Antifungal activity of some Sternbergia taxa: effects on germ tube and biofilm formation

• Published in: Brazilian Journal of Pharmaceutical Sciences Vol. 55
• Main Authors: Kaskatepe, Banu, Yilmaz, Betul Sever, Acikara, Ozlem Bahadir, Iscan, Gulcin Saltan, Vlainic, Josipa, Kosalec, Ivan
• Format: Journal Article
• Language: English
• Published: Sao Paulo Universidade de Sao Paulo Faculdade de Ciencias 01-01-2019; Universidade de São Paulo, Faculdade de Ciências Farmacêuticas; Universidade de São Paulo
• Subjects: Analgesics; Antifungal activity; Antimicrobial agents; Biofilm inhibition; Biofilms; Candida albicans; Germ tube formation; Microorganisms; PHARMACOLOGY & PHARMACY; Pharmacy; Physiology; Staphylococcus infections; Sternbergia spp; Virulence; Virulence factor; United States > US; Turkey; Candida albicans; Antifungal activity; Biofilm inhibition; Virulence factor; Germ tube formation; Sternbergia spp
• ISSN: 2175-9790; 1984-8250; 2175-9790
• DOI: 10.1590/s2175-97902019000117200

Natural products are rapidly becoming the primary sources of novel antimicrobial agents, as resistance to existing antimicrobial agents is increasing. Apart from determining the antimicrobial activity of natural products, it is also important to understand their effects on the virulence factors of microorganisms. This study aimed to determine the antimicrobial activity of Sternbergia species prevalent in Turkey and investigate their role in the inhibition of germination tube and biofilm formation, both of which are known to be important virulence factors of Candida albicans. The antimicrobial activities of the plant extracts were evaluated using bore-plate and broth microdilution method. The extracts’ capacity to inhibit the formation of the germ-tube was also evaluated. The findings of our study revealed that Sternbergia lutea, Sternbergia vernalis possessed antimicrobial activities, with MIC values ranging between 0.048 mg/mL and 0.39 mg/mL. The highest antimicrobial activity was observed against Candida dubliniensis (0.048 mg/mL). While evaluating the inhibition of fungal germination activities, S. vernalis extract (at a concentration of 0.09 mg/mL) was found to be the most effective against C. albicans ATCC 90028 strain. The results also indicated that S. vernalis extracts at sub-MIC levels inhibited germ tube formation and modulated the tail-length of germinated cells, both of which are important virulence factors of C. albicans. Furthermore, the inhibition of biofilm-formation was also investigated, and it was found that two Sternbergia spp. extracts at or below MIC levels inhibited biofilm formation.