Pharmacognostic profile of the leaf of Ageratum conyzoides

Abstract

Ageratum conyzoides Linn. (Asteraceae), commonly known as billy-goat weed and white weed, is an important plant in the Indian traditional medicine. It is widely used for the treatment of dysentery, diarrhoea, injuries, cuts, snake bites, pneumonia, and as an insecticide and nematicide. This work was an attempt to standardise and identify the leaf samples.: The fresh leaves of A. conyzoides were collected, from which macroscopic and quantitative microscopic studies were performed by using standard procedure to determine the diagnostic features for the identification and standardization. The leaves were found to have ovate, sub-acute and crenate with ciliate margins, the stem is greenish yellow covered with fine white hairs and flowers are white to mauve in colour, arranged in close terminal inflorescences. Light and electron microscopic data of the cross-section showed the presence of vascular bundles, parenchyma cells, collenchyma cells and multicellular non-glandular trichomes, upper and lower epidermal cells. Anomocytic stomata are seen in both upper and lower epidermis. Quantitative microscopic (such as Vein islet and vein termination, stomata number and stomatal index) were also determined after the leaves were boiled in chloral hydrate solution to remove the chlorophyll. Our results would be important in authentication of the leaf and analysing the pharmacopoeial standards of A. conyzoides.