The leaves of Boscia senegalensis are traditionally used in West Africa in cereal protection against pathogens, pharmacologic applications, and food processing. Activities of α-amylase, β-amylase, exo-(1-->3, 1-->4)-β-D-glucanase, and endo-(1-->3)-β-D-glucanase were detected in these leaves. The endo-(1-->3)-β-D-glucanase (EC 184.108.40.206) was purified 203-fold with 57"ield. The purified enzyme is a nonglycosylated monomeric protein with a molecular mass of 36 kDa and pI ≥ 10.3. Its optimal activity occurred at pH 4.5 and 50°C. Kinetic analysis gave Vmax, kcat, and Km values of 659 U/mg, 395 s-1, and 0.42 mg/mL, respectively, for laminarin as substrate. The use of matrix-assisted laser desorption ionization time-of-flight mass spectrometry and high-performance liquid chromatography revealed that the enzyme hydrolyzes not only soluble but also insoluble (1-->3)-β-glucan chains in an endo fashion. This property is unusual for endo-acting (1-->3)-β-D-glucanase from plants. The involvement of the enzyme in plant defense against pathogenic microorganisms such as fungi is discussed.
Dicko, M. H., Searle-van Leeuwen, M. J., Traore, A. S., Hilhorst, M. H., & Beldman, G. (2001). Polysaccharide hydrolases from leaves of Boscia senegalensis: properties of endo-(1-->3)-beta-D-glucanase. Applied Biochemistry and Biotechnology, 94(3), 225-241. https://doi.org/10.1385/ABAB:94:3:225