Pressurized low polarity water (PLPW) extraction of cow cockle seed was carried out to determine the effect of extraction conditions (temperature (125-175 degrees C), time (15-180 min)), and sample pre-treatment on saponin yield and composition. Accelerated solvent extractions (ASE) and ultrasonic extractions (USE) using water, methanol and ethanol (50%, 80%, 100%) were also carried out to determine the effect of extraction solvent and method on saponin recovery. A higher saponin yield was obtained by ASE compared to USE using pure and aqueous ethanol and methanol. The highest saponin yield, which was obtained by ASE using 80% ethanol, was used to calculate saponin recoveries. The saponin yield of PLPW extracts increased with extraction temperature and time. While only 33.2 wt% of total saponins was extracted from ground seeds at 125 degrees C in 3 h, 60.2 wt% was recovered in the first 15 min at 175 degrees C. Total extraction (I h) of whole seeds yielded more saponins than ground seeds at 125-160 degrees C. Saponin concentration of the extracts was affected by the extraction solvent and method, sample pre-treatment and to a lesser extent by the time and temperature of PLPW extraction. The highest saponin concentration of PLPW extract was obtained at 125 degrees C using whole seeds (12%). The saponin composition of water extracts differed from that of aqueous ethanol and methanol extracts. Crown Copyright (c) 2006 Published by Elsevier Ltd. All rights reserved.