基礎生物分子工程專題實驗 生物分子工程學程

生物分子工程實驗專題 下學期學期初選定專題 學期中及暑 假時進行各組所選定之專題

1.Biological Fuel Cell 2. Bacterial Cellulose Production and Applications 3. Antibiotic Peptides Production and Applications 4.Cyclodextrin production by cyclomaltodextrin glucanotransferase 5.Immobilized Enzymes on eggshell as Biocatalyst for Biotransformations

專題要求 學期中每月各組專題進度報告一次 暑假結束前專題成果展示報告 邀其他同學老師觀摩成績由四位參與專 題學程老師評定 專題需改進加強部分繼續在九十四學年 下學期中完成

What is the fuel cell? A fuel cell is a device for the direct energy conversion of chemical energy to electrical energy. It includes an anode, a cathode, a supporting electrolyte medium to connect the two electrodes, an external circuit to utilize the energy. Reactants must be supplied to both electrodes as a source for the electron transfer reactions. Catalysts must be present to provide a rapid rate of reaction at each electrode. Direction of electron and ion flow in fuel cell: External circuit open, no electrons or ions flow External circuit closed, electrons move from the anode to the cathode and positively charged ions move from the anodic compartment to the cathodic compartment Reduction of oxidizing fuel Ion-Exchange Membrane External Circuit Oxidation of reducing fuel AnodeCathode Electrolyte electrons Electric Consumer H+H+ H+H+ H+H+ H+H+ H+H+

Biofuel Cell

Distinction between Conventional Fuel Cell and Biofuel Cell Conventional Fuel Cells use precious metal as catalyst. Biofuel Cells utilize enzymatic catalysts, either as they occur in microorganisms, or as isolated proteins. There are two types of biofuel cells: direct and indirect  The direct biofuel cell is a configuration in which fuel is oxidized at the surface of the electrode.(Enzyme have been used as catalysts in direct biofuel cells)  The indirect biofuel cell is a configuration in which fuel reacts not at the electrode, but in solution or in a separate compartment, and a redox active mediator is added to shuttle electrons between the site of reaction and the electrode. ( microorganisms have often been used in indirect biofuel cell)

Biocellulose Cellulose is the main component of plant cell wall. Some bacteria produce cellulose (celled biocellulose or bacterial cellulose). Plant cellulose and bacterial cellulose have the same chemical structure, but different physical and chemical properties. Figure 1 shows an electron microscopic image of biocellulose and plant cellulose. Bacterial cellulose is produced by an acetic acid-producing bacterium, Acetobacter xylinum. The diameter of biocellulose is about 1/100 of that of plant cellulose and Young's modulus of biocellulose is almost equivalent to that of aluminum. Therefore, biocellulose is expected to be a new biodegradable biopolymer. Bacterial Cellulose

Bacterial cellulose and plant cellulose.

The predicted pathway of cellulose synthesis and secretion when glucose is taken into Gluconacetobactor xylinum from the outside of the cell

Bacterial Cellulose

Antibiotic Peptides Primary structure of Nisin Agar well diffusion method The mode of action of the Lipid II mediated pore-formation by nisin

Chitosan is the deacetylated product formed bytreatment of chitin with concentrated(50%) caustic alkali. Chitin, a polysaccharide of animal origin,is obtained from waste material of seafood industries. It occurs in the skeletal materialof crustaceans such as crabs, lobsters,shrimps, prawns and crayfish.

Antimicrobial activity of Chitosan (central disc) and other standard antibiotics against resistant strains of S. enterica var. Paratyphi-A-1, S. enterica var. Paratyphi-B-3, and S. enterica var. Paratyphi-B-4.

Cyclodextrins are cyclic oligo-glucopyranose molecules linked via "(1÷4) glycosidic bonds consisting mainly of 6, 7 or 8 glucose residues, , ,  - cyclodextrin. The increasing use in industrial and research applications of cyclodextrins is based upon their ability to form inclusion complexes with many small hydrophobic molecules. Cyclodextrin production

Cyclodextrin (CD) is synthesized by bacterial cyclodextrin glycosyltransferase (CGTase) and is widely used in food, pharmaceutical, cosmetic, and agricultural industries.

Eggshell membrane, having excellent gas and water permeability,may be an ideal biomaterial for enzyme immobilization.Its thickness is approximately  m and it is mainlycomposed of biological molecules and protein fibers, which may supply polycations to stabilize the enzymes. With the protection of eggshell and eggshell membrane, if not infected by microbes and bacteria, an egg can be kept fresh for a long time. Eggshell membrane

Scanning electron micrographs of the eggshell membrane. (a) Fresh eggshell membrane. (b) Eggshell membrane immobilized with enzyme. (a) (b)