Synergistic and potential antifungal properties of tailored, one pot multicomponent monoterpenes co-delivered with fluconazole encapsulated nanostructure lipid carrier

Abstract

Abstract Frequent and variant infections are caused by the virtue of opportunistic fungi pathogens. Candidiasis, aspergillosis, and mucormycosis are pathogenic microorganisms that give rise to vast fungal diseases that alternate between moderate to fatal in severity. The use of fluconazole as an antifungal drug was limited due to the acquired resistance in some types of Candida and other fungal species. This study aims to consolidate fluconazole’s biological effectiveness against several pathogenic fungi. Six active monoterpenes (MTs) of carvacrol, linalool, geraniol, α-terpinene, citronellal, and nerolidol were selected and encapsulated in nanostructure lipid carrier (NLC) with (NLC-Flu-MTs) and/without (NLC-MTs) fluconazole in one nanoformulation to determine if they will act synergistically or not? The synthesized nanoformulation NLC-Flu-MTs and NLC-MTs exhibited very good particle size of 144.5 nm and 138.6 nm for size and zeta potential values of (− 23.5 mV) and (− 20.3 mV), respectively. Transmission electron microscope investigation confirmed that the synthesized NLCs have regular and spherical shape. The abundance and concentration of the six released monoterpenes were determined, as a novel approach, using GC–MS with very good results and validity. In-vitro antifungal screening was done before and after nano co-delivery against seven pathogenic, and aggressive fungi of Candida tropicalis, Candida krusei, Candida glabrata, Geotrichum Candidum, Candidaalbicans, Aspergillus Niger, and mucor circinelloides. Inhibition Zone diameter (IZD) and the minimum inhibitory concentration (MIC) were measured. Nanoformulations NLC-Flu-MTs and NLC-MTs manifested potential and unique biological susceptibility against all the tested microorganisms with reduced (MIC) values, especially against Candida Tropicalis (MIC = 0.97 µg/ml) which represents 16-fold of the value shown by NLC-MTs (MIC = 15.6 µg/ml) and 64-fold of fluconazole free before nanoformulation (MIC = 62.5 µg/ml). The efficiency of nanomaterials, particularly NLC-Flu-MTs, has become evident in the diminishing value of MIC which affirmed the synergism between fluconazole and the other six monoterpenes.