A Comparative Characterization of Physicochemical and Antioxidants Properties of Processed Heterotrigona itama Honey from Different Origins and Classification by Chemometrics Analysis

Physicochemical Characteristics, Antioxidant Capacity, and Antimicrobial Activity of Stingless Bee Honey from Malaysia: Heterotrigona itama, Lophotrigona canifrons, and Tetrigona binghami

The composition and bioactivity of honey are influenced by its botanical, geographical, and entomological origins. This study investigates the physicochemical characteristics, antioxidant capacity, and antimicrobial activity of stingless bee honey (SBH) produced by three Malaysian stingless bee species: Heterotrigona itama, Lophotrigona canifrons, and Tetrigona binghami. The moisture content ranges from 25.44% to 40.36%, while the honey color varies from light amber to dark amber. The fructose, glucose, and sucrose contents range from 5.45 to 16.91 g/100 g, 3.85 to 19.64 g/100 g, and undetectable to 2.47 g/100 g, respectively. Trehalulose is present at a level of 15.42 to 43.75 g/100 g, with L. canifrons honey exhibiting the highest trehalulose concentration. All samples show low 5-HMF content and no detectable diastase activity. T. binghami honey has the lowest pH, highest electricity conductivity and acidity, and exhibits the strongest antimicrobial activity against Staphylococcus aureus and Escherichia coli. H. itama honey exhibits the highest antioxidant potential based on ABTS, FRAP, and DPPH assays. Among the three species, L. canifrons honey contains the highest total phenolic content. These findings provide valuable insights into the unique properties of SBH, supporting further research, quality assessment, and the development of international standards.

Application of Doehlert design combined with chemometrics tools: Example of the optimization of the elution of neurotransmitters and metabolites by HPLC

Experimental designs are essential mathematical tools in fields like agronomy, chemistry, and analytical chemistry for optimizing processes and minimizing variations. Doehlert designs, in particular, are valued for their efficiency in exploring experimental space with minimal experiments, providing detailed insights into complex processes. In analytical chemistry, these designs are extensively used for tasks such as extraction, purification, and method optimization, allowing systematic variation of factors to enhance accuracy and efficiency. To further optimize the method, a combination of experimental design and chemometric tools is necessary to understand the chromatographic behavior of the compounds of interest. This study uses Doehlert experimental design combined with chemometric tools to optimize the elution and separation of neurotransmitters and their metabolites using HPLC-ECD. Pearson correlation and Partial Least Squares Discriminant Analysis (PLS-DA) reveal significant relationships between chromatographic parameters and experimental conditions. Notably, the pH of the mobile phase significantly impacts column efficiency and elution time, while the polarity index and pressure influence peak asymmetry. Optimized conditions include a mobile phase of ACN/MeOH/H2O (11.25/3.25/85.5; v/v/v) with a pH near 1.65, achieving optimal elution times around 20 min, column efficiency with a mean number of theoretical plates close to 8000, and peak asymmetry of approximately 1.23. The limits of detection and quantification of interest compounds are close to 10-11 and 10-10 mol L-1 respectively. This new combined approach allows for effective, rapid, and resolved elution of compounds, reducing resource consumption and time. Moreover, the combination of parameters has been taken into account with chemometrics, allowing a highly effective enhancement of compound elution. The optimized method achieves low detection and quantification limits in the nanomolar range, making it suitable for precise neurotransmitter analysis in complex biological samples.

A report on the physicochemical and antioxidant properties of three Indonesian forest honeys produced by Apis dorsata

Indonesia, one of the largest tropical forests, offers a diverse range of nectar sources that contribute to the unique characteristics of forest honey. This study aims to investigate physicochemical and antioxidant properties of Apis dorsata forest honey from three distinct regions of Indonesia. Key physicochemical parameters include moisture, color, electrical conductivity (EC), total dissolved solids (TDS), total suspended solids (TSS), density, diastase number (DN), hydroxymethylfurfural (HMF), pH, total acidity, ash content, protein content, and reducing sugars. Antioxidant properties, assessed through total phenolic content (TPC), total flavonoid content (TFC), DPPH radical scavenging activity, ascorbic acid equivalent antioxidant capacity (AEAC), and ferric reducing power (FRP), revealed significant regional variability. Principal component analysis (PCA) distinguished honey samples based on these attributes. These findings provide preliminary insights into the variability of Indonesian forest honeys. However, the small sample size limits generalizations, and further research with larger datasets is essential for validation.

Honey Enriched with Additives Alleviates Behavioral, Oxidative Stress, and Brain Alterations Induced by Heavy Metals and Imidacloprid in Zebrafish

Environmental concerns have consistently been a focal point for the scientific community. Pollution is a critical ecological issue that poses significant threats to human health and agricultural production. Contamination with heavy metals and pesticides is a considerable concern, a threat to the environment, and warrants special attention. In this study, we investigated the significant issues arising from sub-chronic exposure to imidacloprid (IMI), mercury (Hg), and cadmium (Cd), either alone or in combination, using zebrafish (Danio rerio) as an animal model. Additionally, we assessed the potential protective effects of polyfloral honey enriched with natural ingredients, also called honey formulation (HF), against the combined sub-chronic toxic effects of the three contaminants. The effects of IMI (0.5 mg·L-1), Hg (15 μg·L-1), and Cd (5 μg·L-1), both individually and in combination with HF (500 mg·L-1), on zebrafish were evaluated by quantifying acetylcholinesterase (AChE) activity, lipid peroxidation (MDA), various antioxidant enzyme activities like superoxide dismutase and glutathione peroxidase (SOD and GPx), 2D locomotor activity, social behavior, histological and immunohistochemical factors, and changes in body element concentrations. Our findings revealed that all concentrations of pollutants may disrupt social behavior, diminish swimming performances (measured by total distance traveled, inactivity, and swimming speed), and elevate oxidative stress (OS) biomarkers of SOD, GPx, and MDA in zebrafish over the 21-day administration period. Fish exposed to IMI and Hg + Cd + IMI displayed severe lesions and increased GFAP (Glial fibrillary acidic protein) and S100B (S100 calcium-binding protein B) protein expression in the optic tectum and cerebellum, conclusively indicating astrocyte activation and neurotoxic effects. Furthermore, PCNA (Proliferating cell nuclear antigen) staining revealed reduced cell proliferation in the IMI-exposed group, contrasting with intensified proliferation in the Hg + Cd group. The nervous system exhibited significant damage across all studied concentrations, confirming the observed behavioral changes. Moreover, HF supplementation significantly mitigated the toxicity induced by contaminants and reduced OS. Therefore, the exposure to chemical mixtures offers a more complete picture of adverse impacts on aquatic ecosystems and the supplementation with bioactive compounds can help to reduce the toxicity induced by exposure to environmental pollutants.

Effect on the Antioxidant Properties of Native Chilean Endemic Honeys Treated with Ionizing Radiation to Remove American Foulbrood Spores

In Chile, honey is produced from several native species with interesting biological properties. Accordingly, those attributes are present in Chilean honeys owing to the presence of phenolic compounds inherited from specific floral sources. In recent years, the exported volume of Chilean honeys has been increased, reaching new markets with demanding regulations directed toward the fulfilment of consumers' expectations. Accordingly, there are countries with special requirements referring to Paenibacillus larvae spore-free honeys. This microorganism is the pathogen responsible for American foulbrood disease in beehives; however, antibiotics are not allowed when an apiary tests positive for P. larvae. On the other hand, it is mandatory to have an accurate method to remove the potential presence of spores in bee products intended for export. Exposure to ionizing radiation can be an efficient way to achieve this goal. In this work, 54 honey samples harvested from northern, central and southern Chile were analyzed for physicochemical patterns, total phenols, antioxidant activity and antiradical activity. Honeys with and without spores were exposed to ionizing radiation at three levels of intensity. Afterwards, the presence of spores and the effect on phenol bioavailability, antiradical activity and antioxidant activity were measured again. This research presents results showing a positive correlation between the percentage of prevalence of native endemic species in the set of honeys analyzed and the capacity to resist this process, without altering their natural attributes determined before irradiation treatments.

Antioxidant Activity, Physicochemical and Sensory Properties of Stingless Bee Honey from Australia

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.

Hepatic and renal effects of oral stingless bee honey in a streptozotocin-induced diabetic rat model

BACKGROUND

Diabetes is known damage the liver and kidney, leading to hepatic dysfunction and kidney failure. Honey is believed to help in lowering the blood glucose levels of diabetic patients and reducing diabetic complications. However, the effect of stingless bee honey (SBH) administration in relieving liver and kidney damage in diabetes has not been well-studied.

AIM

To investigate the effect of SBH administration on the kidney and liver of streptozotocin-induced (STZ; 55 mg/kg) diabetic Sprague Dawley rats.

METHODS

The rats were grouped as follows (n = 6 per group): non-diabetic (ND), untreated diabetic (UNT), metformin-treated (MET), and SBH+metformin-treated (SBME) groups. After successful diabetic induction, ND and UNT rats were given normal saline, whereas the treatment groups received SBH (2.0 g/kg and/or metformin (250 mg/kg) for 12 d. Serum biochemical parameters and histological changes using hematoxylin and eosin (H&E) and periodic acid-Schiff (PAS) staining were evaluated.

RESULTS

On H&E and PAS staining, the ND group showed normal architecture and cellularity of Bowman's capsule and tubules, whereas the UNT and MET groups had an increased glomerular cellularity and thickened basement membrane. The SBH-treated group showed a decrease in hydropic changes and mild cellularity of the glomerulus vs the ND group based on H&E staining, but the two were similar on PAS staining. Likewise, the SBME-treated group had an increase in cellularity of the glomerulus on H&E staining, but it was comparable to the SBH and ND groups on PAS staining. UNT diabetic rats had tubular hydropic tubules, which were smaller than other groups. Reduced fatty vacuole formation and dilated blood sinusoids in liver tissue were seen in the SBH group. Conversely, the UNT group had high glucose levels, which subsequently increased MDA levels, ultimately leading to liver damage. SBH treatment reduced this damage, as evidenced by having the lowest fasting glucose, serum alanine transaminase, aspartate transaminase, and alkaline phosphatase levels compared to other groups, although the levels of liver enzymes were not statistically significant.

CONCLUSION

The cellularity of the Bowman's capsule, as well as histological alteration of kidney tubules, glomerular membranes, and liver tissues in diabetic rats after oral SBH resembled those of ND rats. Therefore, SBH exhibited a protective hepatorenal effect in a diabetic rat model.

Physicochemical homogeneity of stingless bee honey (Heterotrigona itama) produced in the west coast, east coast and inland area of Peninsular Malaysia

BACKGROUND

The nutritional composition of stingless bee honey (SBH) can be affected by different climates and soil composition across different geographical areas. However, the range of attributes set for a honey quality standard should be inclusive. This study analysed the sugar profile's physiochemical properties, including quantifying the rare sugar trehalulose, organic acid and mineral composition of SBH collected from inland, and west and east coasts of Peninsular Malaysia. Forty-three SBH (Heterotrigona itama) samples were collected and labelled as <20 and <40 West Coast (<20WC, <40WC), <20 and <40 East Coast (<20EC, <40EC) and Inland, according to their distance from the coasts.

RESULTS

The moisture, pH and sugar composition of all SBH samples adhered to the Malaysian Kelulut Honey Standard (MS2683:2017) but not to the International Codex Standard (CODEX) for honey. Trehalulose presence in all samples, regardless of geographical area, was predominant alongside fructose and glucose. Only hydroxymethylfurfural (HMF) content and electrical conductivity (EC) results complied with both standards. The principal component analysis biplot showed that the discrimination of SBH according to the five different areas was not feasible, indicating sample homogeneity.

CONCLUSION

The physicochemical evaluation of SBH from Peninsular Malaysia shows mainly homogeneous attributes of samples across geographical locations. These findings demonstrated that the current MS2683:2017 is relevant and accommodates all SBH of H. itama species produced in Peninsular Malaysia. Furthermore, the trehalulose range calculated in this study can be implemented as a new benchmark for the indicator of SBH honey quality standard by national and international food standard committees. © 2023 Society of Chemical Industry.

Exploring stingless bee honey from selected regions of Peninsular Malaysia through gas chromatography-mass spectrometry-based untargeted metabolomics

Volatile organic compounds in honey are known for their considerable impact on the organoleptic properties of honey, such as aroma, flavor, taste, and texture. The type and composition of volatile organic compounds are influenced by entomological, geographical, and botanical origins; thus, these compounds have the potential to be chemical markers. Sixty-two volatile compounds were identified using gas chromatography-mass spectrometry from 30 Heterotrigona itama (H. itama) honey samples from 3 different geographical origins. Hydrocarbons and benzene derivatives were the dominant classes of volatile organic compounds in the samples. Both clustering and discriminant analyses demonstrated a clear separation between samples from distant origins (Kedah and Perak), and the volcano plot supported it. The reliability and predictability of the partial least squares-discriminant analysis model from the discriminant analysis were validated using cross-validation (R2 : 0.93; Q2 : 0.83; accuracy: 0.97) and the permutation test (p < 0.001), and the output depicted that the model is legitimate. In combination with the variable importance of projection (VIP > 1.0) and the Kruskal-Wallis test (p < 0.01), 19 volatile organic compounds (encompassed aldehydes, benzene derivatives, esters, hydrocarbons, and terpenoids) were sorted and named potent chemical markers in classifying honey samples from three geographical origins. In brief, this study illustrated that volatile organic compounds of stingless honey originated from the same bee species, but different geographical origins could be applied as chemical markers.

Non-Targeted Detection and Quantification of Food Adulteration of High-Quality Stingless Bee Honey (SBH) via a Portable LED-Based Fluorescence Spectroscopy

Stingless bee honey (SBH) is rich in phenolic compounds and available in limited quantities. Authentication of SBH is important to protect SBH from adulteration and retain the reputation and sustainability of SBH production. In this research, we use portable LED-based fluorescence spectroscopy to generate and measure the fluorescence intensity of pure SBH and adulterated samples. The spectrometer is equipped with four UV-LED lamps (peaking at 365 nm) as an excitation source. Heterotrigona itama, a popular SBH, was used as a sample. 100 samples of pure SBH and 240 samples of adulterated SBH (levels of adulteration ranging from 10 to 60%) were prepared. Fluorescence spectral acquisition was measured for both the pure and adulterated SBH samples. Principal component analysis (PCA) demonstrated that a clear separation between the pure and adulterated SBH samples could be established from the first two principal components (PCs). A supervised classification based on soft independent modeling of class analogy (SIMCA) achieved an excellent classification result with 100% accuracy, sensitivity, specificity, and precision. Principal component regression (PCR) was superior to partial least squares regression (PLSR) and multiple linear regression (MLR) methods, with a coefficient of determination in prediction (R2p) = 0.9627, root mean squared error of prediction (RMSEP) = 4.1579%, ratio prediction to deviation (RPD) = 5.36, and range error ratio (RER) = 14.81. The LOD and LOQ obtained were higher compared to several previous studies. However, most predicted samples were very close to the regression line, which indicates that the developed PLSR, PCR, and MLR models could be used to detect HFCS adulteration of pure SBH samples. These results showed the proposed portable LED-based fluorescence spectroscopy has a high potential to detect and quantify food adulteration in SBH, with the additional advantages of being an accurate, affordable, and fast measurement with minimum sample preparation.

Phytochemical Compounds of Raw Versus Methanol-Extracted Kelulut, Tualang, and Manuka Honeys

Honey has been widely used for medicinal purposes since ancient times. It is produced by stinging bees or stingless bees by processing the collected nectar or plant sap in their bodies into raw honey. Extraction of honey will result in the pooling of crude volatile bioactive materials that could enhance its benefits. This work aims to compare the phytochemical characteristics of raw and methanol-extracted honeys in the Kelulut, Tualang and Manuka honeys. All types of raw honey samples were extracted by using the methanol extraction method and both groups were analysed using gas chromatography/mass spectrometry (GC/MS) at the National Poison Centre, Universiti Sains Malaysia, Malaysia. The findings showed that 23 compounds were identified in raw Kelulut honey and 18 compounds in methanol-extracted Kelulut honey; 28 compounds were identified in raw Tualang honey and 29 compounds in methanol-extracted Tualang honey; 19 compounds in raw Manuka honey and 22 compounds in methanol-extracted Manuka honey. There were differences in the phytochemical substances detected in raw and methanol-extracted honeys. The major compounds in raw honeys were mostly from the ketone, alcohol, and ester groups, whereas the ketone group was dominant in methanol-extracted honeys. Most bioactive substances identified in the methanol-extracted variant of honeys were more concentrated than the raw variant. A majority of these substances have antimicrobial characteristics.

Quality assessment and chemometrics application on physicochemical characteristics, antioxidant properties, and 5-HMF content of Malaysian stingless bee honey from different topographical origins

The popularity of Malaysian stingless bee honey is rising among health-conscious individuals; thus, chemical and physical evaluations of Malaysian stingless bee honey are vital to ensure the honey has achieved the optimum limits set by Malaysian and international regulatory standards so that it can be commercialized locally and internationally. Therefore, in the present study, the physicochemical characteristics (moisture content, total dissolved solids, pH, free acidity, electrical conductivity, and ash content), antioxidant properties (total phenolic and flavonoid contents), and 5-hydroxymethylfurfural (5-HMF) of Heterotrigona itama (H. itama) honey from different sites in Peninsular Malaysia were investigated. Subsequently, the correlation between these chemical and physical parameters was studied using Spearman correlation coefficients. The significant difference between H. itama honey from different topographical origins was studied using univariate analysis (one-way ANOVA followed by post hoc Tukey's test). The discrimination pattern of 45 honey samples based on their topographical origins was evaluated using cluster analysis (heatmap and dendrogram) and chemometrics analysis (partial least squares-discriminant analysis). Results showed that some samples of certain parameters (electrical conductivity, free acidity, and moisture content) have exceeded the limit set by the international regulatory standard. However, the 5-HMF content of all samples was within the allowed range. A statistically significant difference (p < 0.05) has been observed for all the parameters except electrical conductivity and ash content in terms of inter-topographical origins. Although the profiles of H. itama honey from different origins were close, most of them were separated according to their topographical origins and were validated using a permutation test.

The potential neuroprotective effects of stingless bee honey

Tropical Meliponini bees produce stingless bee honey (SBH). Studies have shown beneficial properties, including antibacterial, bacteriostatic, anti-inflammatory, neurotherapeutic, neuroprotective, wound, and sunburn healing capabilities. High phenolic acid and flavonoid concentrations offer SBH its benefits. SBH can include flavonoids, phenolic acids, ascorbic acid, tocopherol, organic acids, amino acids, and protein, depending on its botanical and geographic origins. Ursolic acid, p-coumaric acid, and gallic acid may diminish apoptotic signals in neuronal cells, such as nuclear morphological alterations and DNA fragmentation. Antioxidant activity minimizes reactive oxygen species (ROS) formation and lowers oxidative stress, inhibiting inflammation by decreasing enzymes generated during inflammation. Flavonoids in honey reduce neuroinflammation by decreasing proinflammatory cytokine and free radical production. Phytochemical components in honey, such as luteolin and phenylalanine, may aid neurological problems. A dietary amino acid, phenylalanine, may improve memory by functioning on brain-derived neurotrophic factor (BDNF) pathways. Neurotrophin BDNF binds to its major receptor, TrkB, and stimulates downstream signaling cascades, which are crucial for neurogenesis and synaptic plasticity. Through BDNF, SBH can stimulate synaptic plasticity and synaptogenesis, promoting learning and memory. Moreover, BDNF contributes to the adult brain's lasting structural and functional changes during limbic epileptogenesis by acting through the cognate receptor tyrosine receptor kinase B (TrkB). Given the higher antioxidants activity of SBH than the Apis sp. honey, it may be more therapeutically helpful. There is minimal research on SBH's neuroprotective effects, and the related pathways contribute to it is unclear. More research is needed to elucidate the underlying molecular process of SBH on BDNF/TrkB pathways in producing neuroprotective effects.

Physicochemical Characteristics and Bioactive Compounds of Different Types of Honey and Their Biological and Therapeutic Properties: A Comprehensive Review

Honey is considered to be a functional food with health-promoting properties. However, its potential health benefits can be affected by individual composition that varies between honey types. Although studies describing the health benefits of Tualang honey (TH), Kelulut honey (KH), and Sidr honey (SH) are scarce, these honey types showed a comparable therapeutic efficacy to Manuka honey (MH). The purpose of this review is to characterise the physicochemical, biological, and therapeutic properties of TH, KH, and SH. Findings showed that these honeys have antibacterial, antifungal, antiviral, antioxidant, antidiabetic, antiobesity, anticancer, anti-inflammatory and wound-healing properties and effects on the cardiovascular system, nervous system, and respiratory system. The physicochemical characteristics of TH, KH, and SH were compared with MH and discussed, and results showed that they have high-quality contents and excellent biological activity sources. Flavonoids and polyphenols, which act as antioxidants, are two main bioactive molecules present in honey. The activity of honey depends on the type of bee, sources of nectar, and the geographic region where the bees are established. In conclusion, TH, KH, and SH could be considered as natural therapeutic agents for various medicinal purposes compared with MH. Therefore, TH, KH, and SH have a great potential to be developed for modern medicinal use.

Insight into the Recent Application of Chemometrics in Quality Analysis and Characterization of Bee Honey during Processing and Storage

The application of chemometrics, a widely used science in food studies (and not only food studies) has begun to increase in importance with chemometrics being a very powerful tool in analyzing large numbers of results. In the case of honey, chemometrics is usually used for assessing honey authenticity and quality control, combined with well-established analytical methods. Research related to investigation of the quality changes in honey due to modifications after processing and storage is rare, with a visibly increasing tendency in the last decade (and concentrated on investigating novel methods to preserve the honey quality, such as ultrasound or high-pressure treatment). This review presents the evolution in the last few years in using chemometrics in analyzing honey quality during processing and storage. The advantages of using chemometrics in assessing honey quality during storage and processing are presented, together with the main characteristics of some well-known chemometric methods. Chemometrics prove to be a successful tool to differentiate honey samples based on changes of characteristics during storage and processing.

Effect of harvest time span on physicochemical properties, antioxidant, antimicrobial, and anti-inflammatory activities of Meliponinae honey

BACKGROUND

The maturity of honey has a great impact on its quality and contents. Additionally, stingless bee honey contains high moisture, which allows microorganisms to survive and ferment, contributing to honey's variable flavor and physicochemical properties. Therefore, there is a need for better quality control of the honey process, especially the harvest time of honey.

RESULTS

We gathered honey from the nest of stingless bees Heterotrigona itama and Tetrigona binghami over different time periods, i.e. 15, 30, and 45 days. The results show harvest time considerably affects the physicochemical properties, antioxidant activity, and antimicrobial activity of honey. Good antioxidant activity and antimicrobial activity can be found in honey produced from a longer harvest time. Compared with 15-day harvest time, at 30- or 45-day harvest time water, trehalulose, and protein content and total acidity increased, and the content of reducing sugars, fructose and glucose, and pH values, decreased in both types of honey. Moreover, compared with 15-day harvest time, the sum of six organic acids in the 45-day honey of H. itama fluctuated between 2.78 to 4.12 g 100 g^-1 and in the 45-day honey of T. binghami increased from 1.66 to 3.61 g 100 g^-1 , respectively.

CONCLUSION

Honey harvest time had a significant effect on the physicochemical properties, antioxidant activity, and antimicrobial activity of stingless bee honey (H. itama or T. binghami). This study provides a reference for beekeepers to adjust harvest time to obtain honey with suitable physicochemical parameters. © 2022 Society of Chemical Industry.

Kelulut Honey Ameliorates Oestrus Cycle, Hormonal Profiles, and Oxidative Stress in Letrozole-Induced Polycystic Ovary Syndrome Rats

Kelulut honey (KH) has been proven to have excellent antioxidative and anti-inflammatory properties with unique physicochemical characteristics. Therefore, we investigated the isolated and combined effects of KH, metformin, or clomiphene in alleviating oxidative stress and reproductive and metabolic abnormalities in polycystic ovary syndrome (PCOS). Female Sprague-Dawley (SD) rats were given 1 mg/kg/day of letrozole for 21 days to induce PCOS. PCOS rats were then divided into six treatment groups: untreated, metformin (500 mg/kg/day), clomiphene (2 mg/kg/day), KH (1 g/kg/day), combined KH (1 g/kg/day) and metformin (500 mg/kg/day), and combined KH (1 g/kg/day) and clomiphene (2 mg/kg/day). All treatments were administered orally for 35 days. The physicochemical characteristics of KH were assessed through hydroxymethylfurfural, free acidity, diastase number, moisture content, sugar profile, metals, and mineral compounds. Additionally, we determined the semivolatile organic compounds present in KH through gas chromatography-mass spectrometry (GC/MS) analysis. KH and its combination with metformin or clomiphene were shown to improve the oestrus cycle, hormonal profile, and oxidative stress in PCOS rats. However, KH did not reduce the fasting blood glucose, insulin, and body weight gain in PCOS rats. These findings may provide a basis for future studies to discover the potential use of KH as a complementary treatment for women with PCOS.

Physicochemical Properties of a New Green Honey from Banggi Island, Sabah

Green honey is exclusively available on the island of Banggi in Sabah, and its uniqueness sees the commodity being sold at a high market price. Therefore, green honey is prone to adulteration by unscrupulous individuals, possibly compromising the health of those consuming this food commodity for its curative properties. Moreover, an established standard for reducing sugar in green honey is unavailable. Ipso facto, the study aimed to profile green honey’s physical and chemical properties, such as its pH, moisture content, free acidity, ash content, electroconductivity, hydroxymethylfurfural (HMF), total phenolic content, total flavonoid content, DPPH, colour, total sugar content, total protein content, and heavy metals as well as volatile organic compounds, the data of which are profoundly valuable in safeguarding consumers’ safety while providing information for its quality certification for local consumption and export. The results revealed that the honey’s physicochemical profile is comparable to other reported kinds of honey. The honey’s naturally green colour is because of the chlorophyll from the nectar from various flowers on the island. The raw honey showed free acidity between 28 and 33 Meq/100 g, lower than the standard’s 50 Meq/100 g. The hydroxymethylfurfural content is the lowest compared to other reported honey samples, with the total phenolic content between 16 and 19 mg GAE/100 g. The honey’s reducing sugar content is lower (~37.9%) than processed ones (56.3%) because of water removal. The protein content ranged from 1 to 2 gm/kg, 4- to 6-fold and 2-fold higher than local and manuka honey, respectively. The exceptionally high content of trans-4-hydroxyproline in raw honey is its source of collagen and other healing agents. Interestingly, low levels of arsenic, lead, nickel, cadmium, copper, and cobalt were detected in the honey samples, presumably due to their subterranean hives. Nevertheless, the honey is fit for general consumption as the concentrations were below the maxima in the Codex Alimentarius Commission of 2001.

Effects of Kelulut Honey on Oestrus Cycle Regulation and Histomorphological Changes in Letrozole-Induced Polycystic Ovary Syndrome Rats: A Preliminary Study

Polycystic ovary syndrome (PCOS) is a complex reproductive, metabolic, and endocrine disorder that affects women of reproductive age. Kelulut honey is stingless bee honey that possesses anti-inflammatory, anti-cancer, anti-diabetic, and potent antioxidative activities in most conditions. However, its value in improving PCOS remains to be elucidated. Thus, this preliminary study aimed to determine the effective dose of Kelulut honey in oestrus cycle regulation and ovarian histomorphological changes in letrozole-induced PCOS rats. PCOS was induced in all-female Sprague Dawley (SD) rats with 1 mg/kg/day of letrozole except for the control group for 21 days. Kelulut honey was then orally administered to the PCOS rats at the dose of 0.5, 1, or 2 g/kg/day, respectively, for 35 days. The oestrous cycle was determined through vaginal smears, while ovarian histomorphological changes were observed by haematoxylin and eosin (H&E) staining. The untreated PCOS rats were characterised by irregular oestrous cyclicity, hyperglycaemia, and aberrant ovarian histology. In this study, Kelulut honey (1 g/kg/day) increased the number of corpus luteum and antral follicles (p < 0.05), improved the cystic follicle, and normalised the oestrus cycle (p < 0.05). This preliminary study demonstrated that Kelulut honey, particularly at a dose of 1 g/kg/day, has the potential to alleviate oestrus cycle dysregulation and ovarian histomorphological changes occurring in PCOS.

Application of Heating on the Antioxidant and Antibacterial Properties of Malaysian and Australian Stingless Bee Honey

In the honey industry, heat treatments are usually applied to maintain honey’s quality and shelf life. Heat treatment is used to avoid crystallisation and allow the easy use of honey, but treatment with heat might affect the antioxidant and antibacterial activities, which are the immediate health effects of honey. This study will determine the effect of heat treatment on Malaysian and Australian stingless bee honey (SBH) produced by the common bee species in both countries. Eighteen honey samples were subjected to heat at 45 °C, 55 °C and 65 °C for one hour and subsequently analysed for their total phenolic content (TPC), total flavonoid content (TFC), DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP) and minimum inhibitory concentration (MIC). The results show that all samples had high TPC, TFC and antioxidant activities before the treatment. The heat treatments did not affect (p < 0.05) the TPC, TFC and antioxidant activities in most samples, but did inhibit the antibacterial activities consistently in most of the samples, regardless of the bee species and country of origin. This study also confirms a strong correlation between TPC and TFC with FRAP activities for the non-heated and heated honey samples (p < 0.05). Other heat-sensitive bioactive compounds in SBH should be measured to control the antibacterial properties present.

In Vivo Toxicity Evaluation of Sugar Adulterated Heterotrigona itama Honey Using Zebrafish Model

Honey is prone to be adulterated through mixing with sugars, cheap and low-quality honey, and other adulterants. Consumption of adulterated honey may cause several health issues such as weight gain, diabetes, and liver and kidney dysfunction. Therefore, studying the impact of consumption of adulterated honey on consumers is critical since there is a lack of study in this field. Hence, the aims of this paper were: (1) to determine the lethal concentration (LC₅₀) of adulterated honey using zebrafish embryo, (2) to elucidate toxicology of selected adulterated honey based on lethal dose (LD₅₀) using adult zebrafish, (3) to determine the effects of adulterated honey on histological changes of zebrafish, and (4) to screen the metabolites profile of adulterated honey by using zebrafish blood serum. The LC₅₀ of Heterotrigona itama honey (acacia honey) and its sugar adulterants (light corn sugar, cane sugar, inverted sugar, and palm sugar in the proportion of 1-3% (w/w) from the total volume) was determined by the toxicological assessment of honey samples on zebrafish embryos (different exposure concentrations in 24, 48, 72, and 96 h postfertilization (hpf)). Pure H. itama honey represents the LC₅₀ of 34.40 ± 1.84 (mg/mL) at 96 hpf, while the inverted sugar represents the lowest LC₅₀ (5.03 ± 0.92 mg/mL) among sugar adulterants. The highest concentration (3%) of sugar adulterants were used to study the toxicology of adulterated honey using adult zebrafish in terms of acute, prolong-acute, and sub-acute tests. The results of the LD₅₀ from the sub-acute toxicity test of pure H. itama honey was 2.33 ± 0.24 (mg/mL). The histological studies of internal organs showed a lesion in the liver, kidney, and spleen of adulterated treated-honey groups compared to the control group. Furthermore, the LC-MS/MS results revealed three endogenous metabolites in both the pure and adulterated honey treated groups, as follows: (1) S-Cysteinosuccinic acid, (2) 2,3-Diphosphoglyceric acid, and (3) Cysteinyl-Tyrosine. The results of this study demonstrated that adulterated honey caused mortality, which contributes to higher toxicity, and also suggested that the zebrafish toxicity test could be a standard method for assessing the potential toxicity of other hazardous food additives. The information gained from this research will permit an evaluation of the potential risk associated with the consumption of adulterated compared to pure honey.

Addition of Honey to an Apple and Passion Fruit Mixed Beverage Improves Its Phenolic Compound Profile

The addition of honey to mixed beverages is interesting due to its contribution to the sweet taste, as well as because it is a dietary source of bioactive compounds. In this study, we investigated the chemical composition and sensory acceptance of an apple and passion fruit mixed beverage with added honey. The addition of honey did not produce a noticeable change in instrumental color but led to an increase in total soluble solids contents, and FRAP (20%), TEAC (72%), and DPPH (62%) values. The honey mixed beverages exhibited a better phenolic compound profile with an increase in catechin contents and an enrichment of quercetin when compared to the control mixed beverage, as well presenting good sensory acceptance. In conclusion, our results show that the addition of honey can be an alternative for improving the nutritional and sensorial characteristics of an apple and passion fruit mixed beverage.

Phenolic composition and biological activities of stingless bee honey: An overview based on its aglycone and glycoside compounds

Stingless bees are native to tropical and subtropical countries, such as Brazil. The wide variety of species, the sources of food collection (nectar and pollen), and the climate conditions strongly affect the chemical composition of the honey, making this a unique product with peculiar characteristics. Stingless bee honey presents higher water content, higher acidity, and a lower sugar concentration when compared to Apis mellifera honey. Moreover, there is a wide variety of microorganisms in stingless bees' environment, which leads their honey to go through a natural fermentative process during its production in the hive. Besides, fermentation and hydrolysis are effective ways to convert glycosides into aglycones, thus increasing the bioavailability of compounds. In this sense, stingless bee honey may possess a greater concentration of phenolic compounds aglycones than glycosides, which would increase its potential benefits. Therefore, this review aims to compile the most recent studies of stingless bee honey phenolic profile and its biological potential (antioxidant, antimicrobial, and anti-inflammatory activities) and a possible connection to its natural fermentation process.

Physicochemical and Medicinal Properties of Tualang, Gelam and Kelulut Honeys: A Comprehensive Review

Tualang, Gelam and Kelulut honeys are tropical rainforest honeys reported to have various medicinal properties. Studies related to the medicinal properties and physicochemical characteristics of these honeys are growing extensively and receiving increased attention. This review incorporated and analysed the findings on the biological and physicochemical properties of these honeys. Tualang, Gelam and Kelulut honeys were found to possess a wide variety of biological effects attributed to their physicochemical characteristics. Findings revealed that these honeys have anti-diabetic, anti-obesity, anti-cancer, anti-oxidative, anti-microbial, anti-inflammatory and wound-healing properties and effects on the cardiovascular system, nervous system and reproductive system. The physicochemical properties of these honeys were compared and discussed and results showed that they have high-quality contents and excellent antioxidant sources.

The Inhibitory Effects of Heterotrigona Itama Honey Marinades on the Formation of Carcinogenic Heterocyclic Amines in Grilled Beef Satay

Heterocyclic amines (HCAs) are carcinogenic food toxicants formed in cooked meats, which may increase the risk of cancer development in humans. Therefore, in this study, the effect of stingless bee honey from different botanical origins on the formation of HCAs in grilled beef satay was investigated. HCAs concentration in grilled beef satay was determined by using high performance liquid chromatography (HPLC). In total, six of the most toxigenic HCAs representing aminoimidazo-azaarenes (AIAs) (MeIQx, 4,8-DiMeIQx, and PhIP) and amino carbolines (norharman, harman, and AαC) groups were identified in all the beef samples investigated. A significant reduction in HCAs was observed in grilled beef marinated in honey as compared to beef samples marinated in table sugar (control), in which the reduction of 95.14%, 88.45%, 85.65%, and 57.22% was observed in gelam, starfruit, acacia, and Apis honey marinades, respectively. According to the partial least squares regression (PLS) model, the inhibition of HCAs in grilled beef was shown to be significantly correlated to the antioxidant activity (IC50) of the honey samples. Therefore, the results of this study revealed that the addition of stingless bee honey could play an important role in reducing HCAs in grilled beef.