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ARS Home » Pacific West Area » Albany, California » Western Regional Research Center » Foodborne Toxin Detection and Prevention Research » Research » Publications at this Location » Publication #374454

Research Project: Advance the Development of Technologies for Detecting and Determining the Stability and Bioavailability of Toxins that Impact Food Safety and Food Defense

Location: Foodborne Toxin Detection and Prevention Research

Title: whISOBAXTM inhibits bacterial pathogenesis and enhances the effect of antibiotics

item Rasooly, Reuven
item CHOI, HWANG-YONG - Framingham State College
item Do, Paula
item MORRONI, GIANLUCA - Polytechnic University Of Marche
item BRESCINI, LUCIA - Polytechnic University Of Marche
item CIRONI, OSCAR - Polytechnic University Of Marche
item GIACOMETTI, ANDREA - Polytechnic University Of Marche
item APOSTOLIDIS, EMMANOUIL - Polytechnic University Of Marche

Submitted to: Antibiotics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/11/2020
Publication Date: 5/19/2020
Citation: Rasooly, R., Choi, H., Do, P.M., Morroni, G., Brescini, L., Cironi, O., Giacometti, A., Apostolidis, E. 2020. whISOBAXTM inhibits bacterial pathogenesis and enhances the effect of antibiotics. Antibiotics. 9(5):264.

Interpretive Summary: whISOBAX (WH) is a witch hazel extract that contains a high level of phenolic compounds that have anti microbial properties. Both gram positive and gram-negative bacteria are sensitive to WH, including those that are notoriously resistant to antibiotic treatment, like MRSA. Additionally, WH enhances the effect of commonly used antibiotics while preventing bacterial pathogenesis, thus enabling eradication of infection while reducing the need of excessive antibiotic use.

Technical Abstract: As bacteria are becoming more resistant to commonly used antibiotics, alternative therapies are being sought. whISOBAX (WH) is a witch hazel extract that is highly stable (tested up to 2 months in 37oC) and contains a high phenolic content, where 75% of it is hamamelitannin and traces of gallic acid. Phenolic compounds like Gallic Acid are known to inhibit bacterial growth, while hamamelitannin is known to inhibit staphylococcal pathogenesis (biofilm formation and toxin production). WH was tested in vitro for its antibacterial activity against clinically relevant gram-positive and gram-negative bacteria, and its synergy with antibiotics determined using checkerboard assays followed by isobologram analysis. WH was also tested for its ability to suppress staphylococcal pathogenesis, which is the cause of a myriad of resistant infections. Here we show that WH inhibits the growth of all bacteria tested, with variable efficacy levels. The most WH-sensitive bacteria tested were Staphylococcus epidermidis, Staphylococcus aureus, Enterococcus faecium and Enterococcus faecalis, followed by Acinetobacter baumannii, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Streptococcus agalactiae and Streptococcus pneumoniae. Furthermore, WH was shown on S. aureus to be synergistic to Linezolid and Chloramphenicol and cumulative to Vancomycin and Amikacin. The effect of WH was tested on staphylococcal pathogenesis and shown here to inhibit biofilm formation (tested on S. epidermidis) and toxin production (tested on S. aureus Enterotoxin A (SEA). Toxin inhibition was also evident in the presence of subinhibitory concentrations of Ciprofloxacin that induces pathogenesis. Put together, our study indicates that WH is very effective in inhibiting the growth of multiple types of bacteria, is synergistic to antibiotics, and is also effective against staphylococcal pathogenesis, often the cause of persistent infections. Our study thus suggests the benefits of using WH to combat various types of bacterial infections, especially those that involve resistant persistent bacterial pathogens.