Iron nanoparticles as food additives and food supplements, regulatory and legislative perspectives

Recently, the use of nanotechnology in food has gained great interest. Iron nanoparticles with unique chemical, physical and structural properties allow their potential use mainly as iron fortifiers, colorants and antimicrobial agents. However, in the market we can find only supplements and food colorants based on iron nanoparticles. Their use in food fortification has so far been focused only on in vitro and in vivo experimental studies, since the toxicological evaluation of these studies has so far been the basis for the proposals of laws and regulations, which are still in an early stage of development. Therefore, the aim of this work was to summarize the use of the different forms of iron nanoparticles (oxides, oxyhydroxides, phosphates, pyrophosphates and sulfates) as food additives and supplements and to resume the perspectives of legislation regarding the use of these types of nanoparticles in the food industry.

Characterization of total phenol and flavonoid contents, colour, functional properties from honey samples with different floral origins

Honey has long been used as a food and has been reported to have potential health benefits. In this work, total phenol content, colour and antioxidant and hepatoprotective activities of honey samples of different floral origins from the State of Hidalgo, Mexico were explored using in vitro assays. Hepatoprotective activity was measured by inhibitition of β-glucuronidase; gastroprotective activity was determined by inhibition of urease; antioxidant activity was evaluated by 2,2'-Azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) methods. All the parameters showed significant differences (p<0.05) among honey samples. The total phenolic content ranged from 18.02 to 102.77 mg GAE 100 g-1. The colour ranged from extra light amber to dark amber. Inhibition of β-glucuronidase ranged from 23.70% to 36.00%, while urease inhibition ranged between 7.64% and 63.80%. The antioxidant activity by ABTS was between 44.68 and 441.56 mg AAE 100 g-1, and DPPH showed activities ranging from 35.64 to 573.06 mg AAE 100 g-1. All honey samples contained bioactive compounds and displayed functional properties; therefore, the honeys from this region of Mexico offer attractive characteristics for their potential use in the food industry.

Modification of Oxalis tuberosa starch with OSA, characterization and application in food-grade Pickering emulsions

The emulsifying properties of Oxalis tuberosa starch (native and chemically modified) were evaluated in Pickering emulsions based on the emulsification index, emulsion stability over time and emulsion morphology. The best conditions of chemical modification were found by esterification of starch with octenyl succinic anhydride (OSA) at a concentration of 3% and a reaction time of 2 h, achieving a degree of substitution of 0.033 ± 0.001. The results obtained using Fourier-transform infrared spectroscopy, a Rapid Visco Analyzer, and differential scanning calorimetry, indicated that the starch underwent a change in its structure and that the insertion of the OSA groups was achieved. The amphipathic characteristics of OSA starch were evaluated by forming oil-in-water emulsions. Various concentrations of OSA-starch granules (1, 2.5 and 5 wt%) were used. A higher concentration of particles produced a smaller droplet size of emulsions (76.5 ± 0.9 μm) compared to those formed at a lower concentration of 1% (92.5 ± 1.0 μm). Therefore, the starch modified with OSA displayed the necessary characteristics to be adsorbed at the oil-water interface, achieving Pickering emulsion stabilization.

The Addition of Microencapsulated or Nanoemulsified Bioactive Compounds Influences the Antioxidant and Antimicrobial Activities of a Fresh Cheese

The objective of this study was to compare the effects of the incorporation of microcapsules or nanoemulsions with Opuntiaoligacantha on the quality of fresh cheese. Three treatments were established: Control, cheese with microcapsules (Micro), and cheese with nanoemulsion (Nano). The parameters evaluated were physicochemical (moisture, ash, fat, proteins, and pH), microbiological (mesophilic aerobic bacteria, mold-yeast, and total coliforms), functional (total phenols, flavonoids, and antioxidant capacity), and texture (hardness, elasticity, cohesion, and chewiness) during storage for 45 days at 4 °C. The results showed that adding microcapsules and nanoemulsion did not affect the physicochemical parameters of the cheese. Total coliforms decreased in all samples from the first days of storage (Control: 4.23 ± 0.12, Micro: 3.27 ± 0.02, and Nano: 2.68 ± 0.08 Log10 CFU), as well as aerobic mesophiles and mold-yeast counts. Regarding the functional properties, an increase in total phenols was observed in all treatments. The texture profile analysis showed that the addition of microcapsules and nanoemulsion influenced hardness (Control: 8.60 ± 1.12, Micro: 1.61 ± 0.31, and Nano: 3.27 ± 0.37 N). The antimicrobial effect was greater when nanoemulsions were added, while adding microcapsules influenced the antioxidant activity more positively.

Collagen Hydrolysates for Skin Protection: Oral Administration and Topical Formulation

Antioxidants are molecules that delay or inhibit the oxidation of other molecules. Its use significantly increased in recent years in the diet of people. Natural antioxidants are replacing the use of synthetic antioxidant ingredients due to their safety, nutritional, and therapeutic values. Hydrolyzed collagen (HC) is a popular ingredient considered to be an antioxidant. This low molecular weight protein has been widely utilized due to its excellent biocompatibility, easy biodegradability, and weak antigenicity. It is a safe cosmetic biomaterial with good moisturizing properties on the skin. The antioxidant properties of HC are conditioned to the size of the molecule: the lower the molecular weight of peptides, the greater the ability to donate an electron or hydrogen to stabilize radicals. The antioxidant capacity of HC is mostly due to the presence of hydrophobic amino acids in the peptide. The exact mechanism of peptides acting as antioxidants is not clearly known but some aromatic amino acids and histidine are reported to play an important role in the antioxidant activity. Oral ingestion of HC increases the levels of collagen-derived peptides in the blood torrent and improves the skin properties such as elasticity, skin moisture, and transepidermal water loss. Additionally, daily intakes of HC protect the skin against UV melasma, enhances the fibroblast production and extracellular matrix of the skin. HC has been identified as a safe cosmetic ingredient for topical formulations with good moisturizing properties at the stratum corneum layer of the skin. It reduces the effects of skin aging (dryness, laxity, and wrinkles). The use of HC as a principal ingredient in safe formulations for skin protection was reviewed and compared when it is used by topical and/or oral administration.

Study of the antioxidant properties of extracts obtained from nopal cactus (Opuntia ficus-indica) cladodes after convective drying

BACKGROUND

The process of convective drying was evaluated in terms of the bioactive compounds contained in nopal samples before and after dehydration. Total polyphenol, flavonoid, flavonol, carotene and ascorbic acid contents were determined in undehydrated and dehydrated samples. Two drying temperatures (45 and 65 °C) and two air flow rates (3 and 5 m s(-1) ) were evaluated. The rheology of samples under the best drying conditions was also studied, since it provides important information regarding processing (mixing, flow processing) as well as the sensory attributes (texture) of rehydrated samples.

RESULTS

Non-Newtonian shear-thinning behaviour was observed for samples dried at 45 °C, while samples dried at 65 °C showed shear-thickening behaviour, possibly caused by thermal chain scission of high-molecular-weight components.

CONCLUSION

The best conditions for bioactive compound preservation were a drying temperature of 45 °C and an air flow rate of 3 m s(-1) , resulting in 40.97 g phenols, 23.41 g flavonoids, 0.543 g β-carotene and 0.2815 g ascorbic acid kg(-1) sample as shown in table 3.

[Granulocyte colony-stimulating factor in the treatment of febrile neutropenia]

PURPOSE

To determine whether granulocyte colony-stimulating factor (G-CSF) used in addition to antibiotic therapy, in patients with chemotherapy-induced febrile neutropenia shortens the period of fever, neutropenia and hospitalization.

PATIENTS AND METHODS

The study was prospective. Patients with lymphoblastic acute leukemia (LAL) were included. They received intensive chemotherapy of induction, intensification, or consolidation. At random, a group received amikacin-ceftriaxone; if no had response after 3 days, we added vancomicin and, after 7 days, amphotericin. The other group received in addition these antibiotics, granulocyte colony-stimulating factor.

RESULTS

The groups were comparable in the magnitude of the initial neutropenia (< 0.5 x 10(9)/L), site of the infection, chemotherapy received germs isolated, age, and sex. The patients of the group that received FEC-G were cured in the course of 3.1 days; in the group without FEC-G, this occurred in 7.2 days (p = 0.0001). At the end of the infectious episode, the number of neutrophils, in the group with FEC-G, was of 1.9 x 10(9)/L versus 0.7 x 10(9)/L (p = 0.0009). The mortality was of one and two cases (p = 0.46). The global mortality was 7.5%.

CONCLUSIONS

The addition of FEC-G to the treatment with antibiotics, in febrile neutropenia, decreases duration of days with fever, hospitalization and neutropenia. However, the frequency of cure is not augmented.