December 5th, 2016

Testing performed at Rutgers University in Amy Howell’s laboratory

Samples were tested for in vitro bacterial anti-adhesion activity (AAA) on a per weight basis. Samples were suspended (60 mg/ml) in PBS, neutralized with 1 N NaOH, diluted serially (2-fold), and tested for bacterial anti-adhesion activity utilizing an HRBC hemagglutination assay specific for uropathogenic P-fimbriated E. coli according to Foo et al. (Phytochemistry, 2000).  The concentration at which hemagglutination activity was suppressed by 50% was recorded as the endpoint for the assay and was considered the minimum inhibitory concentration (MIC).  The lower the MIC, the higher the anti-adhesion activity (AAA) of the sample.    Anti-adhesion assays were repeated three times and the results averaged. The standard deviation for the assay is +/- one dilution on each side of the MIC.  Anti-adhesion assays were repeated three times and the results averaged. Controls included wells containing bacteria + PBS, HRBC + PBS, bacteria + test compound, HRBC + test compound, and bacteria + HRBC.


Sample Product Lot # AAA Whole Product (mg/mL)
1. Organic Cranberry Juice Powder/ Acacia A 16-193  30
2. Organic Cranberry Juice Powder/ Acacia B 16-205  30-60
3. Cranberry Seed Powder 10N72020 15-276 Not detected


The final concentration at which anti-adhesion activity could be detected was recorded above.  The smaller the AAA number, the greater the activity. The result for sample 2 was similar to samples 1, as it was within the standard deviation for the assay.  These results indicate anti-adhesion activity.  Anti-adhesion activity was not able to be detected in sample 3, as the sample was insoluble in aqueous solutions used in the testing methodologies.  It is unknown whether these insoluble materials have anti-adhesion activity, as there is no known testing method that will measure this, as all current testing methods rely on polar solvents (water, PBS, etc.) because non polar solvents will damage bacterial cell membranes.



Amy Howell, Ph.D.

Research Scientist, Rutgers University



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