Efficacy of Neem Leaves Extract and Aloe Vera as Antimicrobial in Hand Sanitizer

Abstract

Since the coronavirus disease pandemic of 2019 (COVID-19) is spreading quickly around the world, 99% alcohol-based hand sanitizer (ABHS) is utilized to minimize disease transmission. During the COVID-19 outbreak, isopropyl supply becomes limited. Herbal based hand sanitizers were used as an alternative way during pandemic to reduce the spreading of COVID-19. This study aimed to evaluate the efficacy of neem leaves extract and aloe vera as antimicrobials for Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) bacteria which can readily be found on the hands. Moreover, 30% isopropyl alcohol, citrus lemon oil, essential oil and vitamin E oil were also added in the formulations. Four different hand sanitizers were formulated which labelled as A1, A2, A3 and A4. The initial formulation, A1, is said to be the most effective because it contains the highest amount of neem leaf extract and aloe vera, and it is followed by A2, which contains less neem leaf extract and aloe vera. A3 does not contain neem leaf extract, while A4 does not contain aloe vera. All formulations contained the same amount of isopropyl alcohol, essential oil, vitamin E oil, and citrus lemon. Streaking methods on Tryptic Soy Agar plate and nutrient agar plate were used to evaluate the effectiveness of hand sanitizer against S. aureus and E. coli bacteria. The total colony forming unit (CFU) and percentage of effectiveness were calculated to compare the antimicrobial activity of all the formulations. The results revealed that a significant reduction in total bacterial colony counts of microbes after treatment with the formulations. Besides, pH value for A1, A2, A3 and A4 were also evaluated, and the results were 5.2, 5.3, 4.8, and 5.5 respectively. Among all four formulations, A1 showed the highest efficiency of microbial disinfectant for both S. aureus and E. coli bacteria by showing the reduction of microbes for 94.55% and 97.27% respectively since A1 contains the highest amount of neem leaves extract and aloe vera. It also has a skin-friendly pH value of 5.2 which is slightly acidic to control the bacterial infection and applicable since it is within the pH range of 4.5 to 6.5 found in human skin.