Elemental Fingerprinting of Pecorino Romano and Pecorino Sardo PDO: Characterization, Authentication and Nutritional Value.

Sardinia, located in Italy, is a significant producer of Protected Designation of Origin (PDO) sheep cheeses. In response to the growing demand for high-quality, safe, and traceable food products, the elemental fingerprints of Pecorino Romano PDO and Pecorino Sardo PDO were determined on 200 samples of cheese using validated, inductively coupled plasma methods. The aim of this study was to collect data for food authentication studies, evaluate nutritional and safety aspects, and verify the influence of cheesemaking technology and seasonality on elemental fingerprints. According to European regulations, one 100 g serving of both cheeses provides over 30% of the recommended dietary allowance for calcium, sodium, zinc, selenium, and phosphorus, and over 15% of the recommended dietary intake for copper and magnesium. Toxic elements, such as Cd, As, Hg, and Pb, were frequently not quantified or measured at concentrations of toxicological interest. Linear discriminant analysis was used to discriminate between the two types of pecorino cheese with an accuracy of over 95%. The cheese-making process affects the elemental fingerprint, which can be used for authentication purposes. Seasonal variations in several elements have been observed and discussed.

An Analytical Protocol for the Differentiation and the Potentiometric Determination of Fluorine-Containing Fractions in Bovine Milk.

Free fluoride ions are effective in combating caries in children, and their supplementation in milk has been widely used worldwide for this purpose. Furthermore, it is known that ionic fluoride added to milk is distributed among its components, but little is known about their quantitative relationships. This is likely due to the absence of an analytical protocol aimed at differentiating and quantifying the most important forms of fluorine present in milk. For the first time, a comprehensive protocol made up of six potentiometric methods devoted to quantifying the most important fractions of fluorine in milk (i.e., the free inorganic fluoride, the inorganic bonded fluorine, the caseins-bonded fluorine, the whey-bonded fluorine, the lipid-bonded fluorine, and the total fluorine) has been developed and tested on real samples. Four of the six methods of the procedure are original, and all have been validated in terms of limit of detection and quantification, precision, and trueness. The data obtained show that 9% of all fluorine was in ionic form, while 66.3% of total fluorine was bound to proteins and lipids, therefore unavailable for human absorption. Beyond applications in dental research, this protocol could be extended also to other foods, or used in environmental monitoring.

Influence of irrigation methods on arsenic speciation in rice grain.

Although the bioaccumulation of arsenic (As) in rice grains is a global health issue, its speciation is not less worrying. Despite the ascertained effectiveness of the intermittent irrigation methods in minimizing the amount of total As in rice, knowledge of its influence on the As speciation has been insufficient so far. Hence, this contribution was aimed to measure the concentrations of As(III), As(V), dimethylarsinic acid (DMA), and monomethylarsonic acid (MMA) in grains from twenty-six different rice genotypes irrigated either with continuous flooding (CF), periodic saturation (SA) or sprinkler irrigation (SP). In CF-irrigated rice, As(III) and DMA prevailed in roughly equal amounts, only As(III) was found in SA-irrigated rice, whereas As(V) was largely predominant on As(III) in SP-irrigated rice. Organoarsenic species were below the limits of detection (LoD) in rice irrigated by intermittent methods. Principal component analysis (PCA) explained the influence of the irrigation method on the total amount of As, its chemical species, and their correlation. Furthermore, PCA showed also significant differences in As speciation as a function of the rice genotype, whereas no differences were found among Indica and Japonica subspecies.

Assessment and validation of ICP-MS and IC-ICP-MS methods for the determination of total, extracted and speciated arsenic. Application to samples from a soil-rice system at varying the irrigation method.

Food is the major route of arsenic (As) intake for humans, and rice is the staple food for more than half of the world's population. Unfortunately, rice bioaccumulates large amounts of As from the paddy field, and the toxicity of this element in the kernel is closely linked to its chemical form. Therefore, it is of the utmost importance to have access to an integrated set of analytical methods, capable of measuring the concentration of As in its various chemical forms in soil and rice. Hence, the principal aim of this study was to assess and validate a group of inductively coupled plasma - mass spectrometry (ICP-MS) and IC-ICP-MS (IC, Ionic Chromatography) methods designed to measure the amount of the total or extracted As and its main chemical species (As(III), As(V), monomethylarsonic acid, MMA, and dimethylarsinic acid, DMA) in flours of rice grain and in soils. Great attention has been given to the assessment and the optimization of extraction methods of As species from these matrices. No appreciable interconversion among As species has been observed using an aqueous solution 1 mol dm-3 of phosphoric acid and 0.5 mol dm-3 of L (+)-ascorbic acid for the extraction from soils, and an aqueous solution 0.2% (w/v) of nitric acid for the extraction from rice flour. Validation has been successfully accomplished in terms of limit of detection, limit of quantification, linearity and accuracy. In addition to many certified reference materials, these methods have been tested on real samples of soils and rice grains of the Aleramo genotype obtained through traditional or intermittent irrigation methods. Data obtained revealed the critical role of the intermittent irrigation methods in determining the nature and the amount of the As chemical species in rice grains as well as in soils. As(V) is the only species found in soil irrigated by sprinkling, while the most toxic As(III) dominates in soil irrigated by continuous flooding. On the other hand, the most abundant species found in continuously flooded Aleramo rice grains are As(III) and - mostly - DMA, whereas As(V), less toxic than As(III), represents 60% of the total inorganic compounds measured in sprinkler-irrigated rice. Lastly, the total amount of As measured in this rice is 3.8% of that measured in rice irrigated by continuous flooding.

Multi-Elemental Analysis as a Tool to Ascertain the Safety and the Origin of Beehive Products: Development, Validation, and Application of an ICP-MS Method on Four Unifloral Honeys Produced in Sardinia, Italy.

Despite unifloral honeys from Sardinia, Italy, being appreciated worldwide for their peculiar organoleptic features, their elemental signature has only partly been investigated. Hence, the principal aim of this study was to measure the concentration of trace and toxic elements (i.e., Ag, As, Ba, Be, Bi, Cd, Co, Cr, Cu, Fe, Hg, Li, Mn, Mo, Ni, Pb, Sb, Sn, Sr, Te, Tl, V, and Zn) in four unifloral honeys produced in Sardinia. For this purpose, an original ICP-MS method was developed, fully validated, and applied on unifloral honeys from asphodel, eucalyptus, strawberry tree, and thistle. Particular attention was paid to the method's development: factorial design was applied for the optimization of the acid microwave digestion, whereas the instrumental parameters were tuned to minimize the polyatomic interferences. Most of the analytes' concentration ranged between the relevant LoDs and few mg kg-1, while toxic elements were present in negligible amounts. The elemental signatures of asphodel and thistle honeys were measured for the first time, whereas those of eucalyptus and strawberry tree honeys suggested a geographical differentiation if compared with the literature. Chemometric analysis allowed for the botanical discrimination of honeys through their elemental signature, whereas linear discriminant analysis provided an accuracy level of 87.1%.

A Friendly Complexing Agent for Spectrophotometric Determination of Total Iron.

Iron, one of the most common metals in the environment, plays a fundamental role in many biological as well as biogeochemical processes, which determine its availability in different oxidation states. Its relevance in environmental and industrial chemistry, human physiology, and many other fields has made it necessary to develop and optimize analysis techniques for accurate determination. Spectrophotometric methods are the most frequently applied in the analytical determination of iron in real samples. Taking advantage of the fact that desferrioxamine B, a trihydroxamic acid used since the 1970s in chelation therapy for iron overload treatment, forms a single stable 1:1 complex with iron in whichever oxidation state it can be found, a smart spectrophotometric method for the analytical determination of iron concentration was developed. In particular, the full compliance with the Lambert-Beer law, the range of iron concentration, the influence of pH, and the interference of other metal ions have been taken into account. The proposed method was validated in terms of LoD, LoQ, linearity, precision, and trueness, and has been applied for total iron determination in natural water certified material and in biological reference materials such as control human urine and control serum.

Electrochemical Determination of the "Furanic Index" in Honey.

5-(hydroxymethyl)furan-2-carbaldehyde, better known as hydroxymethylfurfural (HMF), is a well-known freshness parameter of honey: although mostly absent in fresh samples, its concentration tends to increase naturally with aging. However, high quantities of HMF are also found in fresh but adulterated samples or honey subjected to thermal or photochemical stresses. In addition, HMF deserves further consideration due to its potential toxic effects on human health. The processes at the origin of HMF formation in honey and in other foods, containing saccharides and proteins-mainly non-enzymatic browning reactions-can also produce other furanic compounds. Among others, 2-furaldehyde (2F) and 2-furoic acid (2FA) are the most abundant in honey, but also their isomers (i.e., 3-furaldehyde, 3F, and 3-furoic acid, 3FA) have been found in it, although in small quantities. A preliminary characterization of HMF, 2F, 2FA, 3F, and 3FA by cyclic voltammetry (CV) led to hypothesizing the possibility of a comprehensive quantitative determination of all these compounds using a simple and accurate square wave voltammetry (SWV) method. Therefore, a new parameter able to provide indications on quality of honey, named "Furanic Index" (FI), was proposed in this contribution, which is based on the simultaneous reduction of all analytes on an Hg electrode to ca. -1.50 V vs. Saturated Calomel Electrode (SCE). The proposed method, validated, and tested on 10 samples of honeys of different botanical origin and age, is fast and accurate, and, in the case of strawberry tree honey (Arbutus unedo), it highlighted the contribution to the FI of the homogentisic acid (HA), i.e., the chemical marker of the floral origin of this honey, which was quantitatively reduced in the working conditions. Excellent agreement between the SWV and Reverse-Phase High-Performance Liquid Chromatography (RP-HPLC) data was observed in all samples considered.

ICP-MS Determination of 23 Elements of Potential Health Concern in Liquids of e-Cigarettes. Method Development, Validation, and Application to 37 Real Samples.

The lack of interest in the determination of toxic elements in liquids for electronic cigarettes (e-liquids) has so far been reflected in the scarce number of accurate and validated analytical methods devoted to this aim. Since the strong matrix effects observed for e-liquids constitute an exciting analytical challenge, the main goal of this study was to develop and validate an ICP-MS method aimed to quantify 23 elements in 37 e-liquids of different flavors. Great attention has been paid to the critical phases of sample pre-treatment, as well as to the optimization of the ICP-MS conditions for each element and of the quantification. All samples exhibited a very low amount of the elements under investigation. Indeed, the sum of their average concentration was of ca. 0.6 mg kg-1. Toxic elements were always below a few tens of a µg per kg-1 and, very often, their amount was below the relevant quantification limits. Tobacco and tonic flavors showed the highest and the lowest concentration of elements, respectively. The most abundant elements came frequently from propylene glycol and vegetal glycerin, as confirmed by PCA. A proper choice of these substances could further decrease the elemental concentration in e-liquids, which are probably barely involved as potential sources of toxic elements inhaled by vapers.

Classification of Unifloral Honeys from SARDINIA (Italy) by ATR-FTIR Spectroscopy and Random Forest.

Nowadays, the mislabeling of honey floral origin is a very common fraudulent practice. The scientific community is intensifying its efforts to provide the bodies responsible for controlling the authenticity of honey with fast and reliable analytical protocols. In this study, the classification of various monofloral honeys from Sardinia, Italy, was attempted by means of ATR-FTIR spectroscopy and random forest. Four different floral origins were considered: strawberry-tree (Arbutus Unedo L.), asphodel (Asphodelus microcarpus), thistle (Galactites tormentosa), and eucalyptus (Eucalyptus calmadulensis). Training a random forest on the infrared spectra allowed achieving an average accuracy of 87% in a cross-validation setting. The identification of the significant wavenumbers revealed the important role played by the region 1540-1175 cm-1 and, to a lesser extent, the region 1700-1600 cm-1. The contribution of the phenolic fraction was identified as the main responsible for this observation.

Tuning of the Amount of Se in Rice (Oryza sativa) Grain by Varying the Nature of the Irrigation Method: Development of an ICP-MS Analytical Protocol, Validation and Application to 26 Different Rice Genotypes.

The amount of specific trace elements like selenium (Se) may be of health concern for humans if contained in too high (or low) quantities in staple foods like rice. Among the attempts aimed to optimize the Se concentration in rice, only few studies have been focused on the use of irrigation methods other than continuous flooding. Since intermittent irriguous methods, like sprinkler and saturation, have found to be effective in modifying the bioaccumulation of arsenic and cadmium in rice kernels, the main goal of this study is to measure the amount of the total Se contained in grains of 26 rice genotypes cultivated for two consecutive agrarian vintages in the same open field and with the same water, but differently irrigated with continuous flooding, sprinkler or saturation. To do this, an original and validated ICP-MS method has been developed. The validation parameters accounted for a high sensitivity and accuracy. Sprinkler irrigation is able to reduce in the average of 90% the amount of total Se in kernels in comparison to values measured in rice irrigated with continuous flooding. In conclusion, different irrigation techniques and rice genotypes seem to be valuable tools in order to allow in the future the customized modulation of the Se concentration in rice grain according to the needs of the various populations.

Strawberry-Tree Honey Induces Growth Inhibition of Human Colon Cancer Cells and Increases ROS Generation: A Comparison with Manuka Honey.

Honey is a natural product known to modulate several biological activities including cancer. The aim of the present study was to examine the phytochemical content and the antioxidant activity of Strawberry tree (Arbutus unedo) honey (STH) and its cytotoxic properties against human colon adenocarcinoma (HCT-116) and metastatic (LoVo) cell lines in comparison with Manuka (Leptospermum scoparium) honey (MH). Several unifloral STH and MH were analyzed for their phenolic, flavonoid, amino acid and protein contents, as well as their radical scavenging activities. STH from the Berchidda area showed the highest amount of phenolic, flavonoid, amino acid and protein content, and antioxidant capacity compared to MH. Both STH and MH induced cytotoxicity and cell death in a dose- and time-dependent manner in HCT-116 and LoVo cells, with less toxicity on non-cancer cells. Compared to MH, STH showed more effect at lower concentrations on HCT-116 and LoVo cells. In addition, both honeys increased intracellular reactive oxygen species (ROS) generation. In HCT-116 cells, STH and MH induced similar ROS production but in LoVo cells STH induced a higher percentage of ROS compared to MH. Our results indicate that STH and MH can induce cell growth inhibition and ROS generation in colon adenocarcinoma and metastatic cells, which could be due to the presence of phytochemicals with antioxidant properties. These preliminary results are interesting and suggest a potential chemopreventive action which could be useful for further studies in order to develop chemopreventive agents for colon cancer.

Gas chromatography analysis of major free mono- and disaccharides in milk: Method assessment, validation, and application to real samples.

Saccharides are functional constituents of milk. Although d-lactose represents almost the totality of the saccharides in the milk, minor species, like d-glucose, d-galactose, myo-inositol and, as a result of severe thermal treatments, monosaccharides like d-tagatose, are also detectable. Although chromatography has been the main analytical approach used for accomplishing this task, quite surprisingly a validated gas chromatographic method aimed at the simultaneous determination of these compounds is still needed. Hence, our contribution is devoted to fill this gap. After the optimization of clean-up and derivatization (conversion of saccharides in their trimethyl silyl ethers) steps, the adoption of a highly cross-linked silphenylene stationary phase permitted to obtain high resolution and a fast chromatographic run. Validation was accomplished in terms of limit of detection, limit of quantification, linearity, precision, and trueness. The accuracy of the method was successfully tested on a number of partially skimmed milk samples. Excellent limits of detection for all analytes make this method eligible, also with respect to a gas chromatographic/mass spectrometry approach, for routine analysis and quality control in the dairy industries.

Recent Advances in the Analysis of Phenolic Compounds in Unifloral Honeys.

Honey is one of the most renowned natural foods. Its composition is extremely variable, depending on its botanical and geographical origins, and the abundant presence of functional compounds has contributed to the increased worldwide interest is this foodstuff. In particular, great attention has been paid by the scientific community towards classes of compounds like phenolic compounds, due to their capability to act as markers of unifloral honey origin. In this contribution the most recent progress in the assessment of new analytical procedures aimed at the definition of the qualitative and quantitative profile of phenolic compounds of honey have been highlighted. A special emphasis has been placed on the innovative aspects concerning the extraction procedures, along with the most recent strategies proposed for the analysis of phenolic compounds. Moreover, the centrality of validation procedures has been claimed and extensively discussed in order to ensure the fitness-for-purpose of the proposed analytical methods. In addition, the exploitation of the phenolic profile as a tool for the classification of the botanical and geographical origin has been described, pointing out the usefulness of chemometrics in the interpretation of data sets originating from the analysis of polyphenols. Finally, recent results in concerning the evaluation of the antioxidant properties of unifloral honeys and the development of new analytical approaches aimed at measuring this parameter have been reviewed.

Genetic variation for the duration of pre-anthesis development in durum wheat and its interaction with vernalization treatment and photoperiod.

A recombinant inbred durum wheat population was grown under three contrasting regimes: long days following vernalization (LDV), long days without vernalization (LD), and short days following vernalization (SDV). The length of several pre-anthesis stages and the number of leaves and the phyllochron were measured. Different groups of genes were involved in determining the phenology in the three treatments, as demonstrated by a quantitative trait locus (QTL) analysis. The length of the period required to reach the terminal spikelet stage was correlated with the time to anthesis only in the case of LDV- and LD-grown plants where the timing of anthesis depended on the final leaf number. However, for SDV-grown plants, anthesis date was more dependent on the length of the period between the terminal spikelet stage and anthesis and was independent of leaf number. The involvement of the phyllochron in determining the duration of pre-anthesis development was also treatment-dependent. QTL mapping of the various flowering time associated traits uncovered some novel loci (such as those associated with the phyllochron), in addition to confirming the presence of several well-established loci.

Fluoride content in breast milk after the use of fluoridated food supplement. A randomized clinical trial.

PURPOSE: To evaluate if the intake of a fluoridated food supplement in breastfeeding mothers increases the fluoride concentration in breast milk. METHODS: A double-blind randomized placebo-controlled study was designed. Two groups of women were formed: a fluoride group (n = 112), using a non-sucrose food supplement containing fluoride (1,500 µg/l for each dose) and a control group (n = 116), using a non-sucrose food supplement without fluoride content. The women were followed for 6 weeks. Samples of breast milk were collected and analyzed using an ion-specific electrode. RESULTS: 85 women in the fluoride group and 83 in the control group concluded the trial. Fluoride concentrations in the two groups were statistically significantly different (515 µg/l in the fluoride and 476 µg/l in the control group P= 0.04) at the end of the experimental period. In the fluoride group, a statistically significant increment in fluoride concentration during the experimental period was also observed (from 468 ± 104 µg/l to 515 ± 105 µg/l). The use of a non-sucrose food supplement containing fluoride resulted in a significant increment in fluoride concentration in breast milk.

Portable NIR Spectroscopy to Simultaneously Trace Honey Botanical and Geographical Origins and Detect Syrup Adulteration.

Fraudulent practices concerning honey are growing fast and involve misrepresentation of origin and adulteration. Simple and feasible methods for honey authentication are needed to ascertain honey compliance and quality. Working on a robust dataset and simultaneously investigating honey traceability and adulterant detection, this study proposed a portable FTNIR fingerprinting approach combined with chemometrics. Multifloral and unifloral honey samples (n = 244) from Spain and Sardinia (Italy) were discriminated by botanical and geographical origin. Qualitative and quantitative methods were developed using linear discriminant analysis (LDA) and partial least squares (PLS) regression to detect adulterated honey with two syrups, consisting of glucose, fructose, and maltose. Botanical and geographical origins were predicted with 90% and 95% accuracy, respectively. LDA models discriminated pure and adulterated honey samples with an accuracy of over 92%, whereas PLS allows for the accurate quantification of over 10% of adulterants in unifloral and 20% in multifloral honey.

Mass Spectrometry Characterization of Honeydew Honey: A Critical Review.

Honeydew honey is produced by bees (Apis mellifera) foraging and collecting secretions produced by certain types of aphids on various parts of plants. In addition to exhibiting organoleptic characteristics that distinguish them from nectar honey, these honeys are known for their functional properties, such as strong antioxidant and anti-inflammatory activities. Despite their importance, they remain poorly characterized in comparison with flower honeys, as most studies on this subject are not only carried out on too few samples but also still focused on traditional chemical-physical parameters, such as specific rotation, major sugars, or melissopalynological information. Since mass spectrometry has consistently been a primary tool for the characterization and authentication of honeys, this review will focus on the application of these methods to the characterization of the minor fraction of honeydew honey. More specifically, this review will attempt to highlight what progress has been made so far in identifying markers of the authenticity of the botanical and/or geographical origin of honeydew honeys by mass spectrometry-based approaches. Furthermore, strategies devoted to the determination of contaminants and toxins in honeydew honeys will be addressed. Such analyses represent a valuable tool for establishing the level of food safety associated with these products. A critical analysis of the presented studies will identify their limitations and critical issues, thereby describing the current state of research on the topic.

Elemental Fingerprinting Combined with Machine Learning Techniques as a Powerful Tool for Geographical Discrimination of Honeys from Nearby Regions.

Discrimination of honey based on geographical origin is a common fraudulent practice and is one of the most investigated topics in honey authentication. This research aims to discriminate honeys according to their geographical origin by combining elemental fingerprinting with machine-learning techniques. In particular, the main objective of this study is to distinguish the origin of unifloral and multifloral honeys produced in neighboring regions, such as Sardinia (Italy) and Spain. The elemental compositions of 247 honeys were determined using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The origins of honey were differentiated using Principal Component Analysis (PCA), Linear Discriminant Analysis (LDA), and Random Forest (RF). Compared to LDA, RF demonstrated greater stability and better classification performance. The best classification was based on geographical origin, achieving 90% accuracy using Na, Mg, Mn, Sr, Zn, Ce, Nd, Eu, and Tb as predictors.

The role of irrigation techniques in arsenic bioaccumulation in rice (Oryza sativa L.).

The bioaccumulation of arsenic compounds in rice is of great concern worldwide because rice is the staple food for billions of people and arsenic is one of the most toxic and carcinogenic elements at even trace amounts. The uptake of arsenic compounds in rice comes mainly from its interaction with system soil/water in the reducing conditions typical of paddy fields and is influenced by the irrigation used. We demonstrate that the use of sprinkler irrigation produces rice kernels with a concentration of total arsenic about fifty times lower when compared to rice grown under continuous flooding irrigation. The average total amount of arsenic, measured by a fully validated ICP-MS method, in 37 rice grain genotypes grown with sprinkler irrigation was 2.8 ± 2.5 µg kg(-1), whereas the average amount measured in the same genotypes grown under identical conditions, but using continuous flooding irrigation was 163 ± 23 µg kg(-1). In addition, we find that the average concentration of total arsenic in rice grains cultivated under sprinkler irrigation is close to the total arsenic concentration found in irrigation waters. Our results suggest that, in our experimental conditions, the natural bioaccumulation of this element in rice grains may be completely circumvented by adopting an appropriate irrigation technique.

Laboratory enamel fluoride uptake from fluoride products.

PURPOSE: To evaluate the fluoride concentration in enamel after the use of different fluoride products and 48 hours after the cessation of fluoride use. METHODS: 16 enamel slabs were divided and treated for 15 days as following: Group A, with an amine fluoride toothpaste and mouthrinse (1400 and 250 mg/L(-1), respectively); Group B, with an amine fluoride toothpaste (1400 mg/L(-1)) and mouthrinse without fluoride; Group C, with a sodium fluoride toothpaste (1400 mg/L(-1)) and mouthrinse (250 mg/L(-1)). Chemical biopsy and multiple means were used to determine fluoride concentration. The data were statistically analyzed using the two-way ANOVA and Tukey HSD tests (P<0.05). RESULTS: After 15 days of fluoride product use, Group A samples had the highest fluoride uptake (0.19 microg mm(-2)) (P<0.05). 48 hours after the interruption of fluoride product usage, a higher fluoride concentration was found in Group A samples. Although all fluoride products led to an enamel uptake, amine fluoride products promoted the most effective long-term uptake.