Table 1.

Various extraction techniques with different optimization conditions for natural products.

Method	Solvent	Temperature	Time	Volume of solvents used
Maceration	Water, aqueous, nonaqueous solvents	Room temperature	Long	Large
Soxhlet extraction	Organic solvents	Under heat	Long	Moderate
Supercritical fluid extraction	Supercritical fluid (usually S-CO2), sometimes with modifier	Near room temperature	Short	None or small
Ultrasound-assisted extraction	Water, aqueous, and nonaqueous solvents	Room temperature or under heat	Short	Moderate
Microwave-assisted extraction	Water, aqueous, and nonaqueous solvents	Room temperature	Short	None or moderate
Reflux extraction	Aqueous and nonaqueous solvents	Under heat	Moderate	Moderate