Antimicrobial activity of the essential oil of Cymbopogon citratus (DC) Stapf. on Staphylococcus spp., Streptococcus mutans and Candida spp.

Medicinal plants with fungicide action, antibacterial and anti-inflammatory effects are under investigation. The main purpose of this work was to evaluate the antimicrobial activity of the essential oil from Cymbopogon citratus (DC) Stapf. on strains of Staphylococcus spp., Streptococcus mutans and Candida spp. with planktonic and biofilm growth. To study the micro-organisms in planktonic cells, the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were determined by using 9 clinical strains for each species and 1 ATCC (American Type Culture Collection) from C. albicans, C. tropicalis, C. glabrata, S. aureus, S. epidermidis and S. mutans. In order to evaluate the effects of the essential oils on biofilms, strains of S. aureus (ATCC 6538), S. mutans (ATCC 35688) and C. albicans (ATCC 18804) were used. The biofilm was formed on acrylic resin discs with isolated micro-organisms or in associations. The number of colony-forming-units (CFU) obtained in each biofilm (CFU/ml) was submitted to Student's t statistical test. The results demonstrated that the essential oil of Cymbopogon citratus showed microbiostatic and microbicidal activity against all tested strains. The average CFU/ml for the biofilm of S. aureus, S. mutans and C. albicans, whether isolated or in association, was lower in the group treated with essential oil than in the control group

Oral cytology in cannabis smokers.

The effects of cannabis/methaqualone/tobacco smoking on the epithelial cells of the tongue, buccal mucosa and floor of the mouth were examined. Oral mucosal smears for detection of cellular changes were taken from 4 sites in 16 patients. The tongue blade scraping technique was used. The sites sampled included the buccal mucosa (left and right sides), the posterior dorsum of the tongue and the anterior floor of the mouth. Tobacco smoking and non-smoking controls were also examined. The only significant difference between cannabis users and controls was the greater prevalence of bacterial cells in the smears taken from cannabis users. However, there were also greater numbers of degenerate and atypical squamous cells in cannabis smokers than in cigarette-smoking and non-smoking controls. Epithelial cells in smears taken from cannabis users and tobacco-smoking controls also showed koilocytic changes, which were not seen in smears taken from non-smoking controls. Koilocytosis is indicative of human papilloma virus infection, although no apparent lesions were seen in the patients from whom smears had been taken. It would appear that there is a greater tendency towards damaged and immature surface epithelial cells in cannabis smokers.Articl