KTI and BBI protease inhibitor in seed storage protein of Iranian soybean cultivars

Arefrad, Mehdi; Babaian Jelodar, Nadali; Nematzadeh, Ghorbanali; Dehestani, Ali; Gorji, Elahe

doi:10.22058/jpmb.2025.2048750.1324

KTI and BBI protease inhibitor in seed storage protein of Iranian soybean cultivars

Document Type : Original research paper

Authors

Mehdi Arefrad ¹

Nadali Babaian Jelodar ²

Ghorbanali Nematzadeh ²

Ali Dehestani ¹

Elahe Gorji ²

¹ Genetics and Agricultural Biotechnology Institute of Tabarestan (GABIT), Sari Agricultural Sciences and Natural Resources University (SANRU), Sari, Iran

² Department of Biotechnology, Sari Agricultural Sciences and Natural Resources University (SANRU), Sari, Iran

10.22058/jpmb.2025.2048750.1324

Abstract

Kunitz (KTI) and Bowman-Birk (BBI) protease inhibitors are considered the most significant factors that decrease the quality of soybean proteins. In this study, the levels of these proteins were investigated using the 2D-PAGE, and their activity was evaluated through trypsin and chymotrypsin proteases in ten Iranian soybean cultivars. These results indicated that the Katol cultivar has the lowest concentration of both KTI and BBI proteins and the lowest trypsin and chymotrypsin inhibitory levels. Therefore, this cultivar is an ideal choice for soybean protein-based diets and could also serve as a valuable parent in breeding programs aimed at improving protein quality in soybean . Moreover, no significant correlation was found between KTI with BBI proteins, nor between these proteins with protease activity. Therefore, it seems that genetic control targeting either KTI or BBI proteins alone may not be an effective approach to improving the quality of soybean proteins. Additionally, no correlation was found between KTI and BBI proteins with agronomic traits. This also suggests that reducing protease inhibitors in soybean proteins does not adversely affect overall soybean performance.

Keywords

Soybean

Kunitz protein

Bowman-Birk protein

trypsin inhibitor

chymotrypsin inhibitor

agronomic traits

Subjects

Plant biochemical and regulatory networks

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