Functional Genomics for Plant Breeding 3.0

Functional genomics, as a scientific discipline, has significantly transformed the landscape of plant breeding in recent years [...].

Determination of Molecular Dimensions of Carbohydrate Polymers (Polysaccharides) by Size Exclusion Chromatography (SEC)

Calibrated size exclusion chromatography (SEC) is a useful tool for the analysis of molecular dimensions of polysaccharides. The calibration takes place with a set of narrow distributed dextran standards and peak position technique. Adapted columns systems and dissolving processes enable for the adequate separation of carbohydrate polymers. Plant-extracted fructan (a homopolymer with low molar mass and excellent water solubility) and mucilage (differently structured, high molar mass heteropolysaccarides that include existing supramolecular structures, and require a long dissolving time) are presented as examples of the versatility of this technique. Since narrow standards similar to the samples (chemically and structurally) are often unavailable, it must be noted that the obtained molar mass values and distributions by this method are only apparent (relative) values, expressed as dextran equivalents.

Monosaccharide Analysis After One-Pot Derivatization Followed by Reverse-Phase Liquid Chromatography Separation and UV/Vis Detection

Derivatization of monosaccharides with 1-phenyl-3-methyl-5-pyrazolone (PMP) introduces two chromophores per sugar molecule. Their separation on a superficially porous C18 reverse-phase column, using common liquid chromatography equipment, results in short analysis times (under 20 min) and high sensitivity (limit of quantitation 1 nmol). This method allows for complex monosaccharide mixtures to be separated and quantified using a reasonably simple and safe derivatization procedure.

Identification of inulin-responsive bacteria in the gut microbiota via multi-modal activity-based sorting

Prebiotics are defined as non-digestible dietary components that promote the growth of beneficial gut microorganisms. In many cases, however, this capability is not systematically evaluated. Here, we develop a methodology for determining prebiotic-responsive bacteria using the popular dietary supplement inulin. We first identify microbes with a capacity to bind inulin using mesoporous silica nanoparticles functionalized with inulin. 16S rRNA gene amplicon sequencing of sorted cells revealed that the ability to bind inulin was widespread in the microbiota. We further evaluate which taxa are metabolically stimulated by inulin and find that diverse taxa from the phyla Firmicutes and Actinobacteria respond to inulin, and several isolates of these taxa can degrade inulin. Incubation with another prebiotic, xylooligosaccharides (XOS), in contrast, shows a more robust bifidogenic effect. Interestingly, the Coriobacteriia Eggerthella lenta and Gordonibacter urolithinfaciens are indirectly stimulated by the inulin degradation process, expanding our knowledge of inulin-responsive bacteria.

Safety of a dual potential prebiotic system from Mexican agave "Metlin® and Metlos®", incorporated to an infant formula for term newborn babies: a randomized controlled trial

RATIONALE

Infant formulae are being supplemented with probiotics, prebiotics, or symbiotic despite uncertainties regarding their efficacy. Mexican agave is an interesting source of fructans with particular features and with potential prebiotic effects.

MATERIAL AND METHODS

RCT in 600 healthy term babies (20 ± 7 days), allocated to receive standard infant formula (control) or infant formula added with a dual prebiotic system "Metlin® and Metlos®", from Mexican agave. Primary outcomes include stools frequency, stools consistency, gastrointestinal intolerance (frequency of abdominal distension, flatulency, regurgitations, vomiting). Secondary outcomes include changes on weight and height along the study and frequency of dermatologic problems (eczema).

RESULTS

In 66,120 days of total follow-up, there were no differences on the frequency of stools passage (Human Milk: 3.8 ± 2.4 evacuations per day; Pro + Metlin + Metlos 3.6 ± 2.0; Pro + Metlin 3.6 ± 2; only Pro 3.4 ± 2.3¸ only formula 3.4 ± 2.0; p NS). Consistency of stools was similar between human milk and prebiotics supplemented groups. Also the frequency of gastrointestinal symptoms was significantly low between these groups.

CONCLUSIONS

Fructans derivate from agave and added to infant formula are safe and well tolerated by Mexican healthy term babies.