MYCOLab Ai Logo - gold and army green

Valorization of Quercus suber L. Bark as a Source of Phytochemicals with Antimicrobial Activity against Apple Tree Diseases

Summary

This research shows that waste cork from bottle stopper production contains natural compounds with strong antimicrobial properties. When combined with chitosan oligomers, these cork extracts effectively inhibit fungal and bacterial pathogens that damage apple trees. The natural antimicrobial activity was even more potent than some commercial synthetic fungicides, suggesting cork waste could provide an environmentally sustainable alternative for protecting fruit crops.

Background

Cork oak bark processing generates large waste streams of cork fragments and dust. Cork contains various bioactive compounds with potential antimicrobial properties. This study explored the valorization of cork waste as a source of phytochemicals to inhibit phytopathogenic microorganisms associated with apple tree diseases.

Objective

To assess the in vitro antimicrobial activity of aqueous ammonia extracts of Quercus suber bark, alone and in combination with chitosan oligomers, against fungal and bacterial pathogens of apple trees. The study aimed to identify main phytochemical constituents and evaluate protective efficacy in ex situ bioassays.

Results

The cork extract contained glycerin (7.7%), vanillic acid (3.3%), and other bioactive compounds. EC₉₀ values ranged from 675-3450 μg·mL⁻¹ for fungal pathogens, substantially improved to 340-801 μg·mL⁻¹ in conjugate complexes with chitosan oligomers. Antibacterial MIC values were 375 and 750 μg·mL⁻¹ for conjugate complexes. The COS-bark extract complex achieved high protection at 3750 μg·mL⁻¹ in ex situ stem tests.

Conclusion

Cork industrial waste represents a promising source of bioactive compounds with antimicrobial activity superior to some commercial fungicides. The synergistic effects with chitosan oligomers enhance efficacy. These results support the potential use of cork extracts in integrated pest management for apple tree disease control.
  • Published in:Plants (Basel),
  • Study Type:Experimental Study,
  • Source: PMID: 36559527; DOI: 10.3390/plants11243415
Scroll to Top