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Animal Free, From Soybean Animal Free for sensitive chromatographic and analytical workflows requiring minimal baseline interference.
Store at 2-8°C Ships Wet ice Check lot-specific COA for exact specifications.
SDS, COA, datasheet, and spec sheet available for download. Lot-specific COA accessible via lot number lookup.
Cited in 5 peer-reviewed publications across chromatography, organic synthesis, and cross-coupling reactions.
Molecular weight: 21,500 ± 800 (Wu and Scheraga 1972a).
Optimum pH: 7.0.
Composition: The Kunitz soybean inhibitor consists of a single polypeptide chain crosslinked by two disulfide bridges (Steiner 1965). Structural studies of the inhibitor and active site have been reported, Ellis et al. (1975), Woodward and Ellis (1975), Koide et al. (1974), Koide and Ikenaka (1973), Bidlingmeyer et al. (1972), Ikenaka et al. (1971), Papaioannou and Liener (1970), Hixson and Laskowski (1970), Kato and Tominager (1970), and Wu and Scherage (1962). Donovan and Beardslee (1975) have reported on the thermal denaturation of inhibitor complexes.
Isoelectric point: 4.5 (Kunitz 1947).
Specificity: Soybean inhibitor inhibits trypsin mole-for-mole and to a lesser extent chymotrypsin. (Bidlingmeyer et al. 1972). Lanchantin et al. (1969) report soybean inhibitor to form a one-to-one complex with beef or human thrombin thus blocking its specific proteolytic capacity to activate prothrombin. Nanninga and Guest (1964) report plasmin to be inhibited. STI has been reported to inhibit leukocytic proteases. (Lieberman and Gawad 1971), but not the esterolytic, proteolytic or elastolytic activities of porcine elastase (Gertler and Feinstein 1971).
Soybean Trypsin Inhibitor (Kunitz):
Soybean trypsin inhibitor (SBTI) first crystallized by Kunitz (1945) is one of several such inhibitors found in soybeans. (Fratalli 1969; Millar et al. 1969; Fratalli and Steiner 1968; Birk et al. 1967). The best known preparation is that of Kunitz. Steiner and Fratalli (1969) have reviewed the Kunitz and Bowman-Birk inhibitors. A protein (or polypeptide) proteinase inhibitor probably has peptide bonds compatible with the protease reactive site. Finkenstadt and Laskowski (1965 and 1967) and Ozawa and Laskowski (1966) indicate that a single Arg-Ile bond is cleaved by trypsin; a covalent bimolecular complex of inhibitor and trypsin results. On dissociation either virginal or modified inhibitor appears; see Hixson and Laskowski (1970a), Isheda et al. (1970) and Niekamp et al. (1969).
Enzyme activity definition:
The activity of the inhibitors is expressed as the amount of twice crystallized trypsin (Aladdin Item: T128774) inhibited per milligram of inhibitor. 1mg trypsin ≥180 TAME units, 10,350 BAEE units, 3,450 USP/NF units.
| WGK Germany | 3 |
|---|---|
| Alternate CAS | 9035-81-1 |
Comprehensive hazard, handling, storage, and regulatory compliance document.
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| Lot Number | Certificate Type | Date | Item |
|---|---|---|---|
| Certificate of Analysis | May 18, 2026 | T113170 | |
| Certificate of Analysis | Mar 11, 2026 | T113170 | |
| Certificate of Analysis | Mar 11, 2026 | T113170 | |
| Certificate of Analysis | Dec 01, 2025 | T113170 | |
| Certificate of Analysis | Dec 01, 2025 | T113170 | |
| Certificate of Analysis | Dec 01, 2025 | T113170 | |
| Certificate of Analysis | Dec 01, 2025 | T113170 | |
| Certificate of Analysis | Sep 04, 2025 | T113170 | |
| Certificate of Analysis | Sep 04, 2025 | T113170 | |
| Certificate of Analysis | Jun 20, 2025 | T113170 | |
| Certificate of Analysis | Jun 20, 2025 | T113170 | |
| Certificate of Analysis | Jun 20, 2025 | T113170 | |
| Certificate of Analysis | Jun 10, 2025 | T113170 | |
| Certificate of Analysis | Apr 08, 2025 | T113170 | |
| Certificate of Analysis | Apr 08, 2025 | T113170 | |
| Certificate of Analysis | Apr 08, 2025 | T113170 | |
| Certificate of Analysis | Apr 08, 2025 | T113170 | |
| Certificate of Analysis | Jul 25, 2024 | T113170 | |
| Certificate of Analysis | Jul 25, 2024 | T113170 | |
| Certificate of Analysis | May 22, 2024 | T113170 | |
| Certificate of Analysis | Aug 15, 2023 | T113170 | |
| Certificate of Analysis | Aug 15, 2023 | T113170 | |
| Certificate of Analysis | Jul 06, 2023 | T113170 | |
| Certificate of Analysis | Jul 06, 2023 | T113170 | |
| Certificate of Analysis | Sep 02, 2022 | T113170 | |
| Certificate of Analysis | Sep 02, 2022 | T113170 | |
| Certificate of Analysis | Sep 02, 2022 | T113170 | |
| Certificate of Analysis | Mar 09, 2022 | T113170 |
| Solubility | balanced salt solution: 1 mg/mL;serum-free medium: soluble |
|---|
| 1. Fanping Shi, Lei Wang, Yan Li, Yu Zhang, Xingguang Su. (2017) A simple “turn-on” detection platform for trypsin activity and inhibitor screening based on N-acetyl-l-cysteine capped CdTe Quantum Dots. SENSORS AND ACTUATORS B-CHEMICAL, [PMID:] [10.1016/j.snb.2017.09.087] |
| 2. Wei-Xian Wang, Yuqing Wu, Hong-Wei Li. (2017) Regulation on the aggregation-induced emission (AIE) of DNA-templated silver nanoclusters by BSA and its hydrolysates. JOURNAL OF COLLOID AND INTERFACE SCIENCE, [PMID:28646761] [10.1016/j.jcis.2017.06.033] |
| 3. Xiu Huang, Yong Li, Zhao Shu, Li Huang, Qian Liu, Guibin Jiang. (2024) High-Efficiency Degradation of PET Plastics by Glutathione S-Transferase under Mild Conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY, [PMID:39012182] [10.1021/acs.est.4c02132] |
| 4. Fan Yanan, Xu Qixiang, Ren Keyu, Zhai Mengge, Xing Guozheng, Song Yishan, Zhu Yongheng. (2024) Research on pH-responsive Antibacterial Materials Using Citral-modified Zinc Oxide Nanoparticles. Food Quality and Safety, [PMID:] [10.1093/fqsafe/fyae010] |
| 5. Xiu Huang, Li Huang, Qian Wang, Qiurong He, Zunzhen Zhang, Qian Liu, Guibin Jiang. (2025) High-efficiency enzymatic biodegradation of polypropylene-based melt-blown fabric debris. Chemical Science, [PMID:40708876] [10.1039/D5SC03097H] |
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