Alim26667 Vol. 25 No. 1 (2026)

Vol. 25, No. 1 (2026), Alim26667 https://doi.org/10.24275/rmiq/Alim26667

Amylases from malted barley (Hordeum vulgare) seeds separated by aqueous two-phase extraction

Authors

G. Vega-Ramírez, S. Valle-Guadarrama, B. E. Hernández-Rodríguez, O. Sandoval-Castilla

Abstract

Germination promotes the production of amylases, making seeds at such stage a source of these enzymes. The objective was to separate amylases from malted barley (Hordeum vulgare L.) seeds by aqueous two-phase extraction to facilitate their use in industrial processes. The germination of barley seeds was monitored, showing an increase in protein and enzymatic activity up to maximum values at 42 h, coinciding with a reduction in starch from 63.68 to 48.45%. A mixture of potassium phosphate (PP) and polyethylene glycol 2000 (PEG 2000) was studied to separate amylases by aqueous two-phase extraction. The mixture of 22.03% PP and 17.29% PEG 2000 was chosen, which allowed the enzymes to be recovered in the top polymeric phase, with a yield of 63.92% and a purification factor of 5.82. The enzyme activity was influenced by temperature, pH, and starch concentration, with maximum values of 1.57, 1.81, and 0.98 U mL-1 at 40 °C, 5.0, and 0.5%, respectively. The kinetic activity of the amylolytic enzymes was expressed through a Michaelis-Menten model and the effect of inhibition by substrate was discussed. The feasibility of separating amylases from barley germinated seeds through aqueous two-phase extraction was demonstrated.

Keywords

Hordeum vulgare L., aqueous two-phase extraction, amylases, barley, germination.

References
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Gu, Z., Rao, J. and Chen, B. (2025). Application of flavoromics approach to evaluate aroma characteristics in malts: Current trends and future outlooks. Trends in Food Science & Technology, 156, 104878. https://doi.org/10.1016/j.tifs.2025.104878
Gupta, N., Paul, J.S. and Jadhav, S.K. (2024). Chitosan decorated magnetic nanobiocatalyst of Bacillus derived α-amylase as a role model for starchy wastewater treatment, detergent additive and textile desizer. Bioorganic Chemistry, 151, 107673. https://doi.org/10.1016/j.bioorg.2024.107673
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