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Clinical trials show an inverse relationship between the consumption of antioxidant-rich tree nuts and the development of chronic diseases. This study examined antioxidant efficacy of U.S. pecans using a modified cellular antioxidant activity (CAA) assay with comparisons to data from in vitro antioxidant assays (hydrophilic-oxygen radical absorbance capacity {H-ORACFL} and ferric reducing antioxidant power {FRAP}). Crude phenolic extracts from both raw and roasted pecans were analyzed. In the CAA assay, pecan phenolics were taken up by human colorectal adenocarcinoma (Caco-2) cells and bestowed CAA, determined by monitoring the fluorescence of 2′,7′-dichlorofluorescein. Phenolics (25–100 μg/mL) demonstrated a reduction in fluorescence by 37–69% for raw and 26–68% for roasted pecans. The primary active phenolic constituents were determined by high-performance liquid chromatography–electrospray ionization–mass spectrometry (HPLC–ESI–MS) to be epi(catechin) dimers and trimers. These oligomeric procyanidins, ranging in size from 560 to 840 g/mol appear to be small enough for cellular uptake, showing pecans are an effective antioxidant in biological systems, regardless of roasting.

In vitro assays are widely used to analyze the antioxidant potential of compounds, but they cannot accurately predict antioxidant behavior in living systems. Cell-based assays, like the cellular antioxidant activity (CAA) assay, are gaining importance as they provide a biological perspective. When the CAA assay was employed to study phenolic antioxidants using hepatocarcinoma (HepG2) cells, quercetin showed antioxidant activity in HepG2 cells; 25 and 250μM quercetin reduced fluorescence by 17.1±0.9% and 58.6±2.4%, respectively. (+)-Catechin, a phenolic antioxidant present in many foods, bestowed virtually no CAA in HepG2 cells. When Caco-2 cells were employed, more robust antioxidant activity was observed; 50μM (+)-catechin and quercetin reduced fluorescence by 54.1±1.4% and 63.6±0.9%, respectively. Based on these results, likely due to differences in active membrane transport between the cell types, the Caco-2-based CAA assay appears to be a more appropriate method for the study of certain dietary phenolics.

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.

Inflammation is linked to numerous chronic disease states. Phenolic compounds have attracted attention because a number of these compounds possess anti-inflammatory properties. A phenolic crude extract was prepared from pecans and separated by Sephadex LH-20 column chromatography into low- and high-molecular-weight (LMW/HMW) fractions. Anti-inflammatory properties of these fractions were assessed in LPS-stimulated RAW 264.7 murine macrophage cells. NO and reactive oxygen species (ROS) production was monitored after 3 different experimental protocols: (1) pre-treatment with Escherichia coli O111:B4 lipopolysaccharide (LPS); (2) pre-treatment with a pecan crude extract and its fractions; and (3) co-incubation of LPS with a pecan crude extract and its fractions. The LMW fraction displayed a dose-dependent decrease in NO production and a significant decrease from the LPS control in ROS production when cells were either co-incubated with or pre-treated with LPS. The phenolics were characterized by HPLC to help identify those responsible for the observed effect.

Plant-based polyphenolics have been reported to bestow health benefits when consumed, which are partially ascribed to their antioxidant activity. Yet, many current in vitro chemical assays to characterize antioxidant potential do not truly reflect the physiological properties of food antioxidants in vivo. The present study employed biological approaches, including a cellular antioxidant activity (CAA) and protein glycation assays, to offer an improved picture of antioxidant potential of phenolic extracts from Georgia peach cultivars. The phenolic extracts from two peach varieties, showing contrasting antioxidant capacities according to hydrophilic-oxygen radical absorbance capacity (H-ORACFL) and ferric reducing antioxidant power (FRAP) assays, exhibited significant differences in two biological tests when the assays were performed on a fresh weight basis. The procyanidins fraction displayed notable antioxidant capacity, when compared to other phenolic classes in the peach extract, in these two biologically relevant assays.

5 Páginas.-- 1 Figura, As many studies are exploring the association between ingestion of bioactive compounds and decreased risk of non-communicable diseases, the scientific community continues to show considerable interest in these compounds. In addition, as many non-nutrients with putative health benefits are reducing agents, hydrogen donors, singlet oxygen quenchers or metal chelators, measurement of antioxidant activity using in vitro assays has become very popular over recent decades. Measuring concentrations of total phenolics, flavonoids, and other compound (sub)classes using UV/Vis spectrophotometry offers a rapid chemical index, but chromatographic techniques are necessary to establish structure-activity. For bioactive purposes, in vivo models are required or, at the very least, methods that employ distinct mechanisms of action (i.e., single electron transfer, transition metal chelating ability, and hydrogen atom transfer). In this regard, better understanding and application of in vitro screening methods should help design of future research studies on ‘bioactive compounds’.

Polyphenolics (PP) from bearberry (Arctostaphylos uva-ursi L. Sprengel) leaves were extracted with 70% (v/v) acetone. The lyophilised crude PP extract was then separated on a Sephadex LH-20 column using first 95% (v/v) ethanol as a mobile phase to elute fraction I low in tannins, and then 50% (v/v) acetone to elute fraction II rich in hydrolysable and condensed tannins. Bovine serum albumin (BSA) was effectively precipitated by PP in the bearberry-leaf crude extract and fraction II at pH values between 3.8 and 4.5. A statistically significant (P = 0.0001) linear relationship exists between the amount of PP-protein complex formed and the quantity of PP added to the reaction mixture. The slope values of these lines indicate that fraction II from the crude extract was a more effective precipitant of proteins than other examined preparations. Based on the quantity of gelatine, fetuin, and BSA required to inhibit 50% of dye-labelled PP–BSA complex precipitation, gelatine was 3–6 times more effective as a precipitation inhibitor than both unlabelled BSA and fetuin.

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 6.09 μmol Trolox eq./mg fraction (d.w.), whereas the crude extract and fraction I showed 0.75 and 0.33 μmol Trolox eq./mg extract or fraction (d.w.), respectively. The content of total phenolics in fraction II was the highest (338 mg catechin eq./g fraction, d.w.), and the tannin content, as determined by the vanillin/HCl method and expressed as absorbance units at 500 nm per 1 g, 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.

The fatty acid profiles of commercially-grown Runner-type peanut cultivars (i.e., 10 cultivars, n = 151) collected over two production years (2005 and 2006) were determined by gas–liquid chromatography. Eight major fatty acids were identified in the sample set including palmitic (C16:0), stearic (C18:0), oleic (C18:1, ω9), linoleic (C18:2, ω6), arachidic (C20:0), gondoic (C20:1, ω9), behenic (C22:0), and lignoceric (C24:0) acids. Based on the oleic to linoleic acid (O/L) ratio, these cultivars were denoted as normal, mid-, and high-oleic peanut types. Correlation coefficients (r) between the eight major fatty acids identified were generated and revealed an inverse association between oleic and linoleic acids (r = –0.997, P

Antioxidant compounds were extracted from canola meal by subcritical water extraction (SWE) at 110 and 160 °C, hot water extraction (80 °C) and ethanolic (95%, v/v) extraction. The highest extract yields were obtained with SWE at 160 °C. The total phenolics contents and antioxidant capacities of extracts were assessed by the total phenolics assay (using Folin–Ciocalteu’s phenol reagent), the 2,2’-diphenyl-1-picrylhydrazyl radical (DPPH ) scavenging assay, the Trolox equivalent antioxidant capacity (TEAC) method, a β-carotene–linoleic acid (linoleate) model system, and the reducing power assay. Ethanolic extracts exhibited the highest total phenolics contents and antioxidant capacities on a per gram of extract basis. Subcritical water extraction at 160 °C yielded the highest total phenolics contents and antioxidant capacities on a per gram of meal basis. Results from the total phenolics assay and the antioxidant capacity tests were significantly correlated.

The objectives of the present study were to ascertain the nutritional value (i.e., macro and microconstituents) of emu (Dromaius novaehollandiae, Latham) meat and a value-added product derived therefrom. The contents of creatine, creatinine and phosphocreatine in fresh emu meat and the impact of processing on these bioactives during the production of jerky were of particular interest. For comparative purposes, a beef counterpart was prepared. The proximate compositional data indicated that the macroconstituents of emu meat and the fabricated jerky product were not so different from their beef analogues. Analysis of the microconstituents in emu samples revealed that the levels of a number of nutritionally important oil- and water-soluble vitamins and minerals were typical of those for red meat species. The creatine content in emu meat (29.3 mg/g dry matter) was similar to that of beef; slightly higher creatine levels were detected, however, in the emu jerky (22.8 mg/g dry matter) compared to its beef counterpart, and these were significant (P < 0.01) when the data was analysed on a dry weight basis. This demonstrates a potential for the emu meat snack to be considered as a functional food for athletes looking for performance enhancement, and who are interested in consuming greater quantities of creatine from a natural food source.

Ethanolic extracts from the roots of wild licorice (Glycyrrhiza lepidota), narrow-leaved echinacea (Echinacea angustifolia), senega (Polygala senega), leaves of bearberry (Arctostaphylos uva-ursi) and aerial parts of two varieties of horsetail (Equisetum spp.) were prepared and evaluated for their free-radical scavenging capacity and their antioxidant activity, by a number of chemical assays. Assays employed included a b-carotene-linoleic acid (linoleate) model system, reducing power, scavenging effect on the DPPH � free radical and capacity to scavenge hydroxyl free radicals (HO � ), by use of electron paramagnetic resonance (EPR) spectroscopy. The bearberry-leaf extract consistently exhibited the highest antioxidant activity based on the tests performed, and seems to be a promising source of natural antioxidants. The polyphenolic constituents appear to be responsible, at least in part, for the extract’s radical-scavenging capacity. Research is progressing to characterize the antioxidant compounds in the bearberry-leaf extract and their mode of action in imparting antioxidant activity to various food systems. # 2003 Elsevier Ltd. All rights reserved.

The goal of this research was to investigate the change in phenolics content and antioxidant capacity of microencapsulated anthocyanins (ACNs) digested in vitro. Blueberry ACN microcapsules were prepared from two wall materials (whey protein isolate and gum arabic) and ACN powder, previously extracted with three solvent systems (acetonic, ethanolic, methanolic); this was then spray-dried. The physicochemical properties and release characteristics of the microcapsules were evaluated. Rehydrated gum arabic microcapsules retained more total ACNs but less ferric reducing power than did whey protein microcapsules. Ethanolic extracts retained most of the total ACNs while methanolic extracts possessed the highest antioxidant capacity. During in vitro digestion, gum arabic microcapsules had high release rates of phenolics with high antioxidant activity during the gastric phase. Whey protein microcapsules had comparably lower release rates but high antioxidant activity throughout digestion.

Incorporation of ground peanut skins (PS) into peanut butter at 1.25%, 2.5%, 3.75%, and 5.0% (w/w) resulted in a marked concentration-dependent increase in both the total phenolics content (TPC) and antioxidant activity. Using dry-blanched PS to illustrate, the TPC increased by 86%, 357%, 533%, and 714%, respectively, compared to the peanut butter control devoid of PS; the total proanthocyanidins content (TPACs) rose by 633%, 1933%, 3500%, and 5033%, respectively. NP-HPLC detection confirmed that the increase in the phenolics content was attributed to the endogenous proanthocyanidins of the PS, which were characterised as dimers to nonamers by NP-HPLC/ESI-MS. FRAP values increased correspondingly by 62%, 387%, 747%, and 829%, while H-ORAC(FL) values grew by 53%, 247%, 382%, and 415%, respectively. The dietary fibre content of dry-blanched PS was ~55%, with 89-93% being insoluble fibre. Data revealed that PS addition enhances the antioxidant capacity of the peanut butter, permits a "good source of fibre" claim, and offers diversification in the market's product line.

The chemical structure of preformed cooked cured-meat pigment (CCMP), which is believed to be the pigment of thermally-processed nitrite-cured meat, was investigated by a novel titration methodology. Electronic spectra of reduced haemin and its nitrosyl derivative were recorded in the visible region in an aqueousor a dimethyl sulphoxide-medium. Changes in the electronic spectrum of reduced haemin upon gradual addition of aliquots of a saturated solution of nitric oxide (NO) revealed that only one molecule of NO ligates itself to the iron of the porphyrin molecule. A similar conclusion was reached from the infrared studies of CCMP, which revealed the presence of only one NO stretching band. Thus, preformed CCMP is irrefutably a mononitrosyl, not a dinitrosyl, derivative of reduced haemin. This conclusion is further supported by an independent electron paramagnetic resonance study of CCMP, which showed that the pigment was a pentacoordinated paramagnetic complex.

Cod offal from Atlantic species (Gadus morhua) during the intense summer inshore fisheries, June–August, was analyzed for its chemical composition and energy value. The crude protein content of the samples was 14·3% and this included 2·55% collagen. The total lipid content of the offal was 4·3% and its ash content averaged 3·95%. Thus, the energy value of the offal was calculated as 413 kJ/100 g. The offal had an increased content of glycine, alanine, serine, proline and hydroxyproline as compared to the cod muscle proteins. Based on the content of selected amino acids, the calculated PER value for the offal was 1·88–2·36 as compared to 2·86–3·24 for the cod muscle. The fatty acid composition of the offal was similar to that of the cod-liver oil.

The colour characteristics of comminuted pork treated with pre-formed cooked cured-meat pigment and protoporphyrin-IX (PP-IX) were compared to that of nitrite-cured meat. Hunter L, a, b values indicated that pigment-treated meat, at 12 ppm level, upon cooking, closely resembled that of nitrite-cured meat. Addition of sodium tripolyphosphate (STPP) and/or sodium acid pyrophosphate (SAPP) did not have a significant (P