Showing papers in "Journal of Agricultural and Food Chemistry in 2010"

Compositional Analysis of Lignocellulosic Feedstocks. 1. Review and Description of Methods

Abstract: As interest in lignocellulosic biomass feedstocks for conversion into transportation fuels grows, the summative compositional analysis of biomass, or plant-derived material, becomes ever more important. The sulfuric acid hydrolysis of biomass has been used to measure lignin and structural carbohydrate content for more than 100 years. Researchers have applied these methods to measure the lignin and structural carbohydrate contents of woody materials, estimate the nutritional value of animal feed, analyze the dietary fiber content of human food, compare potential biofuels feedstocks, and measure the efficiency of biomass-to-biofuels processes. The purpose of this paper is to review the history and lineage of biomass compositional analysis methods based on a sulfuric acid hydrolysis. These methods have become the de facto procedure for biomass compositional analysis. The paper traces changes to the biomass compositional analysis methods through time to the biomass methods currently used at the National Renewable Energy Laboratory (NREL). The current suite of laboratory analytical procedures (LAPs) offered by NREL is described, including an overview of the procedures and methodologies and some common pitfalls. Suggestions are made for continuing improvement to the suite of analyses.

Immobilization of Heavy Metal Ions (CuII, CdII, NiII, and PbII) by Broiler Litter-Derived Biochars in Water and Soil

Abstract: Chars, a form of environmental black carbon resulting from incomplete burning of biomass, can immobilize organic contaminants by both surface adsorption and partitioning mechanisms. The predominance of each sorption mechanism depends upon the proportion of organic to carbonized fractions comprising the sorbent. Information is currently lacking in the effectiveness of char amendment for heavy metal immobilization in contaminated (e.g., urban and arms range) soils where several metal contaminants coexist. The present study employed sorbents of a common biomass origin (broiler litter manure) that underwent various degrees of carbonization (chars formed by pyrolysis at 350 and 700 degrees C and steam-activated analogues) for heavy metal (Cd(II), Cu(II), Ni(II), and Pb(II)) immobilization in water and soil. ATR-FTIR, (1)H NMR, and Boehm titration results suggested that higher pyrolysis temperature and activation lead to the disappearance (e.g., aliphatic -CH(2) and -CH(3)) and the formation (e.g., C-O) of certain surface functional groups, portions of which are leachable. Both in water and in soil, pH increase by the addition of basic char enhanced the immobilization of heavy metals. Heavy metal immobilization resulted in nonstoichiometric release of protons, that is, several orders of magnitude greater total metal concentration immobilized than protons released. The results suggest that with higher carbonized fractions and loading of chars, heavy metal immobilization by cation exchange becomes increasingly outweighed by other controlling factors such as the coordination by pi electrons (C=C) of carbon and precipitation.

Thorough study of reactivity of various compound classes toward the Folin-Ciocalteu reagent.

Abstract: A thorough study was done to test the reactivity of the Folin−Ciocalteu (F-C) reagent toward various compound classes. Over 80 compounds were tested. Compound classes included phenols, thiols, vitamins, amino acids, proteins, nucleotide bases, unsaturated fatty acids, carbohydrates, organic acids, inorganic ions, metal complexes, aldehydes, and ketones. All phenols, proteins, and thiols tested were reactive toward the reagent. Many vitamin derivatives were also reactive, as were the inorganic ions Fe+2, Mn2+, I−, and SO32−. Other compounds showing reactivity included the nucleotide base guanine and the trioses glyceraldehyde and dihydroxyacetone. Copper complexation enhanced the reactivity of salicylate derivatives toward the reagent, whereas zinc complexation did not. Several amino acids and sugars that were reported to be reactive toward the F-C reagent in earlier studies were found not to be reactive in this study, at least in the concentrations used. Reaction kinetics of each compound with the F-C rea...

Blueberry Supplementation Improves Memory in Older Adults

Abstract: The prevalence of dementia is increasing with expansion of the older adult population. In the absence of effective therapy, preventive approaches are essential to address this public health problem. Blueberries contain polyphenolic compounds, most prominently anthocyanins, which have antioxidant and anti-inflammatory effects. In addition, anthocyanins have been associated with increased neuronal signaling in brain centers, mediating memory function as well as improved glucose disposal, benefits that would be expected to mitigate neurodegeneration. This study investigated the effects of daily consumption of wild blueberry juice in a sample of nine older adults with early memory changes. At 12 weeks, improved paired associate learning (p = 0.009) and word list recall (p = 0.04) were observed. In addition, there were trends suggesting reduced depressive symptoms (p = 0.08) and lower glucose levels (p = 0.10). We also compared the memory performances of the blueberry subjects with a demographically matched sample who consumed a berry placebo beverage in a companion trial of identical design and observed comparable results for paired associate learning. The findings of this preliminary study suggest that moderate-term blueberry supplementation can confer neurocognitive benefit and establish a basis for more comprehensive human trials to study preventive potential and neuronal mechanisms.

Consumption of human milk oligosaccharides by gut-related microbes.

Abstract: Human milk contains large amounts of complex oligosaccharides that putatively modulate the intestinal microbiota of breast-fed infants by acting as decoy binding sites for pathogens and as prebiotics for enrichment of beneficial bacteria. Several bifidobacterial species have been shown to grow well on human milk oligosaccharides. However, few data exist on other bacterial species. This work examined 16 bacterial strains belonging to 10 different genera for growth on human milk oligosaccharides. For this propose, a chemically defined medium, ZMB1, was used, which allows vigorous growth of a number of gut-related microorganisms in a fashion similar to complex media. Interestingly, Bifidobacterium longum subsp. infantis, Bacteroides fragilis , and Bacteroides vulgatus strains were able to metabolize milk oligosaccharides with high efficiency, whereas Enterococcus , Streptococcus , Veillonella , Eubacterium , Clostridium , and Escherichia coli strains grew less well or not at all. Mass spectrometry-based glycoprofiling of the oligosaccharide consumption behavior revealed a specific preference for fucosylated oligosaccharides by Bi. longum subsp. infantis and Ba. vulgatus. This work expands the current knowledge of human milk oligosaccharide consumption by gut microbes, revealing bacteroides as avid consumers of this substrate. These results provide insight on how human milk oligosaccharides shape the infant intestinal microbiota.

Biofortification and localization of zinc in wheat grain.

Abstract: Zinc (Zn) deficiency associated with low dietary intake is a well-documented public health problem, resulting in serious health and socioeconomic problems. Field experiments were conducted with wheat to test the role of both soil and foliar application of ZnSO4 in Zn concentration of whole grain and grain fractions (e.g., bran, embryo and endosperm) in 3 locations. Foliar application of ZnSO4 was realized at different growth stages (e.g., stem elongation, boot, milk, dough stages) to study the effect of timing of foliar Zn application on grain Zn concentration. The rate of foliar Zn application at each growth stage was 4 kg of ZnSO4·7H2O ha−1. Laser ablation (LA)-ICP-MS was used to follow the localization of Zn within grain. Soil Zn application at a rate of 50 kg of ZnSO4·7H2O ha−1 was effective in increasing grain Zn concentration in the Zn-deficient location, but not in the locations without soil Zn deficiency. In all locations, foliar application of Zn significantly increased Zn concentration in whole ...

Content of insoluble bound phenolics in millets and their contribution to antioxidant capacity.

Abstract: Soluble and insoluble-bound phenolic extracts of several varieties of millet (kodo, finger, foxtail, proso, pearl, and little millets) whole grains were evaluated for their phenolic contents and antioxidative efficacy using trolox equivalent antioxidant capacity (TEAC), reducing power (RP), and beta-carotene-linoleate model system as well as ferrous chelating activity. In addition, ferulic and p-coumaric acids were present in soluble and bound phenolic fractions of millets, and their contents were determined using high-performance liquid chromatography (HPLC) and HPLC-mass spectrometry (MS). Kodo millet had the highest total phenolic content, whereas proso millet possessed the least. All millet varieties showed high antioxidant activities, although the order of their efficacy was assay dependent. HPLC analysis of millet phenolic extracts demonstrated that the bound fractions contained more ferulic and p-coumaric acids compared to their soluble counterparts. The results of this study showed that soluble as well as bound fractions of millet grains are rich sources of phenolic compounds with antioxidant, metal chelating, and reducing power. The potential of whole millets as natural sources of antioxidants depends on the variety used. The importance of the insoluble bound fraction of millet as a source of ferulic acid and p-coumaric acid was established, and their contribution to the total phenolic content must be taken into account in the assessment of the antioxidant activity of millets.

Amino acid composition and antioxidant properties of pea seed ( Pisum sativum L.) enzymatic protein hydrolysate fractions.

Abstract: The amino acid composition and antioxidant activities of peptide fractions obtained from HPLC separation of a pea protein hydrolysate (PPH) were studied. Thermolysin hydrolysis of pea protein isolate and ultrafiltration (3 kDa molecular weight cutoff membrane) yielded a PPH that was separated into five fractions (F1−F5) on a C18 reverse phase HPLC column. The fractions that eluted later from the column (F3−F5) contained higher contents hydrophobic and aromatic amino acids when compared to fractions that eluted early or the original PPH. Fractions F3−F5 also exhibited the strongest radical scavenging and metal chelating activities; however, hydrophobic character did not seem to contribute to reducing power of the peptides. In comparison to glutathione, the peptide fractions had significantly higher (p < 0.05) ability to inhibit linoleic acid oxidation and chelate metals. In contrast, glutathione had significantly higher (p < 0.05) free radical scavenging properties than the peptide fractions.

Characterization of phenolic composition in Lamiaceae spices by LC-ESI-MS/MS.

Abstract: A total of 38 phenolic compounds in the solid/liquid extracts of five Lamiaceae spices, rosemary, oregano, sage, basil, and thyme, were identified in the present study using LC-ESI-MS/MS. These compounds were distributed in four major categories, namely, hydroxycinnamic acid derivatives, hydroxybenzoic acid derivatives, flavonoids, and phenolic terpenes. Among them, the category of flavonoids was the largest, with 17 compounds. Identification of the phenolic compounds was carried out by comparing retention times and mass spectra with those of authentic standards. If standards were unavailable, phenolic compounds were identified on the basis of accurate mass of pseudomolecular [M − H]− ions and tandem mass spectrometry (MS/MS) data. The results of accurate mass measurements fit well with the elemental composition of the compounds. The diagnostic fragmentation patterns of the compounds during collision-induced dissociation (CID) elucidated the structural information of the compounds analyzed.

Identification of flavonoid and phenolic antioxidants in black currants, blueberries, raspberries, red currants, and cranberries.

Abstract: The antioxidant capacity (AOC) of black currant, blueberry, raspberry, red currant, and cranberry extracts was determined using the FRAP assay. In addition, the vitamin C content of the berries was determined and phenolic and polyphenolic compounds in the extracts were analyze by reversedphase HPLC-PDA-MS 3 and by reversed-phase HPLC-PDA with an online antioxidant detection system. A complex spectrum of anthocyanins was the major contributor to the AOC of black currants and blueberries, whereas the lower AOC of red currants and cranberries was due mainly to a reduced anthocyanin content. Raspberries also had a lower anthocyanin content than black currants and blueberries, but there was only a slight decline in the AOC because of the presence of the ellagitannins sanguin H-6 and lambertianin C, which were responsible for 58% of the HPLCAOC of the berries. Vitamin C was responsible for 18-23% of the HPLC-AOC of black currants, red currants, and cranberries and for 11% of that of raspberries but did not contribute to the AOC of the blueberry extract that was examined. Seven percent of the HPLC-AOC of the cranberry extract was attributable to procyanidin dimers. However, the contribution of polymeric proanthocyanidins to the AOC of the five berries was not determined as when analyzed by reversed-phase HPLC these high molecular weight flavan-3-ols are either retained by the column or eluted as a broad unresolved band.

New mathematical model for interpreting pH-stat digestion profiles: impact of lipid droplet characteristics on in vitro digestibility.

Abstract: The pH-stat method is commonly used to characterize the in vitro digestibility of lipids under simulated small intestine conditions. This method measures the fraction of free fatty acids (FFA) released from triacylglycerols over time. A new mathematical model has been developed to characterize the FFA versus time profiles generated by the pH-stat method, which can be used to quantify the influence of physicochemical parameters on the rate (k) and extent (ϕmax) of lipid digestion. In this model, k is the amount of FFA produced per unit time per unit surface area, whereas ϕmax is the maximum fraction of digestible FFAs released. This model is used to quantify the influence of lipid droplet characteristics (size, concentration, composition, and emulsifier type) on the digestion of emulsified lipids. The rate (k) of lipid digestion increased with decreasing lipid content (from 2.5 to 0.5 wt %), increasing droplet diameter (from d = 200−15000 nm), and decreasing fatty acid molecular weight (MCT versus corn oil...

X-ray Absorption Spectroscopy (XAS) Corroboration of the Uptake and Storage of CeO2 Nanoparticles and Assessment of Their Differential Toxicity in Four Edible Plant Species

Abstract: Fate, transport, and possible toxicity of cerium oxide nanoparticles (nanoceria, CeO(2)) are still unknown. In this study, seeds of alfalfa (Medicago sativa), corn (Zea mays), cucumber (Cucumis sativus), and tomato (Lycopersicon esculentum) were treated with nanoceria at 0-4000 mg L(-1). The cerium uptake and oxidation state within tissues were determined using inductively coupled plasma-optical emission spectroscopy (ICP-OES) and X-ray absorption spectroscopy (XAS), respectively. The germination rate and root elongation were also determined. Results showed that nanoceria significantly reduced corn germination (about 30% at 2000 mg L(-1); p < 0.05), and at 2000 mg L(-1), the germination of tomato and cucumber was reduced by 30 and 20%, respectively (p < 0.05). The root growth was significantly promoted (p < 0.05) by nanoceria in cucumber and corn but reduced (p < 0.05) in alfalfa and tomato. At almost all concentrations, nanoceria promoted shoot elongation in the four plant species. XAS data clearly showed the nanoceria within tissues of the four plant species. To the authors' knowledge, this is the first report on the presence nanoceria within plants.

Phenolic Profiles and Antioxidant Activity of Black Rice Bran of Different Commercially Available Varieties

Abstract: Increased consumption of whole grains has been associated with reduced risk of developing major chronic diseases. These health benefits have been attributed in part to their unique phytochemicals. Previous studies on black rice mainly focused on anthocyanins. Little is known about the phytochemical profiles and antioxidant activities of different black rice varieties. The objective of this study was to determine the phytochemical profiles and antioxidant activity of rice bran samples from 12 diverse varieties of black rice. The free, bound, and total phenolic contents of black rice bran samples ranged from 2086 to 7043, from 221.2 to 382.7, and from 2365 to 7367 mg of gallic acid equiv/100 g of dry weight (DW), respectively. The percentage contribution of free phenolics to the total ranged from 88.2 to 95.6%. The average values of free, bound, and total phenolic contents of black rice bran were 8, 1.5, and 6 times higher than those of white rice bran, respectively (p < 0.05). The free, bound, and total fl...

Occurrence of mycotoxins in feed as analyzed by a multi-mycotoxin LC-MS/MS method.

Abstract: Crops used for animal feed can be easily contaminated by fungi during growth, harvest, or storage, resulting in the occurrence of mycotoxins. Because animal feed plays an important role in the food safety chain, the European Commission has set maximum levels for aflatoxin B1 and recommended maximum levels for deoxynivalenol, zearalenone, ochratoxin A, and the sum of fumonisin B1 and B2. A multimycotoxin LC-MS/MS method was developed, validated according to Commission Decision 2002/657/EC and EN ISO 17025 accredited for the simultaneous detection of 23 mycotoxins (aflatoxin-B1, aflatoxin-B2, aflatoxin-G1, aflatoxin-G2, ochratoxin A, deoxynivalenol, zearalenone, fumonisin B1, fumonisin B2, fumonisin B3, T2-toxin, HT2-toxin, nivalenol, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, diacetoxyscirpenol, fusarenon-X, neosolaniol, altenuene, alternariol, alternariol methyl ether, roquefortine-C, and sterigmatocystin) in feed. The decision limits of the multimycotoxin method varied from 0.7 to 60.6 microg/kg. The apparent recovery and the results of the precision study fulfilled the performance criteria as set in Commission Decision 2002/657/EC. The analysis of three different feed matrices (sow feed, wheat, and maize) provided a good basis for the evaluation of the toxin exposure in animal production. In total, 67 samples out of 82 (82%) were contaminated; type B-trichothecenes and fumonisins occurred most often. The majority of the infected feed samples (75%) were contaminated with more than one type of mycotoxin.

Lignin Extraction from Straw by Ionic Liquids and Enzymatic Hydrolysis of the Cellulosic Residues

Abstract: Lignocellulose is a promising starting material for bioproducts, ranging from biofuels to specialty chemicals; however, lignocellulose is resistant to enzymatic degradation. Overcoming this resistance is therefore an important priority for the development of the lignocellulosic biorefinery concept. In this work, 1-ethyl-3-methylimidazolium acetate ([emim]Ac) was selected from six ionic liquid candidates for the extraction of lignin from triticale and wheat straw and flax shives. Lignin extractability, composition, and cellulose enzymatic digestibility of the residues after extraction by [emim]Ac were determined at various temperatures (70−150 °C) and time intervals (0.5−24 h). The optimal result (52.7% of acid insoluble lignin in triticale straw) was obtained at 150 °C after 90 min, yielding >95% cellulose digestibility of the residue. Little cellulose was extracted, and the extracted lignin was recovered by acid precipitation. Selective extraction of lignin by ionic liquids is a potentially efficient tec...

Sodium caseinate stabilized zein colloidal particles

Abstract: The present work deals with the preparation and stabilization of zein colloidal particles using sodium caseinate as electrosteric stabilizer. Colloidal particles with well-defined size range (120-150 nm) and negative surface potential (-29 to -47 mV) were obtained using a simple antisolvent precipitation method. Due to the presence of caseinate, the stabilized colloidal particles showed a shift of isoelectric point (IEP) from 6.0 to around pH 5.0 and thus prevent the aggregation of zein near its native IEP (pH 6.2). The particles also showed good stability to varying ionic strength (15 mM-1.5 M NaCl). Furthermore, stabilized particles retained the property of redispersibility after drying. In vitro protein hydrolysis study confirmed that the presence of caseinate did not alter the digestibility of zein. Such colloidal particles could potentially serve as all-natural delivery systems for bioactive molecules in food, pharmaceutical, and agricultural formulations.

Alternative Reaction Mechanism for the Cross-Linking of Gelatin with Glutaraldehyde

Abstract: FT-IR, in combination with residual amino group determination using a fluorescence technique, has been used to investigate the chemical functional groups involved in the cross-linking reaction betw...

Systematic Analysis of the Content of 502 Polyphenols in 452 Foods and Beverages: An Application of the Phenol-Explorer Database

Abstract: Considerable information on polyphenol content in foods is scattered in up to 1000 peer-reviewed publications and is therefore not easily exploited. Over 60000 food composition data have been collected from this literature and stored in the new Phenol-Explorer database ( www.phenol-explorer.eu ). Thirty-seven thousand data were selected after evaluation and aggregated separately according to 5 categories of analytical methods to generate mean content values for 502 compounds (glycosides, esters, or aglycones) in 452 foods. These data are exploited here in a first systematic analysis of the content in foods of these 502 polyphenols. These data will be useful for epidemiologists to determine polyphenol intake and associations with health and diseases in populations and for food scientitsts and food manufacturers to develop new products with optimized properties.

A comparative study on chemical composition and antioxidant activity of ginger (Zingiber officinale) and cumin (Cuminum cyminum).

Abstract: Spices are the building blocks of flavor in foods. This research work was focused on two important spices, i.e., ginger and cumin. Ginger and cumin both are recognized for their antioxidant properties. So, this study was designed to evaluate the chemical composition and antioxidant activity of ginger (Zingiber officinale) and cumin (Cuminum cyminum). The highest yield for volatile oil was obtained by the cumin sample, which was 2.52 +/- 0.11%, while the fresh ginger showed the lowest yield (0.31 +/- 0.08%). The analysis of volatile oils of fresh and dried ginger showed camphene, p-cineole, alpha-terpineol, zingiberene and pentadecanoic acid as major components, while the major components in cumin volatile oil were cuminal, gamma-terpinene and pinocarveol. In nonvolatile extracts the highest yield was obtained by the methanol extract of cumin (4.08 +/- 0.17% w/w), while the n-hexane extract of fresh ginger showed the lowest yield (0.52 +/- 0.03% w/w). Maximum total phenolic contents were observed in the methanol extract of fresh ginger (95.2 mg/g dry extract) followed by the hexane extract of fresh ginger (87.5 mg/g dry extract). The hexane extract of cumin showed the lowest total phenolic content (10.6 mg/g dry extract). The DPPH method showed the highest antioxidant activity for cumin essential oil (85.44 +/- 0.50%) followed by dried ginger essential oil (83.87 +/- 0.50%) and fresh ginger essential oil (83.03 +/- 0.54%). The FRAP of essential oils showed almost comparative results with DPPH. Cumin essential oil was found best in reducing Fe(3+) ions, followed by dried and fresh ginger. Our results suggest that both ginger and cumin can be used as potential sources of natural antioxidants in foods.

Cellular antioxidant activity of common vegetables.

Abstract: The measurement of antioxidant activity using biologically relevant assays is important to screen fruits, vegetables, natural products, and dietary supplements for potential health benefits. The cellular antioxidant activity (CAA) assay quantifies antioxidant activity using a cell culture model and was developed to meet the need for a more biologically representative method than the popular chemistry antioxidant capacity measures. The objective of the study was to determine the CAA, total phenolic contents, and oxygen radical absorbance capacity (ORAC) values of 27 vegetables commonly consumed in the United States. Beets, broccoli, and red pepper had the highest CAA values, whereas cucumber had the lowest. CAA values were significantly correlated to total phenolic content. Potatoes were found to be the largest contributors of vegetable phenolics and CAA to the American diet. Increased fruit and vegetable consumption is an effective strategy to increase antioxidant intake and decrease oxidative stress and may lead to reduced risk of developing chronic diseases, such as cancer and cardiovascular disease.

Effect of different cooking methods on color, phytochemical concentration, and antioxidant capacity of raw and frozen brassica vegetables.

Abstract: This study evaluated the effect of common cooking practices (i.e., boiling, microwaving, and basket and oven steaming) on the phytochemical content (carotenoids, chlorophylls, glucosinolates, polyphenols, and ascorbic acid), total antioxidant capacity (TAC), and color changes of three generally consumed Brassica vegetables analyzed fresh and frozen. Among cooking procedures, boiling determined an increase of fresh broccoli carotenoids and fresh Brussels sprout polyphenols, whereas a decrease of almost all other phytochemicals in fresh and frozen samples was observed. Steaming procedures determined a release of polyphenols in both fresh and frozen samples. Microwaving was the best cooking method for maintaining the color of both fresh and frozen vegetables and obtaining a good retention of glucosinolates. During all cooking procedures, ascorbic acid was lost in great amount from all vegetables. Chlorophylls were more stable in frozen samples than in fresh ones, even though steaming methods were able to bet...

Green tea flavan-3-ols: colonic degradation and urinary excretion of catabolites by humans.

Abstract: Following the ingestion of green tea, substantial quantities of flavan-3-ols pass from the small to the large intestine (Stalmach et al. Mol. Nutr. Food Res. 2009, 53, S44-S53; Mol. Nutr. Food Res. 2009, doi: 10.1002/mnfr.200900194). To investigate the fate of the flavan-3-ols entering the large intestine, where they are subjected to the action of the colonic microflora, (-)-epicatechin, (-)-epigallocatechin, and (-)-epigallocatechin-3-O-gallate were incubated in vitro with fecal slurries and the production of phenolic acid catabolites was determined by GC-MS. In addition, urinary excretion of phenolic catabolites was investigated over a 24 h period after ingestion of either green tea or water by healthy volunteers with a functioning colon. The green tea was also fed to ileostomists, and 0-24 h urinary excretion of phenolic acid catabolites was monitored. Pathways are proposed for the degradation of green tea flavan-3-ols in the colon and further catabolism of phenolic compounds passing into the circulatory system from the large intestine, prior to urinary excretion in quantities corresponding to ca. 40% of intake compared with ca. 8% absorption of flavan-3-ol methyl, glucuronide, and sulfate metabolites in the small intestine. The data obtained point to the importance of the colonic microflora in the overall bioavailability and potential bioactivity of dietary flavonoids.

Phenolic Acids and Flavonoids in Nonfermented and Fermented Red Sorghum (Sorghum bicolor (L.) Moench)

Abstract: This study aimed to identify phenolic acids and flavonoids in the red sorghum variety PAN 3860 and to determine changes in their concentrations during fermentation with lactobacilli. Sorghum sourdoughs fermented with two binary strain combinations, Lactobacillus plantarum and Lactobacillus casei or Lactobacillus fermentum and Lactobacillus reuteri , were compared to chemically acidified controls. Four glycerol esters were tentatively identified, caffeoylglycerol, dicaffeoylglycerol, coumaroyl-caffeoylglycerol, and coumaroyl-feruloylglycerol, that have previously not been detected in sorghum. Chemical acidification resulted in hydrolysis of phenolic acid esters and flavonoid glucosides. During lactic fermentation, phenolic acids, phenolic acid esters, and flavonoid glucosides were metabolized. Analysis of ferulic acid, caffeic acid, and naringenin-glucoside contents in single-strain cultures of lactobacilli demonstrated that glucosidase, phenolic acid reductase, and phenolic acid decarboxylase activities contributed to polyphenol metabolism. This study demonstrates that microbial fermentation of sorghum affects the content of polyphenols and can influence the nutritional value and antimicrobial activity of sorghum.

Relationship of granule size distribution and amylopectin structure with pasting, thermal, and retrogradation properties in wheat starch.

Abstract: Starches separated from 18 Indian wheat varieties were evaluated to see relationship of granule size distribution and amylopectin structure with pasting, thermal, and retrogradation properties. Average diameter of A-, B-, and C-granules among different starches varied between 23.0 and 28.5, 10.0 and 12.0, and 2.3 and 2.7 μm, respectively. Amylopectin chain length distribution varied significantly, short length chains (DP 6−12) and long length chains (DP > 24) ranged between 44.5 and 52.4% and 3.7 and 6.5%, respectively, whereas amylose content ranged between 18.2 and 28.8%. Short length chains of amylopectin had inverse relationship with starch gelatinization temperatures To, Tp, and Tc. Starches with higher crystallinity had higher enthalpy of gelatinization and lower swelling power. Paste characteristics were mainly dependent upon granule type and all pasting parameters except pasting temperature, showed significant positive correlations with A-granules and negative with the proportion of B- and C-granule.

Curcumin nanoparticles improve the physicochemical properties of curcumin and effectively enhance its antioxidant and antihepatoma activities

Abstract: Curcumin (CUR), a natural polyphenol isolated from tumeric (Curcuma longa), has been documented to possess antioxidant and anticancer activities. Unfortunately, the compound has poor aqueous solubility, which results in poor bioavailability following high doses by oral administration. To improve the solubility of CUR, we developed a novel curcumin nanoparticle system (CURN) and investigated its physicochemical properties as well as its enhanced dissolution mechanism. Our results indicated that CURN improved the physicochemical properties of CUR, including a reduction in particle size and the formation of an amorphous state with hydrogen bonding, both of which increased the drug release of the compound. Moreover, in vitro studies indicated that CURN significantly enhanced the antioxidant and antihepatoma activities of CUR (P < 0.05). Consequently, we suggest that CURN can be used to reduce the dosage of CUR and improve its bioavailability and merits further investigation for therapeutic applications.

Bioavailability of Anthocyanins and Ellagitannins Following Consumption of Raspberries by Healthy Humans and Subjects with an Ileostomy

Abstract: The fate of anthocyanins, ellagic acid, and ellagitannins was studied following the consumption of 300 g of raspberries by healthy human volunteers and subjects with an ileostomy. Postingestion plasma and urine from the former and ileal fluid and urine from the latter group were collected and analyzed by HPLC-PDA-MS(2). Plasma from the healthy volunteers did not contain detectable quantities of either the native raspberry polyphenolics or their metabolites. The three main raspberry anthocyanins were excreted in urine in both healthy and ileostomy volunteers 0-7 h after ingestion, in quantities corresponding to <0.1% of intake. This indicates a low level of absorption in the small intestine. With ileostomy volunteers 40% of anthocyanins and 23% of the ellagitannin sanguiin H-6 were recovered in ileal fluid with the main excretion period being the first 4 h after raspberry consumption. The recovery of ellagic acid in ileal fluid was 241%, indicating hydrolysis of ellagitannins in the stomach and/or the small intestine. Urinary excretion of ellagic acid and an ellagic acid-O-glucuronide was <1% of intake. No intact or conjugated forms of ellagitannins were detected in urine from either healthy subjects or ileostomy volunteers. However, in healthy subjects, but not the ileostomists, ellagitannins were catabolized with the appearance of urolithin A-O-glucuronide, two of its isomers, and urolithin B-O-glucuronide in urine collected 7-48 h after raspberry consumption. There was marked variation in the urolithin profile of individual volunteers, indicating differences in the colonic microflora responsible for ellagitannin degradation.

Safety and pharmacokinetics of a solid lipid curcumin particle formulation in osteosarcoma patients and healthy volunteers.

Abstract: Curcumin is the lipid-soluble antioxidant compound obtained from the rhizome of Curcuma longa Linn, also known as turmeric. Curcumin targets multiple chemotherapeutic and inflammatory pathways and has demonstrated safety and tolerability in humans, supporting its potential as a therapeutic agent; however, the clinical literature lacks conclusive evidence supporting its use as a therapeutic agent due to its low bioavailability in humans. The purpose of this study was to quantify plasma levels of free curcumin after dosing of a solid lipid curcumin particle (SLCP) formulation versus unformulated curcumin in healthy volunteers and to determine its tolerability and dose−plasma concentration relationship in late-stage osteosarcoma patients. Doses of 2, 3, and 4 g of SLCP were evaluated in 11 patients with osteosarcoma. Plasma curcumin levels were measured using a validated high-performance liquid chromatography method. The limit of detection of the assay was 1 ng/mL of curcumin. In healthy subjects, the mean p...

HPLC-MS analysis of proanthocyanidin oligomers and other phenolics in 15 strawberry cultivars.

Abstract: The phenolic compounds of 15 strawberry cultivars grown in Spain were analyzed and quantified: anthocyanins (20.2−47.4 mg/100 g of fw) (cyanidin 3-glucoside and pelargonidin 3-glucoside, 3-rutinosi...

Evaluating the quality of protein from hemp seed (Cannabis sativa L.) products through the use of the protein digestibility-corrected amino acid score method.

Abstract: The macronutrient composition and the quality of protein of hemp seed and products derived from hemp seed grown in Western Canada were determined. Thirty samples of hemp products (minimum 500 g), including whole hemp seed, hemp seed meal from cold-press expelling, dehulled, or shelled, hemp seed and hemp seed hulls, were obtained from commercial sources. Proximate analysis, including crude protein (% CP), crude fat (% fat) and fiber, as well as full amino acid profiles, were determined for all samples. Protein digestibility-corrected amino acid score (PDCAAS) measurements, using a rat bioassay for protein digestibility and the FAO/WHO amino acid requirement of children (2−5 years of age) as reference, were conducted on subsets of hemp products. Mean (±SD) percentage CP and fat were 24.0(2.1) and 30.4(2.7) for whole hemp seed, 40.7(8.8) and 10.2(2.1) for hemp seed meal, and 35.9(3.6) and 46.7(5.0) for dehulled hemp seed. The percentage protein digestibility and PDCAAS values were 84.1−86.2 and 49−53% for w...

Relationship Between the Antioxidant Capacity and Effect of Rosemary (Rosmarinus Officinalis L.) Polyphenols on Membrane Phospholipid Order

Abstract: The antioxidant activity of rosemary (Rosmarinus officinalis L.) extracts is mainly due to phenolic abietane diterpenes and phenolic acids such as rosmarinic acid. In this study a comprehensive characterization of non-water-soluble and water-soluble extracts from rosemary was achieved by liquid chromatography coupled to electrospray and mass spectrometry. The antioxidant activity of these extracts and their respective major compounds (carnosic acid, carnosol, rosmadial, genkwanin, and rosmarinic acid) was analyzed and compared by using different in vitro systems. Whereas rosmarinic acid, carnosic acid, and carnosol exhibited similar antioxidant activity in a phospholipid membrane-free assay, carnosol behaved as an extremely potent antioxidant in a membrane-based assay (4-6 times stronger than the rest of the compounds). This differential antioxidant behavior suggests that factors other than the radical scavenging capability may be involved. All of the diterpenes induced severe effects on lipid order and packing of phospholipid model membranes. Rosmadial and carnosol decreased the number and/or mobility of water molecules located at the polar head group region of the membrane phospholipids as seen by Laurdan fluorescence spectroscopy. Carnosol also strongly enhanced lipid order at the hydrophobic core of the membrane. These effects throughout the bilayer correlated to the stronger antioxidant capacity of carnosol to inhibit lipid peroxidation. On the contrary, carnosic acid decreased membrane fluidity at deeper regions of the bilayer as measured by bilayer-to-micelle transition assay and self-quenching measurements by using octadecylrhodamine B. These effects may contribute to membrane stabilization and hindrance of radical propagation, which may cooperate with the electron donor ability of rosemary diterpenes in protecting the membranes against oxidative damage.