Ferulic acid as major antioxidant phenolic compound of the Tetragonisca angustula honey collected in Vera Cruz - Itaparica Island, Bahia, Brazil

The antioxidant activity of Tetragonisca angustula honey (TAH) and its ethanolic extract (TAEE) were investigated. The total levels of phenolic (TPC) and flavonoids (TFC) were also evaluated. The results for TPC were 19.91 ± 0.38 and 29.37 ± 1.82 mg GAE g-1 and for TFC 0.20 ± 0.02 and 0.14 ± 0.01 mg QE g-1 of TAH and TAEE, respectively. Antioxidant activities were 73.29 ± 0.49% and 93.36 ± 0.27% in the DPPH● assay and 71.73 ± 4.07% and 97.86 ± 0.35% in ABTS●+ for TAH and TAEE, respectively. The total reducing activity was determined by the method of reducing power (PR) and iron ion (Fe III) and the results varied in PR from 151.7 ± 25.7 and 230.7 ± 25.2 mg GAE L-1, for TAH and TAEE respectively and for (Fe III) in EC50 0.284 in TAEE and 0.687 in TAH. Chemical analysis by HPLC-DAD of the ethanolic extract (TAEE) revealed the presence of ferulic acid as majority phenolic component in the extract. The 1H NMR analysis confirmed this structure and showed the also presence of glucose, citric acid, succinic acid, proline and hydrocarbon derivatives. In addition, the botanical origin was also investigated and showed a multifloral characteristic, having found 19 pollen types with a botanical predominance of the Anacardiaceae family, with Tapirira pollen occurring as predominant (42.6%) and Schinus as secondary (25.7%). The results showed that T. angustula honey is an interesting source of antioxidant phenolic compounds due to its floral origin and can act as a protector of human health when consumed.

Quality Assessment of Goldenrod, Milkweed and Multifloral Honeys Based on Botanical Origin, Antioxidant Capacity and Mineral Content

The goal of the study was to evaluate the pollen spectrum, antioxidant capacity and mineral content of four Hungarian honey types, using multivariate statistical analysis. The light colored honeys were represented by milkweed honey and a multifloral (MF) honey with dominant pollen frequency of linden (MF-Tilia); the darker ones were goldenrod honey and a multifloral honey with Lamiaceae pollen majority (MF-Lamiaceae). The pollen spectrum of the samples was established with melissopalynological analysis. The absorbance of the honeys positively correlated with the antioxidant capacity determined with three of the used methods (TRC, TEAC, DPPH), but not with ORAC. The latter method correlated negatively also with other antioxidant methods and with most of the mineral values. MF-Tilia had high ORAC value, K and Na content. The MF-Lamiaceae had the highest K, Mg, P, S, Cu and Zn content, the last five elements showing strict correlation with the TRC method. The darker goldenrod honey had higher SET values and total mineral content, than the milkweed honey. The above character-sets facilitate identification of each honey type and serve as indicators of variety. The antioxidant levels and mineral content of honeys allowed their clear separation by principal component analysis (PCA).

Honey moisture reduction using several thermal methods and their effects on its quality

Honey is thermally heated at various methods to decrease the moisture content and prolong the shelf life. The heating methods might decrease the quality of honey's physicochemical and biochemical properties. The present study thermally treated the honey with a pasteurizer, evaporator, and dehumidifier. The most thermally affected to decrease the moisture content were treatment by dehumidifier (14.09%), subsequent evaporation (8.41%), and pasteurization (8.41%). After heating, significant differentiation was also observed in the variation of both HMF (Hydroxymethylfurfural) content and diastase activity according to the botanical origin of the honey sample. In line with the biochemical analysis of honey, total phenolic decreased significantly during the pasteurization treatment. Evaporation was the most resistant thermal treatment due to its ability to maintain the level of HMF and the enzyme diastase as a standard for honey quality. However, changes made in physicochemical and biochemical quality are still in compliance with national and international legal limits.

Contribution of organic bee pollen to the determination of the botanical origin of honey and its impact on its biological properties

Background: Honey is a sweet and flavorful natural product which comes from a lot of nectar of medicinal plants. Objective: The aims of this study were to determine the botanical origin, physicochemical parameters and the antioxidant contents and antibacterial activities of some Algerian honeys. Method: The physico-chemical parameters of the honeys analyzed were measured using the methods established by the European Honey Commission. The antioxidant contents were determined using colorimetric assays, and the antioxidant activities were estimated using reducing power, DPPH, ABTS, and FRAP assays. Antibacterial activities were measured using sensitivity testing and minimal inhibitory concentration. Results: The majority of the samples analyzed were monofloral honeys (Fabaceae) and other medicinal plant pollens were shown (Asteraceae, Tiliaceae, Myrtaceae and Apiaceae). The physicochemical parameters of the honeys were in accordance with the legislation, and the analyses of proline and HMF confirmed their authenticity. The content of total phenolic compounds and total flavonoids ranged from 26 to 159 mg GAE/100 g and 10 to 43 mg EC/100 g, respectively. The analyzed honeys showed variable antioxidant activities that differed from one honey to another, and antibacterial activity tests showed that S. aureus and K. pneumoniae were the most sensitive strains with inhibition zones of 24 to 28 mm and 8 to 35 mm in diameter, respectively. Very high correlations were observed between color, antioxidants and antioxidant activities. Conclusion: This study confirmed the powerful properties of honey to trap free radicals and to inhibit bacterial growth that could be used as a therapeutic agent.

Greek Honey Authentication: Botanical Approach

Honey is a functional, honeybee product with a useful role in human nutrition and several health benefits. Greece is a Mediterranean region with several types of monofloral honey. Today, Greek honey has acquired an important position in national and international markets. Due to this increased industrialization and globalization, quality control is a necessity. Mislabeling constitutes one of the most notable types of fraudulence, while most consumers are looking for authentic honey. Moreover, producers and suppliers are searching for rapid and analytical methodologies to secure Greek honey in a competitive environment. In this context, we aimed to describe the classical (melissopalynological, physicochemical) and analytical (chromatographic, spectrometric, and spectroscopic) methods for the standardization of the botanical origin of Greek honey.

Botanical Origin Differentiation of Malaysian Stingless Bee Honey Produced by Heterotrigona itama and Geniotrigona thoracica Using Chemometrics

Stingless bee honey, specifically honeydew honey, is generally valued for its better health benefits than those of most blossom types. However, scientific studies about the differentiation of stingless bee honey based on honeydew and blossom origins are very limited. In this study, 13C NMR spectroscopy was employed to quantify the seven major sugar tautomers in stingless bee honey samples, and the major sugar compositions of both honeydew and blossom types were found not significantly different. However, several physicochemical properties of honeydew honey including moisture content, free acidity, electrical conductivity, ash content, acetic acid, diastase, hydrogen peroxide, and mineral elements levels were significantly higher; while total soluble solid, proline, and hydroxymethylfurfural were significantly lower than blossom honey. Greater antioxidant capacity in honeydew honey was proven with higher total phenolic compounds, ABTS, DPPH, superoxide radical scavenging activities, peroxyl radical inhibition, iron chelation, and ferric reducing power. Using principal component analysis (PCA), two clusters of stingless bee honey from the honeydew and blossom origin were observed. PCA also revealed that the differentiation between honeydew and blossom origin of stingless bee honey is possible with certain physicochemical and antioxidant parameters. The combination of NMR spectroscopy and chemometrics are suggested to be useful to determine the authenticity and botanical origin of stingless bee honey.

Physicochemical parameters and mineral components in Vietnam honey as a promising tool for classifying biological origin of honeys

Honey is known as a natural sweetener agent with high nutritional value and health benefits, especially premium honey because of its desirable flavour and medicinal properties. Because of this, honey has been a target of adulteration through the mixing of low-quality honey and mislabelling of the honey’s origin. The aim of this research considers the potential of using mineral and physicochemical data to authenticate the origin of honey. To this end, 40 samples of 8 botanica collected from 18 different regions of Vietnam were analysed for its metal contents (Na, K, Mg, Ca, Al, Cu, Fe, Mn, Zn, Pb, Cd, Ni, Cr, Co, As, Hg) and physicochemical parameters (pH and electrical conductivity). The data were processed by multivariate analysis, which allowed the classification of honey according to its botanical origin.

A New Approach for Determination of the Botanical Origin of Monofloral Bee Honey, Combining Mineral Content, Physicochemical Parameters, and Self-Organizing Maps

A new approach for the botanical origin determination of monofloral bee honey is developed. The methodology combines mineral content and physicochemical parameters determination with intelligent statistics such as self-organizing maps (SOMs). A total of 62 monofloral bee honey samples were analysed, including 31 linden, 14 rapeseed, 13 sunflower, and 4 acacia. All of them were harvested in 2018 and 2019 from trusted beekeepers, after confirming their botanical origin, using melissopalynological analysis. Nine physicochemical parameters were determined, including colour, water content, pH, electrical conductivity, hydroxymethylfurfural content, diastase activity, specific optical rotation, invertase activity, and proline. The content of thirty chemical elements (Ag, Al, As, B, Ba, Bi, Ca, Cd, Co, Cr, Cs, Cu, Fe, Ga, In, K, Li, Mg, Mn, Na, Ni, P, Pb, Rb, S, Se, Sr, Te, V, and Zn) was measured using ICP-OES, ICP-MS, and FAAS as instrumental techniques. The visualisation of the SOMs shows an excellent separation of honey samples in five well-defined clusters—linden, rapeseed, acacia, sunflower, and polyfloral honey—using the following set of 16 descriptors: diastase activity, hydroxymethylfurfural content, invertase activity, pH, specific optical rotation, water content, Al, B, Cr, Cs, K, Na, Ni, Rb, V, and Zn.