Screening, Purification and Characterization of Anionic Antimicrobial Proteins from Foeniculum Vulgare

Abstract

Foeniculum vulgare Mill., commonly called fennel, is a medicinal plant belonging to the Umbelliferae (Apiaceae) family, and is used in traditional medicine. Antibacterial peptides were isolated using sodium phosphate citrate buffer and, for extraction, cetyltrimethyl ammonium bromide (CTAB) buffer with pH 6, have been employed and antimicrobial activity tested against four reference strains. The extracted protein was subjected to 3 kDa dialysis and separation was carried out by DEAE-ion exchange chromatography and further proteins were identified by 2D gel electrophoresis. The results of Foeniculum vulgare elutes obtained from DEAE-ion exchange chromatography were tested for antibacterial activity. Elute 3 shows the highest antibacterial activity on Pseudomonas aeruginosa with a diameter of a zone of inhibition of 16 mm and IC₅₀ value 25.02 (mcg/mL). Based on the findings of the wide usage in treatment of various ailments and day-to-day life, Foeniculum vulgare seeds were used in the present research and have shown promising antibacterial effects, which requires further proteomic research to authenticate the role of the anticipated proteins.

Keywords: Foeniculum vulgare; antimicrobial proteins; ion exchange chromatography.

Figure 1

The photograph shows the antimicrobial activity of Foeniculum vulgare extracted in sodium acetate buffer at a pH of 6.5 after dialysis. In this figure, ‘1’ indicates protein from Foeniculum vulgare and ‘S’ indicates standard antibiotic-Ciprofloxacin (100 mcg/mL). (i) S. aureus; (ii) E. coli; (iii) P. aeruginosa; and (iv) P. vulgaris.

Figure 2

The diameter of the zone of inhibition of ion exchange chromatography elutes from Foeniculum vulgare. S. aureus (i), E. coli (ii), P. aeruginosa (iii), and P. vulgaris (iv). A, B, C, and D represent elutes 1, 2, 3, and 4, respectively.

Figure 3

The protein spots of elute 2 obtained after ion exchange chromatography. Marker used: Biorad Prestained SDS-PAGE Standard, Broad Range. IEF strip pH 3–10 linear, 17 cm.