Potential of incorporating Alpinia malaccensis crude extract into hand sanitizers

The commercial hand sanitizers are made from alcohol which might not have residual antibacterial activity because alcohol is highly volatile. This study was performed to determine the efficacy of hand sanitizer incorporated with Alpinia malaccensis crude extract. Different concentrations (5 mg/ml, 10 mg/ml and 50mg/ml) of A. malaccensis containing hand sanitizers were compared with that of World Health Organization (WHO) formulation and recommended commerciallyavailable hand sanitizers. Disk diffusion assay and synergistic antimicrobial activity test were used as in vitro methods to evaluate antimicrobial inhibition. Finger imprint method was conducted as in vivo method to evaluate the efficacy of hand sanitizer on resident microflora for 0, 2, 5, 10, and 15 minutes. Disk diffusion assay was tested against Staphylococcus aureus 113, Escherichia coli, Listeria monocytogenes and Salmonella enterica Typhimurium. The commercial sanitizer (T4) showed a significantly (p˂0.05) smaller diameter inhibition zone 14.33±0.58 mm for S. aureus compared to other treatments, namely 5 mg/ml (T1), 10 mg/ml (T2) of A. malaccensis containing sanitizers and WHO formula (T3). There is a possibility to add A. malaccensis crude extract to enhance the efficacy of the commercial sanitizer. A significant synergistic antimicrobial inhibition 7.99±0.02 cfu/ml was recorded in 50 mg/ml+55% alcohol hand sanitizer (T2) compared to the control (T4). The finger imprint method did not show any significant differential reduction within the tested time. Alcohol-based hand sanitizers incorporated with herbal A. malaccensis could be used to enhance the efficacy of the available commercial sanitizers.