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PubMed · 7763343

Development of a cyclodextrin production process using specific adsorbents.

M Okabe·Y Tsuchiyama·R Okamoto
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Abstract

Novel adsorbents that are composed of ligand, spacer, and support were chemically synthesized, and the two consecutive screenings made it possible to determine the adsorbents that were most suitable for alpha- and beta-CD production, respectively. Stearic acid was the most effective ligand for alpha-CD, whereas cyclohexanepropanamide-n-caproic acid was best for beta-CD. The adsorption selectivity of adsorbents derived from carboxylic acids (stearic or palmitic acid) and Chitosan beads was almost 100%, and their adsorption capacities were large enough to meet the demand for economical production and purification of CDs on an industrial scale. Next we discussed a novel process of alpha-CD production using the newly synthesized adsorbent characterized by the exceedingly powerful selectivity of alpha-CD from other CDs. alpha-CD production was carried out in the closed system converted to CDs by CGTase, and the column was packed with the adsorbent selective for alpha-CD. The yield of alpha-CD was 22.3%, and alpha-CD occupied a fraction of 57.4% in the overall CD reaction mixture. In the batch system without adsorbent, the yields of alpha-CD and its fraction were 10.8 and 24%, respectively. This novel process is particularly useful for the large-scale production of alpha-CD, in which the use of organic solvent is not preferable. We will now develop a novel process for the industrial production of CDs other than alpha-CD, such as gamma-CD, by using specific adsorbents.

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M Okabe, Y Tsuchiyama, R Okamoto. 1993. Development of a cyclodextrin production process using specific adsorbents.. https://pubmed.ncbi.nlm.nih.gov/7763343/

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