Purification And Characterization Of An Antimicrobial Peptide From Ginkgo Biloba Seeds And Isolation Of Ginkgo Biloba Seed Total RNA

The Antimicrobial peptides are acturally small peptides which can restain bacterium,fungi, insect cells, plant cells and animal cells. We can also call them Peptide antibiotics orNatural antibiotics. The research on Antimicrobial peptides can provide candidates forfiltering anti anticancer and antivirus medicament. The targets of the experiment are topurifying an Antimicrobial peptide from Ginkgo biloba seeds , to analyzing it's qualities andestablish an RTPCRsysterm for Ginkgo biloba seeds. The whole work is the foundation ofit,s gene cloning and antimicrobil mechanism in molecularthe level.Using the seeds of ginkgo biloba as experiment material, an antimicrobial peptide isobtained by three methods. We also analyse it's qualities of molecular weight, antimicrobialactivity, hot stability, extreme pH value stability and high salt concentration stability. We alsoobtain the total RNA of the Ginkgo biloba seed by four methods and establish an RTPCRsysterm.The following results was obntained:1 An antimicrobial peptide is obtained by three methods. In SDSPAGEthe peptideappears as a single band with a molecular weight is 13000 Da. The peptide obtained fromAKTA systerm appears as a single dot in 2Dspectrum.2 The peptide can be eluted from the CM ion exchange chromatography by high saltconcentration elution, so it is a basic peptide. It's isoelectric point is 9.8 according to it's 2Dspectrum.3 The peptide exerted potent antifugal activity against 14 fungi, including Fusariumoxysporum, Fusariumgraminearum,Botrytis cinerea, Cloeosporium orbiculare andFusarium oxysporium.4 The peptide appears atrong antifugal activity when its concentration is 2.5 mg/ml. Thepeptide has high hot stability, and it shows strong antifugal activity against Fusariumoxysporum when heating at 90℃for 30 minutes. it also shows strong antifugal activityaagainst Fusarium oxysporum in acidic circumstance. And the peptide exhibite a moderateantibacterial action against staphylococcus aureus and Escherichia Coli.5 The total RNA isolated by CTAB methode is with good quality, high purity andquantity. It is quite fit for the RTPCR.