Ferritin synthesis by Caco-2 cells as an indicator of iron bioavailability: Application to milk-based infant formulas

The bioavailability of iron from milk-based infant formulas was estimated by an in vitro system including enzymatic digestion, iron uptake by Caco-2 cells and ferritin determination via an enzymoimmunoassay (ELISA). Positive correlations (p < 0.01) were found between the Fe(II) added to Caco-2 cells and ferritin synthesis and between the amount of dialyzed iron added to the cell culture and ferritin synthesis. The comparison of the bioavailability of iron from different milk-based formulas showed that adapted formulas having the same composition but differing in the iron salts added yielded similar ferritin levels. The same happened with follow-up formulas differing only in the presence or absence of bifidobacterium added. However, significant differences in the amount of ferritin synthesized were recorded between the two analyzed toddler formulas. Such differences could be attributed firstly to the ascorbic acid content and perhaps also to the manufacturing process involved, because one formula was in liquid form while the other was powdered.     

Flax fibers as a raw material: How to bleach efficiently a non-woody plant to obtain high-quality pulp

Fiber crops constitute a good alternative to wood fiber for manufacturing pulp and paper. In fact, fiber plants like flax surpass wood fiber in some technical respects and also in the environmental benignity of their processing. In this work, flax fiber was subjected to environmentally friendly bleaching sequences in order to obtain a high-quality pulp. The totally chlorine-free sequences (TCF) used for this purpose (LE and LRE) included an enzyme treatment with laccase in the presence of HBT as mediator (L stage), an alkaline extraction (E stage) and a reductive treatment with NaBH₄ (R stage). The operating conditions for the L stage (laccase and HBT doses, reaction time and oxygen pressure) were optimised by using a sequential statistical plan to assess their influence on pulp properties after the E stage.Mathematical models accurately predicting brightness and kappa number in terms of the previous four variables were developed based on which the most influential factors were the laccase and HBT rates, and treatment time. By contrast, oxygen pressures of 0.2–0.6 MPa in the reactor had no effect on brightness or kappa number. The flax pulp obtained contained some oxidized cellulose that was partially degraded in the alkaline extraction step and reduced viscosity as a result. The viscosity loss associated with the presence of oxidized cellulose in the control and enzyme-treated pulp samples was efficiently recovered by using a reductive stage with sodium borohydride. Effluent was also analysed in order to assess the environmental impact of the process.     

Alternative Index for Interpretation of RTD Curves

An alternative approach for the interpretation of the residence time distribution (RTD) curves is proposed. The method has semiempirical basis, supported upon a gross fit of the tracer curve area by two triangles in order to obtain a single parameter (φ index) that indicates whether the system tends to a completely mixed or to a plug flow hydraulic behavior. In order to verify its applicability, 28 experiments were carried out in a laboratory tank (138 L). In these experiments, the influence of aeration, packing, and number of baffles on the tank hydraulic behavior was assessed using the index as well as conventional models. The general results obtained in the laboratory tank experiments showed that mixed tanks tend to have a larger dead volume fraction (DVF) than plug-flow tanks and that packed tanks tend to have a smaller DVF than nonpacked tanks. This index provides a reliable, quick, and simple method for the interpretation of the RTD curves when hydraulic behavior trends or tank modifications for hydraulic improvements are evaluated.     

Removal of aqueous phenolic compounds from a model system by oxidative polymerization with turnip (Brassica napus L var purple top white globe) peroxidase

Turnip roots, which are readily available in Mexico, are a good source of peroxidase, and because of their kinetic and biochemical properties have a high potential as an economic alternative to horseradish peroxidase (HRP). The efficiency of using turnip peroxidase (TP) to remove several different phenolic compounds as water‐insoluble polymers from synthetic wastewater was investigated. The phenol derivatives studied included phenol, 2‐chlorophenol, 3‐chlorophenol, o‐cresol, m‐cresol, 2,4‐dichlorophenol and bisphenol‐A. The effect of pH, substrate concentration, amount of enzyme activity, reaction time and added polyethylene glycol (PEG) was investigated in order to optimize reaction conditions. A removal efficiency ≥85% was achieved for 0.5 mmol dm^?3 phenol derivatives at pH values between 4 and 8, after a contact time of 3 h at 25 °C with 1.28 U dm^?3 of TP and 0.8 mmol dm^?3 H₂O₂. Addition of PEG (100–200 mg dm^?3) significantly reduced the reaction time required (to 10 min) to obtain >95% removal efficiency and up to 230% increase in remaining TP activity. A relatively low enzyme activity (0.228 U dm^?3) was required to remove >95% of three phenolic solutions in the presence of 100–200 mg dm^?3 PEG. TP showed efficient and fast removal of aromatic compounds from synthetic wastewaters in the presence of hydrogen peroxide and PEG. These results demonstrate that TP has good potential for the treatment of phenolic‐contaminated solutions. © 2002 Society of Chemical Industry     

Plant food supplement (PFS) market structure in EC Member States, methods and techniques for the assessment of individual PFS intake

The popularity of herbal products, especially plant food supplements (PFS) and herbal medicine is on the rise in Europe and other parts of the world, with increased use in the general population as well as among specific subgroups encompassing children, women or those suffering from diseases such as cancer. The aim of this paper is to examine the PFS market structures in European Community (EC) Member States as well as to examine issues addressing methodologies and consumption data relating to PFS use in Europe. A revision of recent reports on market data, trends and main distribution channels, in addition an example of the consumption of PFS in Spain, is presented. An overview of the methods and administration techniques used to assess individual food consumption as a starting point, including their uses and limitations, as well as some examples of studies that collect Food Supplement (FS) information, including herbal/botanical/plant-derived products are also discussed. Additionally, the intake estimation process of food nutrients is described and used to propose the PFS ingredients intake estimation process. Nationally representative PFS consumption data is scarce in Europe. The majority of studies have been conducted in Scandinavia and the UK. However the heterogeneity of definitions, study design and objectives make it difficult to compare results and extrapolate conclusions.     

Synthesis and Organo-Catalyzed Ring-Opening of a Six-Membered Heterocycle Combining Phosphonate and Ester Functions

The synthesis of a difunctional P-heterocycle combining phosphonate and ester moieties in a six-membered ring is described. Using trifluoromethane sulfonic acid HOTf as organocatalyst, ring-opening with neopentyl alcohol readily occurs with complete selectivity for O-acyl bond cleavage. In turn, ring-opening polymerization proceeds in a controlled manner when an excess of P-heterocycle is used. Copolymerization with ϵ-caprolactone is also reported and semi-batch conditions are shown to enable regular incorporation of the phosphonate moieties along the polymer chains.     

Interaction between the peptide glutathione and linoleic acid hydroperoxide

Incubation experiments in order to study the influence of some parameters in the fluorescence products formation have been carried out. It has been observed a greater efficiency with the relation linoleic acid hydroperoxide:glutathione, 2:1, and a temperature of 37 °C. The complex formed working with labelled linoleic acid has been separated in two main fractions. The first one (without radioactivity) is fluorescent with excitation and emission maxima at 350 nm and 440 nm, respectively. It has been confirmed that this fraction consists of a complex of glutathione and short chain aldehydes. The fluorescence of the complex did not decrease by treatment with NaBH₄ or with pH. The NH₂ and SH groups take part in the lipid-peptide complex formation. The second, highly radioactive fraction includes free hydroperoxides and short chain hydroxy fatty acids.     

Trace elements in edible fats. VIII. Soybean oil “demetalization” with cation exchange resins

The effects of different solvents, degree of dilution, type of resin, and temperature were studied to determine the optimum conditions for “demetalization” of soybean oils with cation exchange resins. Prooxidant metals in crude soybean oils in acetone orn-hexane solutions can be effectively removed when passed through columns of a strong cation exchange resin. Supported by Grant No. FG-Sp-103-60 under Public Law 480. Agricultural Util. Res. Program. USDA.     

Trace elements in edible fats. IX. Influence of demetalization on the oxidative and flavor stabilities of soybean oil

Crude and degummed soybean oils were demetalized by passing through columns packed with cation exchange resins. These oils were refined, bleached, deodorized and compared with untreated oils for oxidative and flavor stabilities. Treatment of oils with resin lowered metal content and increased stability as measured by oxidative and sensory tests. Supported by Grant No. FG-Sp-103-60 under Public Law 480, Agricultural Utilization Program, USDA.     

Protein isolates from two Mediterranean legumes: Lathyrus clymenum and Lathyrus annuus. Chemical composition,functional properties and protein characterisation

Protein isolates were analysed from two Mediterranean legumes, Lathyrus clymenum and L. annuus. Protein isolates were prepared by alkaline extraction, including sodium sulphite and acid precipitation of Lathyrus proteins at their isoelectric point (pH 4.5). The percentage of proteins recovered from L. annuus and L. clymenum flours during the preparation of the protein isolates was around 60%. Chemical composition, nutritional parameters, main functional properties and protein composition of Lathyrus protein isolates were studied. L. annuus and L. clymenum protein isolates contained 81.07% and 82.4% of proteins, respectively, and they have a balanced content of essential amino acids, except for sulphur amino acids, with respect to the FAO pattern. The in vitro protein digestibility increased in the protein isolates to 93% and 95% in L. annuus and L. clymenum, respectively. Functional properties were similar to those observed in other legumes protein isolates. These results confirm the interest of local crops as sources of high value protein products obtained after convenient protein extraction procedures and the removal of antinutritional components. These high added value protein isolates are of interest for the food industry and for the revalorisation of L. annuus and L. clymenum favouring the bioconservation of Lathyrus.