Extraction of saponins and cyclopeptides from cow cockle seed with pressurized low polarity water

Pressurized low polarity water extraction of whole cow cockle seeds was carried out at 160 °C to determine the effect of flow rate (0.5, 1, 2, 4, and 8 mL/min), flow direction (upward and downward flow), and sample size (3 and 6 g) on the recovery of saponins and cyclopeptides. Extraction rate increased whereas loading of the solvent (in the constant rate period) decreased with flow rate. Sample size did not have an effect on total recovery. Similarly, flow direction did not affect total recovery, but extraction of 6 g seeds using upward flow resulted in considerably higher extraction rates early in the extraction. The effect of flow direction was more pronounced for cyclopeptide extraction. The higher extraction rates (lower extraction times) that were attained at higher flow rates were accompanied by increases in solvent to feed ratio and thus less concentrated extracts.