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Production, Purification, and Application of the Microbial Enzymes
Published in Pankaj Bhatt, Industrial Applications of Microbial Enzymes, 2023
Anupam Pandey, Ankita H. Tripathi, Priyanka H. Tripathi
In food science, for the purification of proteins, the widely used method is ion-exchange chromatography (IEC) which distinguishes the entities based on their charge. The stationary phase in IEC carries charged functional groups fixed by chemical bonds, which are associated with exchangeable counter ions. In the cation-exchange chromatography, the fixed groups are of positive charge, while the reverse is true for these groups in anion-exchange chromatography. This works on the principle that protein binds to exchanger at pH value either below or above their isoelectric point depending on the type of ion chromatography. The method involves the equilibration of resin with a low salt buffer followed by the sample application and its absorption, which is the complete desorption of bound protein. Desorption is carried out by increased salt concentration of elution buffer. The final steps involve the cleaning of a column to remove the strongly bounded substance. This method is widely employed because of its high binding capacity, which allows elution in concentrated form and separates protein with high resolution (Rossomando, 1990).
Feedstock Evaluation
Published in James G. Speight, Refinery Feedstocks, 2020
Cation-exchange chromatography has been used primarily to isolate the nitrogen constituents in a feedstock fraction. The relative importance of these compounds in feedstocks has arisen because of their deleterious effects in many refining processes. They reduce the activity of cracking and hydrocracking catalysts and contribute to gum formation, color, odor, and poor storage properties of the fuel. However, not all basic compounds isolated by cation-exchange chromatography are nitrogen compounds. Anion-exchange chromatography is used to isolate the acid components (such as carboxylic acids and phenols) from feedstock fractions.
Soluble expression, rapid purification, biological identification of chicken interferon-alpha using a thioredoxin fusion system in E. coli and its antiviral effects to H9N2 avian influenza virus
Published in Preparative Biochemistry and Biotechnology, 2019
Jun Zhao, Hai-Yang Yu, Yu Zhao, Feng-Hua Li, Wei Zhou, Bin-Bin Xia, Zhi-Yuan He, Jason Chen, Guo-Tuo Jiang, Ming-Li Wang
Anion-exchange chromatography is a process that separates substances based on their charges using an ion-exchange resin containing positively charged groups, such as diethyl-aminoethyl groups (DEAE). In solution, the resin is coated with positively charged counter-ions (cations). Anion exchange resins will bind to negatively charged molecules, displacing the counterion. Anion exchange chromatography is commonly used to purify proteins, amino acids, sugars/carbohydrates and other acidic substances with a negative charge at higher pH levels.