and production of lentiviral particles in 293T cells, RAW264.7 cells were infected with varying MOI. Transduction efficiency, cell viability, and metabolic activity were measured and compared to the transfection efficiency of the chemical methods.
Results: None of the three chemical transfection reagents successfully transfected RAW264.7 cells. In contrast, the lentiviral method achieved transduction even at the lowest concentration of viral stock, with a green fluorescent signal observable under a fluorescence microscope. Increasing the viral stock concentration and using higher MOIs (up to 30) significantly (p≤0.0001) increased transduction efficiency.
Discussion: Despite requiring more time and effort than chemical methods, lentiviral transduction exhibited superior efficiency in transfecting hard-to-transfect cells and further improvements were achieved through some modifications such as virus concentration, the use of polybrene, no viral freezing and O/N incubation with concentrated viral particles. Since other parameters, especially the use of retronectin and spinoculation, are effective on the efficiency of the virus infection process, it is suggested that they be considered in future studies and given the encouraging data of this research, this completed method can also be applied to other difficult-to-transfect cells, such as different types of stem cells or primary cells.

Abstract Phenolic compoundes are present in nature and have gained extensive research attention because of their unique physiochemical properties and widespread industrial use. These phenolic compoundes are one of the most numerous and ubiquitous groups of plant metabolites and have many benefits for human health. However, low bioavailability of polyphenols is a big challenge in their therapeutic and nutritional effectiveness. Nanotechnology is an emerging field of science, and nanotechnological concepts have been studied for potential applications in the food and biomedical industry. Nanoparticles have specific characteristics and better functionality, thanks to their size and other physicochemical properties. Nanotechnology can overcome challenges of Phenolic compoundes and lead to improved bioavailability and targeted drug delivery and sustained release of them, while also reducing the required drug dose. Based on plant phenolic compoundes, this study reviews the chemical classification, metabolism and bioavailability of these compounds and also provides a brief description for nano-delivery systems of them to improve their potential in food and biomedical applications.

Abstract Aims: Saffron is one of the plants, whose allelopathic effect of various organs have been reported to affect seed germination of some weed species. The present research was conducted with the aim of evaluating the allelopathic effect of extraction solution of leaves and corms of saffron (Crocus sativus) in phenological stages on seed germination of jimson weed (Datura stramonium).
Materials and Methods: In this experimental study, an experiment was conducted to study the allelopathic effects of saffron on jimson weed seed germination at research farm, Tarbiat Modares University Faculty of Agriculture in autumn 2014. The experiment was arranged as factorial split plot in a completely randomized design with 3 replications. The treatments included factorial combination of 2 extract types (water and alcohol), 3 tissue compositions of saffron organs, different concentrations of aqueous, and alcoholic extracts as the main plots and 3 different phonological stages of saffron were considered as sub-plots. One-way analysis of variance was performed through generalized linear model (GLM), using SAS 9.1 software, and drawing charts was done, using Excel2013 software.
Findings: The concentration and phonological stage of saffron had a significant effect on the germination percentage of Datura stramonium, but the main effect of organ type on this trait was not significant. The aqueous extract of saffron did not have significant effect on the germination of Datura stramonium germination at the phonological stage of the daughter corms at a concentration of 2g/l in comparison with other phonological stages, but at a concentration of 4g, it significantly decreased the seed germination.
Conclusion: Extract of saffron has an allelopathic potential, and germination traits, including germination percentage and plumule and radicle length of Datura stramonium in different phonological stages of saffron are affected by the aqueous and alcoholic extracts of different organs.