Development of Foot Scrub Ball from Piper betle L. Leaf Extract

Abstract

Introduction and objective: The problem of foot odor has disturbed the personality and affects the self-confidence of the sufferers. At present, a rather few natural products have been used to suppress foot odor. The aim of this study was to investigate the antibacterial activity of the extract of Piper betle L. leaves (betel or bai phlu in Thai) against Staphylococcus epidermidis, to develop a betel extract scrub ball (exfoliating sphere) against foot odor, and to assess the scrub ball users’ satisfaction.

Method: Antibacterial activity was tested by disc diffusion method and broth microdilution. Then, the antibacterial concentration of betel leaf extract was used to develop a scrub ball formula. After biological stability testing, the product was trialed in 40 volunteers selected through purposive sampling. A satisfaction assessment form was used for data collection; and statistics used for data analysis included frequency, percentage, mean and standard deviation.

Results: The betel leaf extract showed no zone of inhibition by the disc diffusion method. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were 375 and 1,500 µg/mL, respectively, by broth microdilution method, and this concentration was added to the product. Formula 2 luffa scrub consisting of transparent glycerol soap base, polyethylene glycol, coconut oil, sodium lauryl sulfate, glydant, and acetic acid was the most stable at day 30 and showed an inhibition zone of 6.88 ± 0.26 mm. As a result, the overall satisfaction with the product by the study group was high ( = 4.32±0.54).

Discussion: The Piper betle L. leaf extract contains phenol groups such as eugenol and chavicol. The extract was used at a concentration of 1,500 µg/mL as it was the lowest level capable of inhibiting bacterial growth. Additional ingredients in the scrub ball including glydant and polyethylene glycol contributed to enhancing the antimicrobial effect and maintaining stability against microbial contamination. The formula containing 26.25% transparent glycerin soap base is physically stable and exhibits germ-inhibiting effects when stored at room temperature for 30 days. The overall satisfaction with the pattern of usage was at a high level.

Conclusion: The scrub ball made from the extract of Piper betle L. leaves could be used alternatively as a natural product to reduce foot odor. This effort helps enhance the use and value of local herbs and the information can be a guide for further commercial development of the herb.