Abstract:

The experiment was designed to use erythrocytes for assaying the agglutinating activity of mung bean lectin,
and to improve the processing conditions for glutaraldehyde- and trypsin-treated rabbit red blood cells. Rabbit red blood
cells (RBC) were fixed with 0.15% (V/V) glutaraldehyde at 25 ℃ for 20 min, and the RBC were treated with trypsin
(25 U/mL) at 25 ℃ for 15 min to increase the assay activity and extend their preservation time. In the investigation, we
found that the most suitable extraction solvent for mung bean lectin was phosphate buffer solution. Based on the results of
single-factor experiments, a Box-Behnken design (BBD) of three variables at three levels each was carried out to obtain
maximum activity of mung bean lectin by response surface analysis. The maximum activity of mung bean lectin was
predicted to be 134.91 U/mg and observed to be 139.02 U/mg under the optimum extraction conditions: solid-to-liquid ratio,
1:9.09 (g/mL); NaCl concentration, 0.3 mol/L; and extraction time, 4.16 h.

Key words: mung bean lectin, response surface analysis, optimization, extraction