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Olive (Olea europaea L.) is one of the most important fruit species in the Mediterranean basin, where 95% of the world's olive orchards are planted, and has become an economically valuable crop worldwide due to an increasing demand in olive oil for human consumption. The aim of the present research was to classify Tunisian olive cultivars based on their phenolic profile and to test the potentiality of chemometrics as a tool for cultivars discrimination. The phenolic compounds present in 21 samples of olive leaves, collected during the normal picking period for olive oil production in South Tunisia, were analysed by liquid chromatography mass spectrometry. Models based on principal component analysis (PCA) and hierarchical cluster analysis (HCA) was used for discrimination purposes as a function of the tree varieties and cultivation zone. Qualitative and quantitative compositional analysis revealed 12 major phenolic compounds among which oleuropein (110.38–4741.62 mg/kg), hydroxytyrosol (5.40–290.19 mg/kg), apigenin 7-O-glucoside (9.44–2475.53 mg/kg), tyrosol (2.10–174.62 mg/kg), catechin (0–37.60 mg/kg) and vanillic acid (3.23–256.57 mg/kg) were identified. Oleuropein showed the highest amount in Fougi cultivar (4741.62 mg/kg), whereas the lowest level was registered in Zarrazi injassi cultivar (110.38 mg/kg). However, Zalmati Zarzis exhibited high concentrations of tyrosol, vanillic and caffeic acid, and vanillin. In general, rutin and luteolin 7-Oglucoside were the two main flavonoids detected. Dendrogram analysis revealed three main clusters, further confirmed through PCA.

Pectin is the methylated ester of polygalacturonic acid and has a wide range of applications. It can be used in food and animal feed as well as in pharmaceutical and cosmetic products. Pectin is traditionally used as a gelling agent in fruit-based products, as a stabilizer in some fruit juices and milk drinks and fruit filling for bakery and confectionary products, but their potential applications differ according to their chemical composition. Therefore, at this stage of development, it is of a great importance to find fast, reliable methods to not only identify and quantify pectin, but also to determine its chemical structure and composition when it is extracted from plant matrices, wastes and by-products. The present review will focus on the analytical tools used to identify and quantify the amount of pectin obtained from plant matrices, wastes and by-products as well as determining its chemical and structural composition.

Plant biostimulants are receiving great interest for boosting root growth during the first phenological stages of vegetable crops. The present study aimed at elucidating the morphological, physiological, and metabolomic changes occurring in greenhouse melon treated with the biopolymer-based biostimulant Quik-link, containing lateral root promoting peptides, and lignosulphonates. The vegetal-based biopolymer was applied at five rates (0, 0.06, 0.12, 0.24, or 0.48 mL plant–1) as substrate drench. The application of biopolymer-based biostimulant at 0.12 and 0.24 mL plant–1enhanced dry weight of melon leaves and total biomass by 30.5 and 27.7%, respectively, compared to biopolymer applications at 0.06 mL plant–1and untreated plants. The root dry biomass, total root length, and surface in biostimulant-treated plants were significantly higher at 0.24 mL plant–1and to a lesser extent at 0.12 and 0.48 mL plant–1, in comparison to 0.06 mL plant–1and untreated melon plants. A convoluted biochemical response to the biostimulant treatment was highlighted through UHPLC/QTOF-MS metabolomics, in which brassinosteroids and their interaction with other hormones appeared to play a pivotal role. Root metabolic profile was more markedly altered than leaves, following application of the biopolymer-based biostimulant. Brassinosteroids triggered in roots could have been involved in changes of root development observed after biostimulant application. These hormones, once transported to shoots, could have caused an hormonal imbalance. Indeed, the involvement of abscisic acid, cytokinins, and gibberellin related compounds was observed in leaves following root application of the biopolymer-based biostimulant. Nonetheless, the treatment triggered an accumulation of several metabolites involved in defense mechanisms against biotic and abiotic stresses, such as flavonoids, carotenoids, and glucosinolates, thus potentially improving resistance toward plant stresses.

Interest in using polyphenols as modulators of the activity of starch digestive enzymes is increasing. The main purpose of this study was to investigate the role of phenolic compounds characterising pigmented maize flours in the modulation of in vitro starch digestibility. Flours from three different pigmented maize varieties were evaluated under cooking conditions and compared to common yellow maize (YM). The untargeted metabolomics-based approach comprehensively annotated around 300 phenolic compounds, with a high distribution of anthocyanins and phenolic acids (in free and bound fractions of maize samples) and significant differences across genotypes. Following in vitro starch digestion, the cooked pigmented maize flours showed higher resistant starch content (from 5.1 to 6.9 g /100 g dry matter), as well as lower starch hydrolysis index (HI) when compared to YM flour, with the “Rostrato Rosso” maize having the lowest HI (i.e., 61). Coherently, multivariate statistics following metabolomics showed the discrimination potential of anthocyanins' profile after cooking, characterising the “Rostrato Rosso” during in vitro digestion. These findings might be related to the modulation of enzyme activity by phenolic compounds during in vitro digestion. Therefore, the use of pigmented maize flours might help in the formulation of gluten-free foods with slowly digestible starches by exploiting the wide phenolic composition of these matrices.

In an effort to increase the nutritional value of common gluten-free (GF) cereal-based foods, GF cookies using alfalfa seed flour (ASF), at different substitution levels to common rice flour (0% as control, 15%, 30% and 45% w/w), were produced. Crude protein, total dietary fibre, total polyunsaturated, total n-3 and n-6 fatty acid contents increased linearly (pÂ&nbsp

In recent years, the enhancement of common gluten-free (GF) cereal-based foods with ingredients rich in phytochemicals such as polyphenols (PP) is gaining interest. However, the comprehensive screening of PP is complex due to their chemical diversity, as well as because many of them are found at low concentration levels, as conjugated forms, and because they do undergo transformation by the colonic microflora. With this aim, the high-resolution mass spectrometry based metabolomics profiling may provide more inclusive information concerning the identification, quantification and dynamics of PP in complex matrices. This mini-review is focused on the potential of metabolomics in the untargeted evaluation of phenolic profile and bioaccessibility in GF cereal-based food products.

BACKGROUND Pest control in post-harvest food storage represents a great challenge in the sustainable prevention of food losses, and insecticide-treated netting may represent a valid alternative to traditional practices such as the direct application of insecticides. In our work, the efficacy of a permethrin-incorporated net, in combination with polypropylene or jute sacking, was tested for the control of Sitophilus oryzae. Contamination of maize grain by permethrin from the treated netting was also evaluated. RESULTS A 98% control of S. oryzae was achieved using permethrin-treated netting. Both jute and polypropylene acted as additional barriers, increasing efficacy to 100%. The results also showed the contamination of maize kernel by permethrin released from the treated netting. The concentration of residues in maize kernels increased with increasing temperature; however, use of jute or polypropylene significantly reduced (by 87% to 97%) the concentration of residues transferred to maize kernels. CONCLUSIONS Permethrin-treated netting provided a high level of efficacy in the post-harvest protection of maize. Several factors influenced permethrin residue concentrations in grains when treated nets are used. Therefore, solutions should be found to prevent contamination of food stored in the bags that are treated with insecticides. © 2017 Society of Chemical Industry

Arbuscular mycorrhizal fungi (AMF) are plant growth promoters that ameliorate plant-water relations and the nutrient uptake of wheat. In this work, two cultivars of Triticum spp., a bread and a durum wheat, grown under drought stress and inoculated or not by AMF, are evaluated through a shotgun proteomic approach. The AMF association had beneficial effects as compared to non-mycorrhizal roots, in both bread and durum wheat. The beneficial symbiosis was confirmed by measuring morphological and physiological traits. In our work, we identified 50 statistically differential proteins in the bread wheat cultivar and 66 differential proteins in the durum wheat cultivar. The findings highlighted a modulation of proteins related to sugar metabolism, cell wall rearrangement, cytoskeletal organization and sulphur-containing proteins, as well as proteins related to plant stress responses. Among differentially expressed proteins both cultivars evidenced a decrease in sucrose:fructan 6-fructosyltransferas. In durum wheat oxylipin signalling pathway was involved with two proteins: increased 12-oxo-phytodienoic acid reductase and decreased jasmonate-induced protein, both related to the biosynthesis of jasmonic acid. Interactome analysis highlighted the possible involvement of ubiquitin although not evidenced among differentially expressed proteins. The AMF association helps wheat roots reducing the osmotic stress and maintaining cellular integrity. Biological significance Drought is one of the major constraints that plants must face in some areas of the world, associated to climate change, negatively affecting the worldwide plant productivity. The adoption of innovative agronomic protocols may represent a winning strategy in facing this challenge. The arbuscular mycorrhizal fungi (AMF) inoculation may represent a natural and sustainable way to mitigate the negative effects due to drought in several crop, ameliorating plant growth and development. Studies on the proteomic responses

The comprehensive phenolic fingerprint of Calligonum azel Maire plant fractions, collected from the Tunisian Desert, have been assessed for the first time as a source of natural antioxidants. Total phenolic content (TPC), Trolox Equivalent Antioxidant Capacity (TEAC) in scavenging DPPH[rad], ABTS[rad]+and Ferric Reducing Antioxidant Power (FRAP) were determined. C. azel Maire showed a relevant content in phenolic compounds, which are related to the antioxidant activity. The flowers presented the highest antioxidant capacity against DPPH free radicals, while the leaves showed the highest scavenging capacity against ABTS. As for the FRAP assay, results showed that the roots had the highest ferric reducing antioxidant power. Methanol extracts of the four organs were screened by ultra high performance liquid chromatography coupled to quadruple time of flight mass spectrometry and the identified phenolics were further quantified. Flavones and flavanols were the most abundant phenolic compounds identified, and were quantitatively measured as luteolin and catechin equivalents. Although the phenolic profile was diverse between the four organs, the obtained results showed that Calligonum azel Maire is an excellent source of various natural antioxidants with high radical scavenging capacities, which could be used in food preservation. Further studies on the isolation of such compounds appear to be of high interest.

Vanilla is a flavoring recovered from the cured beans of the orchid genus Vanilla. Vanilla ×tahitensis is traditionally cultivated on the islands of French Polynesia, where vanilla vines were first introduced during the nineteenth century and, since the 1960s, have been introduced to other Pacific countries such as Papua New Guinea (PNG), cultivated and sold as “Tahitian vanilla,” although both sensory properties and aspect are different. From an economic point of view, it is important to ensure V. ×tahitensis traceability and to guarantee that the marketed product is part of the future protected designation of the origin “Tahitian vanilla” (PDO), currently in progress in French Polynesia. The application of metabolomics, allowing the detection and simultaneous analysis of hundreds or thousands of metabolites from different matrices, has recently gained high interest in food traceability. Here, metabolomics analysis of phenolic compounds profiles was successfully applied for the first time to V. ×tahitensis to deepen our knowledge of vanilla metabolome, focusing on phenolics compounds, for traceability purposes. Phenolics were screened through a quadrupole-time-of-flightmass spectrometer coupled to a UHPLC liquid chromatography system, and 260 different compounds were clearly evidenced and subjected to different statistical analysis in order to enable the discrimination of the samples based on their origin. Eighty-eight and twenty three compounds, with a prevalence of flavonoids, resulted to be highly discriminant through ANOVA and Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) respectively. Volcano plot analysis and pairwise comparisons were carried out to determine those compounds, mainly responsible for the differences among samples as a consequence of either origin or cultivar. The samples from PNG were clearly different from the Tahitian samples that were further divided in two different groups based on the differe

Cooking by boiling dry pasta could have varying degrees of influence on nutritional and functional components. In the present study, its effect on total phenolic content and antioxidant capacity, as well as on the comprehensive profile of free and bound phenolics, was investigated in six commercial gluten-free (GF) pasta products. Overall, the heat treatment caused a significant reduction (P < 0.01) of the total phenolic content as well as FRAP reducing power and ORAC radical scavenging, with significant differences among the pasta samples considered. The highest values were recorded in free phenolic fraction remaining in black rice (41 mg gallic acid equivalents 100 g− 1 and 25 mmol Trolox Equivalents 100 g− 1) and quinoa (24 mg gallic acid equivalents 100 g− 1 and 14 mmol Trolox Equivalents 100 g− 1) cooked GF pasta. Significant correlations (P < 0.01) could be found between total phenolics and both the antioxidant capacity assays performed. UHPLC-ESI/QTOF-MS mass profiling allowed confirming the spectrophotometric results, while identifying the amount of free and bound fractions. Among phenolic classes, lignans exhibited the highest decrease during the cooking process, followed by stilbenes and flavonoids. However, phenolic acids and other phenolics showed the highest stability. Furthermore, cooking by boiling strongly lowered the bound-to-free ratio of phenolic compounds, by an averaged factor ranging from 14-folds for flavonoids to 5-folds for other classes of phenolics.

Industrial hemp cultivation in Europe is dual-purpose, with stalks providing fibers and hurds, and seeds being used for food, feed and pharmaceutical applications. Economic sustainability of hemp cultivation should encompass the possibility of recovering non-narcotic secondary metabolites from hemp by-products (leaves, leaflets and bracts) originating from seed harvest and seed cleaning procedures. Surprisingly, no information is currently available on the contents of high added value bioactive compounds (CBD, CBG, cannflavin A, Δ9-THC) in industrial hemp inflorescence and threshing residues. This observation provided a rationale for investigating the issue on three monoecious varieties grown in Northern Italy. The concentration of target compounds was monitored from full-flowering until plant senescence by LC–MS/MS analysis of methanolic extracts of the plant biomass. The anti-inflammatory prenylated flavonoid cannflavin A was present in all varieties at levels mainly affected by genotype and air temperature. Conversely, the concentration of CBD, currently the clinically most promising non-narcotic cannabinoid, correlated to the overall extent and distribution of precipitation during growing cycle. Our findings suggest that postponing harvest after seed maturity increases the CBD contents and increase the CBD/Δ9-THC ratio in harvest threshing.

Vinegar is an inexpensive commodity, and economic considerations require that a relatively low-cost raw material be used for its production. An investigation into the use of a new, alternative substrate – pineapple waste – is described. This approach enables the utilization of the pineapple's (Ananas comosus) peels and core, which are usually discarded during the processing or consumption of the fruit. Using physical and enzymatic treatments, the waste was saccharified, and the resulting substrate was fermented with Saccharomyces cerevisiae for 7–10 days under aerobic conditions at 25 °C. This resulted in an alcohol yield of approximately 7%. The alcoholic medium was then used as a seed broth for acetic fermentation using Acetobacter aceti as the inoculum for approximately 30 days at 32 °C to obtain 5% acetic acid. Samples were analyzed at the beginning and end of the acetification cycle to assess the volatile and fixed compounds by GC–MS and UHPLC-QTOF-MS. The metabolomic analysis indicated that L-lysine, mellein, and gallic acid were significantly more concentrated in the pineapple vinegar than in the original wine. Higher alcohols, aldehydes, and ketones characterized the aroma of the final pineapple vinegar, whilst off-flavors were significantly reduced relative to the initial wine. This study is the first to highlight the metabolite profile of fruit vinegar with a slight floral aroma profile derived from pineapple waste. The potential to efficiently reduce the post-harvest losses of pineapple fruits by re-using them for products with added food values is also demonstrated.

The fate of phenolic compounds, along with short-chain fatty acids (SCFAs) production kinetics, was evaluated on six different commercial gluten-free (GF) pasta samples varying in ingredient compositions, focussing on the in vitro faecal fermentation after the gastrointestinal digestion. A general reduction of both total phenolics and reducing power was observed in all samples, together with a substantial change in phenolic profile over 24 h of faecal fermentation, with differences among GF pasta samples. Flavonoids, hydroxycinnamics and lignans degraded over time, with a concurrent increase in low-molecular-weight phenolic acids (hydroxybenzoic acids), alkylphenols, hydroxybenzoketones and tyrosols. Interestingly, discriminant analysis also identified several alkyl derivatives of resorcinol as markers of the changes in phenolic profile during in vitro fermentation. Furthermore, degradation pathways of phenolics by intestinal microbiota have been proposed. Considering the total SCFAs and butyrate production during the in vitro fermentation, different fermentation kinetics were observed among GF pasta post-hydrolysis residues.

The characterization of phenolic fingerprints in common gluten-free flours is still scarce. Total phenolic and anthocyanin contents, antioxidant capacity and the entire phenolic profile were investigated for extracts from chickpea, sorghum, quinoa, black rice, lentil, amaranth, brown rice, oat and white rice flours, using soft wheat flour as a comparison. The highest phenolic content was found in black rice, followed by quinoa extracts (147.9 and 87.2 mg gallic acid equivalents 100 g−1, respectively). Consistently, antioxidant capacity was highest in black rice and quinoa flours (34 mmol trolox equivalents 100 g−1), while anthocyanins were highest in black rice flour. Data showed a high correlation between phenolic content and both reducing and scavenging activities, with Pearson's coefficient of 0.90 and 0.91, respectively. Although the entire phenolic profile was diverse and differed among flours, these represent a valuable source of health-promoting compounds, mainly belonging to flavonoids, phenolic acids and lignans.

Tomatoes are important in human nutrition, as they are a source of carotenoids and phenolic compounds. However, transformation processes may alter the nutritional value of foods, decreasing the concentration of health-promoting compounds. This work aimed to explore the effects of industrial transformation on processed tomatoes (crushed pulp, puree and paste), as well as the effect of the different pre-processing technologies, rather than different manufacturing sites, in producing tomato paste. Results demonstrate that phenolics profiling can distinguish between different processed products as well as different paste pre-treatments (namely cold, warm and hot break), even though the latter underwent a final thermal treatment at > 100 °C. Analogously, the different processing sites could be discriminated thanks to their characteristic phenolic fingerprint. The greatest differences identified were between conjugated forms of flavonoids, phenylpropanoids and lignans. The latter were the most labile phenolics, followed by flavonoids and then phenylpropanoids. Results provide evidence for the potential of phenolic fingerprint to support traceability of transformation processes and to investigate their effect on the nutritional value of processed tomatoes.

The aim of the trial was to test the effects of cluster spray treatments by a solution (0.03%) of chitosan, on the grape secondary metabolite synthesis of V. vinifera cv. Montepulciano. A proteomic and metabolomic approach was developed in order to investigate the enzymes and the final metabolites affected by elicitation. Pathway analysis of differential proteins highlighted the involvement of pterostilbene and triterpenoid (ursolate, oleanolate, betulinate) biosynthesis, and the metabolomic analysis showed an increasing of triterpenoids and pterostilbene in treated grapes.

Pesticides generate transformation products (TPs) when they are released into the environment. These TPs may be of ecotoxicological importance. Past studies have demonstrated how difficult it is to predict the occurrence of pesticide TPs and their environmental risk. The monitoring approaches mostly used in current regulatory frameworks target only known ecotoxicologically relevant TPs. Here, we present a novel combined approach which identifies and categorizes known and unknown pesticide TPs in soil by combining suspect screening time-of-flight mass spectrometry with in silico molecular typology. We used an empirical and theoretical pesticide TP library for compound identification by both non-target and target time-of-flight (tandem) mass spectrometry, followed by structural proposition through a molecular structure correlation program. In silico molecular typology was then used to group TPs according to common molecular descriptors and to indirectly elucidate their environmental parameters by analogy to known pesticide compounds with similar molecular descriptors. This approach was evaluated via the identification of TPs of the triazole fungicide tebuconazole occurring in soil during a field dissipation study. Overall, 22 empirical and 12 yet unknown TPs were detected, and categorized into three groups with defined environmental properties. This approach combining suspect screening timeof-flight mass spectrometry with molecular typology could be extended to other organic pollutants and used to rationalize the choice of TPs to be investigated towards a more comprehensive environmental risk assessment scheme.

Several foods on the market, such as yogurt and fermented milk, include mixtures of prebiotics and probiotic microorganisms effective in promoting the proliferation and equilibrium of intestinal bacteria, thus improving gut health. Particularly, researchers and the public have shown increasing interest in the combination of probiotics with natural substances that promote health or that can act as substrates to promote bacterial growth. The aim of this study is to evaluate the effects of different extracts of Aloe barbadensis and Aloe arborescens in fermented milk, taking into account boththe prebiotic effect of aloe polysaccharides and the antimicrobial activity of several secondary metabolites. The results demonstrate a beneficial effect of 5% aloe inner gel on Lactobacillus growth and confirm the antimicrobial activity of the phenolic compounds peculiar of green rind extracts.

Leaves of globe artichoke are food industry byproducts gaining interest due to their therapeutic and nutraceutical potential. The total phenolics, flavonoids, and flavonols content as well as radical scavenging capacity and reducing antioxidant power were determined in leaves of 19 artichoke cultivars. An untargeted analysis based on high-resolution mass spectrometry was then carried out to profile phenolic compounds and sesquiterpene lactones (STLs). The phenolic profile of leaf extracts from different cultivars was widely diverse and included flavonoids, hydroxycinnamic acids, tyrosols, and lignans. Grosheimin and its derivative were the most abundant STLs in all artichoke cultivars. Among the examined cultivars, “Campagnano”, “Grato 1”, and “Violetto di Provenza” were found to be the richest in polyphenols and presented the highest antioxidant activity, whereas “Blanca de Tudela” and “Carderas” were characterized by a high STLs content. Hence, specific artichoke cultivars can be selected as the source of natural antioxidants with a desired profile of nutraceutical compounds like phenolics and STLs.

Protein hydrolysates (PHs) is an important group of plant biostimulants defined as mixtures of polypeptides, oligopeptides and amino acids which are manufactured from protein sources using partial hydrolysis. PHs are generally applied as foliar sprays or near the roots. PHs are widely used in agricultural crops largely for improving plant nutrient uptake, growth, yield and fruit quality and also for their ameliorating effect on crop tolerance to abiotic stresses. In the current paper, we give an update of the chemical characteristics, the timing and frequency of PHs application, the effects of PHs on plant metabolism and physiology, the biostimulant activities on yield and product quality. We report several experimental data on the application of a commercial plant derived-protein hydrolysate ‘Trainer’ on agricultural crops grown under different environmental conditions.

There is a growing interest among consumers and researchers in the globe artichoke [Cynara cardunculus L. subsp. scolymus (L.) Hegi] leaf extract due to its nutraceutical and therapeutic properties. The application of an abiotic stress such as salinity can activate the stress-signaling pathways, thus enhancing the content of valuable phytochemicals. The aim of this study was to assess the metabolic changes in artichokes by probing the leaf metabolome of artichoke plants grown in a floating system and exposed to a relatively mild (30 mM) potassium chloride (KCl) salt stress. Potassium chloride treatment decreased the leaf dry biomass of artichoke, macro- and microelements in leaves (e.g., Ca, Mg, Mn, Zn, and B) but increased the concentrations of K and Cl. Metabolomics highlighted that the hormonal network of artichokes was strongly imbalanced by KCl. The indole-3-acetic acid conjugates, the brassinosteroids hormone 6-deoxocastasterone, and even more the cytokinin precursor N6-(Delta- 2-isopentenyl)-adenosine-50-triphosphate, strongly increased in leaves of KCl-treated plants. Moreover, KCl saline treatment induced accumulation of GA4, a bioactive form additional to the already known GA3. Another specific response to salinity was changes in the phenolic compounds profile, with flavones and isoflavones being decreased by KCl treatment, whereas flavonoid glycosides increased. The osmotic/oxidative stress that salinity generates also induced some expected changes at the biochemical level (e.g., ascorbate degradation, membrane lipid peroxidation, and accumulation of mannitol phosphate). These latter results help explain the molecular/physiological mechanisms that the plant uses to cope with potassium chloride stress exposure.

Leaf extracts of cultivated cardoon (Cynara cardunculus L. var. altilis DC) are an important source of phenols. Soilless culture represents an important and alternative tool to traditional agriculture, since it allows a precise control of plant nutrition and the maximization of yield and quality of the product. Reducing N supply, while keeping quantity as high as possible is desirable for environmental and health-related reasons, especially that N deficiency can lead to improved concentrations of secondary plant metabolites. Two greenhouse experiments were carried out in order to determine the effect of a decreasing NO3:Cl ratio (80:20, 60:40, 40:60, or 20:80) and nitrate deprivation (0, 5, 10, or 15 days before harvest) on biomass production, leaf chlorophyll content and fluorescence, mineral composition, and phytochemicals in leaves of cardoon ‘Bianco Avorio’ grown in a floating system. Total phenols, flavonoids and antioxidant capacity increased linearly with Cl availability, especially when nitrate was replaced by 80% of chloride (20:80 NO3 :Cl ratio), without having a detrimental effect on yield. Total nitrogen and nitrate concentration in leaves decreased linearly with increasing Cl in the nutrient solution. Total phenols and antioxidant capacity recorded after 15 days of nitrate deprivation were higher by 43.1, 42.8, and 44.3% and by 70.5, 40.9, and 62.2%, at 59, 97 and 124 days after sowing, respectively compared to the control treatment. The decrease in leaf nitrate content recorded under N-deprivation occurred more rapidly than the reduction in total nitrogen. Thus, up to 15 days of nitrate withdrawal can lower nitrates without sharply reduce total nitrogen or affecting growth and biomass of cultivated cardoon. The use of N-free nutrient solution prior to harvest or the replacement of nitrates with chlorides could be adopted among growers to improve the quality of the product and enhance sustainability of crop production system.

Abiotic stresses such as salinity and metal contaminations are the major environmental stresses that adversely affect crop productivity worldwide. Crop responses and tolerance to abiotic stress are complex processes for which “-omic” approaches such as metabolomics is giving us a newest view of biological systems. The aim of the current research was to assess metabolic changes in lettuce (Lactuca sativa L.), by specifically probing the root metabolome of plants exposed to elevated isomolar concentrations of NaCl and ZnSO4. Most of the metabolites that were differentially accumulated in roots were identified for stress conditions, however the response was more intense in plants exposed to NaCl. Compounds identified in either NaCl or ZnSO4 conditions were: carbohydrates, phenolics, hormones, glucosinolates, and lipids. Our findings suggest that osmotic stress and the consequent redox imbalance play a major role in determining lettuce root metabolic response. In addition, it was identified that polyamines and polyamine conjugates were triggered as a specific response to ZnSO4. These findings help improve understanding of how plants cope with abiotic stresses. This information can be used to assist decision-making in breeding programs for improving crop tolerance to salinity and heavy metal contaminations.

Natural pesticides have attracted substantial interest due to the increase in organic agriculture and enhanced attention to environmental pollution. Plant Growth Promoting Bacteria (PGPB) are applied for both disease control and growth enhancement; PGPBs are known to elicit Induced Systemic Response (ISR) in plants. However, less is known about the effect of botanical pesticides, such as the azadirachtincontaining neem extracts, on plant metabolism. This study aimed to investigate the effects of foliar application of the above-mentioned natural pesticides on the metabolic profiling of tomato. Leaf application of Bacillus subtilis fostered Induced Systemic Resistance (ISR) in treated plants via the Jasmonic acid pathway, and enhanced production of secondary metabolites such as flavonoids, phytoalexins and auxins. Changes in sterols and terpenes, as well as an increase in glucosinolates were also observed. Interestingly, azadirachtin-treated tomatoes also showed an increase in ISR and our results revealed that most of the enriched metabolites are shared with a B. subtilis treatment, suggesting conserved biochemical responses. These (un)expected findings indicate that plants are not insensitive to application of natural pesticide and while Azadirachtin is applied as a direct pesticide, it also stimulates a defense response in tomatoes very similar to B. subtilis induced ISR.

The ability of the grapevine to activate defense mechanisms against some pathogens has been shown to be linked to the synthesis of resveratrol and other stilbenes by the plant (inducible viniferins). Metabolized viniferins may also be produced or modified by extracellular enzymes released by the pathogen in an attempt to eliminate undesirable toxic compounds. Because of the important properties of resveratrol, there is increasing interest in producing wines with higher contents of this compound and a higher nutritional value. Many biotic and abiotic elicitors can trigger the resveratrol synthesis in the berries, and some examples are reported. Under the same elicitation pressure, viticultural and enological factors can substantially affect the resveratrol concentration in the wine. The production of high resveratrol-containing grapes and wines relies on quality-oriented viticulture (suitable terroirs and sustainable cultural practices) and winemaking technologies that avoid degradation of the compound. In general, the oenological practices commonly used to stabilize wine after fermentation do not affect resveratrol concentration, which shows considerable stability. Finally the paper reports on two sirtuin genes (SIRT) expressed in grapevine leaves and berries and the role of resveratrol on the deacetylation activity of the encoded enzymes.

The phytochemical profile of Aloe barbadensis Mill. and Aloe arborescens Mill. was investigated using colorimetric assays, triple quadrupole and time-of-flight mass spectrometry, focusing on phenolic secondary metabolites in the different leaf portions. Hydroxycinnamic acids, several characteristic anthrones and chromones, the phenolic dimer feralolide and flavonoids such as flavones and isoflavones were identified. The stable radical DPPH test and the ORAC assay were then used to determine the in vitro radical scavenging. The outer green rind was the most active, while the inner parenchyma was much less effective. The 5-methylchromones aloesin, aloeresin A and aloesone were the most active among the pure secondary metabolites tested. The results suggest that several compounds are likely to contribute to the overall radical scavenging activity, and indicate that leaf portion must be taken into account when the plant is used for its antioxidant properties.

In recent years, new strategies have been proposed in order to improve the sustainability of production systems for horticultural crops. A promising tool would be the use of substances and/or microorganisms defined also as ‘biostimulants’ able to enhance crop quality parameters, nutrient efficiency and abiotic stress tolerance. Protein hydrolysates (PHs) are an important group of plant biostimulants based on a mixture of peptides and amino acids that have received increasing attention in the recent years due to their positive effects on crop performances. PHs are mainly produced by enzymatic and/or chemical hydrolysis of proteins from animal- or plant-derived raw materials. The current review gives an overview of the biostimulant properties of PHs on productivity and product quality of horticultural crops, in par- ticular fruit trees, vegetables, flower crops and ornamentals. After a brief introduction on PHs as plant biostimulants, this review focuses on the classification and chemical composition of PHs according to the source of proteins and method of protein hydrolysis. The plant uptake and transport of amino acids and peptides and the effects of PHs on primary and secondary metabolism as well as the biochemical and physiological processes conferring tolerance to abiotic stress are also covered. The review concludes by proposing several perspectives for future research aiming to understand the mode of action of PHs based on their composition and also to define the suitable time and dose of application.

Triple quadrupole mass spectrometry (QqQ) is the most popular and widely used technique used to analyze pesticide residues in food and environmental compartments. However, recent advances in quadrupole-time-of-flight mass spectrometry (Q-TOF) may lead to this approach becoming a useful tool for analysis of pesticide residues. In this work, results of QqQ and Q-TOF were compared to determine their accuracy, when determining the concentration of herbicides and their metabolites in water. Double distilled and river water were therefore spiked with 18 analytes, differing in physical–chemical properties, and then directly analyzed either by QqQ and Q-TOF mass spectrometry. Results of Q-TOF were comparable to QqQ. The latter, operating in tandem mass spectrometry, was superior in terms of compound coverage, LOQ and precision for most analytes. However, results between the two analysis methods were comparable for LOD, linearity range (4 orders of magnitude) and accuracy. Validation parameters in pure and surface water showed contrasting results. Overall, the results of this study suggest that Q-TOF may represent a valid alternative to triple quadrupole, although the specific mass spectrometer under use still plays a major role.

The phytochemical profile of Aloe barbadensis Mill. and Aloe arborescens Mill. was investigated using colorimetric assays, triple quadrupole and time-of-flight mass spectrometry, focusing on phenolic secondary metabolites in the different leaf portions. Hydroxycinnamic acids, several characteristic anthrones and chromones, the phenolic dimer feralolide and flavonoids such as flavones and isoflavones were identified. The stable radical DPPH-test and the ORAC assay were then used to determine the in vitro radical scavenging. The outer green rind was the most active, while the inner parenchyma was much less effective. The 5-methylchromones aloesin, aloeresin A and aloesone were the most active among the pure secondary metabolites tested. The results suggest that several compounds are likely to contribute to the overall radical scavenging activity, and indicate that leaf portion must be taken into account when the plant is used for its antioxidant properties.

Zinc salts occurring in soils can exert an osmotic stress toward plants. However, being zinc a heavy metal, some more specific effects on plant metabolisms can be forecast. In this work, lettuce has been used as a model to investigate salt and zinc stresses at proteome level through a shotgun tandem MS proteomic approach. The effect of zinc stress in lettuce, in comparison with NaCl stress, was evaluated to dissect between osmotic/oxidative stress related effects, from those changes specifically related to zinc. The analysis of proteins exhibiting a fold change of 3 as minimum (on log 2 normalized abundances), revealed the involvement of photosynthesis (via stimulation of chlorophyll synthesis and enhanced role of photosystem I) as well as stimulation of photophosphorylation. Increased glycolytic supply of energy substrates and ammonium assimilation [through formation of glutamine synthetase (GS)] were also induced by zinc in soil. Similarly, protein metabolism (at both transcriptional and ribosomal level), heat shock proteins, and proteolysis were affected. According to their biosynthetic enzymes, hormones appear to be altered by both the treatment and the time point considered: ethylene biosynthesis was enhanced, while production of abscisic acid was up- regulated at the earlier time point to decrease markedly and gibberellins were decreased at the later one. Besides aquaporin PIP2 synthesis, other osmotic/oxidative stress related compounds were enhanced under zinc stress, i.e., proline, hydroxycinnamic acids, ascorbate, sesquiterpene lactones, and terpenoids biosynthesis. Although the proteins involved in the response to zinc stress and to salinity were substantially the same, their abundance changed between the two treatments. Lettuce response to zinc was more prominent at the first sampling point, yet showing a faster adaptation than under NaCl stress. Indeed, lettuce plants showed an adaptation after 30 days of stress, in a more pronounced way in the case of z

The phytochemical profile of Aloe barbadensis Mill. and Aloe arborescens Mill. was investigated using colorimetric assays, triple quadrupole and time-of-flight mass spectrometry, focusing on phenolic secondary metabolites in the different leaf portions. Hydroxycinnamic acids, several characteristic anthrones and chromones, the phenolic dimer feralolide and flavonoids such as flavones and isoflavones were identified. The stable radical DPPH test and the ORAC assay were then used to determine the in vitro radical scavenging. The outer green rind was the most active, while the inner parenchyma was much less effective. The 5-methylchromones aloesin, aloeresin A and aloesone were the most active among the pure secondary metabolites tested. The results suggest that several compounds are likely to contribute to the overall radical scavenging activity, and indicate that leaf portion must be taken into account when the plant is used for its antioxidant properties.

Supplemental calcium application has been reported to alleviate the detrimental effect of NaCl-induced salinity on crop growth. Iso-molar solutions of NaCl and NaCl plus CaCl2 were used to study the osmotic and ionic effects of salinity on leaf dry biomass production and nutraceutical quality of cardoon (Cynara cardunculus L. var. altilis DC) grown in a floating system. A basic nutrient solution (control; T1) was enriched with 15mM of NaCl + 10mM of CaCl2 (T2), 30mM of NaCl (T3), 30mM of NaCl + 20mM of CaCl2 (T4), or 60 mM of NaCl (T5). NaCl at 60 mM induced a 52% reduction of total leaf dry biomass compared with the control (T1); the iso-molar solution enriched with 20 mM of CaCl2 (T4) increased the total leaf dry biomass production in comparison with treatment containing NaCl at 60mM (T5).Moreover, at moderate salinity (T2 and T3), the partial replacement of NaCl with 10 mM of CaCl2 (T2) in treatment containing 30 mM of NaCl did not help to reduce the adverse effect of NaCl on total leaf dry biomass production. Results of leaf mineral analysis demonstrated that the partial replacement of NaCl with CaCl2 reduced the accumulation of sodium and the nutrient imbalance. Nutrient solutions enriched with CaCl2 did not increase the accumulation of the osmoprotectant proline in leaves. Nutraceutical value of cardoon leaves was generally improved by saline treatments compared with the control. The regression analysis between phenolic compounds and antioxidant activity showed that total phenols and chlorogenic acid were the major determinants of antioxidant activity in cardoon leaf biomass. In conclusion, the partial replacement ofNaClwithCaCl2 improved the leaf dry biomass production of cardoon only at the highest salinity levels with a limited effect on nutraceutical quality of leaves.

Plant-derived protein hydrolysates represent new biostimulant products able to improve crop tolerance to abiotic stresses. The aim of the study was to determine growth, root morphology, SPAD index, chlorophyll fluorescence, leaf mineral composition, and metabolic profiling of greenhouse lettuce either untreated or treated (root or leaf-root application) with a plant-derived protein hydrolysate. For foliar application, plants were sprayed with a solution containing 2.5 ml L−1 of biostimulant, whereas for root application, 100 mL of solution with the same concentration was applied to the growing medium at weekly intervals. Lettuce plants were supplied with two nutrient solutions: non-salt control (1 mM NaCl) or 25 mM NaCl. Salt stress decreased shoot and root dry biomass, SPAD index, chlorophyll fluorescence, leaf mineral composition and increased foliar proline concentration. Root and leaf-root application of the biostimulant increased fresh yield, dry biomass and root dry weight of lettuce under salinity conditions. This was associated with an improvement of plant nitrogen metabolism and an increase of the Fv/Fm-ratio efficiency in biostimulant-treated plants. Oxidative stress mitigation, increase in osmolytes, changes in sterols and terpenes composition, as well as the less expected increase in glucosinolates were also observed in biostimulant-treated plants grown under saline conditions. The present study proves that the application of plant-derived protein hydrolysate increases plant performance when plants are grown under salinity conditions. The most favorable metabolic profile was obtained when biostimulant was applied to both roots and leaves.

BACKGROUND Leaves of artichoke (Cynara cardunculus L. subsp. scolymus (L.) Hegi) and cardoon (Cynara cardunculus L. var. altilis DC) are traditionally used as herbal medicine. Moderate salt stress could enhance antioxidant activity and phytochemicals in leaves. The aim of this study was to evaluate the effect of chloride salts (NaCl, KCl and CaCl2) on biomass production, mineral composition, phenolic and flavonoid contents and antioxidant activity in leaves of artichoke and cardoon grown in a floating system. RESULTS In both crops, NaCl and KCl treatments reduced biomass production, while similar values were recorded in CaCl2 and control treatments. In both crops, KCl treatment enhanced total phenolic and flavonoid contents, antioxidant activity and target polyphenols in leaves harvested at 48, 82 and 105 days after sowing (DAS), while leaf quality was improved by NaCl and CaCl2 treatments only at 82 and 105 DAS. Irrespective of salinity, leaves of cardoon had higher total phenolic and flavonoid contents, antioxidant activity and target polyphenols than those of artichoke. CONCLUSION The results showed that application of KCl can be considered an effective way to produce high-quality leaves of artichoke and cardoon during the whole cropping cycle, although resulting in a 30% reduction in plant biomass.

The primary objective of this work was to identify, under laboratory conditions, the route of infection and hemogram of Dysdercus cingulatus (Fab.) adults by Metarhizium anisopliae. The infection process in D. cingulatus by M. anisopliae involved the conidia adherence to the host cuticle and germination after 24 h post-infection, accompanied by falling of bristles. The subsequent step, within 24–48 h post-infection, comprised penetration of fungus through spiracles, root of bristles, hemolymph, and the three dorsal sacs. Subsequently, within 72–96 h post-infection, the fungus penetrated into trachea and sacs, then emerged on cuticular surface and was found to be maximum in hemolymph. A great decrease in hemocytes count was observed within 96 h from infection. The hemosomic index (HSI) decreased gradually as the incubation period increased.

Cynara is a relatively small genus comprising two important crops: globe artichoke (C. cardunculus L. subsp. scolymus (L.) Fiori) and cultivated cardoon (C. cardunculus L. var. altilis DC.). The chemical components of artichoke leaves have been studied extensively and have been found to be a rich source of polyphenolic compounds. Nowadays, there is an increasing interest in the hydroponic floating trays system due to the advantage of cultivation of globe artichoke for leaf biomass production with shorter cycles. Three artichoke (‘Romolo’, ‘Violetto di Provenza’ and ‘Violetto di Romagna’) and three cultivated cardoon (‘Bianco Avorio’, ‘Bianco Gigante Inerme’ and ‘Gigante di Romagna’) genotypes were evaluated for their leaf dry biomass and major polyphenols. The highest leaf dry biomass was recorded in the three genotypes of cardoon followed by the two artichoke genotypes ‘Romolo’ and ‘Violetto di Provenza’. The major polyphenols present in the leaf were chlorogenic acid and cynarin, followed by luteolin, whereas apigenin was found in trace quantities. The highest concentration of chlorogenic acid was observed in ‘Violetto di Provenza’, ‘Violetto di Romagna’ and ‘Bianco Avorio’, whereas the highest luteolin concentration was found in the cardoon genotypes ‘Bianco Avorio Gigante di Romagna’. Data showed that the hydroponic floating tray is a suitable system for biomass production of globe artichoke and cultivated cardoon. They also suggest that specific genotypes should be selected to obtain the desired nutritional features.

Three greenhouse experiments were carried out to compare the responses of Aloe arborescens and Aloe barbadensis with organic fertilization (standard or reduced fertilization level), arbuscular mycorrhiza [with AM(+AM) or without AM (–AM)], and salinity (1 or 80mM NaCl) in terms of plant growth, leaf yield, mineral composition, and nutraceutical value. In all experiments, the yield of fresh leaves was significantly higher by 320%, 252%, and 72%, respectively, in A. barbadensis in comparison with A. arborescens. Doubling the fertilizer dose, plant growth parameters increased, but the bioactive compounds were negatively affected. The highest antioxidant activity was recorded with A. barbadensis using both fertilization regimes, whereas the highest values of anthraquinones aloin were observed in A. barbadensis using a reduced fertilization regime and when plants were inoculated with AM fungi. b-polysaccharide concentration was significantly higher in A. barbadensis in comparison with A. arborescens and was increased by 33%when plants were inoculated with AM fungi. In both Aloe species, increasing the salinity decreased the leaf freshweight and total dry biomass but increased the aloin and b-polysaccharides content by 66% and 21%, respectively. The results suggest that cultural practices such as organic fertilization, inoculation with AM fungi, and irrigation with saline water can represent effective tools to achieve a more favorable phytochemical profile.

The curative and therapeutic effects of Aloe plants have mostly been ascribed to anthraquinones such as aloin, and to some characteristic b-polysaccharides. Although the actual concentration of these bioactives in Aloe plants has not yet been fully clarified, it was expected that plant species, age and growth conditions would play an important role. The aim of this work was to investigate the relationship between species, light intensity and the content of bioactives in Aloe arborescens Mill. and Aloe vera (L.) Burm.f.Aloin was determined by liquid chromatography tandem mass spectrometry: Its concentration was higher in the leaves of younger plants and there was more in A. vera than in A. arborescens. The content of b-polysaccharides was determined colorimetrically after binding with Congo Red dye. The results were not affected by plant age, and oncentrations were higher in A. vera than in A. arborescens. Finally, even though the type of tunnel (and therefore light spectrum) under which plants were grown seemed to have no effect on the content of bioactives, the plants grown under reduced light intensities had significantly lower aloin and b-polysaccharides concentrations.

Flavonoids are the most common antioxidant compounds produced in plants. In this study, two wild types and two independent mutants of Medicago truncatula with altered anthocyanin content in leaves were characterized at the phenotype, metabolite profile, gene structure and transcript levels. Flavonoid profiles showed conserved levels of dihydroflavonols, leucoanthocyanidins and flavonols, while anthocyanidin, anthocyanin and isoflavone levels were lower in themutants (up to 90% less) comparedwith the wild types. Genes encoding key enzymes of the anthocyanin pathway and transcriptional factors were analyzed by RTPCR. Genes involved in the later steps of the anthocyanin pathway (dihydrokaempferol reductase 2, UDPglucose: anthocyanin 3-O-glucosyltransferase and glutathione S-transferase) were found under-expressed in both mutants. Dihydrokaempferol reductase 1 was downregulated two-fold in the anthocyanin-less mutant while the UDP-glucose:anthocyanin 5-O-glucosyltransferase was strongly repressed only in the mutant with low pigmentation, suggesting a different regulation in the two genotypes. The common feature was that the first enzymes of the flavonoid biosynthesis pathway were not altered in rate of expression. A very high reduction in transcript accumulation was also found for two homologous R2R3 MYB genes, namely MtMYBA and AN2, suggesting that these genes have a role in anthocyanin accumulation in leaves. More evidence was found on analyzing their nucleotide sequence: several SNPs, insertions and deletions in the coding and non-coding regions of both MYB genes were found between mutants and wild types that could influence anthocyanin biosynthesis. Moreover, a subfamily of eight MYB genes with a high homology to MtMYBA was discovered in tandem on chromosome 5 of M. truncatula.

BACKGROUND: Cynara cardunculus is a species native to the Mediterranean basin. It includes globe artichoke and cultivated cardoon as well as their progenitor wild cardoon. The species is a source of biophenols, and its leaf extracts have been widely used in herbal medicine as hepatoprotectors and choleretics since ancient times. The aim of this study was to determine the effect of increasing the level of salinity in the nutrient solution (1 or 30 mmol L−1 NaCl) on biomass production, mineral composition, radical-scavenging activity, caffeoylquinic acids and flavonoids in three artichoke (‘Romolo’, ‘Violetto di Provenza’ and ‘Violetto di Romagna’) and three cultivated cardoon (‘Bianco Avorio’, ‘Bianco Gigante Inerme’ and ‘Gigante di Romagna’) cultivars grown in a floating system. RESULTS: Increased salinity in the nutrient solution decreased the leaf dry biomass and leaf number of artichoke and cultivated cardoon cultivars. Salinity reduced macro- and microelement accumulation in leaves (e.g. N, K, Ca, Mg, Fe, Mn and B) but improved their antioxidant activity, total polyphenols, chlorogenic acid, cynarin and luteolin. The cultivated cardoons, especially ‘Bianco Avorio’ and ‘Gigante di Romagna’, showed higher biomass and leaf number than those observed in artichoke genotypes. ‘Violetto di Provenza’ exhibited the highest content of chlorogenic acid, closely followed by ‘Violetto di Romagna’, whereas for cynarin content the highest values were recorded in ‘Violetto di Provenza’, ‘Bianco Avorio’ and ‘Gigante di Romagna’. The highest content of luteolin was recorded in ‘Gigante di Romagna’ and ‘Bianco Avorio’, while the highest content of apigenin was observed in ‘Gigante di Romagna’. CONCLUSION: The results showed that the floating system could be considered an effective tool to improve quality aspects through proper management of the salt concentration in the nutrient solution. They also suggest that specific cultivars should be selected to obtain the desired profile of

A greenhouse experiment was conducted in Summer and Fall 2011 at the experimental farm of Tuscia University, central Italy, to study the effect of nutrient solution concentration (4, 20, 36, 52, or 68 mequiv·LL1) on biomass production, mineral composition, and concentrations of the major polyphenols in ‘Romolo’ artichoke and ‘Bianco Avorio’ cardoon grown in a floating system. Leaf dry biomass, leaf number, and macroelement concentrations (nitrogen, potassium, calcium, and magnesium) of artichoke and cardoon increased in response to an increase in the nutrient solution concentration, whereas an opposite trend was observed for the total polyphenols,phenolic acids (chlorogenic acid, cynarin, and caffeic acid), and the flavonoid luteolin. Artichoke and cardoon gave maximum biomass production and leaf number at 45 and 54 mequiv·L-1, respectively. Cardoon showed higher biomass and leaf number (average 1.13 kg·mL2 and 14.0 n./plant, respectively) than those observed in artichoke (average 1.07 kg·m-2 and 12.7 n./plant, respectively). The chlorogenic acid, cynarin, caffeic acid, and luteolin concentrations were higher by 204%, 462%, 580%, and 445% in cardoon leaf tissue than in that of artichoke. An improvement of leaf quality (total polyphenols, phenolic acids, and flavonoids) was obtained at the expense of leaf yield through the use of lower fertilizer concentrations in the nutrient solution.

The interest on Aloe based natural products is fast growing during recent years, particularly regarding their nutraceutical and antimicrobial properties. However, the information available on this item is limited and discrepancies can be found in literature. In this work, the antimicrobial properties of Aloe barbadensis Miller and Aloe arborescens Miller dermal and inner gel leaf fractions on the growth of five microorganisms were studied. Generally, gram positive were more susceptible than gram negative microorganisms and a lower activity of all fractions against the beneficial Saccharomyces boulardii was observed. Albeit the antimicrobial effect of pure anthraquinones aloin and aloe emodin was confirmed, a higher activity was observed for the methanol/ethyl acetate extracts of epidermis and for the water extract of the gel. A synergistic effect of several compounds, additional to the anthraquinones considered, should therefore be supposed. Conclusively, the Aloe extracts had an antimicrobial activity which is strongly related to the plant species and leaf fraction considered and which is a function of the microorganism considered.

The method performance and matrix effect related to quantitative determination of pesticide residues was assessed after QuEChERS extraction and LC–MS–MS analysis. Dicloran, phosmet and phosmet-oxon, pirimiphos-methyl, and BNOA were analyzed in peach, apple, melon, cereals, tomato, and strawberry. The matrix effects, as well as recovery and process efficiencies, were determined for a fungicide, two insecticides, and a plant growth regulator. Crop samples are spiked either pre- or post-extraction, then the peak area was compared with the peak area in neat solvent. The mean recovery ranged from 73% to 98%, and repeatability (as RSD) was between 3% and 16%, depending on the compound and spiking level. The matrix effect occurred as ionic suppression and was found in the range of 5% to 22% depending on the compound. Recovery efficiencies were good and substantially comparable, being in the range of 93–96%. Although the suppression observed still appears to be acceptable considering the overall process efficiency, it seems evident that the matrix effect is important when a reliable quantitative method must be applied.

Aloe-based household preparations and commercial products are used worldwide as a source of nutraceutical compounds, among which anthraquinones and acemannan are the most known. However, it is reported that improper storage conditions could lead to significant degradation processes, resulting in a low content of active substances. The aim of this work was to study the stability of aloin and â-polysaccharides in aloe-based products during storage, as a function of temperature and chemical agents added. Generally, aloin degradation in whole leaf homogenate was fast, and neither ascorbate nor the antimicrobial agents could increase stability; a lower temperature slightly improved stability, (DT50 up to 26 days at +4°C). Regarding the stability of â-polysaccharides, a strong influence of the storage temperature was observed, while antimicrobial agents did not show significant reduction of degradation. For both compounds, household and commercial products were significantly more stable.

Pirimiphos methyl is one of the most used compounds among insecticides and acaricides, against pests in post harvest application to cereals, even if it seems to be persistent; however, the milling process could likely represent a phase in which residues significantly decrease. The aim of this work was to comparatively assess the persistence of pirimiphos methyl residues in wheat and oat, after post harvest spray application, and to assess the fate of residues during the processing, by evaluating pirimiphos methyl contamination level in different milling fractions. An analytical method, based on a slightly modified QuEChERS extraction followed by liquid chromatography tandem mass spectrometry (LC-MS/MS) determination was validated: mean recovery was in the range 73% to 92% depending on the spiking level, and precision as RSD ranged from 11% to 16%). The analysis of treated samples revealed that pirimiphos methyl residues were highly persistent: as average, the insecticide persisted at 89% (ranging from 65% in bread making wheat to 107% in oat) after 42 weeks of storage. Furthermore, no differences could be observed between wheat, durum wheat and oat. As far as the impact of the milling process on residues is concerned, pirimiphos methyl contamination was significantly reduced during both cleaning and processing: the insecticide residues in flour were in the range 4-5% of initial contamination, and most of the contamination was related to outer kernel fractions.