Comprehensive evaluation of physico-chemical, antioxidant, and antimicrobial properties in commercial soaps: A study on bar soaps and liquid hand wash
Jannatul Ferdous Nova, Susmita Zaman Smrity, Md. Mahadi Hasan, Md. Tariquzzaman, Md Al Amin Hossain, Md. Tanvirul Islam, Md. Rashedul Islam, Selina Akter, Md. Sifat Rahi, Md. Tuhinur R. Joy, Zannatul Kowser
Abstract
Soap is essentially used for various purposes. Therefore, it is important to determine the physico-chemical, antioxidant, and antimicrobial properties of soaps to evaluate their quality. The present research works on 22 commercial soaps which include bar soaps (SN 1-SN 19) and liquid hand wash (SN 20-SN 22). The values of different parameters for commercial soaps are observed which are between 3.84% – 83.75% for moisture content, 6.83 cm – 25.16 cm for foam height, 7.01-10.17 for pH, 62.47% – 91.39% for total fatty matter, 0.20 % - 1.17% for total alkali content, zone of inhibition 17.33 mm/100%conc. – 29.27mm/100% conc., antioxidant activity 357.4117μg/ml – 777.1546 μg/ml. It is observed that all of the soaps have a foam height, and pH within the permitted limit (FH-above 1.5 cm, pH 7-10). All bar soap has a total fatty matter and a total alkali content within the accepted value. Moreover, 8 soaps show antimicrobial properties against Staphylococcus aureus, which were further tested for rapid efficacy and antioxidant properties. A survey report of 22 commercial branded soaps was done on 50 people in Bangladesh to get feedback from customers. Combining all the parameters, SN 3 has good results among bar soaps with mild moisturizing and cleansing properties (MC-8.30±0.035%, FH-22.33±0.29 cm), is safe for the skin (pH-9.83±0.02, TAC-0.99±0.03), has good TFM values (72.89%), has proficient bacteria growth-inhibiting properties (ZI-18.67±0.29 mm/100 % conc.) and has the ability to remove free radicals (357.41±2.07μg/ml). Besides, SN-21 among liquid hand wash soaps possesses overall excellence as it moisturizes skin well (MC-83.75±0.05%), is almost safe for skin (pH-7.73±0.02, TAC-0.98±0.01%), has TFM (11.3516%), has good cleansing capacity (FH-22.66±0.58 cm) and bacteria growth inhibiting activity (29.27±0.25 mm/199 % conc.), destroys selected bacteria (MIC – 1.2×10 7 CFU at 1 minute and 5.5×10 7 CFU at 10 seconds), and wash away free radicals from skin (420.64±3.62μg/ml).