Biosynthesis of the phycocyanin β-subunit in Escherichia coli BL21 and its antioxidant activity and application in the preservation of fresh-cut apples

Int J Biol Macromol. 2024 Feb;258(Pt 1):128951. doi: 10.1016/j.ijbiomac.2023.128951. Epub 2023 Dec 22.

Abstract

In this study, the biosynthesis of phycocyanin β-subunit (CpcB) in Escherichia coli BL21 was investigated, and its antioxidant activity and application in anti-browning of fresh-cut apples was explored. Four genes (cpcB, cpeS, hox1 and pcyA) involved in the biosynthesis of CpcB were cloned and transformed into E. coli BL21 by constructing recombinant plasmid pETDuet-5. The positive transformant was screened by ampicillin resistance. The analysis of SDS-PAGE and zinc fluorescence spectrum showed that CpcB was successfully expressed in E. coli BL21 with a molecular weight of 21 kDa. The purified CpcB had a maximum absorption peak at 615 nm, and its maximum florescence emission wavelength was 640 nm. It exhibited a stronger ability to scavenge four free radicals than Vc. The color change in fresh-cut apples was obviously delayed by the CpcB treatment. These results suggest that CpcB may be used as a potential anti-browning agent for food preservation.

Keywords: Anti-browning; Antioxidant activity; Biosynthesis; Escherichia coli; Phycocyanin β-subunit.

MeSH terms

  • Antioxidants*
  • Escherichia coli / genetics
  • Malus*
  • Phycocyanin
  • Plasmids

Substances

  • Antioxidants
  • Phycocyanin