Principal Fractions Research Articles

Structural and Thermal Characterization of Protein Isolates from Australian Lupin Varieties as Affected by Processing Conditions.

Proteins from the full and defatted flours of L. angustifolius cv Jurien and L. albus cv Murringo were prepared using alkaline extraction and iso-electric precipitation. Isolates were either freeze dried or spray dried or pasteurized at 75 ± 3 °C/5 min before freeze-drying. Various structural properties were investigated to elucidate the varietal and processing-induced effect on molecular and secondary structure. Irrespective of processing, isolated proteins had a similar molecular size, with α-conglutin (412 kDa) and β-conglutin (210 kDa) being principal fractions for the albus and angustifolius variety, respectively. Smaller peptide fragments were observed for the pasteurized and spray dried samples, indicating some degree of processing-induced changes. Furthermore, secondary structure characterization by Fourier-transform-infrared and circular dichroism spectroscopy showed β-sheet and α-helical structure being the dominant structure, respectively. Thermal characterization showed two denaturation peaks corresponding to β-conglutin (Td = 85-89 °C) and α-conglutin (Td = 102-105 °C) fractions. However, the enthalpy values for α-conglutin denaturation were significantly higher for albus species, which corroborates well with higher amounts of heat stable α-conglutin present. Amino acid profile was similar for all samples with limiting sulphur amino acid. In summary, commercial processing conditions did not have a profound effect on the various structural properties of lupin protein isolates, and properties were mainly determined by varietal differences.

Identification of novel anti-inflammatory peptides from bee pollen (Apis mellifera) hydrolysate in lipopolysaccharide-stimulated RAW264.7 macrophages

Bee pollen protein was hydrolyzed using the commercial Alcalase, Flavourzyme and Neutrase enzymes. The Neutrase hydrolysate formed from a 1:1 (v/v) enzyme/substrate ratio (NH1) showed the highest nitric oxide (NO) radical scavenging activity. The NH1 was further separated into five fractions based on molecular weight (MW1–5) and MW1, the smallest weight fraction (< 0.65 kDa), possessed the highest NO inhibitory activity. The effects of NH1 on the production of NO were assessed by incubating with lipopolysaccharide-stimulated RAW264.7 macrophage cells. NO levels from the culture supernatants were determined by the Griess reaction. The results showed that MW1 suppressed the production of pro-inflammatory cytokines including cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), tumor interleukin-6 (IL-6) and necrosis factor transcript expression (TNF-α) in RAW264.7 macrophage cells. Thus, the MW1 fraction was fractionated using reversed-phase high-performance liquid chromatography into six principal fractions (H1–6), where H2, H3 and H4 showed strong NO inhibitory activity. Seven peptide sequences were obtained by quadrupole time-of-flight mass spectrometry, three of which displayed potent anti-inflammatory activity and may be useful ingredients in functional food and pharmaceutical drugs.

Active Essential Oils and Their Components in Use against Neglected Diseases and Arboviruses.

The term neglected diseases refers to a group of infections caused by various classes of pathogens, including protozoa, viruses, bacteria, and helminths, most often affecting impoverished populations without adequate sanitation living in close contact with infectious vectors and domestic animals. The fact that these diseases were historically not considered priorities for pharmaceutical companies made the available treatments options obsolete, precarious, outdated, and in some cases nonexistent. The use of plants for medicinal, religious, and cosmetic purposes has a history dating back to the emergence of humanity. One of the principal fractions of chemical substances found in plants are essential oils (EOs). EOs consist of a mixture of volatile and hydrophobic secondary metabolites with marked odors, composed primarily of terpenes and phenylpropanoids. They have great commercial value and were widely used in traditional medicine, by phytotherapy practitioners, and in public health services for the treatment of several conditions, including neglected diseases. In addition to the recognized cytoprotective and antioxidative activities of many of these compounds, larvicidal, insecticidal, and antiparasitic activities have been associated with the induction of oxidative stress in parasites, increasing levels of nitric oxide in the infected host, reducing parasite resistance to reactive oxygen species, and increasing lipid peroxidation, ultimately leading to serious damage to cell membranes. The hydrophobicity of these compounds also allows them to cross the membranes of parasites as well as the blood-brain barrier, collaborating in combat at the second stage of several of these infections. Based on these considerations, the aim of this review was to present an update of the potential of EOs, their fractions, and their chemical constituents, against some neglected diseases, including American and African trypanosomiasis, leishmaniasis, and arboviruses, specially dengue.

Beetle (Ulomoides dermestoides) fat improves diabetes: effect on liver and pancreatic architecture and on PPARγ expression.

Ulomoides dermestoides is a beetle traditionally consumed to treat diabetes. In this study, we performed a composition analysis of U. dermestoides to obtain the principal fractions, which were used to assess the effect on glycemia, liver and pancreatic architecture, and PPARγ and GLUT4 expression. Normal mice and alloxan-induced diabetic mice were administered fractions of chitin, protein or fat, and the acute hypoglycemic effect was evaluated. A subacute study involving daily administration of these fractions to diabetic mice was also performed over 30 days, after which the liver and pancreas were processed by conventional histological techniques and stained with hematoxylin and eosin to evaluate morphological changes. The most active fraction, the fat fraction, was analyzed by gas chromatography-mass spectrometry (GC-MS), and PPARγ and GLUT4 mRNA expressions were determined in 3T3-L1 adipocytes. The protein and fat fractions exhibited hypoglycemic effects in the acute as well as in the 30-day study. Only the fat fraction led to elevated insulin levels and reduced glycemia, as well as lower intake of water and food. In the liver, we observed recovery of close hepatic cords in the central lobule vein following treatment with the fat fraction, while in the pancreas there was an increased density and percentage of islets and number of cells per islet, suggesting cellular regeneration. The GC-MS analysis of fat revealed three fatty acids as the major components. Finally, increased expression of PPARγ and GLUT4 was observed in 3T3-L1 adipocytes, indicating an antidiabetic effect.

Enzymatic saccharification and liquid state fermentation of hydrothermal pretreated Tunisian Luffa cylindrica (L.) fibers for cellulosic bioethanol production

The main drivers to develop biorefineries are the energetic and environmental crisis. Consequently, bioenergies have become a scientific and industrial trend. In North Africa, especially in Tunisia, Luffa cylindrica (LC) is a promising energy crop providing lignocellulosic biomass for biofuels production. Three principal fractions compose LC biomass, viz.: α-cellulose (45.8 ± 1.3)%, hemicellulose (20.76 ± 0.3)% and lignins (13.15 ± 0.6)%. The hydrothermal pretreatment of LC fibers was carried out at 96 °C for 54 min. After pretreatment, the reducing sugars amount reached 33.55 g/kg. The subsequent enzymatic saccharification was performed during 1 h at a temperature of 60 °C, by means of two commercial enzymes AP2 and SPC. The enzyme AP2 seemed to be more suitable for the enzymatic hydrolysis of pretreated LC fibers by allowing the release of 59.4 g/kg of reducing sugars, which correspond to a reducing sugars recovery about 93.29%. After that, the liquid state fermentation (LSF) was achieved with Saccharomyces cerevisiae strain during 24 h, in sterile and non-sterile conditions at 30 °C, pH 4.8 ± 0.2 and stirring 250 rpm, in order to conclude about the influence of contamination microflora on fermentation efficiency. After the LSF step, 88.66% of reducing sugars were transformed into alcohol with a conversion rate of 1.58% and a volumetric yield about 70% in sterile conditions. Thus, this work confirms that the potential conversion yield of cellulosic bioethanol is 1 Ton (dry matter) of LC fibers to 13.8545 kg (= 3.6599 Gallon) of biofuel.

Optimization of Hydrothermal and Diluted Acid Pretreatments of Tunisian Luffa cylindrica (L.) Fibers for 2G Bioethanol Production through the Cubic Central Composite Experimental Design CCD: Response Surface Methodology.

This paper opens up a new issue dealing with Luffa cylindrica (LC) lignocellulosic biomass recovery in order to produce 2G bioethanol. LC fibers are composed of three principal fractions, namely, α-cellulose (45.80% ± 1.3), hemicelluloses (20.76% ± 0.3), and lignins (13.15% ± 0.6). The optimization of LC fibers hydrothermal and diluted acid pretreatments duration and temperature were achieved through the cubic central composite experimental design CCD. The pretreatments optimization was monitored via the determination of reducing sugars. Then, the 2G bioethanol process feasibility was tested by means of three successive steps, namely, LC fibers hydrothermal pretreatment performed at 96°C during 54 minutes, enzymatic saccharification carried out by means of a commercial enzyme AP2, and the alcoholic fermentation fulfilled with Saccharomyces cerevisiae. LC fibers hydrothermal pretreatment liberated 33.55 g/kg of reducing sugars. Enzymatic hydrolysis allowed achieving 59.4 g/kg of reducing sugars. The conversion yield of reducing sugar to ethanol was 88.66%. After the distillation step, concentration of ethanol was 1.58% with a volumetric yield about 70%.

Fractionation of microbial populations in a PHA accumulating mixed culture and associated PHA content and composition

The uniformity of PHA composition and content across groups of organisms in mixed cultures was considered. An activated sludge microbial community, with an average PHA content of 20wt%, was fractioned by Percoll assisted buoyant density separation. The microbial community in the two principal fractions was characterised using amplicon pyrosequencing. While organisms were common to both fractions, the relative abundances of species were found to be different between the two fractions. The average PHA content in one of the fractions was found to be higher (24wt%) than the other (16wt%); separation was considered to be in part driven by the density difference associated with PHA content, but also by other factors such as cell dimension and cellular morphology. But while differences in PHA content were observed, the PHA composition in both fractions was found to be approximately the same (43–44mol% HV), which shows that distinct groups of microbial populations within mixed cultures may generate PHA with similar average copolymer composition.

Tortilla added with unripe banana and cassava flours: chemical composition and starch digestibility

Tortilla is the main staple food in Mexico. The principal fractions of tortillas are carbohydrates, where starch is the major constituent. Tortillas containing corn dough (600 g/kg) plus unripe banana flour (400 g/kg) (Musa paradisiaca L.) (UBF), and corn dough (500 g/kg) plus cassava flour (500 g/kg) (Mahinot esculenta Crantz) (CF) were analyzed for chemical composition and in vitro starch digestibility, and the glycemic index was also predicted. Protein and dietary fiber content decreased in tortillas added with UBF and CF. Fresh tortilla with UBF had the highest resistant starch (RS) content and with CF the lowest one. An increase in RS content with the storage time was determined in control tortilla and with CF, but tortilla with UBF did not. The predicted glycemic index decreased in stored tortillas. The change in digestible carbohydrates in tortilla with the addition of non-traditional ingredients can be an alternative for people with special nutrition requirements.

Quantum Hall Effect in AlGaAs and Graphite Quantum Dots

Abstract. The 30 nm wide quantum wells on a 4x4 mm2 piece of GaAs/AlGaAs are formed when the layers of GaAs are deposited on AlGaAs films. The two-dimensional density of electrons is 3x1011 cm-2 and the mobility is 32x106 cm2/Vs. In such a sample the Hall resistivity as a function of magnetic field is not a linear function. Hence a suitable theory to understand the Hall effect is formulated. We find that there are phase transitions as a function of temperature. There are lots of fractions of charge which are explained on the basis of spin and orbital angular momentum of the electron. The nano meter size films of graphite also show that the Hall resistivity is non-linear and shows steps as a function of magnetic field. We make an effort to understand the steps in the Hall effect resistivity of graphite with quantum wells formed on the surface. It is found that the fractions are in four categories, (i) the principal fractions which are determined by spin and orbital angular momenta, (ii) the resonances which occur at the difference between two values such as =1-2, (iii) two-particle states which occur at the sum of the two frequencies and (iv) there are clusters of electrons localized in some areas of the sample. The spin in the clusters is polarized so that it becomes NS which is not 1/2 but depends on the number N, of electrons in a cluster.

Investigation of Deformed and Recrystallized Textures in Zirconium

The analysis of deformed and recrystallized zirconium, used in nuclear industry is presented. The main purpose of the present work is to describe and analyze changes in texture, microstructure and misorientation profile, which are observed during a complete thermomechanical treatment. Zirconium samples were channel compressed till various degrees of deformation. The samples were then annealed. In both deformed and recrystallized states, topological maps were measured using the well known EBSD (Electron Backscatter Diffraction) technique. The obtained data were necessary for further analysis which consisted of several approaches: quantification of textures, identification of principal components, volume fractions, misorientations, grain size and IQ histograms. For the misorientation analysis, several parameters have also been tested (ie. correlated misorientation profile, grain average misorientation, kernel, etc.). Based on this complete set of data a scenario is proposed to explain the observed microstructural evolutions.

Thujone‐Rich Fraction of Thuja occidentalis Demonstrates Major Anti‐Cancer Potentials: Evidences from In Vitro Studies on A375 Cells

Crude ethanolic extract of Thuja occidentalis (Fam: Cupressaceae) is used as homeopathic mother tincture (TOΦ) to treat various ailments, particularly moles and tumors, and also used in various other systems of traditional medicine. Anti-proliferative and apoptosis-inducing properties of TOΦ and the thujone-rich fraction (TRF) separated from it have been evaluated for their possible anti-cancer potentials in the malignant melanoma cell line A375. On initial trial by S-diphenyltetrazolium bromide assay, both TOΦ and TRF showed maximum cytotoxic effect on A375 cell line while the other three principal fractions separated by chromatography had negligible or no such effect, because of which only TRF was further characterized and subjected to certain other assays for determining its precise anti-proliferative and apoptotic potentials. TRF was reported to have a molecular formula of C10H16O with a molecular weight of 152. Exposure of TRF of Thuja occidentalis to A375 cells in vitro showed more cytotoxic, anti-proliferative and apoptotic effects as compared with TOΦ, but had minimal growth inhibitory responses when exposed to normal cells (peripheral blood mononuclear cell). Furthermore, both TOΦ and TRF also caused a significant decrease in cell viability, induced inter-nucleosomal DNA fragmentation, mitochondrial transmembrane potential collapse, increase in ROS generation, and release of cytochrome c and caspase-3 activation, all of which are closely related to the induction of apoptosis in A375 cells. Thus, TRF showed and matched all the anti-cancer responses of TOΦ and could be the main bio-active fraction. The use of TOΦ in traditional medicines against tumors has, therefore, a scientific basis.

Investigation of the Possibility for Enzymatic Utlization of Chicken Bones

ABSTRACTA perspective approach is proposed in which ground chicken bones remaining in the poultry slaughterhouses after extracting the meat from them for human food are treated by minimal amounts of purified alkaline protease (Alcalase). Using this process two principal fractions were obtained- soluble protein hydrolysate (SPH) that can be used as component of microbiological cultivation broth media or as a “protein” nutritive additive in the diet of domestic animals and insoluble mainly inorganic fraction (IF) that can find application as fertilizer containing Ca, Mg, and small amounts of P, C, and N or can be used as additive in the diet of hens and other domestic animals. The yields of SPH and IF regarding the quantity of the starting chicken bones were about 22% and 18%, respectively. The process is perspective since: 1. It is energy saving especially when the SPH fraction is used directly for animal feeding without drying; 2. It is not labour consuming; and 3. A waste product is converted into useful substances without any pollution for the environment.

Fuels obtained by thermal cracking of individual and mixed polymers

AbstractUtilization of oils/waxes obtained from thermal cracking of individual LDPE (low density polyethylene), HDPE (high density polyethylene), LLDPE (linear low density polyethylene), PP (polypropylene), or cracking of mixed polymers PP/LDPE (1: 1 mass ratio), HDPE/LDPE/PP (1: 1: 1 mass ratio), HDPE/LDPE/LLDPE/PP (1: 1: 1: 1 mass ratio) for the production of automotive gasolines and diesel fuels is overviewed. Thermal cracking was carried out in a batch reactor at 450°C in the presence of nitrogen. The principal process products, gaseous and liquid hydrocarbon fractions, are similar to the refinery cracking products. Liquid cracking products are unstable due to the olefins content and their chemical composition and their properties strongly depend on the feed composition. Naphtha and diesel fractions were hydrogenated over a Pd/C catalyst. Bromine numbers of hydrogenated fractions decreased to values from 0.02 g to 6.9 g of Br2 per 100 g of the sample. Research octane numbers (RON) before the hydrogenation of naphtha fractions were in the range from 80.5 to 93.4. After the hydrogenation of naphtha fractions, RON decreased to values from 61.0 to 93.6. Diesel indexes (DI) for diesel fractions were in the range from 73.7 to 75.6. After the hydrogenation of diesel fractions, DI increased up to 104.9.

Different chromatin fractions of tomato ( Solanum lycopersicum L.) and related species

Conventional chromosome staining has suggested that more than 75% of the tomato chromosomes are constituted by heterochromatin. In order to determine whether more deeply stained proximal regions are classic heterochromatin, the distributions of C-bands and chromomycin A 3 (CMA) bands, and the prophase condensation patterns, were analysed in tomato. In this and most other species of the tomato clade, the 5S and 45S rDNA sites were also localised. In tomato, CMA banding was similar to C-banding. After conventional staining, all species displayed large condensed heteropycnotic regions that did not correspond to C-bands or CMA bands. Analyses of the CMA banded karyotypes revealed a low heterochromatin content. Around 12–17% of the chromatin of tomato was CMA + and 1/4 to 1/5 of this heterochromatin corresponded to 45S rDNA. In other species, the CMA + heterochromatin showed extensive variation (8–35%), but was never near the values found in the literature for tomato. These data suggest the existence of three principal fractions of chromatin in tomato and related species: the late condensed euchromatin corresponding to the terminal regions of the chromosomes, the precocious condensed euchromatin that occupies the major part of the chromosomes and the constitutive heterochromatin that represents those regions revealed by C-bands.

Seasonal variations in the component structure of the total phosphorus in the bodies of Antarctic amphipods

Using the procedure of sequential multistage acidic hydrolysis at different temperatures, eight fractions of the total phosphorus were separated from the bodies of Antarctic amphipods. The results showed that the variations of the phosphorus concentrations in the principal fractions within the zooplankton organisms are characterized by seasonal variations complying with the periods of the amphipod life cycle. The prospects of these biochemical studies consist in the discovery of new mechanisms explaining some problems not only of seasonal but also of diurnal physiology of plankton organisms.

Effet de la distillation fractionnée sur la composition chimique et l'activité antimicrobienne des huiles essentielles du Myrte (Myrtus communis L.) du Maroc

The essential oil extracted from Moroccan Myrtle and fractions obtained by fractional distillation were analysed by chromatographic methods (GC and GC/MS). Moroccan Myrtle essential oil was found to contain α-pinene (10%), 1,8-cineole (43%) and myrtenyl acetate (25%) as major components. The rectification of Myrtle oil gives four principal fractions. The first was rich in α-pinene (42–54.8%) and 1,8-cineole (27–53.6%), the second fraction in 1,8-cineole (83–95.8%), the third in myrtenyl acetate (36–55%) and 1,8-cineole (12–36%) and the fourth in myrtenyl acetate (62–65%). The fractional distillation improves the quality of essential oil. An antimicrobial activity test carried out with principal fractions of the essential oil showed that the activity was mainly observed in third fraction containing α-terpineol and myrtenol, in particular, and 1,8-cineole.

Fractionation and Characterization of the Monosaccharides from Mesquite Prosopis spp. and Arabic Gum by Normal, Bonded Phase, HPLC

A sensitive and selective assay of galactose, arabinose, and rhamnose is presented for its determination in mesquite and Arabic gums. Gum samples from mesquite and Arabic were fractionated by hydrophobic affinity chromatography, hydrolyzed, and analyzed by normal bonded phase high performance liquid chromatography with refraction index measurement. The assay demonstrated that it was fast and with good linear and high precision response. The column and detector performance showed good retention, selectivity, and efficiency. Based on replicated analysis of standards over a range of 0–13.33 mg/mL, the method is accurate (95–100%), and precise (CV of 3% daily). The results indicated that both gums consist of three principal fractions. The mesquite tears and native showed higher total carbohydrates content (75.73 and 76.26%) in comparison with Arabic gum (61.81%). The saccharides isolated from the Arabic gum contained galactose, arabinose, and rhamnose. Fraction I of Arabic gum showed a higher rhamnose content (7.24%) in comparison with mesquite (0.89%). Only the hydrolyzed fraction I showed the rhamnose content in mesquite. In the fractions, the content of galactose predominating in the Arabic gum was 25.21–26.35% and arabinose in the mesquite gum was 34.43–53.49%.

Fractional distillation effect on the chemical composition of Moroccan myrtle (Myrtus communis L.) essential oils

The essential oil was extracted from Moroccan myrtle and followed by fractional distillation. The fractions obtained were analysed by GC and GC/MS. Moroccan myrtle essential oil contained α-pinene (10%), 1,8-cineole (43%) and myrtenyl acetate (25%) as a major components. The rectification of myrtle oil gives three principal fractions. The first one was rich in α-pinene (42–54.8%) and 1,8-cineole (27–53.6%). The second fraction was dominated by 1,8-cineole (83–95.8%). The third fraction was characterized by myrtenyl acetate (62–65%). Fractional distillation improved the quality of essential oil. Copyright © 2006 John Wiley & Sons, Ltd.

Concordance between results of serum protein electrophoresis of pathological serum by cellulose acetate and capillary zone electrophoresis

We investigated whether the electrophoretic patterns and clinical information derived from the five principal fractions of the Beckman Paragon capillary zone electrophoresis (CZE) 2000 system are comparable to the results obtained by the cellulose acetate electrophoresis (CAE: Olympus AES 320) system. Concordance studies between the results obtained by CAE and CZE were performed on sera from pregnant women and from patients with nephrotic syndrome, acute and chronic inflammatory diseases, cirrhosis, monoclonal and polyclonal gammopathy, and bisalbuminemia. In all subjects except for the pregnant women, the results of CAE and CZE agreed 100% in terms of percent composition for albumin, and α1- and α2-globulins. Concordance for γ-globulin was 92-100% in terms of both percent composition and absolute concentration. Three discordant cases according to the results for β-globulin by CAE and CZE were found in patients with monoclonal gammopathy, who also showed discordant results for γ-globulin. An M-protein spike observed in either the β-globulin or γ-globulin fraction was 100% detected by both CAE and CZE analyses. In another six discordant cases for the β-globulin fraction observed in patients with cirrhosis and polyclonal gammopathy, part of the tail of the β-globulin fraction tended to be measured as γ-globulin by CAE. In three of the four bisalbuminemia cases, the double band of albumin observed by CZE was not detected by CAE. The results show that the electrophoretic patterns and clinical information derived from the five principal fractions of the Beckman Paragon CZE 2000 system are comparable to the results obtained by classical CAE.

Mesquite gum: fractionation and characterization of the gum exuded from Prosopis laevigata obtained from plant tissue culture and from wild trees

The effect of abiotic and biotic stresses in the in vitro gum production from Prosopis laevigata has been studied. The presence of autoclaved microbial biomass (MB) in combination with an incubation temperature of 35 °C induced the greatest gum production. In vitro and in situ gum samples from mesquite were fractionated by hydrophobic affinity chromatography. The results indicated that both gums consist of five principal fractions. The protein content of the fractions varied greatly (0.04–50.05%). For both gums, the protein content in the fractions (F) increased in the following order F2a<F1<F2b<F3a<F3b. The monosaccharide compositions, protein contents and other analyses of whole gums also were performed. The molecular mass distribution was determined by gel permeation chromatography (GPC). Showing the existence of five components varying in molecular mass from 3.5×10 4 to 9.4×10 5.