Citric Acid → (+)-Lactose

Participants

Reaction Steps

A solution of 0.2 mg of bovine pancreatic insulin (Wako Pure Chemical Industries, Itd.) in 1 mL of a 2 mmol/L aqueous solution of hydrochloric acid, a solution of 320 mg of anhydrous β-lactose (Nacalai Tesque, Inc.) in 2 mL of distilled water, and 1 mL of a 200 mmol/L phosphate buffer (pH 8.4) were mixed in a test tube. The mixture was subjected to reaction at 40° C. for 24 hours. To 3 mL of the resulting solution was added 0.5 mL of a 100 mmol/L aqueous solution of citric acid to adjust the pH to 5.9, and the mixture was subjected to reaction at 40° C. The reaction mixture was intermittently analyzed for products obtained by the reaction of insulin with lactose by HPLC in a manner similar to that in Example 1. The results are shown in Table 4.

Provenance & Evidence