Porcine pancreatic α amylase

Quercus wutaishanica Bl. was harvested in Yanji, Jilin, China. Three batches of fresh acorn fruits were shelled and cut into small pieces of 0.5 cm in length before being pulverized, dried at 40 °C for 24 h, and passed through an 80-mesh sieve. The sieved powder was marked as acorn flour (AF). Isoamylase (1000 U/mL) from Pseudomonas adaceae was bought from Aoboxing Biotechnology Co., Ltd. (Beijing, China). Porcine pancreatic α-amylase (9 U/mg) and glucosidase from Saccharomyces cerevisiae (23.5 U/mg) were obtained from Yuanye Biotechnology Co., Ltd. (Shanghai, China). All other chemicals were purchased from Beijing Chemical Reagent Co. (Beijing, China).

Porcine pancreatic α‐amylase and glucoamylase (amyloglucosidase from aspergillus niger, CAS number 9032‐08‐0, enzyme activity 100,000 U/g) were purchased from Shanghai Yuanye Biotechnology. 3,5‐Dinitrosalicylic acid, sodium potassium tartrate, and sodium sulfite were purchased from the Damao Chemical Reagent Factory. Crystalline phenol, sodium hydroxide, and anhydrous sodium acetate were purchased from Tianjin Fuchen Chemical Reagent Factory. Glacial acetic acid was purchased from Tianjin Kermel Chemical Reagent, and glucose was purchased from Guangzhou Chemical Reagent Factory. The reagents used were all of analytical grade.
The constant temperature oscillator was purchased from Changzhou Aohua Instrument, the QUINTIX224‐1CN electronic balance was obtained from Sartorius Scientific Instruments, and the UV‐1800 UV–Visible Spectrophotometer was purchased from Shimadzu Corp.