Chemical and biological study of Plumbago europaea: Development of a new alcohol-free mouthwash against oral candidiasis

Abstract

In the field of pharmaceutical science, the main objective of the most current research on natural plant extracts and their use in medicine is to develop and introduce scientifically acceptable agents that can replace antimicrobial drugs in the treatment of infectious diseases. The present work aims to investigate new antimicrobial agents from the roots of Plumbago europaea, a medicinal plant native to the Tlemcen region, as well as to develop an application of these plant extracts in a pharmaceutical formulation. The essential oil and hydrolate extract obtained from the roots of Plumbago europaea were analyzed by GC/MS and plumbagin was the majority compound. Both the essential oil and hydrolate extract showed moderate free radical scavenging and reducing ability with IC50s of 2.72 and 2.98 mg/ml, respectively. The antimicrobial screening results revealed that the hydrolat extract was more active than the essential oil against all tested microorganisms with interesting MIC values (19 μg/mL). The in-vitro efficacy of the combination of the hydrolat extract with amphotericin B produced a synergy against Candida albicans (IP444) The ethanolic extract of Plumbago europaea roots was subjected to silica gel column chromatography for purification of active compound. Three main fractions were collected and named F1, F2 and F3. The crude extract and the purified fractions show very interesting antioxidant and antifungal properties. The hemolytic and anti-inflammatory power of the ethanolic extract was evaluated in vitro and the results obtained showed a weak hemolytic effect and a good anti-inflammatory activity. An alcohol-free mouthwash containing different concentrations of the ethanolic extract as active ingredient was prepared and evaluated for its physicochemical properties, stability and in vitro antifungal efficacy. The prepared alcohol-free mouthwash was effective in inhibiting the growth of Candida albicans yeast in vitro, thus demonstrating the efficacy and potential usefulness of the ethanolic extract of Plumbago europaea in the control of candidiasis. The results of the stability study show that the product will maintain its basic activity and integrity for a long period of time.