Comparison of oil and phytosterol levels in germplasm accessions of corn, teosinte, and Job's tears

Seeds of 49 accessions of corn (Zea mays ssp. mays), 9 accessions of teosinte (Zea species that are thought to be ancestors and probable progenitors to corn), and 3 accessions of Job's tears (Coix lacryma), obtained from a germplasm repository, were ground and extracted with hexane. Whole kernel oil yields and levels of four phytonutrients (free phytosterols, fatty acyl phytosterol esters, ferulate phytosterol esters, and gamma-tocopherol) in the oils were measured. Among the seeds tested, oil yields ranged from 2.19 to 4.83 wt %, the levels of ferulate phytosterol esters in the oil ranged from 0.047 to 0.839 wt %, the levels of free phytosterols in the oil ranged from 0.54 to 1.28 wt %, the levels of phytosterol fatty acyl esters in the oil ranged from 0.76 to 3.09 wt %, the levels of total phytosterols in the oil ranged from 1.40 to 4.38 wt %, and the levels of gamma-tocopherol in the oil ranged from 0.023 to 0.127 wt %. In general, higher levels of all three phytosterol classes were observed in seed oils from accessions of Zea mays ssp. mays than in seed oils from accessions of the other taxonomic groups. The highest levels of gamma-tocopherol were observed in teosinte accessions.     

Chemical characterization and anti-inflammatory effect of polysaccharides fractionated from submerge-cultured Antrodia camphorata mycelia

Five polysaccharide fractions (AC-1, AC-2, AC-3, AC-4, and AC-5) were obtained after systemic solvent extractions and precipitations from Antrodia camphorata mycelia with yields of 2.92, 10.38, 1.65, 0.34, and 1.64%, respectively. Gel permeation chromatography (GPC) analysis showed that the distribution of mean molecular mass of the fractionated polysaccharides was in the range of 394-940 kDa. The proximate compositions from each polysaccharide fraction revealed that all fractions belonged to the category of glycoprotein, having ratios of carbohydrate/protein ranging from 0.29 to 10.79 (w/w). Glucose or galactose was the major monosaccharide in all fractions except fraction AC-2, which has a mean molecular mass of 394 kDa with lyxose as the most prominent constituent. In the evaluation of the DPPH* radical scavenging capability, fraction AC-1 and AC-2 polysaccharides showed the better capabilities, around 74.5 and 50.5%, respectively, compared to the reference control of Trolox (87.5%) at a concentration of 1 microM. In testing with macrophage RAW264.7 cells, fraction AC-2 demonstrated a rather potent anti-inflammatory capability. Furthermore, the lipopolysaccharide-induced NO production and the protein expression by the inducible nitric oxide synthase (iNOS) gene were inhibited, respectively, in a dose-dependent (50-200 microg/mL) manner by fraction AC-2 polysaccharide.     

Fractionation and characterization of mushroom dietary fiber (nonstarch polysaccharides) as potential nutraceuticals from sclerotia of Pleurotus tuber-regium (Fries) singer

The nonstarch polysaccharides (NSPs) in the total dietary fiber (TDF) from the sclerotia of Pleurotus tuber-regium (tiger milk mushroom) were fractionated by the sequential use of chemical solvents. About half of the TDF was solubilized and two major alkali-soluble fractions (1 and 4 N sodium hydroxide) that contained 126 and 293 g/kg TDF were obtained. Sugar analysis and infrared spectroscopy indicated that the NSPs in these alkali-soluble fractions were mainly beta-glucans and chitin. These alkali-soluble NSPs were further purified by anion-exchange chromatography followed by gel permeation chromatographic separation. Methylation analysis revealed that these purified glucans were highly branched and contained a mixture of sugar linkages of beta-1,3, beta-1,6, and beta-1,4. The potential use of these sclerotial beta-glucans as nutraceuticals was discussed.     

Characterization of nonstarch polysaccharides content from different edible organs of some vegetables, determined by GC and HPLC: comparative study

Content and composition of dietary fiber as nonstarch polysaccharides (NSP) was determined in vegetables belonging to different types of edible organs, using GC and HPLC. Samples analyzed were subterranean organs (radish and leek), leaves (celery, swiss chard, and lettuce), stalks (celery, swiss chard, and asparagus), inflorescence (broccoli), and fruits (tomato, green pepper, and marrow). The results indicate that though the monomeric profile is similar in all these samples quantitative differences were found for neutral sugars and uronic acids among samples of the same type of vegetal organ. The NSP values determined using CG method were in good agreement with HPLC method (R(2) = 0.9005). However, arabinose, mannose, and galactose plus rhamnose are more influenced by the analytical method used than the rest of the monomers in nearly all the samples analyzed. Final values of NSP depend on the method used in celery stalks, broccoli, and green pepper.     

Fractional and structural characterization of lignins isolated by alkali and alkaline peroxide from barley straw.

A sequential treatment of dewaxed barley straw with sodium hydroxide, different concentrations of hydrogen peroxide, and potassium hydroxide/sodium borate degraded various proportions of the original lignin and solubilized different amounts of the original hemicelluloses. The isolated lignin fractions were subjected to comprehensive structural characterization by UV, FT-IR, and (13)C NMR spectroscopy, and their chemical compositions were analyzed by alkaline nitrobenzene oxidation. All of the lignin fractions were typical of grass lignins and had weight-average molecular weights between 1750 and 2190. It was found that the peroxide treatment at low concentrations (< or =2.0%) resulted in a slight increase in the amount of carboxyl groups, whereas the treatment at a relatively high concentration of alkaline peroxide, such as at 3.0% H(2)O(2), led to a noticeable oxidation of the lignins, as shown by an increase of carboxyl groups. Moreover, the results obtained indicated that the successive treatments with alkali and alkaline peroxide under the conditions used did not significantly affect the beta-O-4 structures of lignins. Substantial amounts of etherified ferulic acids were cleaved by the sequential treatments with alkaline peroxide, as shown in the (13)C NMR spectra. The results underscore the structural differences between alkali- and alkaline peroxide-soluble lignins from barley straw.     

Physicochemical and structural characterization of alkali soluble lignins from oil palm trunk and empty fruit-bunch fibers.

Six alkali soluble lignin fractions were extracted from the cell wall materials of oil palm trunk and empty fruit-bunch (EFB) fibers with 5% NaOH, 10% NaOH, and 24% KOH/2% H(3)BO(3). All of the lignin fractions contained rather low amounts of associated neutral sugars (0.8-1.2%) and uronic acids (1.1-2.0%). The lignin fractions isolated with 5% NaOH from the lignified palm trunk and EFB fibers gave a relatively higher degree of polymerization as shown by weight-average molecular weights ranging between 2620 and 2840, whereas the lignin fractions isolated with 10% NaOH and 24% KOH/2% H(3)BO(3) from the partially delignified palm trunk and EFB fibers showed a relatively lower degree of polymerization, as shown by weight-average molecular weights ranging between 1750 and 1980. The results obtained by alkaline nitrobenzene oxidation showed that all of the lignin preparations contained a high proportion of noncondensed syringyl units with small amounts of noncondensed guaiacyl and fewer p-hydroxyphenyl units. The lignin fraction extracted with 5% NaOH from the lignified EFB fiber was mainly composed of beta-O-4 ether-linked units. Small amounts of 5-5', beta-5, and beta-beta' carbon-carbon linkages were also found to be present between the lignin structural units. Further studies showed that uronic, p-hydroxybenzoic, and ferulic acids in the cell walls of palm fibers were esterified to lignin.     

碱提花生粕水溶性多糖工艺研究

为开发提取花生粕多糖,该文通过五元二次旋转正交设计,研究了液料比、温度、碱浓度、时间和提取次数等工艺因素对碱提花生粕中多糖得率的影响,用SAS8.1中响应面分析程序RSREG分析得到了3个因素的回归方程.结果表明,所得方程达显著水平,拟合情况良好.通过对回归方程进行局部寻优分析,得到碱提花生多糖的最佳工艺条件为:液料比34:1,提取温度88℃,碱浓度0.68 mol/L,时间2.4 h,提取次数1次,对应预测得率为9.78%,验证值为9.79%.     

Isolation and characterization of Thiobacillus from alkali soils

Alkali soils are poor in sulphur-oxidizing bacteria. By appropriate enrichment, two bacterial strains resembling Thiobacillus thiooxidans and T. novellus have been isolated from an alkali soil. The strain of T. novellus possesses characteristics which make it suitable in reclamation of alkali soils by sulphur amendment.     

Evaluation of mushroom dietary fiber (nonstarch polysaccharides) from sclerotia of Pleurotus tuber-regium (Fries) singer as a potential antitumor agent

Mushroom dietary fiber or nonstarch polysaccharides (NSPs) that were soluble in hot alkali and belonged to the beta-glucan type were isolated from the sclerotia of an edible mushroom, Pleurotus tuber-regium. The mushroom NSPs were further separated into a number of fractions [hot alkali extracts (HAEs)] with weight-average molecular weights (M(w)) ranging from 1 x 10(4) to 42.2 x 10(4). The HAE fractions [with M(w) of (5.8-17.1) x 10(4)] administered intraperitoneally at a dose of 20 mg/kg of body weight to BALB/c mice implanted with solid tumor Sarcoma 180 were found to be effective in inhibiting tumor proliferation with an inhibition ratio of > or =50%. In vitro experiments using human tumor cell lines HL-60 and HepG2 had shown that HAE fractions with M(w) of (5.8-42.2) x 10(4) also had antiproliferative activity at three different concentrations (50, 100, and 200 microg/mL) toward the tumor cell lines tested. All HAE fractions did not inhibit the growth of a normal kidney cell line (Vero) from monkey. It is therefore postulated that the antitumoral effect of NSPs from the sclerotia of P. tuber-regium is probably host-mediated and cytocidal.     

Evaluation of nonstarch polysaccharides and oligosaccharide content of different soybean varieties (Glycine max) by near-infrared spectroscopy and proteomics

A total of 832 samples of soybeans were screened by near-infrared (NIR) reflectance spectroscopy, to identify soybean samples with a lower content of oligosaccharides and nonstarch polysaccharides (NSP). Of these, 38 samples were identified on the basis of variation in protein content and agronomic value and submitted to high-resolution NIR spectroscopy. On the basis of the NIR data, 12 samples were further selected for chromatographic characterization of carbohydrate composition (mono-, di-, and oligosaccharides and NSP). Their soluble proteins were separated by two-dimensional gel electrophoresis (2DE). Using partial least-squares regression (PLSR), it was possible to predict the content of total NSP from the high-resolution NIR spectra, suggesting that NIR is a suitable and rapid nondestructive method to determine carbohydrate composition in soybeans. The 2DE analyses showed varying intensities of several proteins, including the glycinin G1 precursor. PLSR analysis showed a negative correlation between this protein and insoluble NSP and total uronic acid (UA).     

Chemical characterization of oak heartwood from Spanish forests of Quercus pyrenaica (Wild.). Ellagitannins, low molecular weight phenolic, and volatile compounds

The need for new sources of quality wood supply for cooperage has led to looking into the possibility of utilizing Quercus pyrenaica Wild. oak, a species native to the Iberian peninsula, as an alternative to other European (Quercus robur and Qurecus petraea) and American (Quercus alba) oaks. The low molecular weight phenolic composition, ellagitannins, and volatile compounds (including a wide range of compound families such as volatile phenols, furanic compounds, lactones, phenyl ketones, other lignin-derived compounds, and volatile compounds related to off-flavors) of green heartwood from Spanish forest regions were studied by HPLC and GC, in order to know its enological characteristics. The chemical composition of Q. pyrenaica is similar to that of other species commonly used in cooperage to make barrels, showing only quantitative differences that were more significant with respect to American than to French species. The four provenance regions studied showed similar chemical composition, with high variability among individuals, often higher than the variability among regions of provenance, but in line with that described in other European and American oak woods. Therefore, this species must be considered to be suitable for aging wine.     

Chemical characterization of the high molecular weight material extracted with hot water from green and roasted arabica coffee

The polysaccharides present in coffee infusions are known to contribute to the organoleptic characteristics of the drink, such as the creamy sensation perceived in the mouth known as "body", the release of aroma substances, and the stability of espresso coffee foam. To increase the knowledge about the origin, composition, and structure of the polysaccharide fraction, the high molecular weight material (HMWM) was extracted with hot water from two green and roasted ground arabica coffees: Costa Rica (wet processed) and Brazil (dry processed). The polysaccharides present in the green coffees HMWM were arabinogalactans (62%), galactomannans (24%), and glucans, and those found in roasted coffees were galactomannans (69%) and arabinogalactans (28%). The polysaccharides of the HMWM of the roasted coffees were less branched than those of the green coffees. The major green coffee proteins had molecular weights of 58 and 38 kDa, and the 58 kDa protein had two subunits, of 38 and 20 kDa, possibly linked by disulfide bonds. The protein fraction obtained from roasted coffees had only a defined band with < or =14 kDa and a diffuse band with >200 kDa. The majority of the galactomannans were precipitated with solutions of 50% ethanol, and the size-exclusion chromatography of the roasted fractions showed coelution of polysaccharides, proteins, phenolics, and brown compounds. The use of strong hydrogen and hydrophobic dissociation conditions allowed us to conclude that the phenolics and brown compounds were linked by covalent bonds to the polymeric material.     

Content and molecular weight of extractable beta-glucan in American and Swedish oat samples

beta-(1-->3),(1-->4)-D-Glucan (beta-glucan) was extracted from 93 Swedish and 41 American oat samples using hot water containing CaCl(2) and thermostable alpha-amylase. The samples showed a large variation in both the content of extractable beta-glucan (0.76-3.68%) and the average molecular weight ((1.25-1.78) x 10(6) g mol(-1)). An analysis of the variance of beta-glucan content and the molecular weight of Swedish oat samples grown in 2000 and 2001 was done with cultivar and harvest year as factors. It showed that the extractable beta-glucan content was a heritable trait whereas molecular weight depended more on environmental factors. The American oat samples had a higher average content of extractable beta-glucan (2.24%) and a somewhat higher average molecular weight (1.58 x 10(6) g mol(-1)) than the Swedish oat samples (1.43% and 1.49 x 10(6) g mol(-1)).     

Purification and structural characterization of LTP1 polypeptides from beer

We report on the purification of lipid transfer proteins (LTP) from barley seeds and beer with the aim of investigating the chemical modifications that occur during the brewing process. In seeds, the well-known LTP of 9 kDa (LTP1) has been found together with a second form named LTPb that displays comparable amino acid composition but was not fully sequenced. These two forms have been recovered in beer with marked chemical modifications including disulfide bond reduction and rearrangement and especially glycation by Maillard reaction. The glycation is heterogeneous with variable amounts of hexose units bound to LTPs. Circular dichroism shows that glycated LTP1 having all their disulfide bridges reduced are totally unfolded. These results provide a first basis for understanding how barley LTPs become foam-promoting agents during the malting and brewing process.     

Structural characterization of oligosaccharides and polysaccharides from apple juices produced by enzymatic pomace liquefaction

Eight apple pomace liquefaction juices were produced to characterize soluble cell wall material released by the action of pectolytic and cellulolytic enzyme preparations. Very high colloid values from 9.7 to 19.6 g/L were recovered from the juices by ethanol precipitation. The crude polysaccharides consisted mainly of galacturonic acid (49-64 mol %), arabinose (14-23 mol %), galactose (6-15 mol %), and minor amounts of rhamnose, xylose, and glucose. Separation of the polysaccharides by anion-exchange chromatography yielded one neutral, one slightly acidic, and one acidic polymer accounting for 60% of total colloids. Preparative size exclusion chromatography of the acidic fractions resulted in four polymers of different molecular weights and different sugar compositions. Among them, high molecular weight arabinans and rhamnogalacturonans as well as oligomeric fractions consisting of only galacturonic acid could be found. Linkage studies were performed on neutral fractions from anion-exchange chromatography and size exclusion chromatography. They revealed highly branched arabinans, xyloglucans, and mainly type I arabinogalactans.     

Chemical characterization of Klason lignin preparations from plant-based foods

To analyze the accuracy of the Klason lignin method as applied for the determination of lignin contents in plant based-food products, Klason lignin preparations from curly kale, pears, whole wheat grains, and corn bran were chemically characterized. Characterization included routine ash and protein determinations and the extraction of fat/waxes as well as cutin/suberin depolymerization and extraction of the liberated monomers. Fat/wax and cutin/suberin amounts in the Klason lignin preparations were determined gravimetrically, and their compositions were analyzed by using GC-MS. Typical fat, wax, and cutin (and suberin) constituents such as saturated and unsaturated fatty acids, hydroxy and/or epoxy fatty acids, and phenolic acids were identified in all samples, whereas the detection of long-chain hydrocarbons, alcohols, and ketones, sterols, stanols, and dioic acids was dependent on the sample analyzed. Estimation of the contribution of non-lignin compounds to the Klason lignin contents reduced the noncorrected Klason lignin contents of the insoluble fibers from 28.7% (kale), 22.8% (pear), 14.8% (wheat), and 9.9% (corn) to maximum lignin contents of 6.5% (kale), 16.4% (pear), 4.9% (wheat), and 2.3% (corn). These data demonstrate that certain commonly used statements such as "cereal brans are highly lignified" need to be revised.     

Synthesis and structural characterization of oaklin-catechins

Condensation reactions of procyanidin dimer B4 with two representative oak wood cinnamic aldehydes (coniferaldehyde and sinapaldehyde) were conducted in winelike model solutions. Coniferaldehyde led to the formation of guaiacylcatechin-pyrylium-catechin (GCP-catechin, 737 m/z), whereas sinapaldehyde led to the formation of syringylcatechin-pyrylium-catechin (SCP-catechin, 767 m/z). The former was also structurally characterized by 1D and 2D NMR, allowing an elucidation of the formation mechanism of these oaklin-catechin adducts and demonstrating the importance of procyanidins in the formation of colored compounds through the reaction with cinnamic aldehydes extracted from oaks during storage.     

Almond allergens: molecular characterization, detection, and clinical relevance

Almond ( Prunus dulcis ) has been widely used in all sorts of food products (bakery, pastry, snacks), mostly due to its pleasant flavor and health benefits. However, it is also classified as a potential allergenic seed known to be responsible for triggering several mild to life-threatening immune reactions in sensitized and allergic individuals. Presently, eight groups of allergenic proteins have been identified and characterized in almond, namely, PR-10 (Pru du 1), TLP (Pru du 2), prolamins (Pru du 2S albumin, Pru du 3), profilins (Pru du 4), 60sRP (Pru du 5), and cupin (Pru du 6, Pru du γ-conglutin), although only a few of them have been tested for reactivity with almond-allergic sera. To protect sensitized individuals, labeling regulations have been implemented for foods containing potential allergenic ingredients, impelling the development of adequate analytical methods. This work aims to present an updated and critical overview of the molecular characterization and clinical relevance of almond allergens, as well as review the main methodologies used to detect and quantitate food allergens with special emphasis on almond.     

Determination of the molecular and structural characteristics of okenia, mango, and banana starches

Starches were isolated from nonconventional sources (banana, mango, and okenia) and their characteristics were examined using polarized light microscopy, X-ray diffraction pattern, Fourier transform infrared (FTIR) spectroscopy, and differential scanning calorimetry (DSC). Banana starch granules were of an ellipsoidal shape with size between approximately 8 and 20 microm; okenia had the smallest granule size, between approximately 2 and 5 microm. The three starches showed the Maltese cross, indicative of an intact granule structure. Okenia and mango starches had the A-type X-ray diffraction pattern, common to native cereal starches, whereas banana starch showed a mixture between A- and B-type pattern. Banana starch had the highest temperature (77.6 degrees C) and enthalpy (23.4 J/g) of gelatinization in excess water conditions; okenia had the lowest temperature (71.2 degrees C) and enthalpy (15 J/g), which may be related to the X-ray diffraction pattern and its small granule size. Both the okenia and mango starches had a higher molar mass and gyration radius than banana starch, which may be related to the differences determined in their crystalline structures.     

Chemical characterization and decomposition of organic matter from two contrasting grassland soil profiles

Particle size fractions of soils from the surface 6 cm of two adjacent grassland plots which, as a result of different fertilizer treatments since 1897, have either a mor or a mull humus form were analysed using solid-state ¹³C nuclear magnetic resonance spectroscopy and fractionation of organic N by steam distillation. In the mor humus soil, which had received 180 kg (NH⁴)²SO⁴ ha^?1 annually and was pH 4.3, there was more C and N in the larger particle size fractions than in the mull humus soil (pH 5.8). The NMR spectra of correspondingly sized soil fractions were similar for both soils. The intensities of NMR signals between 0 and 40 ppm (alkyl-C) and between 160 and 200 ppm (carbonyl-C) increased with decreasing particle size. The intensities of the NMR signals between 60 and 90 ppm (0-alkyl-C) and between 90 and 110 ppm (acetal- and ketal-C) decreased with increasing particle size. Comparison of the NMR spectra of the >2000 um fractions from both soils with those of dried grass litter from the same plots indicated the exclusive plant origin of the C in the largest size fraction of the soils. NMR resonances between 40 and 60 ppm were attributed to alkyl-amino-C because their intensities agreed with the amino-N determinations obtained during organic N fractionation. During incubation in soil microcosms, the larger sized fractions decomposed more rapidly than the smaller fractions. However, all the correspondingly sized particle fractions from the two soils decomposed at the same rate except the >2000 pm fractions. The largest size fraction from the mor humus soil decomposed faster than that from the mull humus soil. This difference in decomposition rate could not be attributed to differences in the chemical composition of the >2000 pm fraction.