Quality and origin characterisation of Portuguese, Greek, Oceanian, and Asian honey, based on poly-parametric analysis hand in hand with dimension reduction and classification techniques

Conventional vs. Organically Produced Honey-Are There Differences in Physicochemical, Nutritional and Sensory Characteristics?

Honey is a sweet syrup mixture substance produced by honey bees. Contradictory results have been reported on the influence of organic and conventional beekeeping on the properties of honey. The aim of this research was to determine the potential difference between organically and conventionally produced honey of the same botanical origin (linden, acacia, chestnut, meadow). It was shown that the electrical conductivity (0.16-0.98 mS/cm), optical rotation (-1.00 - (-2.60) [α]D20), pH values (3.30-4.95), free acidity (4.0-9.0 mmol/kg), total content of phenolic (76.5-145.9 μg GAE/g dry weight (d.w.)) and flavonoids (48.7-307.0 μg QE/g d.w.), antioxidant potential, phenolic profile, mineral composition, color (-8.62-126.57 mmPfund) and sensory characteristics, although statistically significant differences were found, were not significantly improved better in the organic samples. All organic honey samples were richer in hydroxycinnamic acid derivatives (60.5-112.1 μg CGAE/g d.w.) compared to conventional honey (56.7-91.1 μg CGAE/g d.w.) of the corresponding botanical origin. The results show that organic beekeeping does not lead to the production of honey with significantly better physicochemical, nutritional and sensory properties compared to conventionally produced honey.

Further Insights on Honey and Propolis from Gerês (Portugal) and Their Bioactivities: Unraveling the Impact of Beehive Relocation

Propolis, a bee product, is known for its variability of chemical and bioactive profiles. However, Portuguese propolis from Gerês, normally obtained by mixing propolis from three places-Bugalho, Felgueiras and Toutelo-has shown similar chemical and biological profiles over the years. Recently, a new propolis place-Roca-was added to the apiary to replace Bugalho, lost to the 2017 wildfires, hence questioning the previously claimed constancy of Gerês propolis. To unravel to what extent the beehive relocation affected this constancy, we studied different Gerês propolis samples collected in three consecutive years (2017-2019) composed of different combinations of source places. Two honey samples, collected before (2017) and after (2018) the occurrence of the wildfire, were also investigated. Total phenolics, flavonoids and ortho-diphenols contents were determined and the antioxidant and antimicrobial activities were evaluated, using the DPPH assay and the agar dilution method, respectively. Although both antimicrobial and antioxidant activities were generally in the ranges usually obtained from Gerês propolis, some variations were detected for the samples, with different compositions when compared to previous years. This work reinforces the importance of the consistency of a combination of several factors for the protection and preservation of the flora near the hives, providing bee products with more constant chemical and biological profiles over the years.

Anti-bacterial, anti-biofilm and anti-quorum sensing activities of honey: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Man has used honey to treat diseases since ancient times, perhaps even before the history of medicine itself. Several civilizations have utilized natural honey as a functional and therapeutic food to ward off infections. Recently, researchers worldwide have been focusing on the antibacterial effects of natural honey against antibiotic-resistant bacteria.

AIM OF THE STUDY

This review aims to summarize research on the use of honey properties and constituents with their anti-bacterial, anti-biofilm, and anti-quorum sensing mechanisms of action. Further, honey's bacterial products, including probiotic organisms and antibacterial agents which are produced to curb the growth of other competitor microorganisms is addressed.

MATERIALS AND METHODS

In this review, we have provided a comprehensive overview of the antibacterial, anti-biofilm, and anti-quorum sensing activities of honey and their mechanisms of action. Furthermore, the review addressed the effects of antibacterial agents of honey from bacterial origin. Relevant information on the antibacterial activity of honey was obtained from scientific online databases such as Web of Science, Google Scholar, ScienceDirect, and PubMed.

RESULTS

Honey's antibacterial, anti-biofilm, and anti-quorum sensing activities are mostly attributed to four key components: hydrogen peroxide, methylglyoxal, bee defensin-1, and phenolic compounds. The performance of bacteria can be altered by honey components, which impact their cell cycle and cell morphology. To the best of our knowledge, this is the first review that specifically summarizes every phenolic compound identified in honey along with their potential antibacterial mechanisms of action. Furthermore, certain strains of beneficial lactic acid bacteria such as Bifidobacterium, Fructobacillus, and Lactobacillaceae, as well as Bacillus species can survive and even grow in honey, making it a potential delivery system for these agents.

CONCLUSION

Honey could be regarded as one of the best complementary and alternative medicines. The data presented in this review will enhance our knowledge of some of honey's therapeutic properties as well as its antibacterial activities.

Citrus Honeys from Three Different Regions of Turkey: HPLC-DAD Profiling and in Vitro Enzyme Inhibition, Antioxidant, Anti-Inflammatory and Antimicrobial Properties with Chemometric Study

The objectives of the present study are to compare the phenolic profiles and biological activities of 15 citrus honey samples from three different locations in Turkey using a chemometric approach. The HPLC-DAD analysis was used to determine phenolic profiles. Nineteen phenolic compounds were identified. Gallic acid (107.14-717.04 μg/g) was recorded as the predominant compound. AF (Antalya-Finike) had the highest antioxidant activity in ABTS⋅+ (IC50 : 18.01±0.69 mg/mL), metal chelating (IC50 : 6.20±0.19 mg/mL) and CUPRAC (A0.50 : 12.05±0.68 mg/mL) assays, while it revealed the best anti-inflammatory activity against COX-2 (17.28±0.22 %) and COX-1 (43.28±0.91 %). AM (Antalya-Manavgat) was the most active in β-carotene-linoleic acid (IC50 : 10.05±0.19 mg/mL), anti-urease (38.90±0.69 %), anti-quorum sensing and antimicrobial activities. AKO1 (Adana-Kozan-1) in DPPH⋅ (IC50 : 34.25±0.81 mg/mL) assay, AKU1 (Antalya-Kumluca-1) in tyrosinase inhibition activity (37.73±0.38 %) assay, AKU2 (Antalya-Kumluca-2) in AChE (10.55±0.63 %) and BChE (9.18±0.45 %) inhibition activity assays showed the best activity. Chemometric tools were applied to the phenolic compositions and biological properties. PCA and HCA ensured that 15 citrus honey samples were grouped into 3 clusters. The results showed that myricetin, kaempferol, vanillin, protocatechuic acid, rosmarinic acid, rutin, vanillic acid, gallic acid, catechin and p-hydroxyphenyl acetic acid are phenolic compounds that can be used in the classification of citrus honeys.

Potential Activity of Abrantes Pollen Extract: Biochemical and Cellular Model Studies

The aim of this study was to determine the grain composition and (poly)phenolic profile of pollen from Abrantes (Portugal), as well as its antioxidative and antidiabetic properties, and abilities to protect human erythrocytes against induced hemoglobin oxidation, lipid peroxidation, and hemolysis. The phytochemical profile of the Abrantes’ bee pollen revealed twenty phenolic compounds, identified by high-performance liquid chromatography with electrospray ionization mass spectrometry coupled with photodiode array detection. Among them, quercetin derivatives were the most abundant. Concerning the biological potential, the pollen extract showed notable capacity for 2,2-diphenyl-1-picrylhydrazyl, nitric oxide, and superoxide radicals, as well as for inhibition of α-glucosidase action, and protection of human erythrocytes against oxidative damage. Non-cytotoxic effects regarding the NHDF normal cell line, human adenocarcinoma Caco-2, and human liver HepG2 cells were observed. The results obtained contributed to further research on modes of action related to oxidative damage and metabolic health problems, to generate deeper knowledge of potential health-promoting effects to develop novel pharmaceutical drugs, nutraceuticals, and dietary supplements.

Phenolic Compounds in Honey and Their Relationship with Antioxidant Activity, Botanical Origin, and Color

Honey has been employed since antiquity due to its sensory, nutritional, and therapeutic properties. These characteristics are related to its physical and chemical composition. For example, phenolic compounds are substances that can determine antioxidant activity, as well as sensory characteristics, and can be employed as biomarkers of floral and geographical origin. This has generated a growing interest in the study of phenolic compounds and their influence in the intrinsic properties of this beekeeping product. This review aims to summarize, analyze, and update the status of the research that demonstrates the role of phenolic compounds in antioxidant activity, botanical-geographical origin, and the sensory characteristics of honey. These phenolic compounds, according to various results reported, have great relevance in honey's biological and functional activity. This leads to research that will link phenolic compounds to their floral, geographical, productive, and territorial origin, as well as some sensory and functional characteristics.

Quality, composition and health-protective properties of citrus honey: A review

Citrus honey is one of the most important monofloral honeys produced and consumed worldwide. This honey has pleasant sensorial characteristics, which include light color and typical aroma and flavor. Besides that, several constituents such as minerals, phenolic and volatile compounds, amino acids, sugars, enzymes, vitamins, methylglyoxal and organic acids are found in citrus honey. Moreover, potential biological properties have been associated with citrus honey. All these factors make it highly desired by consumers, increasing its market value, which can stimulates the practice of fraud. Also, citrus honey is susceptible to contamination and to inadequate processing. All these factors can compromise the quality, safety and authenticity of citrus honey. In this sense, this review aims to update and to discuss, for the first time, the data available in the literature about the physicochemical and the sensorial characteristics, composition, health properties, contamination, authenticity and adulteration of citrus honey. With this background, we aim to provide data that can guide future researches related to this honey.

Pollen diversity in honeys of the Czech Republic in the 2019 season

Honeybees are important pollinators. As a side product of pollination, honeybees produce honey, as a natural sweetener. The source of honey depends on the hive location. In specific conditions honeybees produce monofloral honey, but more common are polyfloral kinds of honey. In this study honey from the Czech Republic in the 2019 season was evaluated by melissopalynology analysis. The common botanical taxa in the Czech Republic were determined and season impact to pollen taxa was compared for dominant pollen taxa. The taxonomic distribution of pollen in Czech honey was stable during the year. The average number of species was 11.52 taxa per sample. The dominant pollen source in Czech honey was the Brassicaceae family. The high pollen content in honey was confirmed also in the Rosacea family (fruit tree), Ubelliferacae family and Myosotis genus. During the year the pollen taxa were equally distributed in honey. Seasonal effects were confirmed only in Salix genus, Ubelliferacae family and Phacelia genus. Seasonal effects correspond with the blooming season and honeybee handling in the hive was also confirmed. High variability during the season and hive location was confirmed for other taxa.

Honey: Another Alternative in the Fight against Antibiotic-Resistant Bacteria?

Antibacterial resistance has become a challenging situation worldwide. The increasing emergence of multidrug-resistant pathogens stresses the need for developing alternative or complementary antimicrobial strategies, which has led the scientific community to study substances, formulas or active ingredients used before the antibiotic era. Honey has been traditionally used not only as a food, but also with therapeutic purposes, especially for the topical treatment of chronic-infected wounds. The intrinsic characteristics and the complex composition of honey, in which different substances with antimicrobial properties are included, make it an antimicrobial agent with multiple and different target sites in the fight against bacteria. This, together with the difficulty to develop honey-resistance, indicates that it could become an effective alternative in the treatment of antibiotic-resistant bacteria, against which honey has already shown to be effective. Despite all of these assets, honey possesses some limitations, and has to fulfill a number of requirements in order to be used for medical purposes.