Phytotoxic lignans of Leucophyllum frutescens

Abstract

Bioassay-guided fractionation of the hexane:ethyl acetate (1:1) extract of the leaves of Leucophyllum frutescens (Berl.) I.M.Johnst (Scrophulariaceae) led to the isolation of its phytotoxic constituents diayangambin (1), epiyangambin (2), diasesartemin (3) and epiashantin (4). Phytotoxicity was demonstrated as inhibition of seed germination of Agrostis stolonifera cv. penncross (Poaceae) and inhibition of development of Lactuca sativa L. (Asteraceae) seedlings in a microassay using 24-well plates. Compound 1 was the most phytotoxic to L. sativa, showing strong inhibitory activity at 110 microM. Compound 1 was more active than 2 and 3 in inhibiting the growth of A. stolonifera with I(50) values of 160, 670 and 930 microM, respectively. At a concentration of 500 microM, these compounds inhibited all phases of onion root cell division. This is the first demonstration of antimitotic activity of these furofuran lignans, and the first report of their isolation from this species.

Evaluation of the flora of Northern Mexico for in vitro antimicrobial and antituberculosis activity

“…Our findings suggest that this species has antituberculosis activity against sensitive and resistant strains of Mycobacterium tuberculosis. Some phytotoxic lignans have been isolated from this plant (Rimando et al, 1999) and calmodulin inhibitors have been reported in the closely related species Leucophyllum ambiguum (Rojas et al, 2003). However, there are no previous reports on the antituberculosis activity and chemical nature of the antituberculosis compounds in Leucophyllum frutescens.…”

Naturally occurring lignans efficiently induce apoptosis in colorectal tumor cells

“…Epiashantin, the most effective growth inhibitor in SW480 cells is found together with the related compounds yangambin and epiyangambin in medicinal plants with anti-mitotic activity (Rimando et al 1999) and was isolated from artemisia absinthum (wormwood), a spice used in liquors (Greger and Hofer 1980). The main activity of yangambin is inhibition of platelet activating factor (Castro-Faria-Neto et al 1995).…”

Effects of the Allelochemicals Dihydrodiconiferyl Alcohol and Lariciresinol on Metabolism of Lactuca sativa

“…Lignans are widely distributed in plants and derived from the phenylpropanoid pathway. These compounds exhibit interesting antimicrobic, antiviral, herbicidal, or antifeedant activities that are thought to participate in plant defence mechanisms against biotic stresses [11,12]. The cancer protective effects of dietary lignans have been also demonstrated [13] but not many data are available regarding the phytotoxic activity of this class of compounds or their ability to interact with other plant organisms.…”