Deodorant effects of a sage extract stick: Antibacterial activity and sensory evaluation of axillary deodorancy

Deodorant products prevent the growth and activity of the degrading apocrine gland bacteria living in the armpit. Common antibacterial agents in the market like triclosan and aluminum salts, in spite of their suitable antibacterial eff ects, increase the risk of Alzheimer’s disease, breast and prostate cancers or induce contact dermatitis. Th erefore, plant extracts possessing antibacterial eff ects are of interest. Th e aim of the present study was to verify the in vitro antimicrobial eff ects of diff erent sage extracts against two major bacteria responsible for axillary odor, and to evaluate the deodorant eff ect of a silicon-based stick containing sage extracts in diff erent densities in humans. Diff erent fractions of methanolic extract of Salvia offi cinalis (sage) were evaluated on a culture of armpit skin surface of volunteers through agar microdilution antimicrobial assay. Th en, randomized, doubleblind placebo-controlled clinical trial with the best antibacterial fraction was conducted on 45 female healthy volunteers. Participants were treated with a single dose in four groups, each containing 15 individuals: Group 1 200 g/mL), 2 (400 g/mL), 3 (600 g/ mL) of dichloromethane sage extract, and placebo (without extract). A standard sensory evaluation method for the evaluation of deodorant effi cacy was used before, and two hours, four hours, and eight hours after single application of a deodorant or placebo (ASTM method E 1207-87 Standard Practice for the Sensory Evaluation of AxillaryDeodorancy). Th e data were analyzed with two factors relating to densities and time. In 45 participants with a mean [± standard deviation (SD)] age of 61.5±11.8 years, statistically signifi cant within-group diff erences were observed before and two, four, and eight hours after deodorant treatment for groups 1, 2, and 3. Groups 1, 2, and 3 had a signifi cantly smaller odor score than placebo after two, four, and eight hours (P < 0.001). In a comparison of diff erent deodorant densities, the interaction eff ect was not signifi cant between deodorant 200 and 400 g/mL, but was signifi cant between 200 and 600 and between 400 and 600 g/mL sage extract sticks (P < 0.001). Before running the sensory evaluation of the deodorant sticks on the subjects, a rabbit skin patch test was used to demonstrate that the formulation had no irritants. A single treatment with a stick deodorant containing dichloromethane sage extract of 200, 400, or 600 g/mL concentrations was eff ective in reducing the axillary malodor level compared with the control, in healthy subjects.