ACTIVE SOYBEAN LECTIN IN FOODS - ISOLATION AND QUANTITATION

An improved method was developed to determine active soybean lectin in processed foods containing soybean. Freeze drying of crude extracts followed by affinity chromatography allowed the authors to purify and quantitate active lectin. After dialysis, concentrated extracts from products were loaded on to a chromatography column of immobilized N-acetyl-galactosamine. Active lectin content of soybean flours depended on the processing method used. The highest level found was for raw seeds (3600 μg/g), and the lowest for texturized flour (12·9 μg/g). Direct human consumption foods contained various lectin concentrations. While meat substitutes were free of active lectin, milk substitutes, and bakery products had low levels. A cereal type food and a cookie showed the highest lectin concentrations (187·2 and 24·2 μg/g, respectively). © 1990.