Monday, May 4, 2009
9-71
Extraction and Identification of Julibroside Saponins from the Bark of Albizia julibrissin
Abigail S. Engelberth, Chemical Engineering, University of Maine, 5737 Jenness Hall, Orono, ME 04469, Danielle Julie Carrier, Biological and Agricultural Engineering, University of Arkansas, Room 203 Engineering Hall, Fayetteville, AR 72701, and Edgar C. Clausen, Ralph E. Martin Department of Chemical Engineering, University of Arkansas, 3202 BELL, Fayetteville, AR 72701.
The co-generation of value-added products is one way of adding additional value to the biomass used in a biorefinery. One such product, saponins, can be found in the bark of Albizia julibrissin (mimosa). Saponins are a natural detergent that can be found in a variety of plants, ranging from Yucca schildigera in Mexico to Panax ginseng in China. Saponins contain both water-soluble and a fat-soluble components. Saponins have been shown to have antiprotozal activity in ruminals and have been shown to reduce blood cholesterol levels in mammals. Triterpenoidal saponins, julibrosides, are known to be present in Albizia julibrissin [1], and have previously been extracted with methanol and other organic solvents, separated by RP-HPLC and analyzed with mass spectrometry. Unfortunately, the julibrosides are not available commercially as reference compounds. Centrifugal partition chromatography (CPC) was used to separate and accumulate fractions of julibrosides for use as reference material. The reference fractions from the CPC were then used to find the most favorable parameters for pressurized hot water extraction of julibrosides from Albizia bark. The overall goal of this project was to determine the feasibility of extracting saponins, in a green manner, from mimosa biomass prior to conversion to a liquid fuel.
[1] Zou, K. et al. Diasteriomeric saponins from Albizia julibrissin. Carbohydrate Research. 2005, 340, 1329-1334