Alkaloids are a kind of important antibacterial components in plants. In order to explore its biological activity of alkaloids from kenaf bast fibres, the alkaloids were extracted from kenaf bast fibres and then its antibacterial activity has been evaluated in this study. The total content of crude alkaloids was 46.88 μg/g, and high performance liquid chromatography (HPLC) analysis revealed that the crude alkaloids extract mainly included berberine hydrochloride (6.42 μg/g) and other unknown components.The antibacterial testing results showed that the antibacterial effects of alkaloids on Staphylococcus aureus and Shigella dysenteriae was stronger than that of Escherichia coli. At the same concentration, the antibacterial effects of alkaloids extract of kenaf bast fibres was higher than that of berberine hydrochloride, which probably indicated that there were synergistic effect during antibacterial process among the components of alkaloids. In conclusion, kenaf bast fibres contains alkaloids and the alkaloids extract has good antibacterial activity.
Keywords: Kenaf bast fibres; alkaloids; antibacterial; biological activity.