Enzymolysis-Microwave-Assisted Hydrodistillation for Extraction of Volatile Oil from Atractylodes Chinensis and Its Hypoglycemic Activity in vitro

Atractylodes chinensis (family Asteraceae) is a perennial herb with many pharmacological effects. Extraction of volatile oil from Atractylodes chinensis was optimized and its hypoglycemic activities were studied. Enzymolysis-microwave-assisted hydrodistillation (EMAHD) was adopted to extract the volatile oil, and the technology was optimized using a single-factor experiment that incorporated response surface methodology (RSM). The extraction rates of volatile oil by EMAHD, microwave-assisted hydrodistillation (MAHD), and hydrodistillation (HD) methods were compared at different times. The ingredients of Atractylodes chinensis volatile oil were analyzed by gas chromatography-mass spectrometry. Scanning electron microscopy (SEM) were used to analyze the microstructural changes in Atractylodes chinensis residue before and after extraction. The inhibition of α-amylase activity was determined. The obtained optimal extraction conditions for EMAHD were as follows: enzyme concentration 1.6%, pH 7, enzymolysis time 20 min, enzymolysis temperature 50°C, liquid-solid ratio 30:1, microwave power 455 W, and microwave time 40 min. The levels of the main ingredients and the in vitro inhibition of α-amylase activities were higher for Atractylodes chinensis volatile oil extracted by EMAHD than by HD or MAHD. The powder residue of Atractylodes chinensis remaining after EMAHD showed a ruptured and collapsed cell structure, indicating accelerated dissolution of the volatile oil. EMAHD is deemed a method with many advantages for extraction of volatile oil from Atractylodes chinensis. The volatile oil of Atractylodes chinensis is a promising component for treating hyperglycemia.