Influence of γ-Radiation on the Structure and Function of Soybean Trypsin Inhibitor

Abstract

Soybean trypsin inhibitor (STI) is a known antinutrient and food allergen present in soybean. γ-Radiation has the potential to inactivate the TI protein. However, a systematic study on the influence of different moisture levels during γ radiation on structure and function of the molecule has not been reported. Pure STI was irradiated up to 200 kGy, in dry state, with 50% moisture and in aqueous solution. The radiation damage in molecular structure was assessed using, SDS-PAGE, size exclusion chromatography, fluorescence measurement, and circular dichroism, while functional damage was assessed by the TI assay. In aqueous solution, both the structure and function of TI were almost destroyed at the 10 kGy dose. While with 50% moisture and in dry state, the loss in functional and structural attributes was discernible only at 30 and 100 kGy, respectively. The TI activity was found to be unaffected in dry and soaked seeds of soybean as well as other legumes up to irradiation doses of 100 and 50 kGy, respectively.

Selenium substitution endows cystine with radiosensitization activity against cervical cancer cells

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Potential allergenicity response to structural modification of irradiated bovine α-lactalbumin

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