1. Isolation of cicadin, a novel and potent antifungal peptide from dried juvenile cicadas
Hexiang Wang, Tzi Bun Ng Peptides. 2002 Jan;23(1):7-11. doi: 10.1016/s0196-9781(01)00573-3.
A single-chained antifungal protein with a molecular weight of 6.5 kDa and displaying a novel N-terminal sequence was isolated from dried juvenile cicadas which are used in traditional Chinese medicine, by using ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, ion exchange chromatography on SP-Sepharose and then gel filtration on a Superdex peptide column. The peptide, designated cicadin, exerted potent antifungal activity with IC(50) values at nonomolar concentrations against a variety of fungi including Botrytis cinerea, Mycosphaerella arachidicola, Fusarium oxysporum, Rhizoctonia solani and Coprinus comatus. Cicadin suppressed the activity of HIV-1 reverse transcriptase and stimulated the proliferation of murine splenocytes.
2. Isolation of allicepin, a novel antifungal peptide from onion (Allium cepa) bulbs
H X Wang, T B Ng J Pept Sci. 2004 Mar;10(3):173-7. doi: 10.1002/psc.509.
From the bulbs of the onion Allium cepa, a novel antifungal peptide distinct from the antimicrobial peptide previously reported from onion seeds was isolated. The antifungal peptide, designated allicepin, was purified with a procedure that involved aqueous extraction, ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel and FPLC-gel filtration on Superdex 75. Allicepin was unadsorbed on DEAE-cellulose and adsorbed on Affi-gel blue gel. The molecular weight of allicepin was estimated to be 10 K by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration on Superdex 75. Allicepin exerted an inhibitory activity on mycelial growth in several fungal species including Botrytis cinerea, Fusarium oxysporum, Mycosphaerella arachidicola and Physalospora piricola.
3. An antifungal peptide from the coconut
H X Wang, T B Ng Peptides. 2005 Dec;26(12):2392-6. doi: 10.1016/j.peptides.2005.05.009.
A chromatographic procedure consisting of ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, ion exchange chromatography on CM-cellulose, and gel filtration by fast performance liquid chromatography on Supedex 75 was utilized to isolate a 10 kDa antifungal peptide from coconut flesh. The peptide was unadsorbed on DEAE-cellulose, but adsorbed on Affi-gel blue gel and CM-cellulose. It displayed antifungal activity against Fusarium oxysporum, Mycosphaerella arachidicola and Physalospora piricola. The IC50 values of its inhibitory activities on mycelial growth in M. arachidicola and HIV-1 reverse transcriptase activity were respectively 1.2 and 52.5 microM.
