Despite the promising antioxidant action of Lamiaceae herbs in vitro, human studies on these potential sources of dietary antioxidants have remained scarce. In this work, the phenolic acids recovered in human urine after single ingestion of Origanum onites extract were analyzed. The excretion was increased 4- and 2-fold during 0-24 and 24-48 h of the follow-up, respectively. The mean increase i...

background: considering the wide consumption of some synthetic antioxidants and their probable negative health effects, in this study, the protective effects of satureja hortensis l. extracts in stabilizing soybean oil against oxidation at different concentrations (200 and 400 ppm) were tested. methods: the aerial parts of s. hortensis l. were collected from isfahan province and extracted with ...

BACKGROUND Phenolic compounds are widely distributed in plant kingdom and constitute one of the most important classes of natural and synthetic antioxidants. In the present study fifty one natural and synthetic structurally variant phenolic, enolic and anilinic compounds were examined as antioxidants and radical scavengers against DPPH, hydroxyl and peroxyl radicals. The structural diversity of...

The incorporation of nitrogen atoms into the aromatic ring of phenolic compounds has enabled the development of some of the most potent radical-trapping antioxidants ever reported. These compounds, 3-pyridinols and 5-pyrimidinols, have stronger O-H bonds than equivalently substituted phenols, but possess similar reactivities toward autoxidation chain-carrying peroxyl radicals. These attributes ...

Phenolic antioxidants inhibit the induction of inflammatory cytokines by inflammatory stimuli. Here, we analyzed the mechanism by which the antioxidants inhibit LPS-induced expression of tumor necrosis factor alpha (TNFalpha) in macrophages. Hydroquinone and tert-butyl hydroquinone, prototypes of phenolic antioxidants, block lipopolysaccharide (LPS)-induced transcription of TNFalpha and a nucle...

Antioxidant capacities of 56 selected Chinese medicinal plants were evaluated using the Trolox equivalent antioxidant capacity (TEAC) and ferric reducing antioxidant power (FRAP) assays, and their total phenolic content was measured by the Folin-Ciocalteu method. The strong correlation between TEAC value and FRAP value suggested that the antioxidants in these plants possess free radical scaveng...

An air–assisted liquid–liquid microextraction method for the extraction and preconcentration of trace amounts of some synthetic phenolic antioxidants in biological fluids followed by their determination by gas chromatography–flame ionization detection has been reported. In this method the target analytes are extracted into a few microliters of carbon tetrachloride (extraction solvent) from an a...

Hydroxycinnamic acids (such as ferulic, caffeic, sinapic, and p-coumaric acids) are a group of compounds highly abundant in food that may account for about one-third of the phenolic compounds in our diet. Hydroxycinnamic acids have gained an increasing interest in health because they are known to be potent antioxidants. These compounds have been described as chain-breaking antioxidants acting t...