Study on antifungal constituents of Pogonatherum crinitum

In order to explore the application prospects of Pogonatherum crinitum in the control of agricultural plant disease, the antifungal activities of the extracts of P. crinitum were tested against 20 agricultural pathogenic fungi. The results showed that these extracts had moderate activities and the inhibition rate of ethyl acetate extract (2.00×10³ mg/L) were 50% against 8 pathogenic fungi. Especially that against P. capsici was 100%. The structure of 10 compounds were identified by ESI-MS, ¹³C NMR, ¹H NMR as 1, 2, 4-trihydroxybenzene ( 1 ), 1, 2-tidroxy-4-methoxybenzene ( 2 ), tricin-7-O-β-D-glucopyran-oside ( 3 ), tricin ( 4 ), β-adenosine ( 5 ), caffeic acid ( 6 ), spicatolignan B ( 7 ), luteolin-6-C-β-boivinopyranoside-7-O-β-glucopyranoside ( 8 ), rutin ( 9 ) and quercetin ( 10 ). Compound 2, 3, 5, 7 and 10 were obtained from P. crinitum for the first time. The antifungal activities of these compounds had been tested by method of spore germination and the result showed that compound 6-10 have significant inhibiting effect on the tested plant pathogens. The EC₅₀ of compound 6 - 10 against Rhizoctonia solani and P. capsici were between 18.54-103.6 mg/L and 21.38-87.83 mg/L, respectively.