How dextran is produced?
Dextran is produced at the industrial level by the fermentation of sucrose-rich media. Several research workers have optimized fermentation conditions for maximum dextran production.
What is the composition of dextran?
Dextran is an exopolysaccharide produced by lactic acid bacteria, Leuconostoc mesenteroides. Structurally it is α-d-glucan, mainly composed of α-1,6-glycosidic linkage and small amount of α-1,2; α-1,3; and α-1,4 branched linkages.
What is a dextran polymer?
Dextran is a polymer of anhydroglucose. It is composed of approximately 95% alpha-D-(1-6) linkages. The remaining a(1-3) linkages account for the branching of dextran. 1,2,3. Conflicting data on the branch lengths implies that the average branch length is less than three glucose units.
Is dextran a natural polymer?
NATURAL POLYMERS: CELLULOSE, CHITIN, CHITOSAN, GELATIN, STARCH, CARRAGEENAN, XYLAN AND DEXTRAN.
Which of the following microorganisms produces dextran?
1. Which of the following microorganism produces dextran? Explanation: Leuconostoc mesenteroides is the producer organism for dextran which acts as a stabilizer in food products and as a blood plasma substitute.
What is the function of dextran?
Dextran is a medication used in managing and treating various clinical conditions, including during hemorrhage, shock, surgical procedures, radiological imaging, antithrombotic administration, and ophthalmic relief of xerophthalmia.
What classification is dextran?
Dextran is a polysaccharide that differs from others in that its glucose units are joined together 1:6 glucoside links.
What is the definition of dextran?
Definition of dextran : any of numerous glucose biopolymers of variable molecular weight that are produced especially by the fermentation of sucrose by bacteria (such as genus Leuconostoc), are found in dental plaque, and are used especially in blood plasma substitutes.
Which microorganism is used in industrial production of vitamin b12 Mcq?
Large scale industrial production of vitamin B12 occurs via microbial fermentation, predominantly utilizing Pseudomonas denitrificans, Propionibacterium shermanii, or Sinorhizobium meliloti [7].
What is the mechanism of action of dextran?
Mechanism of Action [7] Dextran reduces Von Willebrand factor to decrease the function of platelets. [8] It also activates plasminogen and prolongs bleeding time. These effects increase proportionally with the increase in the molecular weight of the dextran.
What is the difference between dextrin and dextran?
The polymer main chain consists of α-1,6 glycosidic linkages between glucose monomers, with branches from α-1,3 linkages. This characteristic branching distinguishes a dextran from a dextrin, which is a straight chain glucose polymer tethered by α-1,4 or α-1,6 linkages.
What is the classification of dextran?
How is vitamin B12 commercially made?
The commercial production of vitamin B12 is mainly achieved through the use of the two major industrial strains, Propionobacterium shermanii and Pseudomonas denitrificans, that involves about 30 enzymatic steps in the biosynthesis of cobalamin and completely replaces chemical synthesis.
What is the indication of dextran?
Why is Dextran Prescribed? (Indications) This medication is an anticoagulant, prescribed for hypovolaemic shock, thromboembolic disorders, pulmonary embolism, venous thrombosis and prophylaxis of post-op thromboembolic disorders.
What is trade name of dextran?
Gentran, LMD (dextran) dosing, indications, interactions, adverse effects, and more.
Which microorganism is used in the production of vitamin B12?
How is methylcobalamin manufactured?
Methylcobalamin can be produced in the laboratory by reducing cyanocobalamin with sodium borohydride in alkaline solution, followed by the addition of methyl iodide.
How is vitamin B12 manufactured?
Vitamin B12 is produced by bacteria, not animals or plants. As such, animals, including humans, must obtain it directly or indirectly from bacteria. It can be found in bacteria-laden manure and unsanitized water, though we obviously should not be consuming either of those things.
What are the commercial applications of dextran?
Commercial applications for dextran are generally in the pharmaceutical industry, but new applications are being considered in the food and textile industries (Nasab et al. 2010a;Sarwat et al. 2008). … Dextran is produced by Leuconostoc mesenteroides cultures (Nasab et al. 2010a) together with levan (Siddiqui et al. 2014).
Is dextran yield different in different media?
After certain fermentation period, the produced dextran was separated and dried. Dextran yield was calculated and significant differences in different media were observed. Furthermore, FT-IR analysis was performed and the results showed that there were no significant differences in the produced dextran structures.
What is the optimal pH for dextran production?
Molassesbased production medium resulted in the highest yield of dextran (55 g/L) in the optimal pH ranging from 6.75 to 7.5 [16, 17,36,37]. Thus, the optimal pH for dextran production is not a constant factor.
How do you make dextran from inoculums?
After preparation of inoculums, organisms were inoculated into five liquid fermentation media containing either molasses or cheese whey or different ombinations of cheese whey and molasses. After certain fermentation period, the produced dextran was separated and dried.