Helsy Junaidi; Jeanne Adiwinata Pawitan
Abstract
The development of tissue engineering provides various opportunities to vascular tissue engineering. Scaffold plays an essential role in vascular tissue engineering. The selection of biomaterials used as scaffolds will determine the success of vascular tissue engineering. The structure of vascular system, ...
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The development of tissue engineering provides various opportunities to vascular tissue engineering. Scaffold plays an essential role in vascular tissue engineering. The selection of biomaterials used as scaffolds will determine the success of vascular tissue engineering. The structure of vascular system, which consists of three layers, is embedded in extracellular matrices that provide the mechanical properties of the system. Therefore, tissue engineering of a vascular structure needs various suitable biomaterials as scaffold that can support vascular system mechanical properties and function. Various materials were used for 3D printing and electro-spinning with good results, including collagen, gelatin, and alginate. Varying sizes of blood vessels require scaffolds with biomaterials that could adapt to their shape, size and approximate the mechanical properties of the blood vessels.
Abstract
Tryptophan (L-Trp) is a fundamental precursor to a number of drugs. In this research, three natural polymers included agar, agarose and alginate were investigated for immobilization of E. coli cells for L-Trp production to increase enzymatic stability. Also, the capability of beet molasses as serin (L-Ser) ...
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Tryptophan (L-Trp) is a fundamental precursor to a number of drugs. In this research, three natural polymers included agar, agarose and alginate were investigated for immobilization of E. coli cells for L-Trp production to increase enzymatic stability. Also, the capability of beet molasses as serin (L-Ser) substitution in production reaction was investigated. According to the results, optimum conditions for L-Trp production by immobilized biocatalyst were: agar with 2 % (w/v) as support matrix, 2 g of immobilized bacterial cells as biocatalyst. The immobilized biocatalyst showed acceptable operational stability, maintaining more than 80 % of the initial activity after 5 cycles and 0.604 g/l L-Trp was produced by 2 g of immobilized cells in comparison to 0.140 g/l by 3 g of free biocatalyst. Furthermore, results showed that beet molasses can be used as a cheap source of L-Ser in the L-Trp production reaction. As a consequence, combination of immobilization and cheap substrate was successfully developed.
