Identification of allergen encoding sequences in a novel food ingredient from Moringa oleifera leaves.

Alternative sources of edible proteins are required to feed the world's growing population, such as Moringa oleifera leaves, a protein source with a balanced amino acid composition. Since Moringa leaf proteins is a novel food in the EU and UK, an assessment of their potential allergenicity of is required. Proteins from Moringa leaf powder were characterised using traditional proteomic approaches.

Effect of sprouting on the proteome of chickpea flour and on its digestibility by ex vivo gastro-duodenal digestion complemented with jejunal brush border membrane enzymes.

The demand for sustainably produced proteins is increasing with the world population and is prompting a dietary shift toward plant sourced proteins. Vegetable proteins have lower digestibility and biological value compared to animal derived counterparts. We explored sprouting of chickpea seeds as a strategy for improving digestibility.

The effect of nitrogen fertilization on the expression of protein in wheat and tritordeum varieties using a proteomic approach.

Wheat, an essential ingredient for several bakery preparations, is also responsible for gluten-related diseases in sensitive subjects. The effect of the N fertilization rate (80 vs 160 kg N ha) on gluten protein expression profile has been evaluated considering two soft wheats (landrace and modern) and one tritordeum cultivar (cv), grown in the same experimental field in North Italy. The proteins of refined flour were characterized through advanced proteomic approaches, including chromatography (RP-HPLC) and electrophoresis.

Comprehensive analysis of the peanut allergome combining 2-DE gel-based and gel-free proteomics.

In this work, we explored the "deep" seed peanut proteome by using both two dimensional electrophoresis (2-DE)-based analysis run under reducing and non-reducing condition (protein-centric) and LC-MS/MS gel-free proteomic (peptide-centric). The former approach allowed to identify high molecular weight disulfide-linked Ara h 1 and Ara h 3 heteroligomers and Ara h 1 homoligomers linked through covalent bonds other than disulfides. The occurrence of these protein complexes revealed natural interactions between Ara(s) subunits with a possible involvement in the allergenic potential of peanut.

Production, digestibility and allergenicity of hemp (Cannabis sativa L.) protein isolates.

Hemp (Cannabis sativa L.), traditionally cultivated for industrial use and harvested for fibers and seeds, has raised much interest as a sustainable crop in the last years. Recently, hemp seeds and derived oil have started to be used in a variety of food products.

Monitoring molecular composition and digestibility of ripened bresaola through a combined foodomics approach.

In this work, the effects of maturation time and simulated gastrointestinal digestion on the molecular and peptide profiles of "Bresaola Valtellina" were assessed through the foodomics approach, in this case food proteomics and peptidomics combined to other analytical and biological assays, aiming at depicting a holistic food quality. Human digestion of this Italian cured meat product was simulated using an in vitro static protocol and the degree of proteolysis and the in vitro bioactivity of the soluble free compounds in the digestates were evaluated by biochemical assays, e.g.

A non-canonical phosphorylation site in β-casein A from non-Mediterranean water buffalo makes quantifiable the adulteration of Italian milk with foreign material by combined isoelectrofocusing-immunoblotting procedures.

The need of controlling illegal addition of water buffalo (WB) milk from foreign countries to the Italian counterpart devoted to the production of Protected Denomination of Origin (PDO) Mozzarella di Bufala Campana (MBC) cheese has promoted the development of simple, fast and cheap isoelectrofocusing (IEF) methods for evaluating the nature of the raw material to be used according to a high-throughput sample multiplexing format, avoiding the use of dedicated mass spectrometry-based procedures. Thus, combined proteomic methods were here integrated with optimized western blotting protocols in solving the complex IEF pattern of casein (CN) mixtures observed when Italian and foreign WB milk are mixed together. Identification of internally deleted α-CN hepta-phosphorylated species as well as of still unknown β-CN A hexa-phosphorylated and N-terminally-nicked β-CN A phosphorylated forms present uniquely in foreign WB milk samples, allowed recognizing these molecules as adulteration markers to be assayed in combined IEF-immunoblotting procedures; the latter ones showing optimal migration characteristics to be used in routine assays.

Eventual limits of the current EU official method for evaluating milk adulteration of water buffalo dairy products and potential proteomic solutions.

The European reference method (ERM) recognises the fraudulent addition of bovine (B) milk in water buffalo (WB) milk/dairy products based on concomitant isoelectric focusing (IEF) detection of B γ- and γ-CN fragments after corresponding plasminolysis. We here used proteomics to characterise false positive results occurring in the ERM as being due to WB β-CN(f100-209), which is also formed after plasminolysis of genuine WB milk/dairy products and comigrates in IEF with B γ-CN. These ERM limitations were overcome by a dedicated proteomic procedure based on loading of B/WB milk/cheese CN extracts on a hydroxyapatite column, in situ trypsinolysis and elution of B β-CN(f1-25)4P and WB β-CN(f1-28)4P proteotypic peptides.

Simultaneously tracing the geographical origin and presence of bovine milk in Italian water buffalo Mozzarella cheese using MALDI-TOF data of casein signature peptides.

Water buffalo (WB) casein (CN) and curd samples from indigenous Italian and international breeds were examined with the objective of identifying signature peptides that could function as an indicator to determine the origin of their milk products. CN in complex mixtures were digested with trypsin, and peptide fragments were subsequently identified by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS). The unique presence of a β-CN A variant and an internally deleted αs1-CN (f35-42) variant in international WB milk samples was ascertained by identifying signature tryptic peptides from either dephosphorylated or native CN.

Microalgae as human food: chemical and nutritional characteristics of the thermo-acidophilic microalga Galdieria sulphuraria.

The use of microalgae as a food source is still poorly developed because of the technical difficulties related to their cultivation and the limited knowledge about their chemical composition and nutritional value. The unicellular red microalga Galdieria sulphuraria has a very high daily productivity and its cultivation under acidic conditions avoided any bacterial contamination. G.

The occurrence of genetic polymorphism and related non-allelic proteins increases the compositional complexity of goat α((s1)) -CN.

A genetic survey on three autochthonous goat breeds reared in Italy was carried out by a proteomic approach. This methodology, further to providing the phenotypic frequency of identified α(s1) genetic variants, allowed to determine (i) the additional constitutive presence of a non-allelic 'α(s1) -casein (CN) F like' protein in goat 'strong' α(s1) variants; (ii) an α(s1) -CN B(2) like protein, expressed at very low quantitative level, in goat 'weak' α(s1) -CN variants, and, as main focus; (iii) the occurrence of a new α(s1) -CN D(1) variant characterised by the lack of α(s1) (f59-69) sequence otherwise encoded by exon 9 in goat α(s1) B(2) reference. The same exon skipping event had been identified since 1990, as responsible of the 'weak quantitative class' of α(s1) -CN D variant (0.

Occurrence of major whey proteins in the pH 4.6 insoluble protein fraction from UHT-treated milk.

A clear picture of the protein rearrangement in milk following UHT-treatment was drawn by a comparative analysis of the pH 4.6 soluble protein fraction (SPF) and the pH 4.6 insoluble protein fraction (IPF) recovered from raw and UHT-treated milk samples.

Lactosylated casein phosphopeptides as specific indicators of heated milks.

Casein phosphopeptides (CPP) were identified in small amounts in milks heated at various intensities by using matrix-assisted laser desorption/ionization (MALDI) time-of-flight mass spectrometry. CPP selectively concentrated on hydroxyapatite (HA) were regenerated using phosphoric acid mixed in the matrix. Unphosphorylated peptides not retained by HA were removed by buffer washing.

Fast isoelectric focusing and antipeptide antibodies for detecting bovine casein in adulterated water buffalo milk and derived mozzarella cheese.

Plasmin hydrolysis of water buffalo casein (CN) can liberate a peptide comigrating with bovine gamma(2)-CN. Occurrence of this peptide may lead to false-positive detection of cow's milk for a genuine water buffalo cheese when it is analyzed by applying a fast version of the European official method for detecting bovine casein in water buffalo cheese. After isoelectric focusing of CN plasminolysates, performed according to the official method, immunoblot analysis with antipeptide antibodies was assayed to distinguish between gamma(2)-CN and the interfering bovine gamma(2)-CN-like peptide.

Immunochemical detection of formylated gamma(2)-casein in cheese.

An immunochemical approach has been developed to detect the use of formaldehyde as a bacteriostatic agent in dairy products. A synthetic peptide, reproducing the first five amino acid residues of the gamma(2)-casein sequence, was formylated to generate the novel haptenic structure, already well-recognized in formaldehyde-treated milk and arising out of molecular rearrangement after the addition of formaldehyde to the alpha-amino group of the histidine residue at the N terminus of gamma(2)-casein. A polyclonal antibodies preparation produced against the formylated peptide adduct proved to be a highly specific analytical tool for detecting the formylated adduct of gamma(2)-casein in formaldehyde-treated milk.