Table 3.

Advantages and disadvantages of different extraction methods

Methods	Advantages	Disadvantages
Hot water extraction	A. Simple operation. B. Low cost and suitable for large-scale industrial extraction.	A. Long time. B. Low extraction rate. C. High temperatures may cause degradation of polysaccharides.
Alkali solution extraction	A. Save time.	A. May disrupt polysaccharide structure. B. Increased cost of waste liquid treatment.
Microwave assisted extraction	A. Save time and high extraction efficiency.	A. Can not improve polysaccharide yield and purity.
	B. Maintain the structure and biological activity of polysaccharide.	B. Uneven heating.
Ultrasonic assisted extraction	A. Save time.	A. The extraction efficiency is not stable.
	B. Improve the homogeneity of raw material and solvent mixing degree.
Enzyme assisted extraction	A. Save time and high extraction efficiency.	A. Enzymes are easily inactivated.
	B. Low reaction temperature.	B. Enzymes are more expensive.