Sonochemical Syntheses of a One-Dimensional Mg(II) Metal-Organic Framework: A New Precursor for Preparation of MgO One-Dimensional Nanostructure

Nanostructure of a MgII metal-organic framework (MOF), {[Mg(HIDC)(H2O)2]·1.5H2O}n (1) (H3IDC = 4,5-imidazoledicarboxylic acid), was synthesized by a sonochemical method and characterized by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy, and elemental analyses. The effect of concentration of starting reagents on size and morphology of nanostructured compound 1 has been studied. Calcination of the bulk powder and nanosized compound 1 at 650°C under air atmosphere yields MgO nanostructures. Results show that the size and morphology of the MgO nanoparticles are dependent upon the particles size of compound 1

Conventional solid-state fermentation impacts the white lupin proteome reducing the abundance of allergenic peptides

The demand for high-quality and sustainable protein sources is on the rise. Lupin is an emerging plant-based source of protein with health-enhancing properties; however, the allergenic potential of lupins limits their widespread adoption in food products. A combination of discovery and targeted quantitative proteome measurements was used to investigate the impact of solid-state fermentation induced by Rhizopus oligosporus on the proteome composition and allergenic protein abundances of white lupin seed. In total, 1,241 proteins were uniquely identified in the fermented sample. Moreover, the effectiveness of the solid-state fermentation in reducing the abundance of the tryptic peptides derived from white lupin allergens was demonstrated. Comparably, a greater decrease was noted for the major white lupin allergen based on -conglutin peptide abundances. Hence, conventional solid-state fermentation processing can be beneficial for reducing the potential allergenicity of lupin-based foods. This finding will open new avenues for unlocking the potential of this under-utilised legume

Evaluation of the major seed storage proteins, the conglutins, across genetically diverse narrow-leafed lupin varieties

Lupin seeds have an excellent nutritional profile, including a high proportion of protein and dietary fiber. These qualities make lupin seeds an ideal candidate to help meet the growing global demand for complementary sources of protein. Of consequence to this application, there are nutritional and antinutritional properties assigned to the major lupin seed storage proteins—referred to as α-, β-, δ- and γ-conglutins The variation in the abundance of these protein families can impact the nutritional and bioactive properties of different lupin varieties. Hence, exploring the conglutin protein profiles across a diverse range of lupin varieties will yield knowledge that can facilitate the selection of superior genotypes for food applications or lupin crop improvement. To support this knowledge generation, discovery proteomics was applied for the identification of the 16 known conglutin subfamilies from 46 domestic and wild narrow-leafed lupin (NLL) genotypes. Consequently, the diversity of abundance of these proteins was evaluated using liquid chromatography–multiple reaction monitoring-mass spectrometry (LC–MRM-MS). This comparative study revealed a larger variability for the β- and δ-conglutin content across the lines under study. The absence/lower abundance of the β2- to β6-conglutin subfamilies in a subset of the domesticated cultivars led to substantially lower overall levels of the allergenic β-conglutin content in these NLLs, for which the elevation of the other conglutin families were observed. The diversity of the conglutin profiles revealed through this study—and the identification of potential hypoallergenic genotypes—will have great significance for lupin allergic consumers, food manufactures as well as grain breeders through the future development of lupin varieties with higher levels of desirable bioactive proteins and lower allergen content

Lupin: Prospective superfood or potential allergen?

The demand for plant-based protein sources is on the rise. Lupins, important members of the legume family, are one of the richest natural sources of protein and fibre and can positively contribute to global food and nutritional security. Despite their strong potential, lupins remain under-utilised as a human food and are predominantly grown as green manure and livestock feed. One constraint to the widespread adoption of lupins in the food industry is allergenicity, which has led to its inclusion in the list of food allergens subjected to mandatory labelling in many countries. The research presented herein focused on the study of proteins in lupin seeds, aiming to incentivise exploitation of this under-utilised legume by enhancing the available proteome-level knowledge and addressing the allergenicity challenges attributed to this legume. Firstly, the efficiency of four solvents (IPA-DTT, Tris-HCl, Urea and IPA→Urea) in extracting proteins from three narrow-leafed lupin genotypes (Tanjil, Unicrop and P27255) were evaluated through global discovery and quantitative proteomic approaches. The integration of complementary solvent systems enabled identification of 2,760 proteins from these genotypes. In addition, the proteome-wide relative quantitative analysis highlighted differences in the protein profiles of the wild and domesticated lupin genotypes and demonstrated the substantial influence of the protein extraction method on the proteome coverage and downstream biological interpretation of the data. The diversity of the major lupin seed storage proteins, known as conglutins, were assessed across a panel of 46 genetically diverse narrow-leafed lupin genotypes. The differentiation and relative quantitation of the 16 conglutin sub-families, belonging to the four major α-, β-, γ-, and δ- families, was achieved by monitoring a set of maker peptides specific to each protein sub-family. Whilst this comparative evaluation determined distinct differences in the conglutin profiles of the lines under investigation, the major variability was observed for the β-, and δ-conglutin sub-families, wherein, the allergenic β-conglutin proteins were found at considerably lower levels in a subset of Australian and Polish domesticated varieties. These narrow-leafed lupin cultivars can serve as potential hypoallergenic varieties and be implemented in breeding programs for further enhancing the lupin grain as a human food ingredient. Finally, a combination of discovery and targeted quantitative proteomic approaches were applied to examine the changes driven by solid-state fermentation (induced by the starter culture Rhizopus oligosporus) in the white lupin allergenic protein profiles. The comparative proteomics study of the allergen derived peptides across the pre-fermented and fermented samples revealed a significant decrease in the levels of ~94% of the monitored peptides as result of fermentation. This effect was more prominent across the β-conglutin peptides, for which a decrease \u3e 50% was observed for ~70% of the monitored peptides. These observations suggest good efficiency of solid-state fermentation for the degradation of the allergenic proteins and development of innovative lupin-based food products with reduced allergenicity. The findings of these proteomic studies contribute to advancing the proteome-level knowledge available for lupin seeds, thereby providing opportunities to now enhance lupin seed protein composition and stimulate the broader application of this grain legume as a food ingredient