A phenolic acid with anti-inflammatory activity; formed via microbial metabolism of aromatic amino acids and polyphenolic compounds, including flavonoid glycosides, by gut microbiota; inhibits seawater instillation-induced increases in TNF-α, IL-1β, and IL-6 levels in lung tissue and white blood cell numbers in BALF and prevents lung edema in a rat model of acute lung injury at 100 mg/kg; levels are increased and decreased in serum and urine, respectively, in rats fed a high-fat diet; serum levels are increased in patients with stage III pancreatic cancer