Probiotic Formulation in Vitro Effect on Phenol and p-Cresol Levels

J. Marczely, BS1, R. Dheer, BA1, P. Ranganathan, MS1, B. Patel, PhD1, N. Ranganathan, PhD1 and E. A. Friedman, MD2.
1Kibow Biotech Inc., Phila., PA, United States and 2Dept. of Med., Downstate Medical Center, Brooklyn, NY, United States. Journal of the American Society of Nephrology 15: Oct 2004 pp. 112A F-PO212

Serum phenol and p-cresol levels increase in kidney failure and are thought to contribute to the uremic syndrome. Typical values in plasma levels obtained form uremic patients are (normal v. uremic phenol levels 0.6±0.2mg/L v. 2.7±3.9mg/L; p-cresol 0.6±1.0mg/L v. 20.1±10.3mg/L). It is known that some intestinal bacteria metabolize tyrosine into phenol and/or p-cresol. Previously, we reported that feeding 5/6 nephrectomized rats a probiotic formulation reduced concentrations of several uremic solutes and extended their life.

We now report the effects of a new bacterial mixture on phenol and p-cresol levels in artificial intestinal fluid (AIF) containing added uremic solutes including 2.7mg/L Phenol and 20mg/L p-Cresol. Run in triplicate, nine (9) 100 ml test systems incubated @ 37C with following additives in each separate container: (St -Streptococcus thermophilus KB06, La -Lactobacillus acidophilus KB20, Bl -Bifidobacterium longum KB71). 1)100mg St+10 mg La+10mg Bl. 2)100mg St. 3)10mg La. 4)10mg Bl. 5)100mg St+10mg La. 6)100mg St+10mg Bl. 7)10mg La+10mg Bl. 8-9)controls. 24 hr aliquots assayed for phenol and p-cresol. HPLC: Beckman 125 Solvent Module. Detect: Jasco FP-2020. Mobile: water/ACN (70/30) 1 ml/min. Col: Luna C18, 4.6x150mm, 5µm. ?: EX 260nm EM 305nm. Record 0-15 min. Verses the control, a combination of 10:1 St to La worked best to reduce phenol levels over 24 hrs (6.0%±3.0). When Bl was added this reduction decreased to 3.0%±3.0. A combination of 10:1 St to La worked best to reduce p-cresol levels (14.0%±3.0). When Bl was added this reduction decreased to 9.0%±3.0. While the observed reductions in nitrogenous solute concentration are modest, prior reports found that intestinal bacteria actually increased these levels. The decreased concentrations of nitrogenous solutes noted in our in vitro system amplify previous identification of bacterial strains that reduce urea, creatinine, and several amines in-vivo. Kibow’s proprietary formulation of St, La and Bl reduce phenol and p-cresol levels by 3.0%±3.0 and 9.0%±3.0 respectively may evolve into adjunctive therapy in chronic renal failure.