Localization of Saponins Accumulation in Yucca Gloriosa Variegata in Intact Tissues and Their Tissue Cultures by Using Fluorescence Microscopy

Abstract

Steriodal saponins are important active components of Yucca gloriosa Variegata, a medicinally important plant. The detection and localization of saponins accumulation is very necessary to determine which plant organ or tissue accumulates high levels of such important compounds. In this study, it has been reported for the first time the accumulation of saponins in leaves, rhizomes and shoot apex of Y. gloriosa Variegata and their in vitro cultured tissues (calli, direct and indirect regenerated shoots and rhizomes/roots) through histological sections using fluorescence microscope. This method presents fast and significant manner for saponins accumulation sites due to its high sensitivity and the selectivity of analyzing signals. Additionally, the intensity of fluorescence distinguishes the level of saponins in these tissues. Specimens were fixed, embedded in paraffin, and stained with aniline blue (390 nm excitation and 480 nm emission) then viewed with BX53 (Olympus)fluorescence microscope. Photographs were taken using a high sensitivity digital camera. Results showed high level of saponins accumulation appeared particularly in indirect regenerated leaf (initiated from callus cultures) and in callus treated with Thidiazuron (TDZ). Saponins content was variable during different periods of callus growth.