In vitro bioassay guided anti-dermatophyte and cytotoxic activities from Piper umbellatum L. Miq. led to 4-nerolidylcatechol.

Dermatophytosis is a dermic disease caused by fungi. The aim of this study was to search anti-dermatophyte bioactive compounds in Piper umbellatum leaves. Cytotoxicity evaluation was performed against MRC-5 and HepG2 as a selectivity parameter. Crude ethanol extract presented MIC value of 39.1 µg/mL against M. canis and no cytotoxicity to Hep G2 (human liver cancer) and MRC-5 (normal lung fibroblast). 4-nerolydilcatechol was isolated from P. umbellatum ethanolic extract. MIC values for 4-NC were 7.6µM to M. canisand 15.6µM to Trichophyton rubrum. 4-NC presented activity against M. canis14 times lower than to MRC-5 (non-tumoral human cell line), which suggest selective activity for this fungus. Molecular modeling suggests 4-NC could bind to CYP51, present in lanosterol synthesis, blocking fungi development. In conclusion, P. umbellatum crude ethanol extract and 4-NC demonstrated high and selective in vitro antifungal activity.[Formula: see text].

Antifungal, antiradical and cytotoxic activities of extractives obtained from Tagetes patula L. (Asteraceae), a potential acaricide plant species.

Tagetes patula L. shows a complex chemical composition, ranging from glycosylated flavonoids and thiophenes in extracts until terpenoids in the essential oil. In the present study, due to this rich flavonoidic constitution, its antioxidant potential was determined, having shown values of antiradical percentage superior to reference compounds, mainly the extracts prepared with flowers. Previous studies performed emphasized the acaricide potential of T. patula and thus, the present study aimed to verify the action of extractives obtained from aerial parts on growth of entomopathogenic fungi related to biological control of brown dog tick Rhipicephalus sanguineus and the action against pathogenic fungi closely associated with pets. None of the samples inhibited the growth of strains of Beauveria bassiana or Metarhizium anisopliae, enabling feasible future studies of synergism on acaricide activity of formulations containing fungi and extracts. The antimicrobial activity of ethanolic extract of flowers (FlEtOH70%) against Microsporum canis and Trichophyton rubrum was significant (193.3 µg/mL and 253.9 µg/mL, respectively), as well as ethanolic extract from aerial parts (APEtOH70%) against T. rubrum (312.5 µg/mL). In order to ensure the safety of a topical formulation containing the extractives of T. patula, the cytotoxic potential of these samples were tested in murine macrophages cells. At higher concentrations all extracts were quite lethal, with IC50 ranging from 210.96 µg/mL to 468.75 µg/mL for APEtOH70% and FlEtOH70%, respectively. These results suggest that the application of a product containing T. patula extractives in the control of ticks could be used, at principle, only on the environment.

Phytochemical Characterization, Antimicrobial Activity, and Antioxidant Potential of Equisetum hyemale L. (Equisetaceae) Extracts.

Equisetum hyemale species is considered a medicinal plant used in the form of infusions to combat infectious or inflammation diseases and also diuretic effects, presenting several compounds related to these actions. In previous studies different species of Equisetum showed several phenolic compounds. The objective of this study was, for the first time, based on phytochemistry analysis to evaluate the antioxidant and antimicrobial activity. The 70% ethanolic and methanolic extracts of E. hyemale were characterized by spectrophotometric and high-performance liquid chromatography with pulsed amperometric detector analyses, as well as its antioxidant potential based on the scavenger activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH). In addition was verified the antimicrobial activity by broth microdilution technique against bacteria and fungi. The extracts showed phytochemical similarity, which demonstrated the presence of phenolic compounds, the scavenging activity for free radicals was about 30% and was observed better antifungal activity against dermatophyte fungi, with minimum inhibitory concentration and minimum fungicidal concentration of 0.62 mg/mL to Trichophyton rubrum and Microsporum canis. The extracts exhibits great potential to therapeutic applications or product development, since both possess antifungal activity and antioxidant action associated with little difference in their phytochemical composition.