Modares Journal of Biotechnology

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 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 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 Abstract:

Aptamers are single-stranded sequences of RNA, DNA, or highly specific proteins that tend to bind to a wide range of target molecules. Aptamers are widely used in various fields, especially medicine and diagnostics, and are similar in their application to antibodies. There are many benefits to using aptamer instead of antibodies, such as low cost, longer life, increased tissue permeability, and more. There are several methods for producing aptamer that in silico methods can shorten and simplify the steps of aptamer production. With aptamer modeling, a set of in silico methods such as modeling, docking, and molecular dynamics can be used to screen for the best aptamer sequence. In this article, a review of the types of aptamers, their structure and design methods in silico is briefly stated.

Keywords: Aptamer, DNA, RNA, Protein, insilico



Keywords: Aptamer, DNA, RNA, Protein, insilico