Inactivation of Enterobacter sakazakii by water-soluble muscadine seed extracts

Int J Food Microbiol. 2009 Feb 28;129(3):295-9. doi: 10.1016/j.ijfoodmicro.2008.12.014. Epub 2008 Dec 24.

Abstract

Hot and cold water-soluble muscadine (Vitis rotundifolia) seed extracts and their polar and polyphenol fractions from two Muscadine cultivars ('Ison', purple and 'Carlos', bronze) were investigated for their inhibition of Enterobacter sakazakii. The heat treatment on each seed extract not only increased total phenolics and tannic acid but also enhanced antimicrobial activity against two strains of E. sakazakii. Within 1 h, all seed extracts reduced an initial population (approximately 6 log CFU/mL) of E. sakazakii to a non-detectable level (minimum detection limit, 10 CFU/mL). Regardless of extraction method and cultivar, only the polar fractions which contained malic, tartaric and tannic acids showed antimicrobial activity against two strains of E. sakazakii. The polyphenol fractions which contained gallic acid, catechin, epicatechin, ellagic acid and pigments showed slight inhibition against E. sakazakii. Results showed that water-soluble muscadine seed extracts (pH 3.3-3.78) contained strong antimicrobial inhibitors against E. sakazakii while acidified peptone water (pH 3.3) did not show any antimicrobial activity.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology*
  • Chromatography, High Pressure Liquid
  • Cronobacter sakazakii / drug effects*
  • Hydrogen-Ion Concentration
  • Hydroxybenzoates / chemistry
  • Phenols / chemistry
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology*
  • Seeds / chemistry*
  • Vitis / chemistry*
  • Water / chemistry*

Substances

  • Anti-Bacterial Agents
  • Hydroxybenzoates
  • Phenols
  • Plant Extracts
  • Water
  • phenolic acid