Dietary N‐Glycans from Bovine Lactoferrin and TLR Modulation

1 Scope

Bovine lactoferrin (bLF) is an ingredient of food supplements and infant formulas given its antimicrobial and antiviral properties. We modified bLF enzymatically to alter its N‐glycosylation and to isolate the glycan chains. The aims of this study include (1) to evaluate whether such derivates induce responses via pattern recognition receptors namely Toll‐like receptors (TLRs) and (2) to relate those responses to their different glycosylation profiles.

2 Methods and results

The unmodified and modified bLF fractions are incubated with reporter cell lines expressing pattern recognition receptors. Afterwards, we screen for TLRs and analyze for nuclear factor kappa—light‐chain enhancer of activated B cells (NF‐κB) activation. Activation of reporter cell lines show that signaling is highly dependent on TLRs. The activation pattern of bLF is reduced with the desialylated form and increased with the demannosylated form. In reporter cells for TLR, bLF activate TLR‐4 and inhibit TLR‐3. The isolated glycans from bLF inhibit TLR‐8. TLR‐2, TLR‐5, TLR‐7, and TLR‐9 are not significantly altered.

3 Conclusion

The profile of glycosylation is key for the biological activity of bLF. By understanding how this affects the human defense responses, the bLF glycan profile can be modified to enhance its immunomodulatory effects when used as a dietary ingredient.     

The effect of olive leaves supplementation on the feed digestibility, growth performances of pigs and quality of pork meat

The influence of olive leaves supplementation on feed digestibility, growth performance of pigs and pork meat quality was investigated. Pigs fed diets with olive leaves at 5% (OL5) and 10% (OL10) levels had lower daily weight gain (DG) and daily feed intake (DFI) than pigs fed a conventional diet (OL0) but differences were not observed between groups fed with the different quantities of leaves. Additionally, pigs fed diets with leaves had the worst feed:gain ratio and showed a decrease in overall backfat. Chops from pigs fed the leaf diets had lower peroxide (PV) and conjugated diene (CD) contents than chops from pigs fed conventional diets. Moreover, chops from pigs fed with the higher quantity of leaves also showed a lower drip loss. After a storage period of 8 days at 4 °C, meat obtained from both OL5 and OL10 animals also differed (P < 0.05) in PV and %CD values from those fed a conventional diet. Since the fatty acid composition of the longissimus muscles was not different, differences in oxidative stability could only be explained by the significantly higher α-tocopherol concentration in intramuscular fat and backfat in pigs fed with olive leaf diets.     

Antioxidant and cardioprotective effects of Ilex brasiliensis: A comparative study with Ilex paraguariensis (yerba mate)

Our objective was to compare the antioxidant properties and cardiovascular effects in ischemia–reperfusion of leaves aqueous extracts of Ilex brasiliensis (B) and Ilex paraguariensis (P). In vitro systems were used to assess the antioxidant properties of the extracts. Isolated rat hearts were treated with both extracts before ischemia and myocardial function was assessed. Thiobarbituric acid reactive substances (TBARS) concentration and reduced glutathione (GSH) were also measured. B extract showed higher total phenols and ascorbic acid contents and a higher scavenging activity of peroxynitrite and ferric reducing antioxidant power (FRAP) than P extract. Postischemic systolic and diastolic functions were improved after B and P treatment. Both extracts decreased TBARS and preserved GSH content.The present study demonstrates that an aqueous extract of I. brasiliensis, similar to I. paraguariensis, protects the myocardium against ischemia–reperfusion injury and attenuates oxidative damage. These effects may be attributed to the potent antioxidant properties of the extract.     

Tocopherols in espresso coffee: Analytical method development and validation

The present paper reports the development and validation of an analytical micro-method for tocopherols quantification in espresso coffee by normal-phase HPLC with fluorescence detection. The proposed method consists in a liquid–liquid extraction with n-hexane:ethyl acetate, followed by a clean-up with dimethylformamide to eliminate co-eluting interferences. The method showed good intra- and inter-day precisions (coefficient of variation < 6.5%), good accuracies (98 ± 6%), and high correlation coefficients (r > 0.999) for standards subjected to the entire procedure. Only α- and β-tocopherols were identified in the brews. The detection and quantification limits were 0.5 and 1.4 ng/ml, for α-tocopherol, and 0.4 and 1.1 ng/ml, for β-tocopherol, respectively. A mean total tocopherol content (α + β) of 3.5 ± 0.9 μg in commercial espresso coffee blends (30 ml) was detected. The proposed method requires low solvent consumption and proved to be sensitive, precise and accurate.     

Different commercial yeast strains affecting the volatile and sensory profile of cava base wine

36 semi-industrial fermentations were carried out with 6 different yeast strains in order to assess differences in the wines' chemical and volatile profile. Two of the tested strains (Y3 and Y6) showed the fastest fermentation rates throughout 3 harvests and on 2 grape varieties. The wines fermented by three of the tested strains (Y5, Y3 and Y4) stand out for their high amounts of esters and possessed the highest fruity character. Wines from strains producing low amounts of esters and high concentrations of medium chain fatty acids, higher alcohols and six-carbon alcohols were the least appreciated at the sensory analysis. The data obtained in the present study show how the yeast strain quantitatively affects the final chemical and volatile composition of cava base wines and have repercussions on their sensory profile, independently of must variety and harvest year.     

Seasonal changes of CLA isomers and other fatty acids of milk fat from grazing dairy herds in the Azores

BACKGROUND: Season of the year associated with dietary changes has been recognized as a factor implicated in milk fat fatty acid (FA) profile in dairy cows. However, a lack of information exists concerning cows grazing all year round as is practiced in the Azores, where cows are supplemented in winter with maize silage plus concentrates, while in spring the higher grass allowance only requires supplementation with concentrate. The main objective of this study was to detect any seasonal variation of FA profile of milk fat from milk sampled in bulk tanks of 12 Azorean dairy herds. RESULTS Compared to winter milk, milk fat from spring presented a higher proportion of CLA cis‐9,trans‐11 (14.3 versus 9.6 g kg^?1 FA), C18:1 trans‐11 (32 versus 22 g kg^?1 FA), C18:2 trans‐11,cis‐15 (3.7 versus 2.2 g kg^?1 FA), CLA trans‐11,cis‐13 (0.34 versus 0.23 g kg^?1 FA) and C18:3 n‐3 (5.7 versus 5.4 g kg^?1 FA). The C18:2 n‐6/C18:3 n‐3 ratio was lower (P < 0.05) in spring. Branched‐chain FA, except the anteiso‐C15:0, were higher in spring, while odd‐chain FA (C15:0) were higher in winter. CONCLUSION: Dairy herd management in the Azores presents a seasonal variation of milk fat FA composition, where the spring milk may present increased potential benefits for human consumers. Copyright © 2008 Society of Chemical Industry     

Oil Phytosterol Concentration in Sunflower Presents a Dilution Response with Oil Weight per Grain

Phytosterols are plant sterols that present several benefits for human health. In crop species, such as sunflower, oil phytosterol concentration shows genetic and environmental variations. The reasons that cause such varied concentration of phytosterols in the oil are unknown. The aim of this work was to investigate the relationships between phytosterol concentration and composition and grain oil content in sunflower. Two sets of samples, with lines and hybrids grown in different environments in Argentina and Spain, were used to establish and validate the relationships between phytosterols and grain oil content. Oil phytosterol concentration decreased in both types of genotypes, lines, and hybrids, when oil content per grain increased. A dilution-like relationship accounted for 82% of the variability in phytosterol concentration among genotypes and environments. Phytosterol concentration rapidly increased with oil contents lower than 11.4 mg per grain. This relationship was observed for total phytosterols and each type of the phytosterols analyzed. With low oil per grain, phytosterol composition varied, with higher proportions of β-sitosterol and Δ⁷-stigmastenol. The relationships established in this work could serve to design breeding and crop management strategies.     

Development of polystyrene composites based on blue agave bagasse by in situ RAFT polymerization

A new approach for the production of polystyrene-blue agave bagasse (BAB) composite materials is presented. In this approach, dried powdered raw BAB is press molded in the presence of a coupling agent based on glycidyl methacrylate (GMA), producing a hybrid material of poly(GMA) grafted onto BAB. The in situ reversible addition-fragmentation chain transfer (RAFT) polymerization of styrene in presence of this poly(GMA)-graft-BAB hybrid material results in a reinforced composite material. These composites are characterized by Fourier-transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, gel permeation chromatography, scanning electron microscopy, impact test analyses, and dynamic mechanical analysis. The characterization results show that the amount of GMA coupling agent plays a key role in the efficiency of the process, manifested as improvement of the mechanical properties of polystyrene. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47089.