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Phenolic compounds from the leaves of the bearberry plant (Arctostaphylos uva-ursi L. Sprengel) were extracted into 95% (v/v) ethanol. Tannin fractions were obtained by Sephadex LH-20 column chromatography using 50% (v/v) acetone as the mobile phase. The tannin fraction was then further characterised by size exclusion high-performance liquid chromatography (SE-HPLC) on a TSK G2000SWXL column with a mobile phase comprising 45% acetonitrile and 0.1% (v/v) TFA. The chromatography revealed the presence of additional phenolic compounds in the tannin fractions which arc not proanthocyanidins (i.e. condensed tannins). [ABSTRACT FROM AUTHOR]

Summary [ABSTRACT FROM AUTHOR]

The extraction and measurement of all six forms of inositol phosphates (InsPs) in almond meal and brown skins were improved from existing methods by pH adjustment, supplementation of EDTA, and rapid analysis via anion-exchange high-performance liquid chromatography coupled with electrospray ionization mass spectrometry. The quantity of InsPs in six major almond cultivars ranged from 8 to 12 μmol/g in the meal and 5 to 14 μmol/g in the brown skins. InsP 6 was the dominant form, but lower forms still accounted for ∼20% of the total InsPs molar concentration in a majority of the samples. InsPs contributed 32–55% of the organic phosphorus content and 20–38% of the total phosphorus content in the meal. In brown skins, these ranges were 44–77% and 30–52%, respectively. The successful application of this analytical method with almonds demonstrates its potential use for re-examination of the reported phytic acid contents in many other tree nuts, legumes, grains, and complex foods. [ABSTRACT FROM AUTHOR]

High-performance liquid chromatography coupled with electrospray ionization mass spectrometry (HPLC–ESI–MS) was utilized for the rapid, on-line detection of all six forms of inositol phosphate (InsP) in seven major tree nuts (i.e., cashews, Brazil nuts, macadamias, walnuts, pecans, pistachios, hazelnuts) and three grain components that are allegedly rich in phosphorus (wheat aleurone, rice bran, corn germ). The total InsP levels ranged from 3 to 20 μmol/g in the tree nuts and from 10 to 97 μmol/g in the grain components. While inositol hexakisphosphate was the predominant form in all samples, at least 20% of the InsP molar concentration comprised lower forms of InsPs. In tree nuts, InsPs accounted for 18–59% of the organic phosphorus content and 12–46% of the total phosphorus content. For grain samples, these values ranged from 66–97% and 58–80%, respectively. Significant differences in InsP levels among tree nuts underline the need for further investigation of InsPs in this food group, particularly with regard to different cultivars, growing conditions, and processing conditions. HPLC–ESI–MS offered a sensitive and time-efficient detection approach for InsPs in various complex nut and grain matrices, highlighting its potential application for many other sample types. [ABSTRACT FROM AUTHOR]

Abstract: Phenolics were extracted from green lentil seeds with 80% (v/v) aqueous acetone, and the resultant extracts were further separated on a Sephadex® LH-20 column. Fraction I, comprising low-molecular-weight phenolics, was eluted from the column with 95% (v/v) ethanol. Fraction II, consisting predominantly of tannins, was obtained using acetone:water (1:1; v/v) as the mobile phase. Phenolic compounds present in the preparations showed antioxidant and radical-scavenging properties as revealed by a β-carotene-linoleate model system, the total antioxidant activity (TAA) method, the DPPH scavenging activity assay, and a reducing power assay. Data from these tests showed the greatest efficacies coming from the tannins (i.e., fraction II); the mean TAA of the tannin fraction was 6.09μmol Trolox eq./mg fraction (d.w.), whereas the crude extract and fraction I showed 0.75 and 0.33μmolTroloxeq./mg extract or fraction (d.w.), respectively. The content of total phenolics in fraction II was the highest (338mgcatechineq./g fraction, d.w.), and the tannin content, as determined by the vanillin/HCl method and expressed as absorbance units at 500nm per 1g, was 252. Twenty compounds (hydroxycinnamates, procyanidins, gallates, flavonols, dihydroflavonols, dihydrochalcones) were identified in the crude extracts by HPLC-PAD and HPLC–ESI-MS techniques. Catechin and epicatechin glucosides, procyanidin dimers, quercetin diglycoside, and trans-p-coumaric acid were the dominant phenolics in green lentils. [Copyright &y& Elsevier]