Characterization and Antifungal Activity of Limonoid Constituents Isolated from Meliaceae Plants Melia dubia, Aphanamixis polystachya, and Swietenia macrophylla against Plant Pathogenic Fungi In Vitro

Table 2

The half-maximal inhibitory concentration (IC₅₀, µg/mL) of limonoids 2, 3, 6, 8, and 9 against the mycelial growth of phytopathogenic fungi and oomycetes in vitro.

Fungi	The half-maximal inhibitory concentration (IC50) (µg/mL)
	2	3	6	8	9
FO	>500	480.5 ± 20.9	>500	>500	nt
MG	386.3 ± 2.8	490.0 ± 21.1	>500	318.3 ± 1.2	422.8 ± 3.9
SR	94.0 ± 2.5	128.0 ± 3.6	79.4 ± 2.1	124.5 ± 4.9	nt
PS	>500	178.5 ± 4.2	434.3 ± 10.8	97.1 ± 3.4	nt
PC	>500	262.4 ± 10.6	>500	280 ± 11.4	nt
PP	nt	351.5 ± 9.6	>500	>500	nt

^aFO : Fusarium oxysporum; MG : Magnaporthe oryzae; SR : Sclerotium rolfsii BV; PS : Phytophthora spp.; PC : Phytophthora capsici; PP : Phytophthora palmivora. ^bCompounds: 2, (3α,8R,9S,20R,24S)-20,24-epoxytirucalla-3,25-diol; 3, chisocheton compound G; 6, seneganolide; 8, khayanolide B. nt: not tested.