Histomorphology and HPTLC key identifying features of Sirunagapoo/Nagakesar (Mesua ferrea L. flower)

Abstract Background: The Sirunagapoo/Nagakesar ( Mesua ferrea L.) is a popular and well-known ASU medicinal plant part derived from the stamen of flowers. Different herbal markets of the country and online suppliers trade Mammea suriga (Buch.-Ham. ex Roxb.) Kosterm. and Calophyllum inophyllum L. flowers in the name of Sirunagapoo / Nagakesar . In Tamil Nadu, a mix of immature fruits of different Cinnamomum species is traded under the name of Sirunagapoo . As per Siddha Formulary of India, Cinnamomum wightii Meissn. is of official source of Sirunagapoo ; in Chennai markets, M. ferrea is also sold under the name of Sirunagapoo . There are four botanicals sold as Sirunagapoo/Nagkesar leading to confusion in identifying the correct source. This study is aimed at carrying out comparative studies of macroscopy and anatomy in whole form as well as powder and pharmaceutical dosage forms like formulations in powdered form, tablets, or any compound formulation having this raw drug employing powder microscopy and thin-layer chromatography (TLC)/high-performance TLC (HPTLC). Materials and Methods: All the studies were carried out following Siddha Pharmacopeial procedures. Results: Macroscopic observations of the whole flowers and anatomy of calyx, corolla, gynoecium, and anther were documented. Powder microscopically, the drug showed characters such as trichomes, sclereids, stomata, xylem elements, fibers, brownish content, lysigenous cavities, oil globules, pollen grains, and different sizes of calcium oxalate crystals which will help in the identification of this raw drug in powder form also. HPTLC has shown a unique pattern for differentiating the bands in methanol extract. Conclusion: This study will be helpful to distinguish and identify the correct botanical source of Sirunagapoo/Nagakesar ( M. ferrea ) as single drug or as powder form added to a formulation as one of the ingredients.