Search

This study reports on the physicochemical and sensory attributes, total phenolic content, and antioxidant activity of 36 honey samples produced by two different stingless bee species (Tetragonula carbonaria and Tetragonula hockingsi) from Australia. The findings reveal moisture content across all samples ranges from 24.9% to 30.8% (w/w), electrical conductivity from 1.02 to 2.15 mS/cm, pH levels between 3.57 and 6.54, soluble solids from 69.2 to 75.1 °Brix, trehalulose concentrations from 6.20 to 38.2 g/100 g, fructose levels from 7.79 to 33.4 g/100 g, and glucose content from 3.36 to 26.8 g/100 g. Sucrose was undetectable in all investigated samples. In a sensory analysis involving 30 participants, Australian stingless bee honey was perceived as having a more pronounced sourness compared with New Zealand Manuka honey. The study reveals considerable variability in the composition of Australian stingless bee honey, influenced by factors such as floral availability, geographical origin, and time of harvest. It also demonstrates the presence of phenolic compounds and antioxidant activity in stingless bee honey, underlining their potential as a natural source of antioxidants. All investigated samples contain trehalulose, which supports the findings of other recent studies that propose this unusual disaccharide as a marker compound of stingless bee honey. [ABSTRACT FROM AUTHOR]

The genus Leptospermum (Myrtaceae) is widespread in Australia and contains several species that are of increasing interest to produce bioactive honey. Here, we used the Maxent algorithm to investigate bioclimatic, climatic, and soil variables as predictors for potential distributions of seven Leptospermum species that have been identified as useful for bioactive honey production in Australia (L. lanigerum, L. liversidgei, L. nitens, L. polygalifolium, L. scoparium, L. speciosum, and L. whitei). Bioclimatic and climatic variables, mainly those related to moist conditions, were the best predictors for the distribution of the species. Leptospermum lanigerum and L. scoparium were suitable species in areas in southwestern Australia and Tasmania, while L. polygalifolium was suitable for eastern Australia. For L. nitens, appropriate areas were found only in western and southern regions, whereas only border ranges in Queensland and New South Wales were considered suitable for L. liversidgei, L. speciosum, and L. whitei. Notably, the latter areas were identified as a potential 'hotspot' for Leptospermum species. Our study can assist the incipient Leptospermum honey industry in Australia in identifying suitable local species and the local maintenance requirements for the species chosen. [ABSTRACT FROM AUTHOR]

The propolis industry is well established in European, South American and East Asian countries. Within Australia, this industry is beginning to emerge with a few small-scale producers. To contribute to the development of the Australian propolis industry, the present study aimed to examine the quality and chemical diversity of propolis collected from various regions across Australia. The results of testing 158 samples indicated that Australian propolis had pure resin yielding from 2 to 81% by weight, total phenolic content and total flavonoid content in one gram of dry extract ranging from a few up to 181 mg of gallic acid equivalent and 145 mg of quercetin equivalent, respectively. Some Australian propolis showed more potent antioxidant activity than the well-known Brazilian green, Brazilian red, and Uruguayan and New Zealand poplar-type propolis in an in vitro DPPH assay. In addition, an HPLC–UV analysis resulted in the identification of 16 Australian propolis types which can be considered as high-grade propolis owing to their high total phenolic content. Chemometric analysis of their 1H NMR spectra revealed that propolis originating from the eastern and western coasts of Australia could be significantly discriminated based on their chemical composition. [ABSTRACT FROM AUTHOR]

Variation in the antibacterial potency of manuka honey has been reported in several published studies. However, many of these studies examine only a few honey samples, or test activity against only a few bacterial isolates. To address this deficit, a collection of 29 manuka/Leptospermum honeys was obtained, comprising commercial manuka honeys from Australia and New Zealand and several Western Australian Leptospermum honeys obtained directly from beekeepers. The antibacterial activity of honeys was quantified using several methods, including the broth microdilution method to determine minimum inhibitory concentrations (MICs) against four species of test bacteria, the phenol equivalence method, determination of antibacterial activity values from optical density, and time kill assays. Several physicochemical parameters or components were also quantified, including methylglyoxal (MGO), dihydroxyacetone (DHA), hydroxymethylfurfural (HMF) and total phenolics content as well as pH, colour and refractive index. Total antioxidant activity was also determined using the DPPH* (2,2-diphenyl-1-picrylhydrazyl) and FRAP (ferric reducing–antioxidant power) assays. Levels of MGO quantified in each honey were compared to the levels stated on the product labels, which revealed mostly minor differences. Antibacterial activity studies showed that MICs varied between different honey samples and between bacterial species. Correlation of the MGO content of honey with antibacterial activity showed differing relationships for each test organism, with Pseudomonas aeruginosa showing no relationship, Staphylococcus aureus showing a moderate relationship and both Enterococcus faecalis and Escherichia coli showing strong positive correlations. The association between MGO content and antibacterial activity was further investigated by adding known concentrations of MGO to a multifloral honey and quantifying activity, and by also conducting checkerboard assays. These investigations showed that interactions were largely additive in nature, and that synergistic interactions between MGO and the honey matrix did not occur. [ABSTRACT FROM AUTHOR]

Honey is a popular agricultural product containing mostly sugars and water, but due to its nutritious components and natural production by honeybees (Apis mellifera) from floral nectar, it is marketed as a premium health food item. As environmental monitors, honeybees can potentially transfer environmental contaminants to honey. Whilst pesticides can have ubiquitous presence in agricultural and urban areas, polycyclic aromatic hydrocarbons (PAHs) can be more prevalent in higher density urban/industrial environments. Australian beehives are customarily located in rural areas/forests, but it is increasingly popular to keep hives in urban areas. This study assessed the levels of environmental contaminants in honeys (n = 212) from Queensland/Australian sources including rural, peri-urban and urban areas. Honey samples were analysed by LC-MS/MS and GC-MS/MS for 53 herbicides, 83 pesticides, 18 breakdown products (for certain pesticides/herbicides) and 33 PAHs and showed low/negligible pesticide, herbicide and PAHs contamination, consistent regardless of honey origins. [ABSTRACT FROM AUTHOR]

Accurate identification of the botanical components of honey can be used to establish its geographical provenance, while also providing insights into honeybee (Apis mellifera L.) diet and foraging preferences. DNA metabarcoding has been demonstrated as a robust method to identify plant species from pollen and pollen‐based products, including honey. We investigated the use of pollen metabarcoding to identify the floral sources and local foraging preferences of honeybees using 15 honey samples from six bioregions from eastern and western Australia. We used two plant metabarcoding markers, ITS2 and the trnL P6 loop. Both markers combined identified a total of 55 plant families, 67 genera, and 43 species. The trnL P6 loop marker provided significantly higher detection of taxa, detecting an average of 15.6 taxa per sample, compared to 4.6 with ITS2. Most honeys were dominated by Eucalyptus and other Myrtaceae species, with a few honeys dominated by Macadamia (Proteaceae) and Fabaceae. Metabarcoding detected the nominal primary source provided by beekeepers among the top five most abundant taxa for 85% of samples. We found that eastern and western honeys could be clearly differentiated by their floral composition, and clustered into bioregions with the trnL marker. Comparison with previous results obtained from melissopalynology shows that metabarcoding can detect similar numbers of plant families and genera, but provides significantly higher resolution at species level. Our results show that pollen DNA metabarcoding is a powerful and robust method for detecting honey provenance and examining the diet of honeybees. This is particularly relevant for hives foraging on the unique and diverse flora of the Australian continent, with the potential to be used as a novel monitoring tool for honeybee floral resources. [ABSTRACT FROM AUTHOR]

Background: When aiming to develop dietary messaging to achieve reductions in added sugar intakes, it is necessary to identify key food contributors. Food contributors are not expected to remain static over time. Therefore, the present study aimed to compare the total added sugars (AS) intake and related food sources for adult respondents of two Australian national consumption surveys. Methods: Repeated 24‐h recall data from the 1995 National Nutrition Survey (1995NNS, n = 10 851) and the 2011–12 National Nutrition and Physical Activity Survey (2012NNPAS, n = 9341) was used to estimate AS consumption. Food group sources of AS were examined per consumer and per capita and the food group predictors of energy provided by AS were determined. Results: A significant difference in total AS intake was identified by age and gender between the surveys (all P < 0.001). Increased variability in food group contributions per consumer was also identified. Nine of the top 20 food groups from the 1995NNS differed (P < 0.001) in their contribution to AS in 2012NNPAS per consumer. Fewer changes were apparent at the population level, with >40% AS coming from only three food groups. Age‐stratified analyses showed that the 'sugar, honeys and syrups' and the 'sweetened beverages' food groups were the top contributors between the surveys up to the age group of 70 years. 'Sugar, honey and syrups', 'chocolate and chocolate‐based confectionery,' and 'other confectionery' (all, P < 0.001) were significant predictors of AS intake (1995NNS, r2 = 0.755; 2012NNPAS r2 = 0.740). Conclusions: At a population level, food group contributions to AS intakes for Australian adults have not changed substantially over time, yet notable shifts in AS can be seen when targeting only the consumers of these food sources. 'Cake type desserts' appear to be increasingly consumed though 'sweetened beverages' remain a major contributor to AS intakes warranting targeted public health strategies. [ABSTRACT FROM AUTHOR]

The phenol equivalence assay is the current industry-adopted test used to quantify the antibacterial activity of honeys in Australia and New Zealand. Activity is measured based on the diffusion of honey through agar and resulting zone of growth inhibition. Due to differences in the aqueous solubilities of antibacterial compounds found in honeys, this method may not be optimal for quantifying activity. Therefore, a new method was developed based on the existing broth microdilution assay that is widely used for determining minimum inhibitory concentrations (MICs). It utilises the four organisms Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853, and an optical density endpoint to quantify bacterial growth. Decreases in bacterial growth in the presence of honey, relative to the positive growth control, are then used to derive a single value to represent the overall antibacterial activity of each honey. Antibacterial activity was quantified for a total of 77 honeys using the new method, the phenol equivalence assay and the standard broth microdilution assay. This included 69 honeys with undisclosed floral sources and the comparators Manuka, Jarrah (Eucalyptus marginata), Marri (Corymbia calophylla), artificial and multifloral honey. For the 69 honey samples, phenol equivalence values ranged from 0–48.5 with a mean of 34 (% w/v phenol). Mean MICs, determined as the average of the MICs obtained for each of the four organisms for each honey ranged from 7–24% (w/v honey). Using the new assay, values for the 69 honeys ranged from 368 to 669 activity units, with a mean of 596. These new antibacterial activity values correlated closely with mean MICs (R2 = 0.949) whereas the relationship with phenol equivalence values was weaker (R2 = 0.649). Limit of detection, limit of quantitation, measuring interval, limit of reporting, sensitivity, selectivity, repeatability, reproducibility, and ruggedness were also investigated and showed that the new assay was both robust and reproducible. [ABSTRACT FROM AUTHOR]

Stingless bee honeys (SBHs) from Australian and Malaysian species were analysed using ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) for the presence of pyrrolizidine alkaloids (PAs) and the corresponding N -oxides (PANOs) due to the potential for such hepatotoxic alkaloids to contaminate honey as a result of bees foraging on plants containing these alkaloids. Low levels of alkaloids were found in these SBHs when assessed against certified PA standards in targeted analysis. However, certain isomers were identified using untargeted analysis in a subset of honeys of Heterotrigona itama which resulted in the identification of a PA weed species ( Ageratum conyzoides ) near the hives. The evaluation of this weed provided a PA profile matching that of the SBH of H. itama produced nearby, and included supinine, supinine N -oxide (or isomers) and acetylated derivatives. These PAs lacking a hydroxyl group at C7 are thought to be less hepatoxic. However, high levels were also observed in SBH (and in A. conyzoides ) of a potentially more toxic diester PA corresponding to an echimidine isomer. Intermedine, the C7 hydroxy equivalent of supinine, was also observed. Species differences in nectar collection were evident as the same alkaloids were not identified in SBH of G. thoracica from the same location. This study highlights that not all PAs and PANOs are identified using available standards in targeted analyses and confirms the need for producers of all types of honey to be aware of nearby potential PA sources, particularly weeds.

Mānuka honey is a valuable commodity produced by bees foraging the flowers of Leptospermum scoparium , a bush native to New Zealand and Australia. Due to its high value and proven health benefits, authenticity fraud in the sale of this food is a significant risk, as recounted in the literature. Four compulsory natural products must be present at minimum concentrations to authenticate mānuka honey (3-phenyllactic acid, 2′-methoxyacetophenone, 2-methoxybenzoic acid, and 4-hydroxyphenyllactic acid). However, spiking other kinds of honey with these compounds and/or the dilution of mānuka honey with other varieties may result in fraud going undetected. In this work, liquid chromatography coupled with high-resolution mass spectrometry and a metabolomics-based strategy has allowed us to tentatively identify 19 natural products –putative mānuka honey markers–, nine of which are reported for the first time. Chemometric models applied to these markers allowed the detection of both spiking and dilution fraud attempts of mānuka honey, even at 75% mānuka honey purity. Thus, the herein-reported methodology can be employed in the prevention and detection of mānuka honey adulteration even at low levels, and the tentatively identified markers presented in this work proved valuable for mānuka honey authentication procedures. [Display omitted] • Mānuka honey is a valuable commodity for which fraud has been reported. • Fraud via spiking of natural products or via dilution with other honeys is possible. • Employing HRMS, 19 natural products in mānuka honey have been identified. • 12 of them are mānuka exclusive, of which nine had never been reported in mānuka. • Statistical analysis permitted authenticating mānuka honey against fraud attempts. [ABSTRACT FROM AUTHOR]

Honey produced by the Australian honeypot ant ( Camponotus inflatus ) is valued nutritionally and medicinally by Indigenous peoples, but its antimicrobial activity has never been formally studied. Here, we determine the activity of honeypot ant honey (HPAH) against a panel of bacterial and fungal pathogens, investigate its chemical properties, and profile the bacterial and fungal microbiome of the honeypot ant for the first time. We found HPAH to have strong total activity against Staphylococcus aureus but not against other bacteria, and strong non-peroxide activity against Cryptococcus and Aspergillus sp. When compared with therapeutic-grade jarrah and manuka honey produced by honey bees, we found HPAH to have a markedly different antimicrobial activity and chemical properties, suggesting HPAH has a unique mode of antimicrobial action. We found the bacterial microbiome of honeypot ants to be dominated by the known endosymbiont genus Candidatus Blochmannia (99.75%), and the fungal microbiome to be dominated by the plant-associated genus Neocelosporium (92.77%). This study demonstrates that HPAH has unique antimicrobial characteristics that validate its therapeutic use by Indigenous peoples and may provide a lead for the discovery of novel antimicrobial compounds., Competing Interests: Dee A. Carter is an Academic Editor for PeerJ., (© 2023 Dong et al.)

Most commercially available therapeutic honey is derived from flowering Leptospermum scoparium (manuka) plants from New Zealand. Australia has more than 80 Leptospermum species, and limited research to date has found at least some produce honey with high non-peroxide antibacterial activity (NPA) similar to New Zealand manuka, suggesting Australia may have a ready supply of medical-grade honey. The activity of manuka honey is largely due to the presence of methylglyoxal (MGO), which is produced non-enzymatically from dihydroxyacetone (DHA) present in manuka nectar. The aims of the current study were to chemically quantify the compounds contributing to antibacterial activity in a collection of Australian Leptospermum honeys, to assess the relationship between MGO and NPA in these samples, and to determine whether NPA changes during honey storage. Eighty different Leptospermum honey samples were analysed, and therapeutically useful NPA was seen in samples derived from species including L. liversidgei and L. polygalifolium. Exceptionally high levels of up to 1100 mg/kg MGO were present in L. polygalifolium honey samples sourced from the Northern Rivers region in NSW and Byfield, QLD, with considerable diversity among samples. There was a strong positive relationship between NPA and MGO concentration, and DHA was present in all of the active honey samples, indicating a potential for ongoing conversion to MGO. NPA was stable, with most samples showing little change following seven years of storage in the dark at 4°C. This study demonstrates the potential for Australian Leptospermum honey as a wound care product, and argues for an extension of this analysis to other Leptospermum species. [ABSTRACT FROM AUTHOR]

Honey stimulates cellular secretion of cytokines, which has been attributed to activation of lipopolysaccharide (LPS)-dependent and LPS-independent pathways. The objective of this study was to identify whether LPS is present in Australian honey samples at levels that can stimulate interleukin-6 (IL-6) secretion by fibroblasts and whether it can transduce cell signalling by activating toll-like receptor 4 (TLR4). IL-6 was measured in culture media of fibroblasts exposed to honey for 24 h. LPS was detected in a 0.125 mg/mL solution of grey ironbark honey (0.61 ± 0.05 ng/g honey). TLR4 signalling was observed in RAW264.7 macrophages that were exposed to honey and this was prevented by preincubating the honey with the LPS-neutralising agent, polymyxin B. Australian Eucalyptus, Leptospermum and Cyathode honeys stimulated IL-6 secretion in cultured human dermal fibroblasts. To examine whether the response was dependent on floral source, fibroblasts were exposed to four different samples of grey ironbark honey obtained from Queensland and New South Wales, Australia. The magnitude of the cytokine response to these honeys was highly varied. We conclude that Australian honeys contain endotoxin at levels that can stimulate IL-6 secretion by fibroblasts and that signalling in macrophages involves TLR4 activation. The IL-6 secretory response was independent of floral source., (© 2022. The Author(s).)

• All stingless bee honeys (SBH) failed CODEX honey standard but partially met MS2683. • Trehalulose was the main sugar in all SBH and notably higher in G. thoracica honey. • Malaysian and Australian SBH have distinctly different physicochemical properties. Stingless bee honey (SBH) of four stingless bee species (Heterotrigona itama, Geniotrigona thoracica, Tetragonula carbonaria , and Tetragonula hockingsi) from two geographic regions (Malaysia and Australia, n = 36) were studied for their physicochemical parameters, including total phenolic and multi-elemental contents. Sugar analysis confirmed the prominent presence of trehalulose in all samples. All SBH failed to meet the CODEX Standard for honey moisture, free acidity, and total fructose plus glucose levels. One-way ANOVA, principal component analysis (PCA) and hierarchical component analysis (HCA) confirm distinctive differences between Australian and Malaysian SBH with Australian SBH having significantly (P < 0.05) higher pH, total phenolic, total mineral, and electrical conductivity attributes. Toxic elements in all SBH were much lower than standard CODEX limit. The species G. thoracica produced honey with significantly (P < 0.05) higher trehalulose than both Australian bee species. This research will add value to SBH and hasten new international standards ensuring commercial viability, safety, quality, and marketability of SBH. [ABSTRACT FROM AUTHOR]

Chronic wound infections and antibiotic resistance are driving interest in antimicrobial treatments that have generally been considered complementary, including antimicrobially active honey. Australia has unique native flora and produces honey with a wide range of different physicochemical properties. In this study we surveyed 477 honey samples, derived from native and exotic plants from various regions of Australia, for their antibacterial activity using an established screening protocol. A level of activity considered potentially therapeutically useful was found in 274 (57%) of the honey samples, with exceptional activity seen in samples derived from marri (Corymbia calophylla), jarrah (Eucalyptus marginata) and jellybush (Leptospermum polygalifolium). In most cases the antibacterial activity was attributable to hydrogen peroxide produced by the bee-derived enzyme glucose oxidase. Non-hydrogen peroxide activity was detected in 80 (16.8%) samples, and was most consistently seen in honey produced from Leptospermum spp. Testing over time found the hydrogen peroxidedependent activity in honey decreased, in some cases by 100%, and this activity was more stable at 4°C than at 25°C. In contrast, the non-hydrogen peroxide activity of Leptospermum honey samples increased, and this was greatest in samples stored at 25°C. The stability of non-peroxide activity from other honeys was more variable, suggesting this activity may have a different cause. We conclude that many Australian honeys have clinical potential, and that further studies into the composition and stability of their active constituents are warranted. [ABSTRACT FROM AUTHOR]

Arthropod-borne viruses (arboviruses) represent a global public health problem, with dengue viruses causing millions of infections annually, while emerging arboviruses, such as West Nile, Japanese encephalitis, and chikungunya viruses have dramatically expanded their geographical ranges. Surveillance of arboviruses provides vital data regarding their prevalence and distribution that may be utilized for biosecurity measures and the implementation of disease control strategies. However, current surveillance methods that involve detection of virus in mosquito populations or sero-conversion in vertebrate hosts are laborious, expensive, and logistically problematic. We report a unique arbovirus surveillance system to detect arboviruses that exploits the process whereby mosquitoes expectorate virus in their saliva during sugar feeding. In this system, infected mosquitoes captured by CO2-baited updraft box traps are allowed to feed on honey-soaked nucleic acid preservation cards within the trap. The cards are then analyzed for expectorated virus using real-time reverse transcription-PCR. In field trials, this system detected the presence of Ross River and Barmah Forest viruses in multiple traps deployed at two locations in Australia. Viral RNA was preserved for at least seven days on the cards, allowing for long-term placement of traps and continuous collection of data documenting virus presence in mosquito populations. Furthermore no mosquito handling or processing was required and cards were conveniently shipped to the laboratory overnight. The simplicity and efficacy of this approach has the potential to transform current approaches to vector-borne disease surveillance by streamlining the monitoring of pathogens in vector populations. [ABSTRACT FROM AUTHOR]

Previous research on remote nineteenth-and early twentieth-century Indigenous missions in northern and central Australia point to their often tenuous existence and the complex nature of engagements between Christian Missionaries and Indigenous people. This paper explores the contribution and significance of Indigenous production of wild foods in the context of one such settlement located at Weipa on Cape York Peninsula, north eastern Australia. It is premised on the assertion that investigation of the economies of these often remote settlements has the potential to reveal much about the character of cross-cultural engagements within the context of early mission settlements. Many remote missions had a far from secure economic basis and were sometimes unable to produce the consistent food supplies that were central to their proselytizing efforts. In this paper it is suggested that Indigenous-produced wild foods were of significant importance to the mission on a day-to-day basis in terms of their dietary contribution (particularly in terms of protein sources) and were also important to Indigenous people from a social and cultural perspective. We develop this argument through the case study of culturally modified trees that resulted from the collection of wild honey. [ABSTRACT FROM AUTHOR]

While the ancient Egyptians and Greeks used honey for wound care, and a broad spectrum of wounds are treated all over the world with natural unprocessed honeys from different sources, Medihoney™ has been one of the first medically certified honeys licensed as a medical product for professional wound care in Europe and Australia. Our experience with medical honey in wound care refers only to this product. In this review, we put our clinical experience into a broader perspective to comment on the use of medical honey in wound care. More prospective randomized studies on a wider range of types of wounds are needed to confirm the safety and efficacy of medical honey in wound care. Nonetheless, the current evidence confirming the antibacterial properties and additional beneficial effects of medical honey on wound healing should encourage other wound care professionals to use CE-certified honey dressings with standardized antibacterial activity, such as Medihoney™products, as an alternative treatment approach in wounds of different natures. [ABSTRACT FROM AUTHOR]

Polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP) analysis and microscopy were used to test 307 adult bee and 37 honey samples collected in Australia for the presence of two microsporidia, Nosema ceranae and Nosema apis. N. ceranae was detected in samples from 4 states (Queensland, New South Wales, Victoria and South Australia) and was most commonly found in samples from Queensland where 28 (33.7%) of 83 samples were positive. New South Wales had the second highest prevalence with 15 (15.8%) of 95 samples positive. South Australia and Victoria had 4 (16%) of 25 and 2 (4.5%) of 44 samples positive respectively. N. ceranae was not detected in samples from Western Australia and Tasmania. N. apis was detected in samples from all states. Three honey samples (8.1%) were PCR positive for N. ceranae. These positive honey samples originated from beekeepers in Queensland. Six imported honey samples tested were negative for both Nosema spp. [ABSTRACT FROM AUTHOR]

• Rapid chemical profiling of Manuka honey with ambient mass spectrometry and chemometric modelling. • Real-time authentication of Manuka honey by production batch. • Chemometric differentiation of Manuka honey by production batch, brand, and adulteration scenarios. • Honey authentication and fraud detection of Manuka honey for brand protection. Manuka honey is a high-value and commonly adulterated food commodity that is produced by Apis mellifera bees from the nectar of the bush Leptospermum scoparium found exclusively in New Zealand and some parts of Australia. In this study, a rapid method using a compact atmospheric solid analysis probe (ASAP) mass spectrometer (MS) and chemometric modelling was used for the authentication of Manuka honey. Class separation was observed for Manuka honey of different production batches, brands, and grades, whereas no class separation was observed for Manuka honey of the same production batch. A one-class model training set of a production batch of honey was built (R2 = 0.845; Q2 = 0.686). Model validation with a prediction set of Manuka honey consisting of samples of the same production batch not used in the model, different production batches, brands, and grades gave and a perfect classifier (AUC = 1) for the receiver operator characteristic (ROC) indicating 100 % correct classification of class samples and outliers. Additionally, validation of the model against adulterated Manuka honey gave an AUC = 0.96 for the ROC. The results in this study indicate that compositional differences between production batches of Manuka honey could be used as unique chemical fingerprints for Manuka honey authentication for the purpose of brand protection and fraud detection. [ABSTRACT FROM AUTHOR]

Seven phenolic acids related to the botanical origins of nine monofloral Eucalyptus honeys from Australia, along with two abscisic isomers, have been analyzed. The mean content of total phenolic acids ranges from 2.14 mg/100 g honey of black box (Eucalyptus largiflorens) honey to 10.3 mg/100 g honey of bloodwood (Eucalyptus intermedia) honey, confirming an early finding that species-specific differences of phytochemical compositions occur quantitatively among these Eucalyptus honeys. A common profile of phenolic acids, comprising gallic, chlorogenic, coumaric and caffeic acids, can be found in all the Eucalyptus honeys, which could be floral markers for Australian Eucalyptus honeys. Thus, the analysis of phenolic acids could also be used as an objective method for the authentication of botanical origin of Eucalyptus honeys. Moreover, all the honey samples analyzed in this study contain gallic acid as the main phenolic acid, except for stringybox (Eucalyptus globoidia) honey which has ellagic acid as the main phenolic acid. This result indicates that the species-specific differences can also be found in the honey profiles of phenolic acids. Furthermore, the analysis of abscisic acid in honey shows that the content of abscisic acid varies from 0.55 mg/100 g honey of black box honey to 4.68 mg/100 g honey of bloodwood honey, corresponding to the contents of phenolic acids measured in these honeys. These results have further revealed that the HPLC analysis of honey phytochemical constituents could be used individually and/or jointly for the authentication of the botanical origins of Australian Eucalyptus honeys. [Copyright &y& Elsevier]

Flavonoids in Australian honeys from five botanical species (Melaleuca, Guioa, Lophostemon, Banksia and Helianthus) have been analyzed in relation to their floral origins. Tea tree (Melaleuca quinquenervia) and heath (Banksia ericifolia) honeys show a common flavonoid profile comprising myricetin (3,5,7,3′,4′,5′-hexahydroxyflavone), tricetin (5,7,3′,4′,5′-pentahydroxyflavone), quercetin (3,5,7,3′,4′-pentahydroxyflavone) and luteolin (5,7,3′,4′-tetrahydroxyflavone), which was previously suggested as a floral marker for an Australian Eucalyptus honey (bloodwood or Eucalyptus intermedia honey). These honeys of various floral species can be differentiated by their levels of total flavonoids, being 2.12 mg/100 g for heath honey and 6.35 m/100 g for tea tree honey. In brush box (Lophostemon conferta) honey, the flavonoid profile comprising mainly tricetin, luteolin and quercetin is similar to that of another Eucalyptus honey (yellow box or Eucalyptus melliodora honey). These results indicate that the flavonoid profiles in some of the Australian non-Eucalyptus honeys may contain more or less certain flavonoids from Eucalyptus floral sources because of the diversity and extensive availability of Eucalyptus nectars for honeybee foraging yearly around or a possible cross contamination of the monofloral honeys during collection, transportation and/or storage. Further analyses are required to differentiate and/or verify the botanical sources of the flavonoids that contribute to the flavonoid profiles of these honeys, by restricting honey sampling areas and procedures, employing other complementary analytical methods (e.g. pollen analysis, sugar profile) and using materials (e.g. nectar) directly sourced from the flowering plant for comparative studies. In Australian crow ash (Guioa semiglauca) honey, myricetin, tricetin, quercetin, luteolin and an unknown flavonoid have been found to be the main flavonoids, which is characteristic only to this type of honey, and could thus be used as the floral marker, while in Australian sunflower (Helianthus annuus) honey, the content of total flavonoids is the smallest amount comparing to those in the other honeys analysed in this study. However, the flavonoid quercetin and the flavonoid profile mainly consisting of quercetin, quercetin 3,3′-dimethyl ether (5,7,4′-trihydroxy-3,3′-dimethoxyflavone), myricetin and luteolin are characteristic only to this sunflower honey and could thus be used for the authentication. [Copyright &y& Elsevier]

Rheological properties of four unprocessed unifloral Australian honeys (heath, tea tree, yapunya, and yellow box) and an artificial honey were analysed at 20°C. A model previously used to describe viscosity data of various sugar and sugar mixtures was used to describe the concentration dependence of the viscosity of honey samples with varying moisture contents. The model successfully described the sugar concentration dependence of the unadulterated and medium moisture (70–85% solids) range honey samples. [ABSTRACT FROM AUTHOR]

Manuka honey (MH) is a mono-floral honey obtained from the Manuka tree (Leptospermum scoparium) belonging to the Myrtaceae family and grows as a shrub or a small tree mostly throughout New Zealand and Eastern Australia. MH is highly valued for its non-peroxide antibacterial properties mainly attributed to its exclusive content of methylglyoxal (MGO). Additionally, MH is rich in macro-and micro-nutrients including, sugars, free amino acids, proteins, enzymes, essential minerals, vitamins, and various secondary metabolites (flavonoids, phenolic acids, and 1, 2-dicarbonyl compounds). The presence of these beneficial phytochemicals is directly linked to its favored health benefits viz. , wound healing, anticancer, antioxidant, and anti-inflammatory effects. Significant modern pharmacological and clinical evidence have highlighted the wide medicinal applications of MH as a unique mono-floral honey. This comprehensive review capitalizes on MH with emphasis on the interrelationship between its holistic chemical composition, metabolism, action mechanisms, and health effects. Moreover, the review recapitulates the diverse health benefits of MH and related patents in food and functional food applications. MH health benefits are credited to its unique chemical composition. It represents an alternative remedy for different ailments to include bacterial, fungal, parasitic, and viral infections, and is currently exploited in a massive number of patents. Nevertheless, further studies are needed to uncover its action mechanism in wound healing, how to improve its pharmacokinetics, and to identify its bio-transformed metabolites inside the body. [ABSTRACT FROM AUTHOR]

Objectives: Oral mucositis is a debilitating oncology treatment side effect, with honey identified as a viable management option due to established wound-healing abilities. However, effects of saliva on properties attributed to honey's wound-healing abilities is unknown. Therefore, this study aimed to identify interactions between saliva, and antioxidant characteristics and pH of honey., Methods: Saliva was collected from 15 healthy participants (Females n=9; mean age=34.1 ± 11.2 years). Centrifuged salivary supernatant, whole saliva, and water were independently used to dilute commercial Australian honeys (n=42). Antioxidant characteristics (DPPH and FRAP) and pH of diluted honeys were analysed, and differences between dilution conditions were determined., Results: Honey and saliva dilutions increased antioxidant characteristics compared to water, and addition of honey to saliva reduced pH compared with saliva alone. There were significant differences between dilutions for FRAP and pH, and water and salivary conditions for DPPH (p<0.001). No difference was observed between salivary conditions for DPPH (p=0.931), suggesting smaller cells remaining in the supernatant possess antioxidant abilities. However, differences observed for FRAP suggest precipitable molecules, including epithelial and food debris, could provide additional antioxidant power., Conclusions: The addition of saliva to honey may support properties attributed to honey's wound-healing abilities and should be considered in the context of oral mucositis management., (© 2021 Walter de Gruyter GmbH, Berlin/Boston.)

The beneficial disaccharide, trehalulose, is a feature of stingless bee honey, while not dominant in any other foods. By experimentally feeding sugar solutions to confined colonies of the Australian stingless bee Tetragonula carbonaria , the origin of trehalulose has now been established. Complete conversion of fed sucrose was observed, by analysis of the honey, forming trehalulose (64-72%) with lesser erlose (18-23%), fructose (9-12%), and minor glucose detected. Remarkably, feeding solutions of glucose/fructose (1:1) mixtures did not result in trehalulose/erlose formation. Hence, stingless bees with natural access to floral nectar high in sucrose will produce honey high in trehalulose, with its associated beneficial properties. Any temptation to artificially increase trehalulose content by feeding sucrose to stingless bees would produce "fake" honey lacking key natural phytochemicals available to the foraging bee. The sucrose-fed fake and natural honey were however readily distinguished via isotope ratio mass spectrometry δ 13 C values, to combat such potential indirect adulteration.

• BQCV and SBV were prevalent in apparently healthy adult worker bees (Apis mellifera). • These were also the most commonly detected pathogens in co-foraging native species. • Similar variants were detected across species suggesting interspecies transmission. Australia remains the last significant land mass free of Varroa , a parasitic mite which has caused dramatic honey bee (Apis mellifera) colony losses across the globe, due to its association with the pathogenic deformed wing virus (DWV). As such, Australia continues to maintain relatively healthy honey bee populations, despite recent work showing apiaries harbor a surprisingly high prevalence of microbial pathogens. We sought to determine the prevalence of these microbial pathogens in honey bees and native pollinators actively co-foraging on mass flowering crops and to understand the extent to which they may be shared between taxa. We found high prevalences of black queen cell virus (BQCV) and sacbrood virus (SBV) in the honey bees (88% and 41% respectively), and correspondingly, these were the most common honey bee pathogens detected in native pollinator taxa, albeit at much lower prevalence; the maximum prevalence for any pathogen in a native pollinator group was 24% (BQCV in Halictidae spp.). The viral pathogens Israeli acute paralysis virus and Lake Sinai viruses 1 and 2, and the fungal parasites Nosema apis and Nosema ceranae , were only rarely detected. Phylogenetic analyses of the most common pathogens revealed similar genotypes circulating between species. Our data suggest that, in Australian orchards, pathogen prevalence in honey bees is a good predictor of pathogen prevalence in native pollinators, which raises concerns about how the viral landscape may change in native taxa if, or when, Varroa arrives. [ABSTRACT FROM AUTHOR]

Pyrrolizidine alkaloids (PAs) are a diverse group of plant secondary metabolites with known varied toxicity. Consumption of 1,2-unsaturated PAs has been linked to acute and chronic liver damage, carcinogenicity and death, in livestock and humans, making their presence in food of concern to food regulators in Australia and internationally. In this survey, honey samples sourced from markets and shops in Queensland (Australia), were analysed by high-resolution Orbitrap UHPLC-MS/MS for 30 common PAs. Relationships between the occurrence of pyrrolizidine alkaloids and the botanical origin of the honey are essential as pyrrolizidine alkaloid contamination at up to 3300 ng/g were detected. In this study, the predominant alkaloids detected were isomeric PAs, lycopsamine, indicine and intermedine, exhibiting identical MS/MS spectra, along with lesser amounts of each of their N-oxides. Crucially, chromatographic UHPLC conditions were optimised by operation at low temperature (5 °C) to resolve these key isomeric PAs. Such separation of these isomers by UHPLC, enabled the relative proportions of these PAs present in honey to be compared to alkaloid levels in suspect source plants. Overall plant pyrrolizidine alkaloid profiles were compared to those found in honey samples to help identify the most important plants responsible for honey contamination. The native Australian vines of Parsonsia spp. are proposed as a likely contributor to high levels of lycopsamine in many of the honeys surveyed. Botanical origin information such as this, gained via low temperature chromatographic resolution of isomeric PAs, will be very valuable in identifying region of origin for honey samples. [ABSTRACT FROM AUTHOR]

Antioxidant activity of honeys may be beneficial in wound healing processes by protecting cells against lipid oxidation. The DPPH assay assesses the efficacy of antioxidant molecules to reduce DPPH • to DPPHH. Studies determining EC 50 are limited by single time-point determinations of antioxidant effect and can miss vital information about the rate of antioxidant response. Acquisition of kinetic data allows determination of the radical scavenging capacity (RSC) of honeys. The purpose of this study was to determine the RSC of 53 honeys from 16 species of Australian Eucalyptus trees and four samples of New Zealand manuka (Leptospermum scoparium) honey. Whereas honeys could not be differentiated based on EC 50 values, significant differences were observed for RSC, supporting collection of kinetic data for honey analysis. The greatest RSC was observed for New Zealand manuka (4.6 ± 0.3 × 10 -5 mg.mL -1 .min -1 ), grey ironbark (E. paniculate; 3.4 ± 0.2 × 10 -5 mg.mL -1 .min -1 ) and river red gum honeys (E. camaldulensis; 3.2 ± 0.2 × 10 -5 mg.mL -1 .min -1 )., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Hive design and apicultural processes have not been fundamentally changed since the design and commercialization of the Langstroth moveable frame hive in 1854. Colonies of Apis mellifera Linnaeus (Hymentoptera: Apidae) (the honey bee) maintain a brood nest temperature within the narrow range of 34.5-35.5°C, critical for brood development. Apis mellifera invest considerable energy to maintain hive homeostasis through behavioral modification of the hive environment. Human honey-harvesting processes and removal of the honey-filled comb (a source of thermal mass) have a detrimental impact on hive temperature that requires an increased investment of energy to rectify. This additional energy demand on the bees is a form of stress to the colony and diverts workers away from other essential tasks to that of environmental management. We investigated the thermal energy loss resulting from the removal and extraction of honey, the rate of thermal loss of an Australian standard Langstroth 10 frame hive, and the effect of honey and wax as a thermal mass in unoccupied bee hive. The results demonstrate that considerable energy expenditure would be required to rectify the hive thermal environment after honey harvesting or honeycomb frame addition. Honey provides thermal mass in the beehive, acting as a thermal buffer to external temperature change, which may mediate part of the thermal losses from the simplistic design of the Langstroth hive. Identification of these impacts in current apicultural practice and hive design allows for the improvement in the design of beehives and associated practices. These improvements may reduce stress to the bee colony, increasing colony efficiency for pollination and nectar foraging., (© The Author(s) 2021. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Stingless bee-collected pollen (bee bread) is a mixture of bee pollen, bee salivary enzymes, and regurgitated honey, fermented by indigenous microbes during storage in the cerumen pot. Current literature data for bee bread is overshadowed by bee pollen, particularly of honeybee Apis . In regions such as South America, Australia, and Southeast Asia, information on stingless bee bee bread is mainly sought to promote the meliponiculture industry for socioeconomic development. This review aims to highlight the physicochemical properties and health benefits of bee bread from the stingless bee. In addition, it describes the current progress on identification of beneficial microbes associated with bee bread and its relation to the bee gut. This review provides the basis for promoting research on stingless bee bee bread, its nutrients, and microbes for application in the food and pharmaceutical industries.

A method development for determination of neonicotinoid residues in honey samples was developed. The proposed methodology consisted in QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe). That was used for sample preparation and UHPLC/UV (ultra-performance liquid chromatography with ultraviolet detection) utilized for chromatographic analysis. The developed method proved to be sensitive, with LOD (Limit of detection) value in the range of 60.80 to 80.98 ng/g hence LOQ (Limit of quantification) value was in the range of 184.26 to 245.40 ng/g. The method has tested on Polish honey and applied to honey from various countries (Bulgaria, Czech Republic, France, Greece, Italy, Portugal, Romania, Australia, Brazil, Cameroon, Russia, USA and Turkey). Several honey types were tested, while physicochemical properties of all honeys and were investigated. The methodology for general characterization of pollen grains originated from selected plants, to confirm the type of honey was also presented. There was a total lack of the mentioned neonicotinoids in sunflower honey. Except of this, only two samples of rapeseed and two samples of acacia honey (from Poland and Romania) were neonicotinoids free. In 19 samples the targeted pesticides were detected above LOQ. In all other investigated samples, the neonicotinoids were found at least at the LOD or LOQ level.

Honey adulteration, where a range of sugar syrups is used to increase bulk volume, is a common problem that has significant negative impacts on the honey industry, both economically and from a consumer confidence perspective. This paper investigates High-Performance Thin Layer Chromatography (HPTLC) for the authentication and detection of sugar adulterants in honey. The sugar composition of various Australian honeys (Manuka, Jarrah, Marri, Karri, Peppermint and White Gum) was first determined to illustrate the variance depending on the floral origin. Two of the honeys (Manuka and Jarrah) were then artificially adulterated with six different sugar syrups (rice, corn, golden, treacle, glucose and maple syrup). The findings demonstrate that HPTLC sugar profiles, in combination with organic extract profiles, can easily detect the sugar adulterants. As major sugars found in honey, the quantification of fructose and glucose, and their concentration ratio can be used to authenticate the honeys. Quantifications of sucrose and maltose can be used to identify the type of syrup adulterant, in particular when used in combination with HPTLC fingerprinting of the organic honey extracts.

Honey is an extensively utilized sweetener containing sugars and water, together with small quantities of vitamins, minerals, fatty acids, amino acids and proteins. Naturally produced by honeybees ( Apis mellifera ) from floral nectar, honey is increasingly sold as a health food product due to its nutritious features. Certain honeys are retailed as premium, trendy products. Honeybees are regarded as environmental monitors, but few reports examine the impact of environment on Australian honey trace elements and minerals. In higher density urban and industrial environments, heavy metals can be common, while minerals and trace elements can have ubiquitous presence in both agricultural and urban areas. Honey hives are traditionally placed in rural and forested areas, but increasingly the trend is to keep hives in more urban areas. This study aimed to determine the levels of 26 minerals and trace elements and assess elemental differences between honeys from various regional Queensland and Australian sources. Honey samples (n = 212) were acquired from markets, shops and supermarkets in Queensland while urban honeys were purchased online. The honey samples were classified into four groups according to their regional sources: urban, rural, peri-urban and blend honey. Elemental analyses of honey were performed using ICP-MS and ICP-OES after microwave and hot block digestion. Considerable variations of essential trace elements (Co, Cu, Cr, Fe, Mn, Mo and Zn) and mineral levels (Ca, K, Mg, Na and P) were found in honeys surveyed. There were significant differences ( p < 0.05) between urban and rural honey samples for B, Na, P, Mn, K, Ca and Cu. Significant differences ( p < 0.05) were also found between blend and urban honey samples for K, Cu, P, Mn, Sr, Ni, B and Na. Peri-urban versus urban honeys showed significant differences in P, K and Mn. For rural and peri-urban honeys, the only significant difference ( p < 0.05) was for Na. Toxic heavy metals were detected at relatively low levels in honey products. The study revealed that the Queensland/Australian honey studied is a good source of K and Zn and would constitute a good nutritional source of these elements.

This study is the first large-scale survey of the presence of dihydroxyacetone (DHA) in the nectar of the Australian Leptospermum tree species. The work undertaken supports the growing global demand for bioactive Leptospermum honey. Leptospermum honey derived from L. scoparium in New Zealand, also referred to as Ma̅nuka honey, has a reputation for wound-healing and antimicrobial properties, which is based on its methylglyoxal (MGO) content. High-DHA nectar correlates to high-MGO honey, but not all Leptospermum species produce DHA in their nectar. This study investigates 55 of the 84 Leptospermum species native to Australia for their DHA-producing capability, with the DHA to total sugar (DHA:Tsugar) ratio of nectar samples determined by HPLC-PDA. DHA:Tsugar ranged from nondetectable in L. laevigatum, L. coriaceum, and L. trinervium to >16 000 mg/kg in L. speciosum and L. whitei. High-DHA Leptospermum species were identified for beekeepers to target for honey production and plantation development.

Manuka honey is a product produced essentially in New Zealand, and has been widely recognised for its antibacterial properties and specific taste. In this study, 264 honeys from New Zealand and Australia were analysed using proton NMR spectroscopy coupled with chemometrics. Known manuka markers, methylglyoxal and dihydroxyacetone, have been characterised and quantified, together with a new NMR marker, identified as being leptosperin. Manuka honey profiling using 1H NMR is shown to be a possible alternative to chromatography with the added advantage that it can measure methylglyoxal (MGO), dihydroxyacetone (DHA) and leptosperin simultaneously. By combining the information from these three markers, we established a model to estimate the proportion of manuka in a given honey. Markers of other botanical origins were also identified, which makes 1H NMR a convenient and efficient tool, complementary to pollen analysis, to control the botanical origin of Oceania honeys., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Seasonal variation in metabolic rate and evaporative water loss as a function of ambient temperature were compared in two species of bees. The endemic blue-banded bee, Amegilla chlorocyanea, is a solitary species that is an important pollinator in the south-west Australian biodiversity hotspot. Responses were compared with the European honeybee, Apis mellifera, naturalised in Western Australia almost 200 years ago. Metabolic rate increased exponentially with temperature to a peak in both species, and then declined rapidly, with unique scaling exponents and peaks for all species-by-season comparisons. Early in the austral summer, Apis was less thermally tolerant than Amegilla, but the positions reversed later in the foraging season. There were also significant exponential increases in evaporative water loss with increasing temperature, and both season and species contributed to significantly different responses. Apis maintained relatively consistent thermal performance of metabolic rate between seasons, but at the expense of increased rates of evaporative water loss later in summer. In contrast, Amegilla had dramatically increased metabolic requirements later in summer, but maintained consistent thermal performance of evaporative water loss. Although both species acclimated to higher thermal tolerance, the physiological strategies underpinning the acclimation differed. These findings may have important implications for understanding the responses of these and other pollinators to changing environments and for their conservation management.

Background: Although sentinel animals are used successfully throughout the world to monitor arbovirus activity, ethical considerations and cross-reactions in serological assays highlight the importance of developing viable alternatives. Here we outline the development of a passive sentinel mosquito arbovirus capture kit (SMACK) that allows for the detection of arboviruses on honey-baited nucleic acid preservation cards (Flinders Technology Associates; FTA®) and has a similar trap efficacy as standard light traps in our trials., Methods: The trap efficacy of the SMACK was assessed against Centers for Disease Control and Prevention (CDC) miniature light traps (standard and ultraviolet) and the Encephalitis Vector Survey (EVS) trap in a series of Latin square field trials conducted in North Queensland, Australia. The ability of the SMACK to serve as a sentinel arbovirus surveillance tool was assessed in comparison to Passive Box Traps (PBT) during the 2014 wet season in the Cairns, Australia region and individually in the remote Northern Peninsula Area (NPA) of Australia during the 2015 wet season., Results: The SMACK caught comparable numbers of mosquitoes to both CDC light traps (mean capture ratio 0.86: 1) and consistently outperformed the EVS trap (mean capture ratio 2.28: 1) when CO2 was supplied by either a gas cylinder (500 ml/min) or dry ice (1 kg). During the 2014 arbovirus survey, the SMACK captured significantly (t 6 = 2.1, P = 0.04) more mosquitoes than the PBT, and 2 and 1 FTA® cards were positive for Ross River virus and Barmah Forest virus, respectively, while no arboviruses were detected from PBTs. Arbovirus activity was detected at all three surveillance sites during the NPA survey in 2015 and ca. 27 % of FTA® cards tested positive for either Murray Valley encephalitis virus (2 detections), West Nile virus (Kunjin subtype; 13 detections), or both viruses on two occasions., Conclusions: These results demonstrate that the SMACK is a versatile, simple, and effective passive arbovirus surveillance tool that may also be used as a traditional overnight mosquito trap and has the potential to become a practical substitute for sentinel animal programs.

The nonperoxide antibacterial activity of New Zealand ma̅nuka honey originates from dihydroxyacetone (DHA) within Leptospermum scoparium nectar. This study determined if DHA was present within the nectar of four Australian Leptospermum species: L. laevigatum, L. polygalifolium, L. trinervium, and L. whitei. A rapid and convenient new method was developed, which quantitated DHA/sugar ratios (ppm). The DHA and sugars were derivatized with o-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine hydrochloride and analyzed via RP-HPLC with diode array detection at two wavelengths (200 and 243 nm). DHA was detected in all L. whitei and L. polygalifolium samples, where DHA/sugar ratios ranged from 10169 to 24199 ppm and from 9321 to 20174 ppm, respectively. DHA was undetected in any of the L. laevigatum and L. trinervium samples, and nectar activity was <100 ppm. The results of this study have implications for the Australian beekeeping industry, as the findings indicated that not all species of Leptospermum will produce active honey.

Honey samples originating from Australia were purchased and analysed for targeted pyrrolizidine alkaloids (PAs) using a new and rapid isocratic LC-MS/MS method. This isocratic method was developed from, and is comparable with, a gradient elution method and resulted in no loss of sensitivity or reduction in chromatographic peak shape. Isocratic elution allows for significantly shorter run times (6 min), eliminates the requirement for column equilibration periods and, thus, has the advantage of facilitating a high-throughput analysis which is particularly important for regulatory testing laboratories. In excess of two hundred injections are possible, with this new isocratic methodology, within a 24-h period which is more than 50% improvement on all previously published methodologies. Good linear calibrations were obtained for all 10 PAs and four PA N-oxides (PANOs) in spiked honey samples (3.57-357.14 µg l(-1); R(2) ≥ 0.9987). Acceptable inter-day repeatability was achieved for the target analytes in honey with % RSD values (n = 4) less than 7.4%. Limits of detection (LOD) and limits of quantitation (LOQ) were achieved with spiked PAs and PANOs samples; giving an average LOD of 1.6 µg kg(-1) and LOQ of 5.4 µg kg(-1). This method was successfully applied to Australian and New Zealand honey samples sourced from supermarkets in Australia. Analysis showed that 41 of the 59 honey samples were contaminated by PAs with the mean total sum of PAs being 153 µg kg(-1). Echimidine and lycopsamine were predominant and found in 76% and 88%, respectively, of the positive samples. The average daily exposure, based on the results presented in this study, were 0.051 µg kg(-1) bw day(-1) for adults and 0.204 µg kg(-1) bw day(-1) for children. These results are a cause for concern when compared with the proposed European Food Safety Authority (EFSA), Committee on Toxicity (COT) and Bundesinstitut für Risikobewertung (BfR - Federal Institute of Risk Assessment Germany) maximum daily PA intake limit of 0.007 µg kg(-1) bw day(-1).