A report on pharmacognostical evaluation of four Adiantum species, Pteridophyta, for their authentication and quality control

Genus Adiantum L., Pteridaceae, is an important fern used in traditional systems of medicine. Different species of Adiantum are known as avenca in Brazil; hansraj/hanmspadi in India; maiden hair fern in English. The present study aims to develop the quality control parameters of four similar looking Adiantum species viz. A. capillus-veneris L., A. lunulatum Burm. f., A. peruvianum Klotzsch, and A. venustum D. Don. Standard methods for macro-microscopic evaluation, physicochemical parameters and HPTLC were used for authentication and identification. The salient distinctive characters under the microscope are the presence of slightly wavy elongated epidermal cells in A. capillus-veneris; epidermal cells strongly wavy in A. lunulatum; star shaped epidermal cells and mixed spores of regular and irregular shaped in A. peruvianum; stomata on both the surfaces of pinnule, absence of spinulus spores only in A. venustum. In addition, rachis anatomy showed different cellular and stellar characteristics as identifying characters of aforesaid four Adiantum species. Physico-chemical parameters and HPTLC finger print profiles along with stigmasterol and lupeol play significant role for the quality evaluation of raw drugs. The above finding will serve the purpose of quality control and assurance for the future studies.