Figure 1.

Purification of peptides from Zizyphus jujuba fruit. A, Sephadex G-50 gel filtration of plant extract was applied on a Sephadex G-50 column equilibrated with phosphate buffer (0.1 mol/L, pH 6.0). B, The peak 4 (indicated with asterisk), with anticholinesterase activity from Sephadex G-50, was further purified on a C18 reverse phase-high-performance liquid chromatography (RP-HPLC) column. A 400-μL aliquot of filtrated extract from gel filtration was loaded onto a semipreparative C18 reverse phase column. Elution was performed using solution A (0.1% TFA in water), combined with a 5% to 65% gradient of solution B (0.098% TFA in acetonitrile) over a period of 70 minutes, at a flow rate of 1 mL/min. The absorbance was monitored at 220 nm, and the fractions were tested for anticholinesterase activity. The active peak has been indicated by an arrow. This peak was named Z (Zizyphus jujuba). TFA indicates trifluoroacetic acid.