Imperata cylindrica, commonly known as blady grass, cogon grass, kunai grass, or Japanese bloodgrass, is a species of grass in the genus Imperata. It is placed in the subfamily Panicoideae, supertribe Andropogonodae, tribe Andropogoneae.
It is a perennial rhizomatous grass native to east and southeast Asia, India, Micronesia, Australia, and eastern and southern Africa. It grows from 0.6–3 m (2–10 feet) tall. The leaves are about 2 cm wide near the base of the plant and narrow to a sharp point at the top; the margins are finely toothed and are embedded with sharp silica crystals.
Bioactivity-guided fractionation of the methanolic extract of the rhizomes of Imperata cylindrica afforded a new compound, 5-hydroxy-2-(2-phenylethyl)chromone (1), together with three known compounds, 5-hydroxy-2-[2-(2-hydroxyphenyl)ethyl]chromone (2), flidersiachromone (3), and 5-hydroxy-2-styrylchromone (4).