The chitooligosaccharides from CBLS were prepared as described by Wu [11], but with slight modifications. Briefly, the original chitosan from CBLS was dissolved in 1% (v/v) aqueous acetic acid (HAc) to a concentration of 1% (w/v), and the pH was adjusted to 5.5 using 1 M NaOH. Forty milligrams of α-amylase was added into a reactor containing 500 mL of chitosan solution and then maintained in a thermostatic water bath at 55 °C for 4 h. Aliquots of the reaction mixture were periodically withdrawn, filtered, and heated to 95 °C for 15 min to terminate the reaction.