4.2.

Antivirulence

Natural product	Compound Class	Plant source	Antibacterial activity			Mechanism	Other biological activity	References
			Bacterial target	Activity	Derivative activity
Curcumin (21) (22) (23)	Diarylheptanoids		Streptococcus pneumoniae Nan A; V. cholerae	0.6–5.3 µM (IC50)	0.2–1.9 µM (IC50)	Sialidase inhibitors	–	161
Ligustchuanes (3) (4)	Lignans	Ligusticum striatum DC.	Staphylococcus aureus	(4) 3 – 6 µM* (3)96 µM*	–	Inhibits α-hemolysin secretion	–	162
Paeonol (28)	Methoxybenzenes	Paeonia spp., dried root bark	Salmonella enterica serovar Typhimirium	95–190 µM*	–	T3SS inhibitor, reduces SipA translocation and expression of effector proteins	–	163
Salvianolic acid A (24)	Phenolic derivatives	Salvia miltiorrhiza Bunge	Staphylococcus aureus	5.75 µg/mL (IC50)	–	Inhibition of SrtA activity	–	164
Resveratrol oligomers (25) (26) (27)	Stilbenes	Vitis vinifera L.	Pseudamonas syringae pv. Tomato DC3000	25–100 µM*	–	Inhibition of T3SS through downregulation of hrp gene expression	–	165
Corilagin (19)	Tannins	Terminalia chebula Retz	S. aureus	6–10 µg/mL*	–	Quorum sensing inhibitor through agrA, Anti-α-hemolysin	Biofilm inhibition, Pigment inhibition. Decreased STX production	166
Betulin (40)	Terpenoids	Betula spp.	Listeria monocytogenes	4.5 – 36 µM*	–	Inhibition of exotoxin, LLO activity	–	147
Celastrol (41)	Terpenoids	Tripterygium spp.	S. aureus	0.44–2.2 µM*	–	Decreased expression of virulence transcriptional regulators SigB, msaB, and stress adaptor yjbH	–	167
Triterpenoid acids (42) (43) (44)	Terpenoids	Schinus terebinthifolia Raddi	S. aureus	2–70 µM (IC50)	–	Quorum sensing inhibitors	Biofilm inhibition	168

^*Unspecified IC₅₀, IC₉₀, or activities of multiple assays listed as range