TABLE 3.

The benefits and limitations of different metabolism models.

Models		Benefits	Limitations
Primary enteric models	Microbiome-based model	Directly or indirectly affects drug metabolism	It is difficult to operate and requires the participation of animals
	Cell-based enteric model	It mimicks well the environment of the intestine	It has difficult induce and culture process
Primary Hepatic Models	Hepatocytes	It is currently the “gold standard” for in vitro drugs and xenobiotics metabolism experiments	It is difficult to simulate in vivo processes perfectly
	Hepatocyte subcellular fractions	It is convenient and easy to prepare, has good reproducibility, easy storage of enzyme mixture and easy optimization of incubation conditions	It lacks a complete metabolic enzyme system
Others	PCTS	It retains the activity of metabolic enzymes relatively intact, allowing the simultaneous analysis of multiple metabolites	It has high requirements on the operation of the experimenter
	Isolated tissue perfusion system	It maintains the integrity of organs and cells, allowing experiments to be performed under near-physiological conditions	It takes a long time, and the segment tends to lose activity
	Gene recombinant enzymes	It is suitable for studying microscopic and detailed problems in the field of metabolism	The experiment cost is high, and the conditions are quite different from the internal environment
	Animals	It reflects the influence of phase I and phase II metabolic enzymes in living individuals	The experimental process is expensive, time-consuming, difficult to operate, has individual differences and ethical concerns