ABSTRACT
Phenolic compounds have multiple bioactivities, such as anti-oxidant, anti-tumor, anti-bacterial, and anti-inflammatory activities. Recent literatures have demonstrated that flavonoids have a significant anti-anxiety effect on the central nervous system. In addition, studies showed that flavonoids acted as pro-drugs, which were transformed into smaller phenols through intestinal microflora. The small phenolic metabolites were crucial for the anxiolytic effects of these flavonoids, indicating that natural small-molecule phenols(NSMP) generally have anxiolytic activities. In this paper, the supporting evidences (before June 2016) from SciFinder database have been summarized. Furthermore, NSMPs were classified according to chemical structures; their anxiolytic effects, mechanisms, and the structure-activity relationships were also discussed.