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Phenolic compounds were extracted from red lentil seeds using 80% (v/v) aqueous acetone. The crude extract was applied to a Sephadex LH-20 column. Fraction 1, consisting of sugars and low-molecular-weight phenolics, was eluted from the column by ethanol. Fraction 2, consisting of tannins, was obtained using acetone-water (1:1; v/v) as the mobile phase. Phenolic compounds present in the crude extract and its fractions demonstrated antioxidant and antiradical activities as revealed from studies using a β- carotene-linoleate model system, the total antioxidant activity (TAA) method, the DPPH radical-scavenging activity assay, and a reducing power evaluation. Results of these assays showed the highest values when tannins (fraction 2) were tested. For instance, the TAA of the tannin fraction was 5.85 μmol Trolox® eq./mg, whereas the crude extract and fraction 1 showed 0.68 and 0.33 μmol Trolox® eq./mg, respectively. The content of total phenolics in fraction 2 was the highest (290 mg/g); the tannin content, determined using the vanillin method and expressed as absorbance units at 500 nm per 1 g, was 129. There were 24 compounds identified in the crude extract using an HPLC-ESI-MS method: quercetin diglycoside, catechin, digallate procyanidin, and p-hydroxybenzoic were the dominant phenolics in the extract. [ABSTRACT FROM AUTHOR]

Three oilseed radish (Raphanus sativus (cv. Daikon, China Rose, and German]) cultivars from two research farms in Saskatchewan, Canada, were analysed for their tocopherol contents, The findings were compared to tocopherol levels determined in an oriental mustard, a field mustard, a canola, and an arugula cultivar. HPLC data revealed that the oilseed radish cultivars were devoid of both α- and β-tocopherol, but contained γ- tocopherol at levels similarly found in many canola varieties (i.e., 11.4 rag/100 g seed). In addition, they possessed a small content of δ-tocopherol (-1-1.4 g/100 g seed). Application of a YMC™ Carotenoid (C30) column successfully separated and allowed quantification of all tocopherol isomers using reversed-phase HPLC with UV detection in < 15 min. [ABSTRACT FROM AUTHOR]

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]