Planta Med 2014; 80 - PV2
DOI: 10.1055/s-0034-1382764

Calcium oxalate crystals in Dioscorea (Dioscoreaceae)

V Raman 1, IA Khan 1, 2
  • 1National Center for Natural Products Research, School of Pharmacy, University of Mississippi, University, MS 38677, USA
  • 2Department of Pharmacognosy, School of Pharmacy, University of Mississippi, University, MS 38677, USA

Calcium oxalate crystals are common in higher plants. They occur in five major forms namely crystal sand, raphide, druse, styloid and prismatic. The shape and occurrence of the crystals are species-specific hence considered as an important taxonomic characteristic. The present study investigates various forms and shapes of crystals found in the tubers and rhizomes of different species of Dioscorea. Raphide crystals are abundant in yams, and different shapes as well as unusual aggregations of raphide crystals are observed and discussed in this study. Other forms of crystals such as druces, styloids and prisms are also observed and illustrated.