Cellulase-assisted extraction of polysaccharides from Cucurbita moschata and their antibacterial activity

In this study, cellulase-assisted extraction of water soluble polysaccharides from pumpkin (Cucurbita moschata) and their antibacterial activity were investigated. The polysaccharides yield was monitored during the extraction process. The optimum extraction conditions were determined as follows: time, 40 min; temperature, 55 C; pH, 4.5; and cellulase amount, 4000 U/g. The extracts were centrifuged, filtered, proteins removed by Sevag method, concentrated to similar to 15% (w/v), precipitated with 5 volumes of absolute ethanol, freeze-dried, and pulverized to yield a water soluble powder of pumpkin polysaccharides (PP). The sugar content of the product was 68.3%, and the yield was 17.34% (w/w), respectively. The PP had high antibacterial activity against Bacillus subtilis, Staphylococcus aureus, and Escherichia coli at the concentration of 100 mg/mL. (C) 2013 Elsevier Ltd. All rights reserved.