ObjectiveTo explore the impact of exogenous chitosan on the growth and metabolism of

Glycyrrhiza uralensis

Fisch. (

G

.

uralensis

) and to improve the quality of cultivated

G

.

uralensis

for both medicine and food and aid in the increase in the content of effective components in

G

.

uralensis

.MethodsIn this study

whole

G

.

uralensis

plants were treated with exogenous chitosan

and comprehensive analyses of secondary metabolites and proteins were conducted using liquid chromatography with tandem mass spectrometry and isobaric tag for relative and absolute quantitation

respectively. Effects of chitosan induction on endogenous hormones of

G

.

uralensis

were analyzed using an enzyme-linked immunosorbent assay. Gene ontology function annotation and Kyoto Encyclopedia of Genes and Genomes pathway annotation were conducted to study the effect of chitosan induction on the proteome.ResultsChitosan induction significantly increased the levels of flavonoids in

G

.

uralensis

; however

the variatio

n in triterpenoids was not substantial. Biological processes

including photosynthesis

secondary metabolism

and abiotic stress responses

were significantly enriched. Additionally

the photosynthetic pathway

photosynthesis-antenna protein pathway

and plant hormone signal transduction pathway were significantly enriched. In the flavonoid biosynthesis pathway

the upstream-related enzyme phenylalanine ammonia-lyase (PAL) and the downstream-related enzymes chalcone synthase (CHS)

polyketide reductase (PKR)

chalcone isomerase (CHI)

and vestitone reductase (VR) were significantly upregulated.ConclusionsOur findings suggest that chitosan induction may promote the tricarboxylic acid (TCA) cycle

and the TCA cycle enhancement significantly upregulated PAL

CHS

PKR

CHI

and VR

the five key enzymes involved in flavonoid synthesis of

G

.

uralensis

indicating that chitosan induction activated the entire metabolic pathway associated with flavonoids in

G

.

uralensis

. Our findings provide a reference for improving the quality of cultivated

G

.

uralensis

from the perspective of pharmacodynamic components.