Abstract:

An antifungal peptide (AFP) having the ability to protect organisms against fungal invasion was isolated from tartary buckwheat (Fagopyrum tataricum) seeds. The purification procedure involved extraction with 20 mmol/L Tris-HCl buffer, heating treatment, Resource S cation exchange column chromatography, and size exclusion chromatography (SEC) on Superdex peptide column. The apparent molecular weight of the purified peptide was approximately 8.0 kD evaluated by Tricine-SDS-PAGE, and its actual molecular weight was 3.909 kD determined by surface-enhanced laser desorption ionization- time of flight (SELDI-TOF). This peptide showed strong antifungal activity against Panus conchatus, Trichoderma reesei and Alternaria alternate and could cause swelling hyphal tips, hyphal distortion and condensed protoplasm in Trichoderma reesei. The easy preparation, high thermal stability and potent antifungal activity of this antifungal peptide demonstrate its great potential in food industry.

Key words: tartary buckwheat (Fagopyrum tataricum), antifungal peptide, purification, antifungal activity, light microscopic examination, thermal stability