Study on morphological and microscopic characteristics of Trong lau cao bang (Paris caobangensis) in Vietnam

Abstract

Paris caobangensis Y. H. Ji, H. Li, Z. K. Zhou was first recorded in Cao Bang in Vietnam. Like other species in the Paris genus, rhizome of Paris caobangensis has been intensively exploited in recent years for valuable traditional herbal medicine - ‘Trong Lau’. However, up to now, there has been no detailed study on morphological and microscopic characteristics of this species. In this study Paris caobangensis (collected in Cao Bang, Lao Cai, Lai Chau province) has been characterized morphological, anatomical structure and crude drug powder. Paris caobangensis differs from the two species has been adopted as ‘Chong Lou’ medicinal materials in Chinese Pharmacopoeia (2020) - Paris chinensis and Paris yunnanensis in leave ovate, basal truncate to cordate; petals 1 - 2 mm in width, shorter than 2/3 sepals; ovary 4 - 5 sides, cros; raphides arranged both in the form of vertical and radial, measuring 100 - 280 x 2 - 4 µm; starch grains ellipsoidal, spheroidal 5 - 11 x 7 - 17 µm.