Anti-inflammatory and antioxidant properties of unripe papaya extract in an excision wound model

Pharm Biol. 2015 May;53(5):662-71. doi: 10.3109/13880209.2014.936470. Epub 2014 Nov 28.


Context: Carica papaya L. (Caricaceae) fruit was shown to exhibit wound healing properties.

Objectives: We investigated anti-inflammatory and antioxidant potential of papaya fruit phosphate-buffered saline extract (PE) during wound healing and enhancement of the potentials due to trace ions addition.

Materials and methods: Rat excision wounds were topically treated twice/day with 20 µL of PE (5 mg extract/mL), 0.5 µg Se(2+) added PE (PES), or 100 µM Zn(2+) added PE (PEZ). Control groups were treated with deionized water (negative) and deproteinized calf blood extract ointment (Solcoseryl®, positive). Lipid peroxidation (LPX), antioxidant, proinflammatory, and arginine metabolic enzymes were estimated in the wound excised on days 4 and 10 post wounding.

Results: PE (5 mg/mL; 9.80 ± 0.33 d) and PES (PE + 0.5 µg Se(2+); 8.90 ± 0.23 d) significantly (p < 0.05) reduced the average time for complete wound closure compared with the negative (13.00 ± 0.37 d) and positive (9.80 ± 0.33 d) controls, respectively. Biochemical evaluations of LPX product (malondialdehyde), antioxidant (catalase, superoxide dismutase (SOD), and glutathione peroxidase (GPx)), and pro-inflammatory (cyclooxygenase-2 and myeloperoxidase (MPO)) enzyme activities and metabolites (nitrite and urea), on days 4 and 10 post wounding, confirmed the anti-inflammatory and antioxidant properties of PE and PES in this study.

Discussion and conclusion: Treatment of excision wounds with papaya extract, especially with the addition of selenium for 10 d, reduced inflammation associated oxidative damage apparently via cyclooxygenase specific inhibition, arginine metabolism, and up-regulation of antioxidant enzymes.

Keywords: Antioxidant enzyme; arginine metabolism; lipid peroxidation; proinflammatory enzymes; selenium; wound healing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Inflammatory Agents / isolation & purification
  • Anti-Inflammatory Agents / pharmacology*
  • Antioxidants / isolation & purification
  • Antioxidants / pharmacology*
  • Carica*
  • Cattle
  • Female
  • Fruit*
  • Lipid Peroxidation / drug effects
  • Lipid Peroxidation / physiology
  • Plant Extracts / isolation & purification
  • Plant Extracts / pharmacology*
  • Rats
  • Rats, Sprague-Dawley
  • Wound Healing / drug effects*
  • Wound Healing / physiology


  • Anti-Inflammatory Agents
  • Antioxidants
  • Plant Extracts