Pectic Polysaccharides from Pumpkin Fruit
ZK Muhidinov1, AS Djonmurodov1, SE Kholov1, RM Gorshkova1, ML Fishman2, LS Liu2
1Chemistry Institute of Tajikistan Academy of Sciences, Dushanbe, Tajikistan
2Eastern Regional Research Center ARS USDA 600 East Mermaind Lane, Wyndmoor 19038 PA, USA.
Steam assisted flash extraction (SAFE)1 of pectic polysaccharides (PP) obtained from pumpkin matrices (PM) was studied. PP composition, molar mass and molar mass distribution (MMD) was measured2. Analysis revealed that the degradation of PM occur by a combination of parallel and sequential hydrolysis reactions3. Both macromolecular association and dissociation occur during PM hydrolysis and extraction of PP. It is shown that pumpkin PP consist of two subunit fractions, one of high and the other of low molar mass. Molar mass measurements indicate that both sub unit fractions were either mono disperse or narrow distributions. Conformation plot analysis of both fractions clearly shows pectin molecules with rod like and elongated shape (swelled coil) conformations, respectively. The first high molar mass fraction was a coil with a folded conformation (b = 0.29). The low molar mass PP fraction was found to be a linear chain with a rigid conformation (b = 0.94). High values of intrinsic viscosity and hydrated radius of PP show a predominance of linear structures in the first fraction. The results demonstrated that the optimized SAFE extraction process provides a background for the development of processing of untapped sources of pectin.
Reference
EA Patent 016871. Process for sunflower pectin production, (05/06/2009). Publication data August, 30, 2012. Muhidinov Z.K., Fishman M.L., Liu LS.
2 Muhidinov Z.K., Teshaev Kh., Jonmurodov A., Khalikov D. and Fishman M. (2012). Physico-chemical characterization of pectic polysaccharides from various sources obtained by steam assisted flash extraction (SAFE). Macromolecular Symposia, volume 317-318, issue 1, p.142-148.
3 Khalikov D.Kh., Mukhiddinov Z.K. (2004). Physicochemical principials of the plant cell walls protopectin decomposition by acid catalysts, a review- Chem. of Natural Compounds., vol.40 (No 2), p. 101-114.