Antimicrobial activity of Camellia sinensis (green tea) and Cynara scolymus (artichoke) glycolic extracts

• Grant number: 15/07167-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2015
• End date: May 31, 2016
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Luciane Dias de Oliveira
• Grantee: Letícia de Oliveira
• Host Institution: Instituto de Ciência e Tecnologia (ICT). Universidade Estadual Paulista (UNESP). Campus de São José dos Campos. São José dos Campos , SP, Brazil

Abstract

The use of herbal medicines in dentistry is still very restricted, being of great importance to expand scientific research about plant extracts on microorganisms of dental interest, aiming to direct their therapeutic use, including irrigation and intracanal medications, mouthwashes, toothpastes, ointments, among others. The aim of this study was to determine the in vitro antimicrobial activity of Camellia sinensis (green tea) and Cynara scolymus (artichoke) extracts on planktonic culture and monotypic biofilms of Candida albicans, Staphylococcus aureus, Enterococcus faecalis, Streptococcus mutans and Pseudomonas aeruginosa. Microdilution broth method was used for the planktonic form, according to the Clinical and Laboratory Standards Institute (CLSI), in order to determine the minimum inhibitory concentrations (MIC) and minimal microbicidal (MMC). For biofilms, standardized suspensions of 107 cells/mL were added to microtiter plate wells and after 48 h of incubation (37°C) under agitation (75 rpm) were treated with green tea and artichoke extracts (contact time : 5 min and 24 h). Six groups (n=10) will be performed for each contact time: VER (green tea), ALC (artichoke), NIST (nystatin): antifungal control, CLOREX (control for bacteria), PROPIL (propylene glycol): extract solvent, CONT (saline): positive control. Then, biofilms will be disaggregated with ultrasonic homogenizer, the suspension will be diluted and plated on Sabouraud dextrose agar (yeast) or Brain Heart Infusion agar (bacteria). After 48 h, the colony forming units per milliliter (CFU/mL) will be counted and the values will be converted to log10. The results will be statistically analyzed by ANOVA and Tukey Test (p d 0.05).