Koprololiitin

Koprololiitin is a term used in some scientific contexts to describe a class of metabolites linked to the gut microbial processing of ellagic acid and ellagitannins, often detected in fecal samples. The name incorporates the fecal origin implied by the copro- or kopro- prefix and reflects its association with intestinal metabolism. The term is not consistently used across the literature, and related compounds are sometimes referred to as coprolithins or as urolithin-related metabolites. There is no universally accepted chemical structure for koprololiitin, and reported compounds span a family of hydroxy- and methoxy-substituted polyphenolic derivatives with varying core architectures.

Formation occurs when gut bacteria metabolize ellagitannins obtained from foods such as pomegranates, berries, and nuts, ultimately yielding ellagic acid derivatives that may be transformed into koprololiitin-like structures. Koprololiitin has been reported in fecal matter and, in some cases, in urine following consumption of ellagitannin-rich diets. Individual differences in the gut microbiota influence whether these metabolites are produced, contributing to interindividual variability.

Research on koprololiitin is exploratory. While other ellagitannin-derived metabolites, such as urolithins, have been studied for potential antioxidant activity and effects on mitochondrial function, evidence for specific health effects of koprololiitin remains limited. There are no regulatory approvals or clinical uses established for koprololiitin, and safety data are not well defined. Analytical investigations typically employ liquid chromatography–mass spectrometry, with challenges including structural isomerism and low concentrations.

See also: ellagic acid, ellagitannins, urolithins, polyphenols, gut microbiota.