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BackgroundThis study aims to determine the relationship between the antioxidant and anti-inflammatory activities of the thirteen herbs and two fungi extracts, and their total phenolic and flavonoid contents.MethodsAntioxidant activities were evaluated by four assays: an antioxidant activity assay using Saccharomyces cerevisiae, a DPPH ((2, 2-diphenyl-1-picrylhydrazyl) assay to assess free radical scavenging, an assay assessing ferrous ions or iron (II) chelating ability, and a ferric reducing antioxidant power (FRAP) assay. Total phenolic and flavonoid contents were determined using the Folin-Ciocalteu and aluminium chloride methods, respectively. Anti-inflammatory activities were determined by measuring the inhibition of nitric oxide and TNF-α production in lipopolysaccharide- and interferon-γ-activated J774A.1 macrophages. Their cytotoxicities against macrophages were determined by MTT assay.ResultsA positive linear correlation between antioxidant activities and the total phenolic and flavonoid content of the plant extracts was found. The plant extracts with high phenolic and flavonoid content also exhibited significant anti-inflammatory activity with good cell viability.ConclusionThe selected herbs could be a rich source of antioxidants and free radical scavenging compounds. The levels of phenolic and flavonoid compounds were correlated with the antioxidant and anti-inflammatory activities of the extracts from the herbs.

A new ion chromatographic method that is applicable to the direct determination of UV-absorbing inorganic anions in saline matrixes is described. An octadecylsilica column modified with a zwitterionic surfactant (3-(N,N-dimethylmyristylammonio)propanesulfonate) is used as the stationary phase, and an electrolytic solution is used as the eluent. Under these conditions, the matrix species (such as chloride and sulfate) are only retained weakly and show little or no interference. It is proposed that a binary electrical double layer (EDL) is established by retention of the eluent cations on the negatively charged (sulfonate) functional groups of the zwitterionic surfactant (forming a cation-EDL) and by retention of eluent anions on the positively charged (quaternary ammonium) functional groups of the zwitterionic surfactant (forming an anion-EDL). Sample anions are able to distribute into the cation-EDL and to form ion pairs with the EDL cations, while at the same time experiencing repulsion from the anion-EDL. Anions are therefore eluted in order of increased propensity to form ion pairs. The method has been applied to the determination of bromide, nitrate, and iodide in artificial seawater, giving detection limits of 0.75 ppb for bromide, 0.52 ppb for nitrate, and 0.8 ppb for iodide using UV absorbance detection at 210 nm and relative standard deviations of <1.2%. Real seawater samples have also been analyzed successfully.In a series of previous studies 1-7 employing stationary phases coated with zwitterionic surfactants (i.e., those containing both positively and negatively charged functional groups but carrying no formal net charge), it has been demonstrated that inorganic anions can be separated using pure water as eluent, with unique separation selectivity. This method has been termed electrostatic ion chromatography (EIC), and the separation has been attributed to a simultaneous electrostatic attraction and repulsion mechanism occurring at both the positive and the negative charges on the stationary phase. A drawback of EIC is that when the sample contains multiple anions and cations, each analyte anion may be eluted as more than one peak, with each peak being a specific combination of the anion with one of the cations of the sample. Recently, we showed 8 that addition of a small quantity of a suitable electrolyte to the eluent causes analyte anions to be eluted only as a single peak, irrespective of the number and type of cations in the sample. In the present study, we have investigated the separation mechanism in more detail and have applied the method to the determination of nitrate, bromide, and iodide in seawater.The determination of nitrate, bromide, and iodide in seawater is of importance to oceanographic research. 9-11 Ion-exchange chromatography (IEC) is generally inapplicable to this analysis for several reasons. First, the large amount of matrix ions (chloride, sulfate) saturate the active sites of the stationary phase and thereby impede the separation of the target analytes. Second, the high ionic...