Antifungal Activity of Phytochemicals against Samples of Penicillium

Aims: The incidence of fungal infections has increased over the last ten years and fungi of the genus Penicillium can be found in various substrates and affect immunocompromised people, hospitalized patients, many animals and plants, as well as compromise the quality of air indoors. The current situation of indiscriminate use of antibiotics and the consequent resistance of microorganisms to conventional antimicrobial therapy has been stimulating researchers to seek alternative sources of antimicrobial compounds, among them the medicinal plants. The tendency of getting phytochemicals from extracts, fractions, fixed or essential oils obtained from plant species is currently observed. In this context, the present study aims to evaluate the in vitro antifungal activity of seven phytochemicals (geraniol, carvacrol, thymol, linalool, p-cymene, terpinolene and citral) against twelve samples of Penicillium.

Place of Study: Laboratory tests were carried out at the Mycology Laboratory Department of Pharmaceutical Sciences, located in the Health Sciences Center (CCS) of the Federal University of Paraíba (UFPB).

Methodology: Firstly, screening was carried out to find the phytochemical with the best activity by determining the minimum inhibitory concentration (MIC) by the broth microdilution technique. Following, the tests were proceeded with thymol to determine of minimum fungicidal concentration (MFC).

Results: Through analysis of results, it is observed that carvacrol, thymol and citral showed the best activities of the samples of Penicillium studied. The MIC values were 256 mg/mL, for carvacrol and citral, and 128 mg/mL, for thymol (compound showed better results). The thymol had its MIC 90 established at 128 mg / mL, inhibiting, at this concentration, 92% of the tested samples. Analyzing compared to MIC and MFC, it was observed that thymol presented CFM values similar to CIM values for 1/3 of the samples, showing also values greater than 1024 mg/mL for only two samples. The CFM value ranged from 128 µg/ml to 1024 µg/ml.

Conclusion: The thymol is a promising new possibility among the products with antifungal activity against Penicillium, however if the performance is needed further studies, deeper, about their mechanism of action and toxicity, as well as in vivo tests, aiming a possible application therapy.