Phenolic acid composition and antioxidant properties of Malaysian honeys

Chemical Characterization and Biological Properties of Leguminous Honey

Honey can beneficially act against different human diseases, helping our body to improve its health. The aim of the present study was first to increase knowledge of some biochemical characteristics (amount and composition of polyphenols and volatile organic compounds, vitamin C content) of five Italian legume honeys (alfalfa, astragalus, carob, indigo, and sainfoin). Furthermore, we evaluated their potential health properties by studying their antioxidant and in vitro anti-inflammatory activities and in vitro inhibitory effects on three enzymes involved in neurodegenerative diseases (acetylcholinesterase, butyrylcholinesterase, and tyrosinase). Alfalfa honey showed the highest total polyphenol content (TPC) (408 μg g-1 of product). Indigo honey showed the lowest TPC (110 μg g-1 of product). The antioxidant activity was noteworthy, especially in the case of sainfoin honey (IC50 = 6.08 mg), which also exhibited excellent inhibitory action against butyrylcholinesterase (74%). Finally, the correlation between the biochemical and functional results allowed us to identify classes of molecules, or even single molecules, present in these five honeys, which are capable of influencing the properties indicated above.

Accelerated loss of diastase in mānuka honey: Investigation of mānuka specific compounds

Diastase is used internationally as a quality monitor for excessive heat treatment and prolonged storage of honey; honey must contain an activity of at least 8 diastase numbers (DN) for it to be considered export quality. Freshly harvested mānuka honey can have diastase activity close to the export threshold of 8 DN without excess heating, increasing susceptibility for export failure. This research investigated the effect of compounds unique to or high in concentration in mānuka honey on diastase activity. Investigation of the effect of methylglyoxal, dihydroxyacetone, 2-methoxybenzoic acid, 3-phenyllatic acid, 4-hydroxyphenyllactic acid and 2'-methoxyacetophenone on diastase activity was carried out. Mānuka honey was stored at 20 and 27 °C and clover honey spiked with compounds of interest were stored at 20, 27 and 34 °C and monitored overtime. Methylglyoxal and 3-phenyllactic acid were found to accelerate the loss of diastase above the loss normally observed with time and elevated temperature.

Role of bZIP transcription factors in the regulation of plant secondary metabolism

MAIN CONCLUSION

This study provides an overview of the structure, classification, regulatory mechanisms, and biological functions of the basic (region) leucine zipper transcription factors and their molecular mechanisms in flavonoid, terpenoid, alkaloid, phenolic acid, and lignin biosynthesis. Basic (region) leucine zippers (bZIPs) are evolutionarily conserved transcription factors (TFs) in eukaryotic organisms. The bZIP TFs are widely distributed in plants and play important roles in plant growth and development, photomorphogenesis, signal transduction, resistance to pathogenic microbes, biotic and abiotic stress, and secondary metabolism. Moreover, the expression of bZIP TFs not only promotes or inhibits the accumulation of secondary metabolites in medicinal plants, but also affects the stress response of plants to the external adverse environment. This paper describes the structure, classification, biological function, and regulatory mechanisms of bZIP TFs. In addition, the molecular mechanism of bZIP TFs regulating the biosynthesis of flavonoids, terpenoids, alkaloids, phenolic acids, and lignin are also elaborated. This review provides a summary for in-depth study of the molecular mechanism of bZIP TFs regulating the synthesis pathway of secondary metabolites and plant molecular breeding, which is of significance for the generation of beneficial secondary metabolites and the improvement of plant varieties.

Effects of Aerobic Dance Exercise and Honey Supplementation Followed by Their Subsequent Cessation on Bone Metabolism Markers and Antioxidant Status in Young Collegiate Females

Background

Regular physical activity and proper nutritional intake are crucial for bone health. However, it is unclear if this health benefit is maintained after the removal of these stimuli. This study investigated the combined effects of aerobic dance exercise and honey supplementation, followed by their subsequent cessation on bone metabolism markers and antioxidant status in females.

Methods

Forty-eight young female college students were assigned into four groups: i) 16S (16 weeks of sedentary activity); ii) 8E×8S (8 weeks of exercise followed by 8 weeks of sedentary activity); iii) 8H8S (8 weeks of honey supplementation followed by 8 weeks of sedentary activity) and iv) 8E×H8S (8 weeks of combined exercise and honey supplementation followed by 8 weeks of sedentary activity). Blood samples were collected from the participants prior to the intervention, at week 8 and at week 16 for the analysis of bone metabolism markers and antioxidant status.

Results

At the mid test, bone speed of sound (SOS) (P < 0.01), serum alkaline phosphatase (ALP) (P < 0.001) and serum osteocalcin (P < 0.01) were significantly higher in the 8E×H8S group as compared to 16S group. After 8 weeks of cessation of exercise and honey supplementation, bone SOS was also significantly higher (P < 0.001) in the 8E×H8S group as compared to 16S group. In addition, the serum total calcium (P < 0.001), serum ALP (P < 0.01), total antioxidant status (TAS) (P < 0.01) and glutathione (GSH) (P < 0.01) in the 8E×H8S group were significantly higher at the post-test as compared to their respective pre-test values.

Conclusion

These findings demonstrate that there was improved maintenance of the beneficial effects induced by 8 weeks of combined exercise and honey supplementation on bone properties and the antioxidant status after 8 weeks of cessation of exercise and honey supplementation as compared to exercise and honey supplementation alone.

Network Pharmacology and Molecular Docking Analysis of Active Compounds in Tualang Honey against Atherosclerosis

Atherosclerosis, a pathological condition marked by the accumulation of lipids and fibrous substances in the arterial walls, is a leading cause of heart failure and death. The present study aimed to utilize network pharmacology to assess the potential pharmacological effects of bioactive compounds in Tualang honey on atherosclerosis. This is significant as previous studies have indicated the cardioprotective effects of Tualang honey, yet a comprehensive evaluation using network pharmacology has yet to be conducted. The bioactive compounds in Tualang honey were screened and the potential gene targets for these compounds were predicted through Swiss Target Prediction and SuperPred databases. Atherosclerosis genes were retrieved from the OMIM, DisGeNet, and GeneCards databases. The interaction between these compounds and atherosclerosis genes was established through protein-protein interaction, gene ontology, and KEGG pathway analysis. The results of these analyses were then further confirmed through molecular docking studies using the AutoDock Tools software. The results revealed that 6 out of 103 compounds in Tualang honey met the screening criteria, with a total of 336 potential gene targets, 238 of which were shared with atherosclerosis. Further analysis showed that these active compounds had a good affinity with key targets and were associated with biological processes related to protein phosphorylation and inflammation as well as pathways related to lipid and atherosclerosis and other signaling pathways. In conclusion, the study provides insight into the potential pharmacological effects of Tualang honey bioactive compounds on atherosclerosis, supporting its use as a promising treatment for the disease.

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.

Honey on brain health: A promising brain booster

Since ancient times, honey has been employed in many aspects of everyday life, the most popular of which is as a natural sweetener. Honey is used not only as a nutritional product but also in health as a supplement and in various applications, especially related to brain booster health. Brain health is the capacity to carry out all mental functions necessary for cognition, such as learning and judging, utilizing language, and recalling. This review presents the current trend of research on honey, particularly the interest in underlying mechanisms related to brain booster health. A total of 34 original articles addressing brain health from the consumption of honey were analyzed. We identified four main brain health benefits, which are memory booster, neuroprotective effect, anti-stress, and anti-nociceptive potentials with the proposed underlying mechanism. A lot of attention has been paid to the role that honey plays in brain health research, with the goal of examining the link between honey and brain health as well as the mechanism underlying it, the findings from this review may be potentially beneficial to develop new therapeutic roles for honey to help determine the best and most promising to benefit and boost overall brain health.

Potential of Natural Honey in Controlling Obesity and its Related Complications

Honey has a long history of therapeutic properties for multiple diseases, including inflammation and oxidative stress. This review aimed to provide a better understanding and renewed interest in the potential role of honey in obesity control, obesity-related diseases treatment and weight management, with specific reference to its components and the effect of honey overall. There is compelling evidence that honey possesses the desired properties for this purpose, as seen in the in vitro, in silico, in vivo and clinical analyses discussed in this review. This review also highlights the components potentially responsible for the health benefits of honey. Honey and its components reduce blood sugar levels, improve insulin sensitivity and lipid metabolism by reducing triglycerides, and reduce total cholesterol and LDL levels while increasing HDL levels that prevent excessive weight gain and reduce the risk of obesity and its complications. Further controlled studies are necessary to validate the role of honey in the management of obesity, both as a preventive and as a therapeutic agent.

The Development and Application of a HPTLC-Derived Database for the Identification of Phenolics in Honey

This study reports on the development and validation of a HPTLC-derived database to identify phenolic compounds in honey. Two database sets are developed to contain the profiles of 107 standard compounds. Rich data in the form of Rf values, colour hues (H°) at 254 nm and 366 nm, at 366 nm after derivatising with natural product PEG reagent, and at 366 nm and white light after derivatising with vanillin–sulfuric acid reagent, λ max and λ min values in their fluorescence and λ max values in their UV-Vis spectra as well as λ max values in their fluorescence and UV-Vis spectra after derivatisation are used as filtering parameters to identify potential matches in a honey sample. A spectral overlay system is also developed to confirm these matches. The adopted filtering approach is used to validate the database application using positive and negative controls and also by comparing matches with those identified via HPLC-DAD. Manuka honey is used as the test honey and leptosperine, mandelic acid, kojic acid, lepteridine, gallic acid, epigallocatechin gallate, 2,3,4-trihydroxybenzoic acid, o-anisic acid and methyl syringate are identified in the honey using the HPTLC-derived database.

Natural Products in Mitigation of Bisphenol A Toxicity: Future Therapeutic Use

Bisphenol A (BPA) is a ubiquitous environmental toxin with deleterious endocrine-disrupting effects. It is widely used in producing epoxy resins, polycarbonate plastics, and polyvinyl chloride plastics. Human beings are regularly exposed to BPA through inhalation, ingestion, and topical absorption routes. The prevalence of BPA exposure has considerably increased over the past decades. Previous research studies have found a plethora of evidence of BPA’s harmful effects. Interestingly, even at a lower concentration, this industrial product was found to be harmful at cellular and tissue levels, affecting various body functions. A noble and possible treatment could be made plausible by using natural products (NPs). In this review, we highlight existing experimental evidence of NPs against BPA exposure-induced adverse effects, which involve the body’s reproductive, neurological, hepatic, renal, cardiovascular, and endocrine systems. The review also focuses on the targeted signaling pathways of NPs involved in BPA-induced toxicity. Although potential molecular mechanisms underlying BPA-induced toxicity have been investigated, there is currently no specific targeted treatment for BPA-induced toxicity. Hence, natural products could be considered for future therapeutic use against adverse and harmful effects of BPA exposure.

Pathophysiology of Depression: Stingless Bee Honey Promising as an Antidepressant

Depression is a debilitating psychiatric disorder impacting an individual’s quality of life. It is the most prevalent mental illness across all age categories, incurring huge socio-economic impacts. Most depression treatments currently focus on the elevation of neurotransmitters according to the monoamine hypothesis. Conventional treatments include tricyclic antidepressants (TCAs), norepinephrine–dopamine reuptake inhibitors (NDRIs), monoamine oxidase inhibitors (MAOIs), and serotonin reuptake inhibitors (SSRIs). Despite numerous pharmacological strategies utilising conventional drugs, the discovery of alternative medicines from natural products is a must for safer and beneficial brain supplement. About 30% of patients have been reported to show resistance to drug treatments coupled with functional impairment, poor quality of life, and suicidal ideation with a high relapse rate. Hence, there is an urgency for novel discoveries of safer and highly effective depression treatments. Stingless bee honey (SBH) has been proven to contain a high level of antioxidants compared to other types of honey. This is a comprehensive review of the potential use of SBH as a new candidate for antidepressants from the perspective of the monoamine, inflammatory and neurotrophin hypotheses.

STINGLESS BEE HONEY (Tetragonula laeviceps): CHEMICAL COMPOSITION AND THEIR POTENTIAL ROLES AS AN IMMUNOMODULATOR IN MALNOURISHED RATS

Honey is rich in bioactive compounds, phenolic acids, and flavonoids and is an antioxidant and an immunomodulator. The objectives of this study were to determine the honey chemical composition of Indonesian stingless bees and their potential roles as an immunomodulator in the malnourished rats. Tetragonula laeviceps honey was used to analyses of chemical composition was obtained from three different geographical origins were Depok Sleman, Bayan Lombok, and Nglipar Gunungkidul. Thirty-two rats were divided into four groups of 8 rats and placed in individual cages. The experimental designed was as follows: T1 = normal rats + without honey (0–7 weeks), T2 = normal rats + with honey of 1.8 g/kg BW/day (0–7 weeks), T3 = malnourished honey of 1.8 g/kg BW/day started from 2 weeks after the malnourished condition (2–7 weeks). The results showed that the chemical composition of Tetragonula laeviceps honey from three different geographical origins were vitamin C content (6.49–13.58 mg/100 g), total phenolic content (0.65–2.30% GAE/100 g), total flavonoid content (0.28–1.00 mg QE/g), and antioxidant activity DPPH (61.43–90.28%). The application of fresh honey from stingless bee that was offered to either normal or malnourished rats were increased lymphocytes proliferation and decreased the production of both proinflammatory markers, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) from tissue culture supernatant of lymphocytes (p < 0.01). Data from this study clearly indicates the potential role of honey from stingless bee as an immunomodulator in malnourished rats.

Honeys as Possible Sources of Cholinesterase Inhibitors

Alzheimer’s disease (AD) is a progressive neurodegenerative disease characterised by low levels of the neurotransmitter (acetylcholine), oxidative stress, and inflammation of the central nervous system. The only currently available form of treatment entails the administration of AChE/BChE (acetylcholinesterase/butyrylcholinesterase) inhibitors to patients diagnosed with the disease. However, AD prevention is possible by administering the correct inhibitors with food. The aim of this study was to examine 19 types of honey in terms of their contents of cholinesterase inhibitors. The inhibition of AChE and BChE relative to the respective honey samples was evaluated using Ellman’s colorimetric method, including the “false-positive” effect. The highest potential for AChE inhibition was observed in the case of thyme honey (21.17% inhibition), while goldenrod honey showed the highest capacity for BChE inhibition (33.89%). Our study showed that honeys may provide a rich source of cholinesterase inhibitors and, in this way, play a significant role in AD.

Role of Honey in Obesity Management: A Systematic Review

Obesity is a metabolic disorder that has become critically prevalent throughout the world. Obesity has been linked to other chronic diseases such as diabetes mellitus, cardiovascular diseases and cancer. Natural products such as honey have been investigated for their potential effect on obesity. Hence, this study systematically reviewed the recent literature concerning the effects of honey on obesity in obese animal models and in people with obesity. The Ovid MEDLINE, PubMed, Scopus, Web of Science and Google Scholar electronic databases were searched for relevant articles. A total of 130 relevant articles were obtained from the initial search. Following a thorough screening, nine articles were selected for data extraction, including six animal studies and three clinical trials. In most of the animal studies, honey demonstrated an anti-obesity effect by reducing body weight, body fat composition and adipocyte size, among others. However, supplementation of honey in clinical trials showed conflicting results. Even though honey supplementation did not demonstrate any weight-reducing effect in some of the clinical trials, none of the trials showed that honey increases body weight. However, the results should be interpreted with caution as most of the studies involved animal models and there is a limited number of high quality, randomized, controlled clinical trials.

Systematic Review Registration

https://inplasy.com/inplasy-2022-6-0038/ PROSPERO, identifier 10.37766/inplasy2022.6.0038.

A Comprehensive Survey of Phenolic Constituents Reported in Monofloral Honeys around the Globe

The aim of this review is to provide a comprehensive overview of the large variety of phenolic compounds that have to date been identified in a wide range of monofloral honeys found globally. The collated information is structured along several themes, including the botanical family and genus of the monofloral honeys for which phenolic constituents have been reported, the chemical classes the phenolic compounds can be attributed to, and the analytical method employed in compound determination as well as countries with a particular research focus on phenolic honey constituents. This review covers 130 research papers that detail the phenolic constituents of a total of 556 monofloral honeys. Based on the findings of this review, it can be concluded that most of these honeys belong to the Myrtaceae and Fabaceae families and that Robinia (Robinia pseudoacacia, Fabaceae), Manuka (Leptospermum scoparium, Myrtaceae), and Chestnut (Castanea sp., Fagaceae) honeys are to date the most studied honeys for phenolic compound determination. China, Italy, and Turkey are the major honey phenolic research hubs. To date, 161 individual phenolic compounds belonging to five major compound groups have been reported, with caffeic acid, gallic acid, ferulic acid and quercetin being the most widely reported among them. HPLC with photodiode array detection appears to be the most popular method for chemical structure identification.

Antioxidant Properties and Characterization of Heterotrigona itama Honey from Various Botanical Origins according to Their Polyphenol Compounds

Stingless bee honey is a good source of antioxidants, which is attributed to the phenolic compounds. The type and concentration of phenolic compounds in honey can be affected by botanical origin. Therefore, in this study, Heterotrigona itama honey from three botanical origins (gelam, acacia, and starfruit) was evaluated for its antioxidant activity and profile of phenolic compounds. Apis mellifera honey was used as a comparison. Antioxidant activity and profile of phenolic compounds in honey were determined using spectrophotometric and chromatographic methods, respectively. The total phenolic content (TPC), total flavonoids content (TFC), free radical scavenging activity (IC50), and ferric reducing antioxidant power (FRAP) of H. itama were ranged between 52.64 and 74.72 mg GAE/100 g honey, 10.70–25.71 mg QE/100 g honey, 11.27–24.09 mg/mL, and 77.88–164.88 µmol FeSO4.7H2O/100 g honey, respectively. The findings showed that the antioxidant activity and phenolic and flavonoid contents in H. itama honey were significantly higher than Apis honey. Benzoic acid and taxifolin were found as the predominant phenolic acid and flavonoid in all samples. However, chrysin was significantly highest in Apis honey than stingless bee honey. This result suggested that chrysin can be used as a chemical marker to distinguish Apis honey from stingless bee honey. Gallic acid and ellagic acid were found as the chemical marker for gelam honey, salicylic acid, benzoic acid, and 4-hydroxybenzoic acid for starfruit honey while ferulic acid for acacia honey.

Chemical Composition Analysis and Antioxidant Activity of Coffea robusta Monofloral Honeys from Vietnam

Monofloral honey samples (Coffea robusta) from Vietnam were determined for their chemical compositions. This is the first report on the chemical composition and antioxidant activity of coffee honey from Vietnam. These samples were characterized by their high contents of total and reducing sugars, total phenolic contents, and total flavonoid contents. The contents of seven phenolic acids (PAs) were quantified by high performance liquid chromatography (HPLC) and analyzed with the assistance of principle component analysis (PCA) to differentiate the honey samples into groups. The hydroxymethylfurfural (HMF) (0.048–2.933 mg/kg) and free acid contents (20.326–31.163 meq/kg) of coffee honey were lower in Nepal, which reflected the freshness of the honey when conducting this survey. The coffee honey had total sugar and reducing sugar contents 831.711 g/kg and 697.903 g/kg, respectively. The high level of total phenolic (0.642 mg GAE/g) and flavonoid (0.0341 mg GE/g) contents of coffee honey contributed to their antioxidant activity of this honey sample. Among the coffee honey tested, the IC₅₀ of DPPH radical-scavenging activities value was 1.134–17.031 mg/mL, while the IC₅₀ of ABTS radical-scavenging activities value was 115.381–213.769 mg/mL. The phenolic acids composition analysis displayed that gallic acid appeared in high concentrations in all studied honey samples, ranging from 0.037–1.015 mg/kg, and ferulic acid content ranged from 0.193 to 0.276 mg/kg. The content of trigonelline and caffeine in coffee honey samples ranged from 0.314–2.399 mg/kg and 8.946–37.977 mg/kg. The data in this article highlight the relevance of coffee honey as a healthy substance.

Bitter Gourd Honey Ameliorates Hepatic and Renal Diabetic Complications on Type 2 Diabetes Rat Models by Antioxidant, Anti-Inflammatory, and Anti-Apoptotic Mechanisms

Honey has several pharmacological effects, including anti-diabetic activity. However, the effectiveness of bitter gourd honey (BGH) in the treatment of diabetes mellitus (DM) is unknown. The aim of this study was to determine the antioxidant, anti-inflammatory, and anti-apoptotic properties of BGH on the kidney and liver of a streptozotocin-induced diabetes rat model.

METHODS

A single dose (nicotinamide 110 mg/kg, streptozotocin (STZ) 55 mg/kg, intraperitoneal (i.p.)) was used to induce DM in male rats. For 28 days, normal or diabetic rats were administered 1 g/kg/day and 2 g/kg/day of BGH orally. After the treatment, blood, liver, and kidney samples were collected and analysed for biochemical, histological, and molecular parameters. In addition, liquid chromatography-mass spectrometry (LC-MS) was used to identify the major bioactive components in BGH.

RESULTS

The administration of BGH to diabetic rats resulted in significant reductions in alanine transaminase (ALT),aspartate aminotransferase (AST), creatinine, and urea levels. Diabetic rats treated with BGH showed lesser pathophysiological alterations in the liver and kidney as compared to non-treated control rats. BGH-treated diabetic rats exhibited reduced levels of oxidative stress (MDA levels), inflammatory (MYD88, NFKB, p-NFKB, IKKβ), and apoptotic (caspase-3) markers, as well as higher levels of antioxidant enzymes (SOD, CAT, and GPx) in the liver and kidney. BGH contains many bioactive compounds that may have antioxidative stress, anti-inflammatory, and anti-apoptotic effects.

CONCLUSION

BGH protected the liver and kidney in diabetic rats by reducing oxidative stress, inflammation, and apoptosis-induced damage. As a result, BGH can be used as a potential therapy to ameliorate diabetic complications.

Tualang Honey: A Decade of Neurological Research

Tualang honey has been shown to protect against neurodegeneration, leading to improved memory/learning as well as mood. In addition, studies have also demonstrated its anti-inflammatory and antioxidant properties. However, a substantial part of this research lacks systematization, and there seems to be a tendency to start anew with every study. This review presents a decade of research on Tualang honey with a particular interest in the underlying mechanisms related to its effects on the central nervous system. A total of 28 original articles published between 2011 and 2020 addressing the central nervous system (CNS) effects of Tualang honey were analysed. We identified five main categories, namely nootropic, antinociceptive, stress-relieving, antidepressant, and anxiolytic effects of Tualang honey, and proposed the underlying mechanisms. The findings from this review may potentially be beneficial towards developing new therapeutic roles for Tualang honey and help in determining how best to benefit from this brain supplement.

Unifloral ajwain honey ameliorates differential inhibition of matrix metalloproteinases 2 and 9 protein, cytotoxicity, and antioxidant potential

BACKGROUND

Free radicals lead to inflammation, which in turn could intervene several chronic diseases including cancer. The promising scientific finding for anti-cancer properties of honey is an area of great interest.

OBJECTIVE

The present study was designed to investigate the invitro biological effects (cytotoxic, and anti-inflammatory through differential inhibition of metalloproteinases and antioxidant) of unifloral Ajwain honey along with its physicochemical properties (pH, moisture, ash content, electrical conductivity, color, protein).

MATERIALS AND METHODS

Three Ajwain honey samples (AJ-1, AJ-2, and AJ-3) were collected from different geographical origins of Western Ghats of India. Melissopalynological analysis was carried out to confirm uniflorality. Physicochemical analysis for ash, moisture content, pH, electrical conductivity, color, and total protein was estimated. Total polyphenol, total flavonoid content, and ferric reducing ability of plasma assay were determined using appropriate methods. The cytotoxic effect was assessed against breast cancer cells (MDA-MB-231) by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and the anti-inflammatory activity was evaluated by gelatin zymography of matrix metalloproteinases MMP-2 and MMP-9 proteins.

RESULTS

Melissopalynological analysis confirmed pollens from Ajwain plant's and so-called Ajwain honey. MTT assay depicted inhibitory trend for all honey samples across the concentrations (6.25-100 mg/ml) as compared to untreated cells. Gelatin zymography of metalloproteinases (MMP-2 and MMP-9) showed inhibitory tendency in all Ajwain honey samples. The AJ-3 honey sample had the highest inhibition at 0.625%. A significant correlation between honey color, pH, and protein content was perceived throughout the study.

CONCLUSION

This study highlights the invitro biological evidence for possible therapeutic application of Ajwain honey samples in cytotoxic, anti-inflammatory, and antioxidant management as well as can be considered a potent source of supplements in human nutrition.

The bioactive, antioxidant, antibacterial, and physicochemical properties of a range of commercially available Australian honeys

Honey is a supersaturated sugar solution produced from plant nectar, with its composition influenced by geographic and floral origins, and with several properties contributing to its health-related abilities. This study aimed to determine the bioactive composition, antioxidant characteristics, antibacterial activity, and physicochemical properties of commercial Australian honeys. In total, 42 commercial Australian honeys were selected, and categorised according to front-label descriptions. Honeys were analysed: quality (Hydroxymethylfurfural); colour (colour intensity, L*,a*,b*); bioactive composition (phenolic, flavonoid, and carotenoid content); antioxidant characteristics (DPPH, CUPRAC, FRAP); antibacterial activity (MIC50); physicochemical properties (pH, TSS, viscosity, a w). Colour intensity correlated with each assessed bioactive compound and antioxidant characteristic (p ≤ 0.001). MIC50 (S. aureus) was associated with FRAP and a w, suggesting mechanisms of action for honey's antibacterial activity. Manuka-type honeys had higher colour intensity (1440 (98.5) mAU) than other categories (p ≤ 0.05), and consistently higher bioactive and antioxidant properties. This provides the potential to inform antioxidant-related health outcomes.

Establishing Relationship between Vitamins, Total Phenolic and Total Flavonoid Content and Antioxidant Activities in Various Honey Types

Honey is a well-known natural sweetener and is rich in natural antioxidants that prevent the occurrence of oxidative stress, which is responsible for many human diseases. Some of the biochemical compounds in honey that contribute to this property are vitamins and phenolic compounds such as phenolic acids and flavonoids. However, the extent to which these molecules contribute towards the antioxidant capacity in vitro is inconsistently reported, especially with the different analytical methods used, as well as other extrinsic factors that influence these molecules' availability. Therefore, by reviewing recently published works correlating the vitamin, total phenolic, and flavonoid content in honey with its antioxidant activities in vitro, this paper will establish a relationship between these parameters. Based on the literature, vitamins do not contribute to honey's antioxidant capacity; however, the content of phenolic acids and flavonoids has an impact on honey's antioxidant activity.

Therapeutic Properties of Honey for the Management of Wounds; Is There a Role in the Armamentarium of Diabetic Foot Ulcer Treatment? Results From In vitro and In vivo Studies

Diabetic foot ulcers are one of the most dreadful complications of diabetes mellitus and efforts to accelerate diabetic wound healing are of paramount importance to prevent ulcer infections and subsequent lower-limb amputations. There are several treatment approaches for the management of diabetic foot ulcers and honey seems to be a safe and cost-effective therapeutic approach on top of standard of care. The aim of this review was to summarize the therapeutic properties of honey and the data regarding its possible favorable effects on diabetic wound healing. A literature search of articles from 1986 until April 2021 was performed using MEDLINE, EMBASE, and the Cochrane Library to assess for studies examining the therapeutic wound healing properties of honey, it's in vitro effect, and the efficacy and/or mechanism of action of several types of honey used for the treatment of diabetic animal wounds. Honey has antioxidant, anti-inflammatory, and antibacterial properties and in vitro studies of keratinocytes and fibroblasts, as well as studies in diabetic animal models show that treatment with honey is associated with increased re-epithelialization and collagen production, higher wound contraction, and faster wound healing. The use of honey could be a promising approach for the management of diabetic foot ulcers.

Multidimensional Comparative Analysis of Bioactive Phenolic Compounds of Honeys of Various Origin

Honey is a natural product which owes its health benefits to its numerous bioactive compounds. The composition of honey is highly diverse and depends on the type of honey and its origin. Antioxidant capacity arises mainly from the total content of polyphenols and their composition. The aim of this study was to perform a multidimensional comparative analysis of phenolic compounds of honeys of various origins. Honeydew, buckwheat, manuka, Malaysian and goldenrod honeys had the highest antioxidant capacity (above 400 mg Trolox equivalents kg⁻¹). These honeys were also characterized by the highest total polyphenol content (about 2500 mg gallic acid equivalents (GAE) kg⁻¹) and the highest total flavonoid content (1400–1800 mg catechin equivalents (CAE) kg⁻¹). Other honeys had much lower antioxidant properties. A multidimensional analysis of the profiles of phenolic compounds showed that honeys constitute a non-homogeneous data set and manuka honey was in contrast to other samples. Principal component analysis (PCA) (based on 18 phenolic compounds) distinguished honeys into five groups. Manuka, Malaysian and honeydew honeys created their own separate groups and the location of other honeys was variable. Ultra-high-performance liquid chromatography (UHPLC) analysis demonstrated that profiles of polyphenols in honeys were highly varied. Caffeic acid, datiscetin and rhamnetin were characteristic compounds for manuka honey. Quercetin, kaempferol and apigenin were present in all honeys except Malaysian honey. The antioxidant properties and the profiles of bioactive phenolic compounds of honeys were miscellaneous. The richest sources of polyphenols were local buckwheat and honeydew honeys, alongside exotic manuka and Malaysian honeys. These honeys could provide valuable ingredients to the human diet, helping to prevent diseases.

Chemical composition and antioxidant content of Thymus vulgaris honey and Origanum vulgare essential oil; their effect on carbon tetrachloride-induced toxicity

Aim

The study investigated the chemical composition, antioxidant content, and antioxidant activity of Thymus vulgaris honey (TVH) and Origanum vulgare essential oil (OVEO) and their mixture effect on carbon tetrachloride (CCl₄)-induced toxicity.

Materials and Methods

The study conducted physicochemical characterization and chemical analysis of TVH and OVEO with the use of gas chromatography-mass spectrometry and high-performance liquid chromatograph (HPLC). The antioxidant activity of TVH and OVEO was done with the use of 1,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. The study used nine groups of rats to investigate the effect of TVH, OVEO, and a mixture of TVH and OVEO (HEM) on CCl₄-induced toxicity. Intraperitoneal injection of CCl₄ (1 mL/100 g) was used to induce toxicity. The doses of TVH and OVEO were 1 mg/kg.b.wt, and 50 mg/kg.b.wt, respectively. HEM contains TVH (1 mg/kg.b.wt) and OVEO (50 mg/kg.b.wt).

Results

TVH has a high content of phenols, flavonoids, and flavanols. HPLC analysis showed that TVH contains, for the 1^st time, epicatechin gallate, and at a high concentration. OVEO includes a high percentage of carvacrol and thymol. With the use of DPPH, OVEO was more potent than TVH. CCl₄ caused significant liver and kidney damage and lipid disorders, which were alleviated by HVT, OVEO, and HEM. HVT was more potent than OVEO (p<0.05), and HEM was more potent than HVT and OVEO (p<0.05).

Conclusion

The study identified high content of epicatechin gallate for the 1^st time in TVH, and OVEO contains a high percentage of thymol and carvacrol. Epicatechin gallate might be useful as a marker for TVH. Mixing OVEO and TVH significantly potentiated their protection against CCl₄-induced liver and kidney toxicity.

The Potential use of Honey as a Remedy for Allergic Diseases: A Mini Review

Honey has been conventionally consumed as food. However, its therapeutic properties have also gained much attention due to its application as a traditional medicine. Therapeutic properties of honey such as anti-microbial, anti-inflammatory, anti-cancer and wound healing have been widely reported. A number of interesting studies have reported the potential use of honey in the management of allergic diseases. Allergic diseases including anaphylaxis, asthma and atopic dermatitis (AD) are threatening around 20% of the world population. Although allergic reactions are somehow controllable with different drugs such as antihistamines, corticosteroids and mast cell stabilizers, modern dietary changes linked with allergic diseases have prompted studies to assess the preventive and therapeutic merits of dietary nutrients including honey. Many scientific evidences have shown that honey is able to relieve the pathological status and regulate the recruitment of inflammatory cells in cellular and animal models of allergic diseases. Clinically, a few studies demonstrated alleviation of allergic symptoms in patients after application or consumption of honey. Therefore, the objective of this mini review is to discuss the effectiveness of honey as a treatment or preventive approach for various allergic diseases. This mini review will provide insights into the potential use of honey in the management of allergic diseases in clinical settings.

Antibiofilm Activity of Heather and Manuka Honeys and Antivirulence Potential of Some of Their Constituents on the DsbA1 Enzyme of Pseudomonas aeruginosa

Heather honey was tested for its effect on the formation of biofilms by Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Enterococcus faecalis, Salmonella Enteriditis and Acinetobacter baumanii in comparison with Manuka honey. At 0.25 mg/mL, Heather honey inhibited biofilm formation in S. aureus, A. baumanii, E. coli, S. Enteriditis and P. aeruginosa, but promoted the growth of E. faecalis and K. pneumoniae biofilms. Manuka honey inhibited biofilm formation in K. pneumoniae, E. faecalis, and S. Enteriditis, A. baumanii, E. coli and P. aeruginosa, but promoted S. aureus biofilm formation. Molecular docking with Autodock Vina was performed to calculate the predictive binding affinities and ligand efficiencies of Manuka and Heather honey constituents for PaDsbA1, the main enzyme controlling the correct folding of virulence proteins in Pseudomonas aeruginosa. A number of constituents, including benzoic acid and methylglyoxal, present in Heather and/or Manuka honey, revealed high ligand efficiencies for the target enzyme. This helps support, to some extent, the decrease in P. aeruginosa biofilm formation observed for such honeys.

A Review on Oxidative Stress, Diabetic Complications, and the Roles of Honey Polyphenols

Despite the availability of various antidiabetic drugs, diabetes mellitus (DM) remains one of the world's most prevalent chronic diseases and is a global burden. Hyperglycaemia, a characteristic of type 2 diabetes mellitus (T2DM), substantially leads to the generation of reactive oxygen species (ROS), triggering oxidative stress as well as numerous cellular and molecular modifications such as mitochondrial dysfunction affecting normal physiological functions in the body. In mitochondrial-mediated processes, oxidative pathways play an important role, although the responsible molecular mechanisms remain unclear. The impaired mitochondrial function is evidenced by insulin insensitivity in various cell types. In addition, the roles of master antioxidant pathway nuclear factor erythroid 2-related factor 2 (Nrf2)/Kelch-like ECH-associated protein 1 (Keap1)/antioxidant response elements (ARE) are being deciphered to explain various molecular pathways involved in diabetes. Dietary factors are known to influence diabetes, and many natural dietary factors have been studied to improve diabetes. Honey is primarily rich in carbohydrates and is also abundant in flavonoids and phenolic acids; thus, it is a promising therapeutic antioxidant for various disorders. Various research has indicated that honey has strong wound-healing properties and has antibacterial, anti-inflammatory, antifungal, and antiviral effects; thus, it is a promising antidiabetic agent. The potential antidiabetic mechanisms of honey were proposed based on its major constituents. This review focuses on the various prospects of using honey as an antidiabetic agent and the potential insights.

Biofilm Formation Reducing Properties of Manuka Honey and Propolis in Proteus mirabilis Rods Isolated from Chronic Wounds

Chronic wound infections are difficult to manage because of the biofilm formation in the wound environment. New measures for eliminating infections are necessary to increase the chance of wound healing. Apitherapy may be the new solution. The aim of this study was to assess the prevalence of wound infection factors and to examine the impact of Manuka honey and ethanol extract of propolis on biofilm formation of Proteus mirabilis isolated from chronic wound infections. According to the findings, the most frequent factors of infection are Staphylococcus aureus (46.1%), Pseudomonas aeruginosa (35.0%), and Proteus mirabilis (10.6%). Minimal inhibitory concentration and minimal bactericidal concentration values were assigned using the microbroth dilution test according to the Clinical and Laboratory Standards Institute. Biofilm of Proteus mirabilis isolates was formed in 96-well polystyrene plates and treated with Manuka honey (concentrations from 1.88% to 30.0%) and ethanol extract of propolis (1.0% to 40.0%). After 24 h, the biofilm viability was expressed by formazan absorbance (λ = 470 nm). Manuka honey reduced the biofilm viability in all, and ethanol extract of propolis in most, of the concentrations tested. Ethanol extract of propolis at the concentrations of 20.0% and 40.0%, reduced biofilm viability stronger than ethanol itself. With these results comes the conclusion that these substances can reduce biofilm formation.

Tualang Honey Ameliorates Hypoxia-induced Memory Deficits by Reducing Neuronal Damage in the Hippocampus of Adult Male Sprague Dawley Rats

Objectives

A growing body of evidence indicates that hypoxia exposure causes learning and memory deficits. An effective natural therapeutic approach has, however, not been explored widely. Our previous studies found that Tualang honey administration protected learning and memory functions in ovariectomized rats. Therefore, the present study investigated its efficacy in ameliorating hypoxia-induced memory deficits in adult male Sprague Dawley rats.

Materials and Methods

The rats were divided into four groups: i) Normoxia treated with sucrose (n=12), ii) Normoxia treated with Tualang honey (n=12), iii) Hypoxia treated with sucrose (n=12), and iv) Hypoxia treated with Tualang honey (n=12). Tualang honey (0.2 g/kg/BW) and sucrose (1 mL of 7.9%) supplementations were administered orally to the rats daily for 14 days. Then the hypoxia groups were exposed to hypoxia (~11%) for 7 days, while the normoxia groups were kept in normal conditions. Following exposure to hypoxia, the rats' memories were analyzed using a novel object recognition task and T-maze test.

Results

The data revealed that rats exposed to hypoxia showed significant impairment in short-term memory (STM), spatial memory (p<0.01), and long-term memory (LTM) when compared to the normoxia group. Hypoxia rats treated with Tualang honey showed significant improvement in STM, LTM, and spatial memory (p<0.05) compared with those treated with sucrose (p<0.05). Tualang honey also reduced neuronal damage in the hippocampus of adult male Sprague Dawley rats exposed to hypoxia.

Conclusion

It is suggested that Tualang honey pretreatment has protective effects against hypoxia-induced memory deficits, possibly through its antioxidant contents.

Hepatoprotective Effects of a Novel Trihoney against Nonalcoholic Fatty Liver Disease: A Comparative Study with Atorvastatin

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disorder worldwide with no curative therapy. The aim of this study was to investigate the hepatoprotective effects of a novel Trihoney against biochemical and histological manifestations of NAFLD in hypercholesterolemic rabbits. Methodology. Forty-eight male New Zealand white (NZW) rabbits were grouped into normal diet (C), normal diet with 0.6 g/kg/day of Trihoney (C + H), 1% cholesterol diet (HCD), 1% cholesterol diet with 0.3 g/kg/day of Trihoney (HCD + H₁), 1% cholesterol diet with 0.6 g/kg/day of Trihoney (HCD + H₂), and 1% cholesterol diet with 2 mg/kg/day of atorvastatin (HCD + At.). Animals were sacrificed after 12 weeks of treatment. Serum lipids and liver function test (LFT) were measured prior to and at the endpoint of the experiment for total cholesterol (TC), low-density lipoprotein (LDL-c), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), and total bilirubin (T. Bil.). Liver was processed for histopathology study. Liver homogenate was analysed for oxidative stress parameters: superoxide dismutase (SOD), glutathione peroxidase (GPx), and malondialdehyde (MDA). Results. Lipid analysis approved the induction of hypercholesterolemia. A significant elevation (p < 0.01) of serum AST and ALT levels showed by the HCD group was compared to C and C + H groups. Trihoney exhibited a significant reduction (p < 0.001) of AST and ALT compared to the HCD group. Likewise, AST and ALT reduced significantly in the HCD + At. group (p < 0.001). Trihoney supplementation induced significant (p < 0.05) enhancement of SOD and GPx activities. Atorvastatin treatment was associated with significant (p < 0.05) reduction of SOD and GPx activities in the liver. Trihoney and atorvastatin showed marked (p < 0.001) reduction of hepatic lipid peroxidation. Trihoney showed histological protection against progression of NAFLD to nonalcoholic steatohepatitis (NASH). Atorvastatin exhibited no beneficial impact on hepatic architecture. Conclusion. Trihoney was able to maintain normal liver function and showed hepatoprotection against progression of NAFLD to NASH probably through hypocholesterolaemic and antioxidant functions.

Role of Antioxidants in Alleviating Bisphenol A Toxicity

Bisphenol A (BPA) is an oestrogenic endocrine disruptor widely used in the production of certain plastics, e.g., polycarbonate, hard and clear plastics, and epoxy resins that act as protective coating for food and beverage cans. Human exposure to this chemical is thought to be ubiquitous. BPA alters endocrine function, thereby causing many diseases in human and animals. In the last few decades, studies exploring the mechanism of BPA activity revealed a direct link between BPA-induced oxidative stress and disease pathogenesis. Antioxidants, reducing agents that prevent cellular oxidation reactions, can protect BPA toxicity. Although the important role of antioxidants in minimizing BPA stress has been demonstrated in many studies, a clear consensus on the associated mechanisms is needed, as well as the directives on their efficacy and safety. Herein, considering the distinct biochemical properties of BPA and antioxidants, we provide a framework for understanding how antioxidants alleviate BPA-associated stress. We summarize the current knowledge on the biological function of enzymatic and non-enzymatic antioxidants, and discuss their practical potential as BPA-detoxifying agents.

Protective effect of Tualang honey against cadmium-induced morphological abnormalities and oxidative stress in the ovary of rats

BACKGROUND

To investigate the protective effects of Tualang honey against the toxicity effects induced by cadmium (Cd) on the ovary.

METHODS

A total of 32 female Sprague Dawley rats were taken and randomly divided into four groups (n = 8). Throughout the experimental period of 6 weeks, negative control-NC (vehicle deionized water), positive control-CD (Cd at 5 mg/kg), Tualang honey followed by Cd exposure-TH (Tualang honey at 200 mg/kg and Cd at 5 mg/kg) and Tualang honey control-THC (Tualang honey at 200 mg/kg) groups, were administered orally on a daily basis.

RESULTS

Rats exposed to Cd were significantly higher in ovarian weight, number of antral and atretic follicles as compared to the NC group. The disruptive effects of Cd on ovarian follicles were associated with a disruption in gonadotropin hormones and decreases in follicular stimulating hormone (FSH) and luteinizing hormone (LH). Moreover, a significant formation of oxidative stress in ovarian Cd-exposed rats has been proven by increasing the level of lipid peroxidation products (malondialdehyde) and decreasing the levels of enzymatic antioxidant (catalase). Interestingly, a daily supplementation of high antioxidant agents such as Tualang honey in these animals, caused significant improvements in the histological changes. Additionally, less atretic follicles were observed, restoring the normal level of LH and FSH (P < 0.001), and normalizing the ovarian malondialdehyde (P < 0.05) and catalase levels in comparison with CD group (P < 0.05).

CONCLUSIONS

Tualang honey has protective effects against Cd-induced ovarian toxicity by reducing morphological abnormalities, restoring the normal levels of gonadotropin hormones and stabilizing equilibrium levels of lipid peroxidation and antioxidant enzyme in ovaries of rats.

Tualang honey supplementation as cognitive enhancer in patients with schizophrenia

Introduction

Schizophrenia is a chronic mental illness with clusters of symptoms, including cognitive impairment. This study aimed to explore the effect of Tualang Honey (TH) on cognitive domains, especially as it pertained to the verbal memory of schizophrenia patients.

Method

This was a cross-sectional study involved 80 individuals, diagnosed with schizophrenia. The Malay Version Auditory Verbal Learning Test (MVAVLT) was used. Data were analysed using SPSS 20.0 software. Intention to treat analysis was applied.

Result

A comparison of the total learning score at eight weeks between the two groups based on time effect and time-treatment interaction favoured TH group.

Conclusion

This study concludes that by supplementing schizophrenia patients with 8-week of TH did improve total learning performance across domains in the immediate memory among patients with schizophrenia.

Tualang Honey and its Methanolic Fraction Improve LPS-induced Learning and Memory Impairment in Male Rats: Comparison with Memantine

Background:

Tualang honey (TH) has been shown to exert beneficial effects on learning and memory function in various animal models. However, its learning and memory effects in lipopolysaccharide (LPS) rat model have not been elucidated.

Objective:

The present study aimed to investigate the cognitive-enhancing effects of TH and its methanolic fraction in comparison to the clinically approved N-methyl-D-aspartate (NMDA) receptor antagonist (memantine) using LPS rat model.

Methods:

A total of ninety male Sprague Dawley rats were divided into 5 groups: (i) control, (ii) untreated LPS (iii) LPS treated with 200 mg/kg TH, (iv) LPS treated with 150 mg/kg methanol fraction of TH (MTH) and (v) LPS treated with 10 mg/kg memantine. All treatments were administered intraperitoneally once daily for 14 days. Morris water maze (MWM) and novel object recognition (NOR) tests were performed to assess spatial and recognition memory function.

Results:

The present study confirmed that LPS significantly impairs spatial and recognition memory and alone treatment with TH or MTH improved spatial and recognition memory comparable to memantine.

Conclusion:

Both TH and its methanolic fraction improved spatial and recognition memory of LPS rat model comparable to memantine. Thus, TH and its methanolic fraction have potential preventivetherapeutic effects for neurodegenerative diseases involving neuroinflammation.

Honey and obesity-related dysfunctions: a summary on health benefits

Honey is a natural product, containing flavonoids and phenolic acids, appreciated for its therapeutic abilities since ancient times. Although the bioactive potential is linked to the composition, that is variable depending on mainly the botanical origin, honey has antioxidant and anti-inflammatory properties. Therefore, honey, administered alone or in combination with conventional therapy, might result useful in the management of chronic diseases that are commonly associated with oxidative stress and inflammation state. Obesity is a metabolic disorder characterized by visceral adiposity. The adipose tissue becomes hypertrophic and undergoes hyperplasia, resulting in a hypoxic environment, oxidative stress and production of pro-inflammatory mediators that can be responsible for other disorders, such as metabolic syndrome and neurodegeneration. Experimental evidence from animals have shown that honey improves glycemic control and lipid profile with consequent protection from endothelial dysfunction and neurodegeneration. The purpose of the present review is to summarize the current literature concerning the beneficial effects of honey in the management of the obesity-related dysfunctions, including neurodegeneration. Based on the key constituents of honey, the paper also highlights polyphenols to be potentially responsible for the health benefits of honey. Further well-designed and controlled studies are necessary to validate these benefits in humans.

Chemopreventive activity of Tualang honey against oral squamous cell carcinoma-in vivo

OBJECTIVE

The aim of this study was to evaluate the chemopreventive activity of Malaysian jungle Tualang honey (TH) after oral carcinogenesis induced with 4-nitroquinoline 1-oxide (4 NQO).

STUDY DESIGN

A total of 28 male Sprague-Dawley (SD) rats were distributed into 4 groups as follows: group 1 (nontreated group); group 2 (control), which received 4 NQO during 8 weeks in drinking water only; and groups 3 and 4, which received 4 NQO for 8 weeks in drinking water and treated with TH 1000 mg/kg and 2000 mg/kg by oral gavage for 10 weeks. All rats from all experiments were sacrificed after 22 weeks, and the incidence of oral neoplasms and histopathologic changes were microscopically evaluated. Moreover, immunohistochemical expression was analyzed in tongue specimens by using image analysis software. The expression of particular genes associated with oral cancer were assessed by using RT² Profiler PCR Array (Qiagen, Germantown, MD).

RESULTS

TH significantly reduced the incidence of oral squamous cell carcinoma (OSCC) and suppressed cancer cell proliferation via diminishing the expression of CCND1, EGFR, and COX-2. Furthermore, TH preserved cellular adhesion (epithelial polarity) through overexpression of β-catenin and e-cadherin and inhibited the OSCC aggressiveness by downregulating TWIST1 and RAC1.

CONCLUSIONS

Our data suggest that TH exerts chemopreventive activity in an animal model in which oral cancer was induced by using 4 NQO.

HPLC Analysis of Phenolic Compounds and Flavonoids with Overlapping Peaks

The identification and quantification of phenolic compounds and flavonoids in various natural food products is typically conducted using HPLC analysis. Their analysis is particularly complex since most natural food products contain a large number of different phenolic compounds, many of which have similar chemical characteristics such as polarity, which makes complete separation of all eluents extremely difficult. In this work we present and validate a method for the quantitative determination of the concentration of two compounds with similar retention times, i.e. they show overlapping peaks in a mixed solution. Two pairs of phenolic compounds were investigated: caffeic and vanillic acids and ferulic and p-coumaric acids. This technique takes advantage of the different absorbances of the two phenolic compounds in the eluent at various wavelengths and can be used for the quantitative determination of the concentration of these compounds even if they are not separated in the HPLC column. The presented method could be used to interpret the results of HPLC analysis of food products which possess a vast spectrum of phenolic compounds and flavonoids.

Natural Products and Their Bioactive Compounds: Neuroprotective Potentials against Neurodegenerative Diseases

In recent years, natural products, which originate from plants, animals, and fungi, together with their bioactive compounds have been intensively explored and studied for their therapeutic potentials for various diseases such as cardiovascular, diabetes, hypertension, reproductive, cancer, and neurodegenerative diseases. Neurodegenerative diseases, including Alzheimer's disease, Huntington's disease, Parkinson's disease, and amyotrophic lateral sclerosis are characterized by the progressive dysfunction and loss of neuronal structure and function that resulted in the neuronal cell death. Since the multifactorial pathological mechanisms are associated with neurodegeneration, targeting multiple mechanisms of actions and neuroprotection approach, which involves preventing cell death and restoring the function to damaged neurons, could be promising strategies for the prevention and therapeutic of neurodegenerative diseases. Natural products have emerged as potential neuroprotective agents for the treatment of neurodegenerative diseases. This review focused on the therapeutic potential of natural products and their bioactive compounds to exert a neuroprotective effect on the pathologies of neurodegenerative diseases.

Honey and Its Phenolic Compounds as an Effective Natural Medicine for Cardiovascular Diseases in Humans?

Honey is a sweet, viscous syrup produced by the honey bee (Apis mellifera). It is probably the first natural sweetener ever discovered, and is currently used as a nutritious food supplement and medicinal agent. The aim of the present mini-review is to summarize and update the current knowledge regarding the role of honey in CVDs based on various experimental models. It also describes the role of its phenolic compounds in treating CVDs. Many such phenolic and flavonoid compounds, including quercetin, kaempferol, apigenin, and caffeic acid, have antioxidant and anti-platelet potential, and hence may ameliorate cardiovascular diseases (CVDs) through various mechanisms, such as by decreasing oxidative stress and inhibiting blood platelet activation. However, as the phenolic content of a particular type of honey is not always known, it can be difficult to determine whether any observed effects on the human cardiovascular system may be associated with the consumption of honey or its constituents. Therefore, further experiments in this area are needed.

Antioxidant properties and antimicrobial activity of manuka honey versus Polish honeys

Originating from New Zealand manuka honey distinguishes itself from other honeys. The purpose of this study was to compare the antioxidant and antimicrobial properties of manuka honey and selected Polish honeys. Antioxidant capacity, total polyphenol and total flavonoid content were determined. Furthermore, the antimicrobial activity and the Minimum Inhibitory Concentration (MIC) were evaluated. Obtained results demonstrated that manuka honeys possessed relatively high antioxidant capacity compared to the other, Polish honeys. It was only honeydew honey that achieved comparable antioxidant properties to manuka honeys. The findings were supported by the results of microbial assays. Manuka MGO-250 and MGO-400, alongside honeydew honey, showed a stronger antimicrobial effect against Gram(+) than against Gram(-) bacteria. Moreover, the MIC-values, expressed as an inhibin number, proved the high antibiotic activity of manuka honey against the strains of Staphylococcus aureus and Enterococcus faecalis. Research concerning the influence of manuka honey on human health should be continued.