Carbohydrate determination in honey samples by ion chromatography-mass spectrometry (HPAEC-MS).

Honey is a complex mixture of carbohydrates, in which the monosaccharides glucose and fructose are the most abundant compounds. Currently, more than 20 oligosaccharides have been identified in different varieties of honey normally at quite low concentration. A method was developed and validated using high-performance anion-exchange chromatography coupled to a mass spectrometry detector to investigate the composition of carbohydrates in honey samples. The method was tested for linearity range, trueness, instrumental and method detection and quantification limits, repeatability, and reproducibility. It was applied to determine seven monosaccharides, eight disaccharides, four trisaccharides, and one tetrasaccharide in various honey samples. The present work describes the composition of sugars in unifloral, multifloral, and some honeydew honey, which were produced and collected by beekeepers in the Trentino Alto-Adige region. Statistical techniques have been used to establish a relationship based on levels of carbohydrates among different Italian honey. The results emphasize that mono- and oligosaccharide profiles can be useful to discriminate different honeys according to their floral characteristics and inter-annual variability.

Evaluation of antimicrobial activity of Italian honey for wound healing application in veterinary medicine.

INTRODUCTION: Honey as a topical treatment for infected wounds dates back to ancient times. However, few studies have been reported concerning the medical properties of Italian honey. In this study, the microbial contamination, the antimicrobial activity and the antibiotic residues of 6 different varieties of Piedmont honeys were evaluated. The antimicrobial activity of honeys was tested by agar well diffusion method and 1 honey for each variety has been selected and tested by broth micro-dilution test to determine Minimum Inhibitory Concentrations (MICs) and evaluated by Minimum Bactericidal Concentrations (MBCs). The honeys with a high level of antibacterial activity were analyzed for the presence of tetracyclines, sulfonamides and macrolide residues. The agar well diffusion method showed the greatest antimicrobial activity for honeydew, chestnut and lime tree honeys. The MICs and MBCs identified the close similarity to the medical manuka honey of honeydew, polyfloral and chestnut honey. The levels of antibiotic residues on these honeys were below the limit of quantification. Based on our results the Italian variety of honeydew showed the best antimicrobial activity and can be considered for the treatment of infected wounds in animals.

INTRODUCTION: L'utilisation du miel pour le traitement des plaies infectées remonte à loin dans l'antiquité. Dans le présent travail, on étudie les contaminations microbiennes, l'activité antimicrobienne et les résidus d'antibiotiques dans 6 sortes de miels différentes provenant du Piémont. L'activité antimicrobienne a été mesurée au moyen d'une méthode de diffusion sur gel d'agar et un échantillon de chaque sorte de miel a été examiné quant à sa concentration minimale inhibitrice (CMI) et sa concentration minimale bactéricide (CMB) au moyen d'un test de micro-dilution. Les échantillons présentant une haute activité antibactérienne ont été analysés quant à la présence de tétracycline, de sulfamidés et de macrolides. Au test de diffusion sur agar, le miel de miellat ainsi que ceux de châtaignier et de tilleul ont démontré la plus grande activité antimicrobienne. Les CIM et CBM permettent de reconnaitre une grande similitude entre les miels de miellat, de nectar et de tilleul avec le miel de Manuka utilisé à des fins thérapeutiques. Les résidus d'antibiotiques de ces échantillons se situaient en dessous des limites de détection. Sur la base de ces constatations, les divers miels de miellat italiens présentent la plus grande activité antimicrobienne et peuvent être utilisés pour le traitement de plaies infectées chez les animaux.

Exploratory comparison of flower visiting behavior and pollination ability of mason bees, bumble bees, and honey bees.

This study explored the flower visiting behaviors and pollination abilities of mason bees (Osmia excavata Alfken (Hymenoptera: Megachilidae)), bumble bees (Bombus terrestris (Linnaeus, 1758) (Hymenoptera: Apidae)), and Italian honey bees (Apis mellifera ligustica Spinola (Hymenoptera: Apidae)) in apple orchards in early spring in Jinan (located in the central region of Shandong) and Yantai (located in the Peninsula of Shandong). We compared the pollen collection patterns, flower visiting behavior, flying speed, and effects on apple pollination of the 3 types of bees. The frequencies of flower visits were significantly higher for mason bees (12.89/min in Jinan and 10.63/min in Yantai) than bumble bees and Italian honey bees in the 2 regions. The single flower residence times were significantly higher for Italian honey bees (8.22 s in Jinan and 9.43 s in Yantai), but Italian honey bees were most affected by the climate. The 3 bees differed significantly in terms of the amount of apple pollen collected and their effects on the fruit setting rate in apples (mason bees > bumble bees > Italian honey bees). The results showed that the mason bee was the most suitable pollinating species for spring apple orchards; Bumble bees were more suitable as alternative pollinators during cloudy and low temperatures; Italian honey bees were able to take advantage of their large number of worker bees in sunny and warm weather. Compared to individual bee species, a combination of 2 or 3 species of bees might be more advantageous in dealing with complex and variable weather conditions.

Characterization of Botanical Origin of Italian Honey by Carbohydrate Composition and Volatile Organic Compounds (VOCs).

Honey is a natural sweetener constituted by numerous macro- and micronutrients. Carbohydrates are the most representative, with glucose and fructose being the most abundant. Minor honey components like volatile organic compounds (VOCs), minerals, vitamins, amino acids are able to confer honey-specific properties and are useful to characterize and differentiate between honey varieties according to the botanical origin. The present work describes the chemical characterization of honeys of different botanical origin (multifloral, acacia, apple-dandelion, rhododendron, honeydew, and chestnut) produced and collected by beekeepers in the Trentino Alto-Adige region (Italy). Melissopalynological analysis was conducted to verify the botanical origin of samples and determine the frequency of different pollen families. The carbohydrate composition (fourteen sugars) and the profile of VOCs were evaluated permitting to investigate the relationship between pollen composition and the chemical profile of honey. Statistical analysis, particularly partial least squares discriminant analysis (PLS-DA), demonstrates the importance of classifying honey botanical origin on the basis of effective pollen composition, which directly influences honey's biochemistry, in order to correctly define properties and value of honeys.