Sviluppo e applicazione di metodi cromatografici per la determinazione quali-quantitativa di costituenti minoritari di prodotti d'alveare

All the products originating in the beehive are attractive ingredients for functional foods. Honey has been used since ancient times as part of traditional medicine although nowadays it is mainly used as a sweetener. The actual composition of honeys varies depending on many factors such as the pollen source, climate, environmental conditions and processing. Royal jelly is the exclusive food of queen honey bee. The chief components of royal jelly are water, proteins, carbohydrates, lipids, mineral salts and vitamins, whereas a large number of bioactive substances characterizes the minority composition. For these reasons royal jelly is commonly used like a dietary supplement. In the first part of this thesis, the typical profile of the free amino acids contained in strawberry-tree (Arbutus unedo L.) honey is reported. An optimized reversed-phase liquid chromatographic method with phenyl isothiocyanate precolumn derivatization was used. In the second part, a direct RP-HPLC method for the determination of furanic aldehydes and acids in honey is presented. Hypotheses relating to the formation of minority furanic compounds are also proposed. Finally, the assessment and validation of two chromatographic methods for the determination of water-soluble vitamins in honey and royal jelly is proposed. All the analytical methods were fully validated in terms of detection and quantification limits, precision, linearity and bias. They are all characterized by excellent analytical performances

Sviluppo e applicazione di metodi cromatografici per la determinazione quali-quantitativa di costituenti minoritari di prodotti d'alveare

All the products originating in the beehive are attractive ingredients for functional foods. Honey has been used since ancient times as part of traditional medicine although nowadays it is mainly used as a sweetener. The actual composition of honeys varies depending on many factors such as the pollen source, climate, environmental conditions and processing. Royal jelly is the exclusive food of queen honey bee. The chief components of royal jelly are water, proteins, carbohydrates, lipids, mineral salts and vitamins, whereas a large number of bioactive substances characterizes the minority composition. For these reasons royal jelly is commonly used like a dietary supplement. In the first part of this thesis, the typical profile of the free amino acids contained in strawberry-tree (Arbutus unedo L.) honey is reported. An optimized reversed-phase liquid chromatographic method with phenyl isothiocyanate precolumn derivatization was used. In the second part, a direct RP-HPLC method for the determination of furanic aldehydes and acids in honey is presented. Hypotheses relating to the formation of minority furanic compounds are also proposed. Finally, the assessment and validation of two chromatographic methods for the determination of water-soluble vitamins in honey and royal jelly is proposed. All the analytical methods were fully validated in terms of detection and quantification limits, precision, linearity and bias. They are all characterized by excellent analytical performances

Extraction and Analysis of Phenolic Compounds in Rice: A Review

Rice represents the main source of calorie intake in many world countries and about 60% of the world population include rice in their staple diet. Whole grain rice, also called brown rice, represent the unpolished version of the more common white rice including bran, germ, and endosperm. Many health-promoting properties have been associated to the consumption of whole grain rice and, for this reason, great attention has been paid by the scientific community towards the identification and the quantification of bioactive compounds in this food item. In this contribution, the last five years progresses in the quali-quantitative determination of phenolic compounds in rice have been highlighted. Special attention has been devoted to the most recent strategies for the extraction of the target compounds from rice along with the analytical approaches adopted for the separation, identification and quantification of phenolic acids, flavonoids, anthocyanins, and proanthocyanidins. More specifically, the main features of the “traditional” extraction methods (i.e., maceration, ultrasound-assisted extraction) have been described, as well as the more innovative protocols involving advanced extraction techniques, such as MAE (microwave-assisted extraction). The predominant role of HPLC in the definition of the phenolic profile has been examined also presenting the most recent results obtained by using mass spectrometry-based detection systems. In addition, the most common procedures aimed to the quantification of the total amount of the cited classes of phenolic compounds have been described together with the spectrophotometric protocols aimed to the evaluation of the antioxidant properties of rice phenolic extracts (i.e., FRAP, DPPH, ABTS and ORAC)

Portable NIR spectroscopy to simultaneously trace honey botanical and geographicl 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

Thermal degradation of red cabbage (Brassica oleracea L. var. Capitata f. rubra) anthocyanins in a water model extract under accelerated shelf-life testing

Red cabbage (RC) represents a source of anthocyanins acylated with hydroxycinnamic acids (HCA) that are described to enhance their stability. Nevertheless, data about their thermal degradation are still controversial. Our aim was to comprehensively analyse the degradation kinetics of individual RC anthocyanins in a model aqueous extract treated at 40 °C × 30 days to simulate severe but realistic storage conditions. Free anthocyanins and radical-scavenging capacity showed different kinetics. The results confirm the high stability of RC anthocyanins (t1/2: 16.4-18.4 days), although HPLC analyses of each molecule displayed distinct kinetics with t1/2 from 12.6 to 35.1 days. In particular, the sinapoyl acylation negatively affected the stability of the anthocyanins, while the forms monoacylated with glycosyl p-coumaric and ferulic acids exhibited higher stability. In conclusion, our results indicate that acylation is not a prerogative of stability, as this is instead more dependent on specific acylation patterns and the glycosylation of HCA

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

New Insights on Quality, Safety, Nutritional, and Nutraceutical Properties of Honeydew Honeys from Italy

Honeydew honey is less studied than nectar honey, although it is characterized by peculiar nutritional properties. This is mainly due to its challenging production, which leads to easy counterfeiting and difficult valorization. This contribution aims to provide a comprehensive characterization of the physico-chemical, palynological, functional, and food safety properties of a large sampling of honeydew honeys collected throughout Italy. The honeydew elements, conductivity, color, antioxidant properties, total polyphenol content, hydroxymethylfurfural, major and trace elements, toxic and rare earth elements, and pesticide residues were measured in 59 samples of honeydew honey from forest, eucalyptus, fir, oak, and citrus sources. Physico-chemical and antioxidant properties were unable to differentiate the botanical origin of Italian honeydew honeys. Similarly, the mineral composition did not vary significantly, whereas rare earth elements appeared to be promising markers for classifying their origin. Multivariate analysis allowed discriminating fir honeydews from the other varieties. Concerning safety aspects, pesticide residues were detected in 90% of the samples, with fir honeydews exhibiting the lowest contamination levels, probably due to its production in less industrialized areas. Acetamiprid and imidacloprid were the most prevalent pesticide residues, but their concentrations were below the limit indicated by the EFSA. These findings suggest the need for a continuous monitoring program for contaminants to ensure safety and to assess risk

Multi-level approach to screen tomato inbred lines for resilience to Ni-enriched soils and water deficit

Climate-driven increases in drought occurrence and the contamination of soils by heavy metals adversely affect tomato production both qualitatively and quantitatively. The aim of the present study was to investigate the responses of four inbred lines of Solanum lycopersicum to Ni toxicity and water deprivation. To evaluate the effects of Ni, we used two different growth approaches, in hydroponics and in soil, associating a morphological analysis of the lines with Ni and mineral nutrient quantification in both shoots and fruits. The effects of water stress were tested on germination capacity in vitro and on adult plants grown in soil. The responses of the different lines to water stress were assessed by physiological and phenotypic analyses, expression of droughtrelated genes and quantification of ABA. The multi-level approach allowed us to identify two lines, among the four investigated, as good candidates for future breeding programs due to their ability to accumulate less Ni and maintain fruit quality parameters and capacity to acclimate to repeated water stress

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 machinelearning 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 predictor

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