Special Issue: Infant and Child Nutrition and Foods

Milk is a natural fluid and as such contains small amounts of naturally occurring steroids. Human milk is recommended as the optimal source of nutrients for infants and young children, and it has been associated to several short- and long-term benefits. For this reason, its composition is used as a reference for designing infant formulas. However, the available information on the hormonal levels of these dairy products is scarce, and it is usually limited to estradiol and estrone. In the present study, six natural sex hormones (pregnenolone, progesterone, estrone, dehydroepiandrosterone, testosterone and androstenedione) have been extracted from sixteen milk-based infant formulas and analyzed with liquid chromatography tandem mass spectrometry (HPLC-MS/MS). The purpose of this research was to quantify natural steroid hormones in various infant formulas, to provide food and nutrition practitioners with information to estimate intakes in children. In addition, data found in the literature was used for comparison. The findings suggest that there are certain similarities between bovine milk and dairy products for infants. Furthermore, the detected levels were in general lower than those observed in human milk and/or colostrum. The reported results represent a valuable addition to the current knowledge on natural hormone content of infant foods

Food and omics: unraveling the role of food in breast cancer development

Breast cancer is the second most common cancer worldwide and the most common cause of cancer death for women. Its plasticity and variability suggest a multifactorial origin, with powerful influence of environmental factors. Current scientific evidence pinpoints food and specific nutrients as crucial factors in breast tumor development. More precisely, dietary components can actively participate in the suppression and/or progression of cancer by introducing modifications into the epigenetic landscapes of cancer. Food not only can target oncogenes and tumor-suppressor genes and modify their methylation levels, but they also can influence histone chemical modifications, non-coding RNA pathways and microbiota metabolism. Breast cancer is currently treated with surgery, radiotherapy, chemotherapy and/or therapies targeting estrogen receptor (ER) and human epidermal growth factor receptor 2 (HER2). However, the holistic omics study of the association between diet and breast health opens an interesting alternative for future breast cancer prevention and therapyS

Bacterial Diversity of Breast Milk in Healthy Spanish Women: Evolution from Birth to Five Years Postpartum

The objective of this work was to characterize the microbiota of breast milk in healthy Spanish mothers and to investigate the effects of lactation time on its diversity. A total of ninety-nine human milk samples were collected from healthy Spanish women and were assessed by means of next-generation sequencing of 16S rRNA amplicons and by qPCR. Firmicutes was the most abundant phylum, followed by Bacteroidetes, Actinobacteria, and Proteobacteria. Accordingly, Streptococcus was the most abundant genus. Lactation time showed a strong influence in milk microbiota, positively correlating with Actinobacteria and Bacteroidetes, while Firmicutes was relatively constant over lactation. 16S rRNA amplicon sequencing showed that the highest alpha-diversity was found in samples of prolonged lactation, along with wider differences between individuals. As for milk nutrients, calcium, magnesium, and selenium levels were potentially associated with Streptococcus and Staphylococcus abundance. Additionally, Proteobacteria was positively correlated with docosahexaenoic acid (DHA) levels in breast milk, and Staphylococcus with conjugated linoleic acid. Conversely, Streptococcus and trans-palmitoleic acid showed a negative association. Other factors such as maternal body mass index or diet also showed an influence on the structure of these microbial communities. Overall, human milk in Spanish mothers appeared to be a complex niche shaped by host factors and by its own nutrients, increasing in diversity over timeThe authors would like to thank the European Regional Development Funds (FEDER), grant ED431C 2018/05, for covering the costs of publicationS

High-Throughput Platforms in Real-Time PCR and Applications

The miniaturization of reactions by designing nanoliter-scale PCR platforms, as Taqman® OpenArray®, Dynamic Array™, or SmartChip, has been a big step forward in real-time PCR. Each platform has some particular characteristics that differentiate them. These nanoliter-scale PCR platforms enable substantial savings in the amount of reagents and sample because the reaction volumes are at nanoliter levels. In addition, it is possible to perform thousands of reactions in a few hours. Therefore, high-throughput real-time PCR platforms result in promising systems that are capable of processing a large number of samples simultaneously and also to perform a large number of assays per sample. All of this can be translated in the amazing applicability of this technology in all kinds of analytical fields, such as medical research, animal science, and food safety, among others

Human Milk Oligosaccharides (HMOs) and Infant Microbiota: A Scoping Review

Human milk oligosaccharides (HMOs) are the third most abundant solid component of breast milk. However, the newborn cannot assimilate them as nutrients. They are recognized prebiotic agents (the first in the newborn diet) that stimulate the growth of beneficial microorganisms, mainly the genus Bifidobacterium, dominant in the gut of breastfed infants. The structures of the oligosaccharides vary mainly according to maternal genetics, but also other maternal factors such as parity and mode of delivery, age, diet, and nutritional status or even geographic location and seasonality cause different breast milk oligosaccharides profiles. Differences in the profiles of HMO have been linked to breast milk microbiota and gut microbial colonization of babies. Here, we provide a review of the scope of reports on associations between HMOs and the infant gut microbiota to assess the impact of HMO compositionS

Magnetic molecularly imprinted stirring bar for isolation of patulin using grafting technique

The 19th International Electronic Conference on Synthetic Organic Chemistry session Polymer and Supramolecular ChemistryMycotoxins are low-molecular-weight natural products with great structural diversity produced as secondary metabolites by fungi. One of the principal toxic fungal metabolites is patulin (PAT), produced by over 30 genera of mold including species as Penicillium expansum or Penicillium griseofulvum, and normally related to vegetable-based products and fruit, mainly apple. These mold grow easily in damaged fruit or in derived-product as juices if storage conditions are deficient. Some of the most serious effects of PAT ingestion are agitation, convulsions, edema, ulceration intestinal, inflammation and vomiting. Thus, European Regulation 1881/2006 established a maximum content of 10 ppb in infant fruit juices, 50 ppb for fruit juices in adults and 25 ppb in fruit-derived products. Nowadays, the official analytical method for food adopted by AOAC International is HPLC with UV detection, using clean-up with ethyl acetate and sodium carbonate. However, the diverse drawbacks of this method (poor stability of PAT under alkaline extraction, poor resolution between PAT and co-extracted hydroxymethylfurfural) have originated interest in alternative options, such as LC methods coupled to mass spectrometry. In the last years, purification with molecularly imprinted polymers (MIP) started to be used, and are becoming promising materials for extracting different analytes present in food. Mycotoxins are too toxic or too expensive to be used as template molecules in MIP preparation. Template “bleeding” may be an additional problem, especially when dealing with very low detection levels. In the present work, a rapid and selective method based on magnetic molecularly imprinted stir-bar (MMIB) extraction has been developed for the isolation of PAT. A structural analogue, 2-oxindole, was used as dummy template. The polymer was grafted to the silanized glass surface of the stir ba

Design of a molecularly imprinted stir-bar for isolation of patulin in apple and LC-MS/MS detection

Mycotoxins are a very diverse group of natural products produced as secondary metabolites by fungi. Patulin is produced by mold species normally related to vegetable-based products and fruit, mainly apple. Its ingestion may result in agitation, convulsions, edema, intestinal ulceration, inflammation, vomiting, and even immune, neurological or gastrointestinal disorders. For this reason, the European Commission Regulation (EC) 1881/2006 established a maximum content for patulin of 10 ppb in infant fruit juice, 50 ppb for fruit juice for adults and 25 ppb in fruit-derived products. In this work, a rapid and selective method based on magnetic molecularly imprinted stir-bar (MMISB) extraction has been developed for the isolation of patulin, using 2-oxindole as a dummy template. The final extraction protocol consisted of simply pouring in, stirring and pouring out samples and solvents from a beaker with the MMISB acting inside. The magnetic device provided satisfactory recoveries of patulin (60%–70%) in apple samples. The successful MMISB approach has been combined with high performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) to determine patulin.This research was supported by the project EM 2012/153 from Consellería de Cultura, Educación e Ordenacion Universitaria, Xunta de GaliciaS

Development of a novel molecularly imprinted stir-bar for isolation of aflatoxins

The 19th International Electronic Conference on Synthetic Organic Chemistry session Polymer and Supramolecular ChemistryMycotoxins are natural substances produced as secondary metabolites by a wide variety of different species of filamentous fungi. One of the most important groups in terms of occurrence and toxicity, is the group of aflatoxins (AFs). The major members of this group are aflatoxin B1, B2, G1, G2, M1 and M2. Exposure to AFs can cause chronic and acute toxic effects or death, as they can be carcinogenic, mutagenic, teratogenic and immunosuppressive. AFB1 is considered as the strongest carcinogen of natural origin and it is normally predominant in crops as well as in food products. Aflatoxin M1 is a major metabolite of aflatoxin B1 in humans and animals and it may be present in milk from animals fed with contaminated feed. Although the toxicity of M1 is about ten times lower than B1, it is known for its hepatotoxic and carcinogenic effects. Solid phase extraction (SPE) or the clean-up with organic solvents or immunoaffinity columns (IAC) have been frequently applied in the analysis of mycotoxins from cereals and/or milk. IAC in combination with HPLC are increasingly used as reference method due to their high selectivity and good elimination of matrix interferences. However, the cost of analysis is usually high. In recent years, molecularly imprinted polymers (MIP) have been become very popular and promising materials for extracting different analytes. AFs are too toxic to be used in MIP preparation and template bleeding may be an additional problem, especially when dealing with very low levels. For this reason, a dummy template was preferred for MIP synthesis. A rapid and selective extraction method based on magnetic MIP (MMIP) has been developed for the isolation of aflatoxins (B1, B2, G1, G2, M1) using a combination of imprinted polymer and magnetite. The successful MMIP stirring “cake” (used as a stir-bar) has been combined with HPLC-MS/MS for the determination of AFM1 in milk powder (infant formulas) to demonstrate its applicability to real sample

Milk Microbiota: A Source of Antimicrobial-Producing Bacteria with Potential Application in Food Safety

Antimicrobial and biocide resistance is a major public health problem today. Therefore, one of the main scientific challenges nowadays is the search for alternatives to these substances. One of these potential alternatives are the bacteriocins. Microbiota are a potential source of bacteriocin-producing bacteria that need to be studied. In this study, a total of 40 samples of human milk and 10 samples of cow milk were collected from healthy individuals and stored at −20 °C until use. Colonies isolated from these samples that showed antimicrobial activity against Lactobacillus delbrueckii ssp. bulgaricus in the overlaid assays were selected. Well diffusion assays were carried out with the cell-free supernatant (CFS) from these colonies neutralized to pH and inhibition zones were recorded. The activity against eight common bacterial pathogens was evaluated. A total of 32 colonies with potential antimicrobial activity were isolated. The neutralized CFS of 10 strains showed antimicrobial activity against at least one pathogen tested in the well diffusion assays. Eight of the 10 CFS inhibited the growth of Staphylococcus aureus. These CFS also showed activity against Staphylococcus epidermidis, Streptococcus agalactiae, Pseudomonas aeruginosa , L. monocytogenes, Clostridium perfringens and Clostridioides difficile. The next steps of the research will be 16s rRNA sequencing to identify the species of isolates and mass spectrometry to determine the antimicrobial product produced by isolation. Finally, this study demonstrated that milk microbiota are a potential source of new producing bacteriocin bacteria that can be used in the formulation of new food productsS