Prunella vulgaris is a traditional herb commonly consumed as brewed tea in Asian and European countries. The therapeutic antioxidant and anti-inflammatory activity of this traditional herbal tea are relatively unknown. The study examined, using established in vivo markers of oxidative stress and inflammation, the antioxidant and anti-inflammatory actions of Prunella vulgaris tea in-vitro, which were compared with those measured from green and black tea. Prunella vulgaris tea significantly decreased the human neutrophilic formations of F2-isoprostanes, lipid hydroperoxides, and leukotriene B4, while increasing those of nitrite and nitrate. The measured antioxidant and anti-inflammatory effects were greater than those from green and black tea. Prunella vulgaris tea exerted antioxidant effects via electron-transfer radical scavenging and up-regulated antioxidant enzyme activities, and anti-inflammatory effects by modulating 5-lipoxygenase, myeloperoxidase, and inducible nitric oxide pathways. The study results provide evidence supporting further investigations in the in vivo conditions.

The study evaluated the individual and combined influence of polyphenol (quercetin), prebiotic (galactooligosaccharide), probiotic ( Lactobacillus acidophilus), and/ or postbiotic (inanimate Lactobacillus acidophilus) on the cellular oxidative status of CACO-2 intestinal epithelial cells. The CACO-2 cells were treated with quercetin (1 µmol L-1), galactooligosaccharide (4 mg mL-1), Lactobacillus acidophilus (2 x 106 CFU mL-1), and/or inanimate Lactobacillus acidophilus (2 x 106 CFU mL-1) individually and in all combinations over twenty four hours. Cellular antioxidant capacities (DPPH radical scavenging activity, Oxygen Radical Absorbance Capacity, Total Peroxyl Trapping Potential, and Trolox Equivalent Antioxidant Capacity), antioxidant enzyme activities (superoxide dismutase and peroxidase), and oxidative damages (F2-isoprostanes and lipid hydroperoxides) were measured. Intracellular quercetin and total short-chain fatty acids (acetic, propionic, and butyric acids) were determined. Treatments with quercetin or inanimate Lactobacillus acidophilus exhibited significant greater cellular antioxidant effects compared to those without quercetin or inanimate Lactobacillus acidophilus. Antioxidant capacities of treatments with quercetin and inanimate Lactobacillus acidophilus were significantly stronger than those with either one. Quercetin and short-chain fatty acids accumulated into the CACO-2 cells incubated with quercetin and inanimate Lactobacillus acidophilus, respectively. Polyphenol, probiotic, and postbiotic, individually or interdependently, influenced the oxidative status of intestinal epithelial CACO-2 cells and protected them from oxidative damage.