Evaluation of the addition of ascorbic acid to the ration of cultivated Piaractus mesopotamicus (Characidae) on the infrapopulation of Anacanthorus penilabiatus (Monogenea)

Sixty Piaractus mesopotamicus Holmberg, 1887 (pacu) fry fed a diet containing 0, 50, 100 and 200 mg ascorbic acid/kg dry feed were studied to evaluate the effect on parasitic infestation by the monogenean Anacanthorus penilabiatus Boeger, Husak and Martins, 1995 (Monogenea: Dactylogyridae) for a period of 24 weeks. The temperature of the aquaria was measured daily and remained between 28 and 31oC. At the beginning of the experiment, fish showed 6.15 ± 0.33 cm standard length and 8.64 ± 1.62 g average body weight. A sample of fish was examined and showed 43 ± 17 monogeneans per fish. At the end of the experiment, the gills of control and vitamin C-treated fish were collected for parasite counts. Control fish had 42.5 parasites per fish, a significantly higher number (P<0.05) when compared with fish fed vitamin C, that showed 16.5 parasites per fish. Ascorbic acid fortification in the food promoted an increase in fish resistance to parasites. It is suggested that an optimum level of 139 mg/kg vitamin C supplementation either elicited better nutritional conditions by stimulating the appetite of the fish or improved the immune response.

Effect of addition of different hydrocolloids on pasting, thermal, and rheological properties of cassava starch

Starches and gums are hydrocolloids frequently used in food systems to provide proper texture, moisture, and water mobility. Starch-gum interaction in food systems can change the starch granule swelling and its gelatinization and rheological properties. In this study, the effect of the addition of xanthan gum (XG), sodium carboxymethyl cellulose (SCMC), and carrageenan (CAR) at the concentrations of the 0.15, 0.25, 0.35 and 0.45% (w/v) on the pasting, thermal, and rheological properties of cassava starch was studied. The swelling power (SP) and the scanning electron microscopy (SEM) of the starch gels were also evaluated. The results obtained showed that xanthan gum (XG) had a strong interaction with the cassava starch penetrating between starch granules causing increase in pasting viscosities, SP, storage and loss (G', and G", respectively) modulus and reduction in the setback of the starch; sodium carboxymethyl cellulose (SCMC) greatly increased the pasting viscosities, the SP, and the storage and loss (G', and G", respectively) modulus of the starch-mixtures, mainly due to its greater capacity to hold water and not due to the interaction with cassava starch. Carrageenan (CAR) did not change any of the starch properties since there was no interaction between this gum and cassava starch at the concentrations used.

Influence of the addition of lupine protein isolate on the protein and technological characteristics of dough and fresh bread with added Brea Gum

The effect of protein lupine isolate (LI) and addition of brea gum (BG) on a basic bread formulation is described. The major objective of this research was to evaluate the influence of the addition of LI on the quality and quantity of the proteins of fresh bread with BG. Protein quality was determinate by the Chemical Score method corrected for protein digestibility (CSCD%). The bread dough characteristics were determined by farinograph and alveograph. Fresh bread characterization was performed by measuring the physical parameters and evaluating the crumb structure. The effect of LI and BG on available lysine, the loss of available lysine ratio, and the chemical composition of the breads were also determined. The addition of LI on the bread formulation improved the protein content and the CSCD% of lysine. The dough with LI was less resistant to prolonged kneading and less manageable. With BG addition, the dough became stickier. The quality of fresh bread was affected by the addition of LI: the fresh bread had lower specific volume and more heterogeneous crumbs than that of the control group. The addition of BG did not influence the quality of the bread made with the mixed flour, but it had a positive effect on the loss of available lysine.

Effect of the addition of wheat fiber and partial pork back fat on the chemical composition, texture and sensory property of low-fat bologna sausage containing inulin and oat fiber

The objective of this work was to study the effect of adding wheat fiber and partial pork back fat on the quality characteristics of bologna sausage. The compound central rotating design was used with treatments containing fixed levels of inulin (5%) and oat fiber (1%) and variable levels of wheat fiber (0-4%) and pork back fat (0-10%). The pH and protein were similar in all the treatments, the fat was lower than the control treatment and the moisture content was higher than the control treatment (CF) without fibers. The wheat fiber increased the hardness and reduced cohesiveness and scores were given for overall impression. We found that it was possible to prepare low-fat bologna sausage with the addition of 6.58% fiber (5% inulin, 1% oat fiber and 0.58% wheat fiber), whilst retaining good sensory acceptability, thus reducing the pork back fat levels by between 25 and 42.75%.

Addition of anacardic acid as antioxidants in broiler chicken mortadella

AbstractThe effect of anacardic acid on lipid stability and coloration of chicken mortadella was investigated. Antioxidants were added to chicken mortadellas, according to the treatments: no added antioxidant, 100 ppm butylated hydroxytoluene and 50, 100, 150 and 200 ppm anacardic acid. The mortadellas were stored for 90 days at 4 °C, and the analysis of lipid oxidation and color were performed. For TBARS, there was linear reduction with increased anacardic acid. According to the means test, 200 ppm anacardic acid provided the lower TBARS values. The redness decreased during storage, and, as reported by the means test, mortadella containing 200 ppm anacardic acid had lower values. The lightness of mortadellas decreased during storage. Also in accordance with the means test, mortadellas containing antioxidants had same lightness than control. The yellowness of mortadellas increased during storage. Thus, the anacardic acid is a potential natural antioxidant that could be included in chicken mortadella formulations before cooking.

Extruded snacks with the addition of different fish meals

Abstract Tilapia, salmon, tuna and sardine meals were prepared to develop and analyze extruded snacks with residue meal from fish processing. Residue meals were included in five types of corn snacks: control (0% fish meal) and four with 9% tilapia, salmon, tuna and sardine meals. Although moisture, lipids and carbohydrates rates did not differ among the snacks, protein rates increased with the increment of fish meal, reaching 11.85% in the tuna snack. Tuna and sardine snacks had the highest iron levels. The most abundant fatty acids were linoleic, oleic, palmitic, linolenic and stearic acids, with sardine, salmon and tuna snacks presenting the highest values of n-3 series fatty acids. Greater luminosity rate was reported for salmon snack, followed by tilapia, tuna and sardine snacks. The highest sensory acceptance index was verified in tilapia (78.07%) and salmon (72.40%). A 9% addition of residue meals of tilapia, salmon and tuna improved the nutritional value of the snacks.

Addition of exogenous polypeptides on the mammalian reovirus outer capsid using reverse genetics

Addition of exogenous peptide sequences on viral capsids is a powerful approach to study the process of viral infection or to retarget viruses toward defined cell types. Until recently, it was not possible to manipulate the genome of mammalian reovirus and this was an obstacle to the addition of exogenous sequence tags onto the capsid of a replicating virus. This obstacle has now been overcome by the advent of the plasmid-based reverse genetics system. In the present study, reverse genetics was used to introduce different exogenous peptides, up to 40 amino acids long, at the carboxyl-terminal end of the σ1 outer capsid protein. The tagged viruses obtained were infectious, produce plaques of similar size, and could be easily propagated at hight titers. However, attempts to introduce a 750 nucleotides-long sequence failed, even when it was added after the stop codon, suggesting a possible size limitation at the nucleic acid level.

Quick Addition of Decimals Using Reversible Conservative Logic

In recent years, reversible logic has emerged as one of the most important approaches for power optimization with its application in low power CMOS, nanotechnology and quantum computing. This research proposes quick addition of decimals (QAD) suitable for multi-digit BCD addition, using reversible conservative logic. The design makes use of reversible fault tolerant Fredkin gates only. The implementation strategy is to reduce the number of levels of delay there by increasing the speed, which is the most important factor for high speed circuits.

Ab initio benchmark study for the oxidative addition of CH4 to Pd: importance of basis-set flexibility and polarization

To obtain a state-of-the-art benchmark potential energy surface (PES) for the archetypal oxidative addition of the methane C-H bond to the palladium atom, we have explored this PES using a hierarchical series of ab initio methods (Hartree-Fock, second-order Møller-Plesset perturbation theory, fourth-order Møller-Plesset perturbation theory with single, double and quadruple excitations, coupled cluster theory with single and double excitations (CCSD), and with triple excitations treated perturbatively [CCSD(T)]) and hybrid density functional theory using the B3LYP functional, in combination with a hierarchical series of ten Gaussian-type basis sets, up to g polarization. Relativistic effects are taken into account either through a relativistic effective core potential for palladium or through a full four-component all-electron approach. Counterpoise corrected relative energies of stationary points are converged to within 0.1-0.2 kcal/mol as a function of the basis-set size. Our best estimate of kinetic and thermodynamic parameters is -8.1 (-8.3) kcal/mol for the formation of the reactant complex, 5.8 (3.1) kcal/mol for the activation energy relative to the separate reactants, and 0.8 (-1.2) kcal/mol for the reaction energy (zero-point vibrational energy-corrected values in parentheses). This agrees well with available experimental data. Our work highlights the importance of sufficient higher angular momentum polarization functions, f and g, for correctly describing metal-d-electron correlation and, thus, for obtaining reliable relative energies. We show that standard basis sets, such as LANL2DZ+ 1f for palladium, are not sufficiently polarized for this purpose and lead to erroneous CCSD(T) results. B3LYP is associated with smaller basis set superposition errors and shows faster convergence with basis-set size but yields relative energies (in particular, a reaction barrier) that are ca. 3.5 kcal/mol higher than the corresponding CCSD(T) values

Reduction of arsenic uptake by lettuce with ferrous sulfate applied to contaminated soil

Soil contamination by arsenic (As) presents a hazard in many countries and there is a need for techniques to minimize As uptake by plants. A proposed in situ remediation method was tested by growing lettuce (Lactuca sativa L. cv. Kermit) in a greenhouse pot experiment on soil that contained 577 mg As kg(-1), taken from a former As smelter site. All combinations of iron (Fe) oxides, at concentrations of 0.00, 0.22, 0.54, and 1.09% (w/w), and lime, at concentrations of 0.00, 0.27, 0.68, and 1.36% (w/w), were tested in a factorial design. To create the treatments, field-moist soil, commercial-grade FeSO4, and ground agricultural lime were mixed and stored for one week, allowing Fe oxides to precipitate. Iron oxides gave highly significant (P < 0.001) reductions in lettuce As concentrations, down to 11% of the lettuce As concentration for untreated soil. For the Fe oxides and lime treatment combinations where soil pH was maintained nearly constant, the lettuce As concentration declined in an exponential relationship with increasing FeSO4 application rate and lettuce yield was almost unchanged. Iron oxides applied at a concentration of 1.09% did not give significantly lower lettuce As concentrations than the 0.54% treatment. Simultaneous addition of lime with FeSO4 was essential. Ferrous sulfate with insufficient lime lowered soil pH and caused mobilization of Al, Ba, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sr, and Zn. At the highest Fe oxide to lime ratios, Mn toxicity caused severe yield loss.

Reduction of arsenic uptake by lettuce with ferrous sulfate applied to contaminated soil

Soil contamination by arsenic (As) presents a hazard in many countries and there is a need for techniques to minimize As uptake by plants. A proposed in situ remediation method was tested by growing lettuce (Lactuca sativa L. cv. Kermit) in a greenhouse pot experiment on soil that contained 577 mg As kg(-1), taken from a former As smelter site. All combinations of iron (Fe) oxides, at concentrations of 0.00, 0.22, 0.54, and 1.09% (w/w), and lime, at concentrations of 0.00, 0.27, 0.68, and 1.36% (w/w), were tested in a factorial design. To create the treatments, field-moist soil, commercial-grade FeSO4, and ground agricultural lime were mixed and stored for one week, allowing Fe oxides to precipitate. Iron oxides gave highly significant (P < 0.001) reductions in lettuce As concentrations, down to 11% of the lettuce As concentration for untreated soil. For the Fe oxides and lime treatment combinations where soil pH was maintained nearly constant, the lettuce As concentration declined in an exponential relationship with increasing FeSO4 application rate and lettuce yield was almost unchanged. Iron oxides applied at a concentration of 1.09% did not give significantly lower lettuce As concentrations than the 0.54% treatment. Simultaneous addition of lime with FeSO4 was essential. Ferrous sulfate with insufficient lime lowered soil pH and caused mobilization of Al, Ba, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sr, and Zn. At the highest Fe oxide to lime ratios, Mn toxicity caused severe yield loss.

Enantioselective Intramolecular Michael Addition of Nitronates onto Conjugated Esters: Access to Cyclic γ-Amino Acids with up to Three Stereocenters

A highly stereoselective synthesis of conformationally constrained cyclic γ-amino acids has been devised. The key step involves an intramolecular cyclization of a nitronate onto a conjugated ester, promoted by a bifunctional thiourea catalyst. This methodology has been successfully applied to generate a variety of γ-amino acids, including some containing three contiguous stereocenters, with very high diastereoselectivity and excellent enantioselectivity. It is postulated that an interaction that is key to the success of the process is the simultaneous coordination of the thiourea functionality to both the conjugated ester and the nitronate. Finally, the synthetic utility of these compounds is demonstrated in the synthesis of two dipeptides derived from the C- and N-termini.

Effect of addition of protein fractions extracted from flours of different baking quality on gluten rheology

The effect of change of the rheological properties of gluten with the addition of fractions with specific molecular weight was investigated. Fractions extracted from Hereward, Riband and Soissons flours were added to the dough prior to gluten extraction. Once extracted, the glutens were subjected to temperature sweeps and creep recovery rheological tests. In the temperature sweeps, Hereward fractions containing the larger polypeptides had a strengthening effect on the gluten, indicated by a decrease in tan delta and an increase in elastic creep recovery, while those fractions that comprised monomeric gliadins had a weakening effect. Adding total gluten also had a strengthening effect. For the biscuit-making flour Riband, the results were quite the reverse: all fractions appeared to strengthen the gluten network, while the addition of total gluten did not have a strengthening effect. For Soissons gluten, the addition of total gluten had a strengthening effect while adding any individual fraction weakened the gluten. The results were confirmed with creep-recovery tests.

Enhancing the oxidative stability of rice crackers by addition of the ethanolic extract of phytochemicals from Cratoxylum formosum Dyer

Craloxylum formosum Dyer is consumed throughout the year as food and medicine in Thailand. It contains large amounts of chlorogenic acid and quinic acid derivatives. The antioxidative activity of the extract was studied in refined soybean oil coating on rice crackers without any seasoning. They were stored in accelerated oxidation conditions at 40 degrees C, 80% relative humidity (RH) in the dark for 18 days. The oxidative state of each sample was monitored by analyzing of the peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) as well as by odor analysis by quantitative descriptive analysis (QDA). The C formosum extract was more effective than alpha-tocopherol due to metal ions present in the crackers, which resulted in alpha-tocopherol being less effective as an antioxidant. Sensory odor attributes of rice crackers were related more closely to TBARS than to PV values by linear regression analysis. The present study indicated that C. formosum extract was a promising source of a natural food antioxidant and was effective in inhibiting lipid oxidation in rice crackers.

A homo-proline tetrazole as an improved organocatalyst for the asymmetric Michael addition of carbonyl compounds to nitro-olefins

A new homo-proline tetrazole derivative 7 has been prepared and shown to have improved properties for achieving asymmetric Michael addition of carbonyl compounds to nitro-olefins.