Rhamnolipids Nano-Micelles as a Potential Hand Sanitizer

Abstract

COVID-19 is a pandemic disease caused by the SARS-CoV-2, which continues to cause global health and economic problems since emerging in China in late 2019. Until now, there are no standard antiviral treatments. Thus, several strategies were adopted to minimize virus transmission, such as social distancing, face covering protection and hand hygiene. Rhamnolipids are glycolipids produced formally by Pseudomonas aeruginosa and as biosurfactants, they were shown to have broad antimicrobial activity. In this study, we investigated the antimicrobial activity of rhamnolipids against selected multidrug resistant bacteria and SARS-CoV-2. Rhamnolipids were produced by growing Pseudomonas aeruginosa strain LeS3 in a new medium formulated from chicken carcass soup. The isolated rhamnolipids were characterized for their molecular composition, formulated into nano-micelles, and the antibacterial activity of the nano-micelles was demonstrated in vitro against both Gram-negative and Gram-positive drug resistant bacteria. In silico studies docking rhamnolipids to structural and non-structural proteins of SARS-CoV-2 was also performed. We demonstrated the efficient and specific interaction of rhamnolipids with the active sites of these proteins. Additionally, the computational studies suggested that rhamnolipids have membrane permeability activity. Thus, the obtained results indicate that SARS-CoV-2 could be another target of rhamnolipids and could find utility in the fight against COVID-19, a future perspective to be considered.

Evaluation of the Antimicrobial Efficacy of N-Acetyl-l-Cysteine, Rhamnolipids, and Usnic Acid—Novel Approaches to Fight Food-Borne Pathogens

“…In this work, three types of natural substances (NAC, RLs, and UA) were tested for their ability to inhibit bacterial growth, prevent biofilm formation, and reduce biofilm mass of four selected bacterial food-borne pathogens (Gram-positive L. monocytogenes, S. aureus, and Gram-negative E. coli, S. enterica Infantis, and Enteritidis). Information regarding the antimicrobial efficacy of NAC, RLs, and UA against food-borne pathogens is sparse; however, all the substances previously showed promising antimicrobial efficacy against other pathogens [15][16][17][18][19][22][23][24][25][26][27][28][29][30][31][32][33].…”

“…coli , S. enterica Infantis, and Enteritidis). Information regarding the antimicrobial efficacy of NAC, RLs, and UA against food-borne pathogens is sparse; however, all the substances previously showed promising antimicrobial efficacy against other pathogens [ 15 , 16 , 17 , 18 , 19 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ].…”

“…This strongly suggests that additional, potentially less conventional approaches are needed to control biofilm formation in food industry settings. One possible strategy is to employ natural substances, such as N -Acetyl -l- cysteine (NAC), rhamnolipids (RLs; R90), and (+)-usnic acid (UA), all of which previously showed promising antimicrobial efficacy against important clinical pathogens [ 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ]. Other benefits of these substances are their solubility, affordability, and chemical stability.…”

“…They have been utilized in a wide range of applications, including medicine (anticancer and antibiofilm agents), cosmetics (cosmetic formulations), the food industry (additives and antimicrobial agents), biofuels, and in bioremediation of pesticides and heavy metals [ 24 , 25 , 26 , 27 ]. Although the mechanism of action is not completely understood, it is supposed that RLs may disturb membrane structure through interactions with phospholipids and membrane proteins [ 23 , 28 ]. RLs selected for this study are declared as non-toxic.…”

“…However, the cytotoxic effect may be changed by alteration of RLs chemical structures [ 24 ]. Regarding the antimicrobial effect of RLs on planktonic cells and biofilms, RLs can reduce cell adhesion, affect biofilm maturation, and disrupt mature biofilms, especially of Gram-positive bacteria [ 24 , 25 , 28 ]. However, the anti-biofilm activity has been tested only against methicillin-resistant S. aureus and L. monocytogenes [ 24 , 25 ].…”