Studies Regarding the Antimicrobial Behavior of Clotrimazole and Limonene

Topical antimicrobial formulations using medicinal plant-derived essential oils targeting methicillin resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) causes a variety of healthcare-associated and community-acquired infections. Due to limited availability of effective antimicrobials for treating MRSA infections, there is a growing need to explore alternative therapeutic approaches. Here, the antimicrobial activities of 19 oils, popularly used for their medicinal properties, were tested against MRSA USA300. Oils obtained from cinnamon, clove, tangerine, and coriander showed the most promising activities, demonstrating bactericidal, anti-adhesive and anti-biofilm activities, and synergistic properties with common antibiotics. Given that clove and cinnamon oils showed the best activities, they were incorporated into topical formulations. Not only did the formulations with oils maintain antimicrobial and anti-adhesive activities, but their anti-biofilm property was potentiated. Tests on Galleria mellonella larvae suggested that the formulation is non-toxic. The formulations proposed here are a great alternative for the decolonisation of surfaces containing MRSA and can help circumventing antimicrobial resistance, a growing threat in the hospital environment.

Anti-Proliferative Potential of Cynaroside and Orientin-In Silico (DYRK2) and In Vitro (U87 and Caco-2) Studies

Luteolin derivates are plant compounds with multiple benefits for human health. Stability to heat and acid hydrolysis and high resistance to (auto)oxidation are other arguments for the laden interest in luteolin derivates today. The present study was designed to compare the in silico and in vitro anti-proliferative potential of two luteolin derivates, luteolin-7-O-glucoside/cynaroside (7-Lut) and luteolin-8-C-glucoside/orientin (8-Lut). In silico investigations were carried out on the molecular target, namely, the human dual specificity tyrosine phosphorylation-regulated kinase 2 (DYRK2) in association with its natural ligand, curcumin (PDB ID: 5ZTN), by CLC Drug Discovery Workbench v. 1.5.1. software and Molegro Virtual Docker (MVD) v. MVD 2019.7.0. software. In vitro studies were performed on two human tumor cell lines, glioblastoma (U87) and colon carcinoma (Caco-2), respectively. Altogether, docking studies have revealed 7-Lut and 8-Lut as effective inhibitors of DYRK2, even stronger than the native ligand curcumin; in vitro studies indicated the ability of both luteolin glucosides to inhibit the viability of both human tumor cell lines, up to 85% at 50 and 100 µg/mL, respectively; the most augmented cytotoxic and anti-proliferative effects were obtained for U87 exposed to 7-Lut (IC50 = 26.34 µg/mL). The results support further studies on cynaroside and orientin to create drug formulas targeting glioblastoma and colon carcinoma in humans.

Antioxidant and Antibacterial Activity of Plant Extracts

Medicinal plants have been a very important source of medicinal products for millennia [...].

Potential Benefits of Dietary Plant Compounds on Normal and Tumor Brain Cells in Humans: In Silico and In Vitro Approaches

Neuroblastoma can be accessed with compounds of larger sizes and wider polarities, which do not usually cross the blood-brain barrier. Clinical data indicate cases of spontaneous regression of neuroblastoma, suggesting a reversible point in the course of cell brain tumorigenesis. Dual specificity tyrosine-phosphorylation-regulated kinase2 (DYRK2) is a major molecular target in tumorigenesis, while curcumin was revealed to be a strong inhibitor of DYRK2 (PBD ID: 5ZTN). Methods: in silico studies by CLC Drug Discovery Workbench (CLC) and Molegro Virtual Docker (MVD) Software on 20 vegetal compounds from the human diet tested on 5ZTN against the native ligand curcumin, in comparison with anemonin. In vitro studies were conducted on two ethanolic extracts from Anemone nemorosa tested on normal and tumor human brain cell lines NHA and U87, compared with four phenolic acids (caffeic, ferulic, gentisic, and para-aminobenzoic/PABA). Conclusions: in silico studies revealed five dietary compounds (verbascoside, lariciresinol, pinoresinol, medioresinol, matairesinol) acting as stronger inhibitors of 5ZTN compared to the native ligand curcumin. In vitro studies indicated that caffeic acid has certain anti-proliferative effects on U87 and small benefits on NHA viability. A. nemorosa extracts indicated potential benefits on NHA viability, and likely dangerous effects on U87.