Chemical, antioxidant and cytotoxic profile of hydroalcoholic extracts of plants from Southern Brazil and their activity against pathogenic fungi isolated from dogs and cats with sensitivity and resistance to conventional antifungals

Nat Prod Res. 2022 Jun;36(12):3223-3228. doi: 10.1080/14786419.2021.1956920. Epub 2021 Sep 9.

Abstract

We aimed to evaluate the chemical, antioxidant, cytotoxic, and antifungal activities of hydroalcoholic extracts of native plants from Southern Brazil: Schinus terebinthifolia (SCH), Persicaria hydropiperoides (PER), Eugenia uniflora (EUG) and Equisetum hyemale (EQU). Ethyl gallate, quercetin, and quinic acid were prevalent compounds identified by LC-MS. For total phenolic/flavonoid contents and the antioxidant potential against ABTS/DPPH radicals, the ascending order was EQU < PER < EUG < SCH. All extracts were low cytotoxic and kept a high Vero cell viability (>75%) at concentrations up to 12.5 mg/mL (MTT assay). By M38-A2/M27-A3 (CLSI) against 68 clinical isolates of animals and strains of Malassezia pachydermatis, Sporothrix brasiliensis, Microsporum canis, Microsporum gypseum and Trichophyton mentagrophytes, all extracts (MIC/MFC ≤3.13-100 mg/mL) were active, except EUG. SCH inhibited and killed S. brasiliensis (MIC/MFC50/90 3.12-12.5 mg/mL) and dermatophytes (MIC/MFC 6.25-25 mg/mL) resistant to ketoconazole and itraconazole. These findings support the promising use of the selected plant extracts as antifungal agents.

Keywords: Equisetum hyemale; Eugenia uniflora; Malassezia pachydermatis; Persicaria hydropiperoides; Schinus terebinthifolia; Sporothrix brasiliensis; dermatophytes.

MeSH terms

  • Animals
  • Antifungal Agents / chemistry
  • Antioxidants / pharmacology
  • Brazil
  • Cat Diseases*
  • Cats
  • Dog Diseases*
  • Dogs
  • Microbial Sensitivity Tests
  • Plant Extracts / chemistry

Substances

  • Antifungal Agents
  • Antioxidants
  • Plant Extracts