title: Pomegranate ellagitannins stimulate growth of gut bacteria in vitro: Implications for prebiotic and metabolic effects.
abstract: The present study investigated the effect of pomegranate extract (POMx) and pomegranate juice (POM juice) on the growth of major groups of intestinal bacteria: Enterobacteriaceae, Bacteroides fragilis group, clostridia, bifidobacteria, and lactobacilli, and the utilization of pomegranate polyphenols by Bifidobacterium and Lactobacillus. The total phenolic content of the pomegranate extract and juice was determined using the Folin-Ciocalteau colorimetric method and reported as gallic acid equivalent (GAE). The polyphenol composition was determined by HPLC. Stool specimens were incubated with 400, 100, and 25 μg/ml GAE POMx and POM juice and subjected to selective culture. Bifidobacterium and Lactobacillus strains were incubated with 400 μg/ml GAE POMx and POM juice and metabolites were analyzed. POMx and POM juice increased the mean counts of Bifidobacterium and Lactobacillus and significantly inhibited the growth of B. fragilis group, clostridia, and Enterobacteriaceae in a dose-response manner. Bifidobacterium and Lactobacillus utilized ellagic acid and glycosyl ellagic acid but little or no punicalin was utilized. Neither POMx nor POM juice was converted to urolithins by the test bacteria or the in vitro stool cultures. The effect of pomegranate on the gut bacteria considered to be beneficial (Bifidobacterium and Lactobacillus) suggests that pomegranate may potentially work as a prebiotic. The concept that polyphenols such as those in pomegranate impact gut microbiota populations may establish a new role for polyphenols in human health.
authors.affiliation: Department of Medicine, VA Medical Center West Los Angeles, 11301 Wilshire Blvd., Los Angeles, CA 90073, USA; Department of Research Service, VA Medical Center West Los Angeles, 11301 Wilshire Blvd., Los Angeles, CA 90073, USA; Department of Medicine, UCLA School of Medicine, 405 Hilgard Ave., Los Angeles, CA 90095, USA; UCLA Center for Human Nutrition, UCLA School of Medicine, 405 Hilgard Ave., Los Angeles, CA 90095, USA. Electronic address: ZLi@mednet.ucla.edu.
authors.forename: Zhaoping
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Research Service, VA Medical Center West Los Angeles, 11301 Wilshire Blvd., Los Angeles, CA 90073, USA.
authors.forename: Paula H
authors.initials: PH
authors.lastname: Summanen
authors.affiliation: Department of Research Service, VA Medical Center West Los Angeles, 11301 Wilshire Blvd., Los Angeles, CA 90073, USA; Department of Sustainable Engineering, College of Industrial Technology, Nihon University, Japan.
authors.forename: Tomoe
authors.initials: T
authors.lastname: Komoriya
authors.affiliation: UCLA Center for Human Nutrition, UCLA School of Medicine, 405 Hilgard Ave., Los Angeles, CA 90095, USA.
authors.forename: Susanne M
authors.initials: SM
authors.lastname: Henning
authors.affiliation: UCLA Center for Human Nutrition, UCLA School of Medicine, 405 Hilgard Ave., Los Angeles, CA 90095, USA.
authors.forename: Ru-Po
authors.initials: RP
authors.lastname: Lee
authors.affiliation: UCLA Center for Human Nutrition, UCLA School of Medicine, 405 Hilgard Ave., Los Angeles, CA 90095, USA.
authors.forename: Eliisa
authors.initials: E
authors.lastname: Carlson
authors.affiliation: UCLA Center for Human Nutrition, UCLA School of Medicine, 405 Hilgard Ave., Los Angeles, CA 90095, USA.
authors.forename: David
authors.initials: D
authors.lastname: Heber
authors.affiliation: Department of Medicine, VA Medical Center West Los Angeles, 11301 Wilshire Blvd., Los Angeles, CA 90073, USA; Department of Research Service, VA Medical Center West Los Angeles, 11301 Wilshire Blvd., Los Angeles, CA 90073, USA; Department of Microbiology, Immunology and Molecular Genetics, UCLA School of Medicine, 405 Hilgard Ave., Los Angeles, CA 90095, USA; Department of Medicine, UCLA School of Medicine, 405 Hilgard Ave., Los Angeles, CA 90095, USA.
authors.forename: Sydney M
authors.initials: SM
authors.lastname: Finegold
mesh_terms: D001419:Bacteria / Q000187:drug effects* / Q000254:growth & development*; D058491:Bacterial Load; D041981:Gastrointestinal Tract / Q000382:microbiology*; D006801:Humans; D047348:Hydrolyzable Tannins / Q000302:isolation & purification / Q000378:metabolism*; D036341:Intercellular Signaling Peptides and Proteins / Q000302:isolation & purification / Q000378:metabolism*; D029561:Lythraceae / Q000737:chemistry*; D010636:Phenols / Q000302:isolation & purification / Q000378:metabolism; D056692:Prebiotics
chemical_list: D047348:Hydrolyzable Tannins; D036341:Intercellular Signaling Peptides and Proteins; D010636:Phenols; D056692:Prebiotics
keywords: Bifidobacteria; Intestinal bacteria; Lactobacilli; Pomegranate; Pomegranate extract; Pomegranate juice; Prebiotic