Stingless bees (Tribe Meliponini) are a diverse group of highly eusocial bees distributed throughout the tropics and subtropics. Trigona carbonaria honey, from Australia, was characterized by traditional physicochemical parameters (acidity, sugars, diastase, electrical conductivity, hydroxymethylfurfural, invertase, nitrogen, and water content) and other compositional factors (flavonoids, polyphenols, organic acids, and water activity), as well as total antioxidant capacity and radical scavenging activity. For the Australian T. carbonaria, the traditional analytical parameters were similar to those previously reported for neotropical stingless bee honey and confirm that honeys produced by Meliponini bees possess several physicochemical properties that are distinctly different from Apis mellifera honey, with higher values of moisture (26.5 +/- 0.8 g of water/100 g of honey), water activity (0.74 +/- 0.01), electrical conductivity (1.64 +/- 0.12 mS/cm), and free acidity (124.2 +/- 22.9 mEq/kg of honey) and a very low diastase activity (0.4 +/- 0.5 diastase number) and invertase activity (5.7 +/- 1.5 invertase number). The sugar spectrum was quite different from that of A. mellifera honey, with 20.3 +/- 2.9 g of maltose/100 g of honey. The values of pH (4.0 +/- 0.1), lactonic acidity (4.7 +/- 0.8 mEq/kg of honey), sucrose (1.8 +/- 0.4 g/100 g of honey), and fructose/glucose ratio (1.42 +/- 0.13) fell in the same ranges as those of A. mellifera honey. Citric (0.23 +/- 0.09) and malic (0.12 +/- 0.03) acid concentrations (in g/kg of honey) of T. carbonaria honeys were in the range described for A. mellifera honey. D-Gluconic was more concentrated (9.9 +/- 1.3 g/kg of honey), in the range of Italian Castanea, Thymus, Arbutus, and honeydew honeys. Flavonoid content was 10.02 +/- 1.59 mg of quercetin equivalents/100 g of honey, and polyphenol contents were 55.74 +/- 6.11 mg of gallic acid equivalents/100 g of honey. The antioxidant activity, expressed as percentage of 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) cation (ABTS(*+)) decolorization, was 233.96 +/- 50.95 microM Trolox equivalents, and free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH(*)) depletion was 48.03 +/- 12.58 equivalents of ascorbic acid. All reported values are averages +/- standard deviation. The antioxidant activity can represent an important added value for T. carbonaria honey, to initiate a medicinal approach for both nutritional and pharmaceutical applications, besides further physicochemical characterization.

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-A HPLC method with refractive index detection (RID) was developed for sugar determination in royal jelly (RJ). The method enables the determination of the three main sugars of royal jelly (fructose, glucose and sucrose), and maltose, which is sometimes present in RJ. The method ensures adequate sensitivity, quantitative recoveries, does not suffer from matrix interferences and shows good repeatability. It was used for the analysis of 97 RJ samples of different origin and the results were found to be in agreement with those reported in literature. The method is simple and suitable for a routine quality control of RJ sugar composition and represents an alternative to gas chromatographic methods, which require more complex purification and derivatisation steps. royal jelly / sugars / HPLC

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-A correlation was found between the measured refraction index of royal jelly and its water content as determined by vacuum oven drying. Twenty-seven different royal jelly samples were analysed for their water content by performing 24 hour vacuum drying at 48• C, obtaining values that covered almost the entire range reported in literature. The refraction index values for the same samples were measured using a thermostated Abbe refractometer. A simple linear relationship (R 2 = 0.96) between refraction index and water content was found proving the fitness of a refractometric measure for quality control purposes. The relationship provides estimates of water content that are similar to those resulting from the Wedmore equation (R 2 = 0.9999) used to estimate water content in honey. The refractometric evaluation of the water content provides sufficient reliability for the routine quality control of royal jelly and is faster and simpler than currently used methods.royal jelly / water / refractometer