Apapun Kongcharoen1, Wannapun Poolex1, Thanaporn Wichai2, Ruethairat Boonsombat3. 1. Program in Biotechnology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand. 2. Institute of Biotechnology and Genetic Engineering, Chulalongkorn University, Bangkok, Thailand. 3. Institute of Biotechnology and Genetic Engineering, Chulalongkorn University, Bangkok, Thailand. ruethairat.b@chula.ac.th.
Abstract
OBJECTIVE: To circumvent the time-consuming and costly problems associated with natural product extraction, a potential antioxidative peptide selected from hairy basil waste after oil extraction was produced by recombinant DNA technology. RESULTS: Because the target peptide is short, the recombinant peptide containing seven repeats of the target sequence, QTFQYSRGWTN, and the DNA fragment coding this sequence was cloned into the pQE-30 Xa expression vector and transformed into Escherichia coli. After 6 h of recombinant peptide expression in E. coli, the target peptide was purified by Ni(2+) affinity chromatography and gel extraction. The expected 15 kDa recombinant target peptide construct was verified by modified dot blot analysis. Compared with the chemically synthesized peptide, the recombinant peptide revealed significantly higher antioxidant activities (p < 0.05), as determined by DPPH and ABTS radical scavenging assays, and in vitro DNA damage induced by hydroxyl radicals. CONCLUSION: This approach provides an alternative to produce an antioxidative peptide that provides a potential scaffold for the further development of antioxidative peptides for industrial applications.
OBJECTIVE: To circumvent the time-consuming and costly problems associated with natural product extraction, a potential antioxidative peptide selected from hairy basil waste after oil extraction was produced by recombinant DNA technology. RESULTS: Because the target peptide is short, the recombinant peptide containing seven repeats of the target sequence, QTFQYSRGWTN, and the DNA fragment coding this sequence was cloned into the pQE-30 Xa expression vector and transformed into Escherichia coli. After 6 h of recombinant peptide expression in E. coli, the target peptide was purified by Ni(2+) affinity chromatography and gel extraction. The expected 15 kDa recombinant target peptide construct was verified by modified dot blot analysis. Compared with the chemically synthesized peptide, the recombinant peptide revealed significantly higher antioxidant activities (p < 0.05), as determined by DPPH and ABTS radical scavenging assays, and in vitro DNA damage induced by hydroxyl radicals. CONCLUSION: This approach provides an alternative to produce an antioxidative peptide that provides a potential scaffold for the further development of antioxidative peptides for industrial applications.