Isolation and identification of two phytotoxic compounds from the medicinal plant Cassia alata L.

Abstract

Cassia alata (Caesalpiniaceae), an ornamental shrub, has many biological properties such as antifungal and antibacterial activities. Several bioactive and phytotoxic compounds have already been isolated from C. alata. Phytotoxic substances from plants have drawn attention as an alternative biological approach to control weeds. Thus, we conducted this research to explore other phytotoxic compounds in C. alata leaves. Aqueous methanol extracts of C. alata leaves strongly inhibited the seedling growth of broccoli, cabbage, cress, radish and rapeseed, in which the level of inhibition correlated with concentration. Two active compounds were isolated through chromatographies and identified using spectral data as (S)‐4‐(3‐hydroxybutyl)phenol [(+)‐rhododendrol] and (E)‐4‐((1R,4R)‐4‐hydroxy‐2,6,6‐trimethylcyclohex‐2‐en‐1‐yl)but‐3‐en‐2‐one [3‐hydroxy‐α‐ionone]. These two active compounds inhibited the growth of cress seedlings in a concentration‐dependent manner. The required concentrations for 50% growth inhibition (I50 value) of cress seedlings were 192.0–296.1 μM for (+)‐rhododendrol and 132.4–195.3 μM for 3‐hydroxy‐α‐ionone. These results indicate that the two phytotoxic compounds play a part in the phytotoxic activity of C. alata leaves.

Allelopathy and Allelopathic Substances of Fossil Tree Species Metasequoia glyptostroboides

“…However, it was later found to cause leukoderma at a higher frequency, and its cosmetic products were withdrawn from the market [30,31]. The compound has recently isolated from the leaves of Cassia alata L. and has been reported to act as an allelopathic agent [32].…”

Assessment of Phytotoxins Using Different Technologies

“…Ligularia cymbulifera [63] Gas chromatography mass spectrometry (GC/MS) 2,4 di-tert-butylphenol, cis-9-octadecenoic methyl ester, and phthalic acid, mono-(2-ethylhexyl) ester Pennisetum purpureum [79] Glycosinolates Brassica napus [88] Auxins, abscisic acid, cytokinins, jasmonic acid, salicylic acid Medicago truncatula [89] GC/MSD Sesamin and ashantin Artemisia arborescens Cassia alata [93] Current Applied Science and Technology Vol. 22 No.…”