The use of Pistacia lentiscus L. in oral healthcare: chemical profile and biological activity

The undesirable side effects of antibiotics and antiseptics in addition to increasing microbial resistance have created a demand for new molecules as an alternative. With this intention, plants have become a hot topic in research. This in vitro study aimed to determine the fingerprint of Pistacia lentiscus L. (PLL) essential oil together with its potential antimicrobial capacity against different oral microorganisms and to evaluate a potential citotoxicity to human oral cells. Methods: PLL oil obtained from the leaves by hydro- distillation was chemically characterized by using GC/MS equipped with a fused silica capillary column (AT-5). As antimicrobial assays we used an agar diffusion test and Microbroth Dilution Technique (MIC) targeting against planktonic cells of Gram- positive (Streptococcus mutans, Lactobacillus acidophilus, Enterococcus faecalis), Gram-negative (Porphyromonas gingivalis, Fusobacterium nucleatum) and the yeast Candida albicans. Cell viability using periodontal ligament fibroblasts (PLF) and gingival fibroblasts (GF) was determined using WST-1 assay using PLL in a concentration range of 1 - 100 μg/ml for 72 hours. Results: Gas chromatography / Mass spectrometry demonstrated a very high representation of α-pinene and terpinen-4-ol (33%), which in addition to limonene (3,89%), α-myrcene (0,87%), α-caryophyllene (1.39%) and α-caryofhyllene (0.07%) allow us to classify the EO as pharmacological active compound. The disc diffusion assay and MICs demonstrated the antimicrobial potential of the terpenoids against planktonic cells of Gram-positive (Streptococcus mutans, Lactobacillus acidophilus, Enterococcus faecalis), Gram-negative (Porphyromonas gingivalis, Fusobacterium nucleatum) and the yeast Candida albicans with MICs ranging between 0.31 - 2.5 μg/ mL. Cell viability in human periodontal ligament fibroblasts and gingival fibroblasts using WST-1 assay and PLL in a concentration range of 1 - 100 μg/ml for 72 hours, showed no cytotoxicity up to the maximum concentration. Conclusions: these data mean PLL could be a new antimicrobial agent in oral health without side effect to human oral cells. Keywords Oral health care product, natural agents, oral diseases, resistance, periodontal bacteria, Candida albicans.