Manuka honey: an emerging natural food with medicinal use

TLC-Bioautography-Guided Isolation and Assessment of Antibacterial Compounds from Manuka (Leptospermum scoparium) Leaf and Branch Extracts

A rapid procedure for the targeted isolation of antibacterial compounds from Manuka (Leptospermum scoparium) leaf and branch extracts was described in this paper. Antibacterial compounds from three different Manuka samples collected from New Zealand and China were compared. The active compounds were targeted by TLC-bioautography against S. aureus and were identified by HR-ESI-MS, and -MS/MS analysis in conjunction with Compound Discoverer 3.3. The major antibacterial component, grandiflorone, was identified, along with 20 β-triketones, flavonoids, and phloroglucinol derivatives. To verify the software identification, grandiflorone underwent purification via column chromatography, and its structure was elucidated through NMR analysis, ultimately confirming its identity as grandiflorone. This study successfully demonstrated that the leaves and branches remaining after Manuka essential oil distillation serve as excellent source for extracting grandiflorone. Additionally, we proposed an improved TLC-bioautography protocol for evaluating the antibacterial efficacy on solid surfaces, which is suitable for both S. aureus and E. coli. The minimum effective dose (MED) of grandiflorone was observed to be 0.29-0.59 μg/cm2 against S. aureus and 2.34-4.68 μg/cm2 against E. coli, respectively. Furthermore, the synthetic plant growth retardant, paclobutrazol, was isolated from the samples obtained in China. It is hypothesized that this compound may disrupt the synthesis pathway of triketones, consequently diminishing the antibacterial efficacy of Chinese Manuka extract in comparison to that of New Zealand.

First-Intention Incisional Wound Healing in Dogs and Cats: A Controlled Trial of Dermapliq and Manuka Honey

This study aimed to compare incisional wound healing in cats and dogs after the topical application of Μanuka honey and a new medical device, Dermapliq. Comparisons were made between each treatment and control, between the two treatments, and between dogs and cats. Twelve cats and twelve dogs were included in this study, and the impact of the two substances was examined through cosmetic, clinical, ultrasonographical, and histological evaluation. The use of Dermapliq in first-intention wound healing achieved a significantly better cosmetic evaluation score and better total clinical score at days 20-41, compared to the control, in both dogs and cats. The ultrasonographically estimated wound area was smaller with Dermapliq compared to the control. Wounds treated with Dermapliq showed histologically less inflammation compared to the control. The use of Manuka honey did not show a significantly better cosmetic score compared to the control. Skin thickening was significantly higher after using Manuka honey compared to the control and so was the total clinical score. However, the median wound area, as was evaluated ultrasonographically, was significantly smaller when wounds were treated with Manuka honey, the difference being more apparent in dogs. Dermapliq was proven to be a better choice in achieving favorable wound healing than Manuka honey in dogs and cats in first-intention healing. In our study, cats had a statistically better cosmetic score and less skin thickening and scar width compared to dogs. Histologically, cats showed significantly less edema, higher inflammation and angiogenesis scores, and lower fibroblast and epidermis thickening scores when compared to dogs.

Quality of Commercially Available Manuka Honey Expressed by Pollen Composition, Diastase Activity, and Hydroxymethylfurfural Content

Manuka honey plays a significant role in modern medical applications as an antibacterial, antiviral, and antibiotic agent. However, although the importance of manuka honey is well documented in the literature, information regarding its physicochemical characteristics remains limited. Moreover, so far, only a few papers address this issue in conjunction with the examination of the pollen composition of manuka honey samples. Therefore, in this study, two parameters crucial for honey quality control-the diastase number (DN) and the hydroxymethylfurfural (HMF) content-as well as the melissopalynological analysis of manuka honey, were examined. The research found a large variation in the percentage of Leptospermum scoparium pollen in honeys labeled and sold as manuka honeys. Furthermore, a significant proportion of these honeys was characterized by a low DN. However, since low diastase activity was not associated with low HMF content, manuka honey should not be considered as a honey with naturally low enzymatic activity. Overall, the DN and HMF content results indicate that the quality of commercially available manuka honey is questionable.

Anti-Glucotoxicity Effect of Phytoconstituents via Inhibiting MGO-AGEs Formation and Breaking MGO-AGEs

The therapeutic benefits of phytochemicals in the treatment of various illnesses and disorders are well documented. They show significant promise for the discovery and creation of novel medications for treating a variety of human diseases. Numerous phytoconstituents have shown antibiotic, antioxidant, and wound-healing effects in the conventional system. Traditional medicines based on alkaloids, phenolics, tannins, saponins, terpenes, steroids, flavonoids, glycosides, and phytosterols have been in use for a long time and are crucial as alternative treatments. These phytochemical elements are crucial for scavenging free radicals, capturing reactive carbonyl species, changing protein glycation sites, inactivating carbohydrate hydrolases, fighting pathological conditions, and accelerating the healing of wounds. In this review, 221 research papers have been reviewed. This research sought to provide an update on the types and methods of formation of methylglyoxal-advanced glycation end products (MGO-AGEs) and molecular pathways induced by AGEs during the progression of the chronic complications of diabetes and associated diseases as well as to discuss the role of phytoconstituents in MGO scavenging and AGEs breaking. The development and commercialization of functional foods using these natural compounds can provide potential health benefits.

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.

Cytoprotective Antioxidant, Anti-Inflammatory, and Antifibrotic Impact of Celery Seed Oil and Manuka Honey Against Cyclophosphamide-Induced Cystitis in Rabbits

Patients treated with cyclophosphamide (CP) usually suffer from severe hemorrhagic cystitis (HC). Our previous study exhibited that mesna + celery cotherapy partially ameliorated HC. Therefore, there is a substantial need to seek alternative regimens to get complete protection against CP-induced HC. The current study investigated the effects of mesna + celery seed oil (MCSO) or mesna + manuka honey (MMH) cotherapy against CP-induced HC in adult male rabbits. The forty rabbits were divided into four equal groups and treated for three weeks. The control group (G1) received distilled water and the second group (G2) received CP (50 mg/kg/week). The third group (G3) received CP + MCSO (CPMCSO regimen), and the fourth group (G4) received CP + MMH (CPMMH regimen). The urinary bladder (UB) specimens were processed to evaluate UB changes through histopathological, immunohistochemical, ultrastructural, and biochemical investigations. In G2, CP provoked HC features (urothelial necrosis, ulceration, and sloughing), UB fibrosis, and TNF-α immunoexpression. Besides, CP reduced the activity of antioxidant enzymes (GPx1, SOD3, and CAT) and elevated the serum levels of NF-κB, TNF-α, IL-1B, and IL-6 cytokines in G2 rabbits. In contrast, the CPMMH regimen caused significant increments of UB protection against HC in G4 rabbits compared to the partial protection by the CPMCSO regimen in G3. Therefore, our study indicated for the first time that the novel CPMMH regimen resulted in complete UB protection against CP-induced HC via combined antioxidant, anti-inflammatory, and antifibrotic properties.

Traces of Honeybees, Api-Tourism and Beekeeping: From Past to Present

Throughout history, honey has been used for many different purposes and due to its medicinal properties, has been one of the products marketed by traders. The figure of the bee first appeared in drawings on rock with the history of humanity, then on statues, as a logo, on money or stamps, and also in movies. Beekeeping museums, which present the historical process of beekeeping, also reflect an important culture with their ancient hives, documents, beekeeping materials, and historical antiquities. The contribution of bees to the sustainability of natural life is very important and has a history of 100 million years. The importance of bees and their by-products is increasing day by day, and the demand for the beekeeping industry as alternative income determines the emergence of new products and activities. Based on its health properties, apitherapy is the basis of activities such as api-air and api-diet. In natural regions (i.e., mountainous areas, forests) where beekeeping is carried out, people’s tradition, food culture, and healthy lifestyle attract society’s attention. In this context, api-tourist activity appears as a new phenomenon. In this article, the existing literature was scanned to create a resource about these new fields triggered by the beekeeping sector.

Fighting against the second wave of COVID-19: Can honeybee products help protect against the pandemic?

Coronavirus Disease (COVID-19) has infected people in 210 nations and has been declared a pandemic on March 12, 2020 by the World Health Organization (WHO). In the absence of effective treatment and/or vaccines for COVID-19, natural products of known therapeutic and antiviral activity could offer an inexpensive, effective option for managing the disease. Benefits of products of honey bees such as honey, propolis, and bee venom, against various types of diseases have been observed. Honey bees products are well known for their nutritional and medicinal values, they have been employed for ages for various therapeutic purposes. In this review, promising effects of various bee products against the emerging pandemic COVID-19 are discussed. Products of honey bees that contain mixtures of potentially active chemicals, possess unique properties that might help to protect, fight, and alleviate symptoms of COVID-19 infection.

Manuka honey: A promising wound dressing material for the chronic nonhealing discharging wounds: A retrospective study

OBJECTIVES

To assess the efficacy and feasibility of topical manuka honey application in chronic nonhealing discharging extraoral wounds.

MATERIALS AND METHODS

The study includes 15 patients (9 males and 6 females, mean age: 38.06, range: 20-50 years), presenting with the complaint of chronic nonhealing discharging extraoral wounds from January 2018 to January 2020. After wound irrigation with normal saline, manuka honey in conjunction with the antibiotic treatment was directly applied onto the surface of the wound and was then covered by an absorbent layer to contain the honey. Dressings were changed every alternate day for a week till there was complete cessation of pus discharge. Henceforth, the interval between dressings was increased to 1 week subsequently and was continued for 4 weeks. Assessment was done on the basis of discharge and depth of the wound before the procedure and weekly for 4 weeks.

RESULTS

The average depth of wound as seen at 15 sites after a week was 5.72 mm, and decrease in the average depth of wound seen at the end of the 4^th week was 0.88 mm with complete wound epithelization. This was found to be statistically significant (P = 0.0001). No cases were reported with allergy, pain, infection, inflammation, and swelling on 1^st, 2^nd, 3^rd, and 4^thweek.

CONCLUSION

Hence, the use of manuka honey as a wound dressing material in our study has proved to promote the growth of tissues for wound repair, suppress inflammation, and bring about rapid autolytic debridement.

Prospects of honey in fighting against COVID-19: pharmacological insights and therapeutic promises

Honey and its compounds are drawing attention as an effective natural therapy because of its ability to attenuate acute inflammation through enhancing immune response. Several studies have proved its potential healing capability against numerous chronic diseases/conditions, including pulmonary disorders, cardiac disorders, diabetes, hypertension, autophagy dysfunction, bacterial, and fungal infections. More importantly, honey has proved its virucidal effect on several enveloped viruses such as HIV, influenza virus, herpes simplex, and varicella-zoster virus. Honey may be beneficial for patients with COVID-19 which is caused by an enveloped virus SARS-CoV-2 by boosting the host immune system, improving comorbid conditions, and antiviral activities. Moreover, a clinical trial of honey on COVID-19 patients is currently undergoing. In this review, we have tried to summarize the potential benefits of honey and its ingredients in the context of antimicrobial activities, some chronic diseases, and the host immune system. Thus, we have attempted to establish a relationship with honey for the treatment of COVID-19. This review will be helpful to reconsider the insights into the possible potential therapeutic effects of honey in the context of the COVID-19 pandemic. However, the effects of honey on SARS-CoV-2 replication and/or host immune system need to be further investigated by in vitro and in vivo studies.

Proteomic analysis of honey. Identification of unique peptide markers for authentication of NZ mānuka (Leptospermum scoparium) honey

Proteomics is an emerging tool in food authentication that has not been optimised for honey analysis. In this study, we present a qualitative proteomic analysis of New Zealand mānuka (Leptospermum scoparium) honey. A total of fifty bee-derived proteins were identified in the honey, the most predominant being major royal jelly proteins (MRJPs). We also demonstrate for the first time the presence of unique nectar-derived proteins in mānuka honey. A total of 17 mānuka plant proteins were identified, a-third of which were putative pathogenesis-related proteins. Two proteins involved in drought tolerance were also identified. Twelve candidate peptides were selected as potential authentication markers based on their uniqueness to mānuka honey. Nectar analyses confirmed the origin and specificity of these peptides to L. scoparium nectar, thus presenting peptide profiling as a viable and novel approach for mānuka honey authentication. Raw data are available via ProteomeXchange with identifier PXD021730.

Physicochemical characteristics and antiproliferative and antioxidant activities of Moroccan Zantaz honey rich in methyl syringate

Zantaz honey is a monofloral variety produced from the melliferous plant Bupleurum spinosum (Apiaceae), a shrub that grows mainly in the Atlas Moroccan Mountains. Determination of the polyphenol composition revealed that methyl syringate accounts for more than 50% of total polyphenols, which represents a very useful parameter for the characterization of this monofloral honey. Epicatechin, syringic acid and catechin are also abundant. Caco-2 and THP-1 cells were used for determination of antioxidant and antiproliferative activities in Zantaz honey, respectively. All six commercial samples that were used for these studies exhibited antioxidant activity and inhibited cell proliferation. Interestingly, these activities had a positive correlation mainly with the content in methyl syringate and gallic acid. The recognition of health promoting activities in Zantaz honey should increase its commercial value, which would have a positive economic impact on the poor rural communities of Morocco where it is produced.

Effect of manuka honey on biofilm-associated genes expression during methicillin-resistant Staphylococcus aureus biofilm formation

Methicillin-resistant Staphylococcus aureus (MRSA) are among the most important biofilm-forming pathogens responsible for hard-to-treat infections. Looking for alternatives to antibiotics that prevent biofilm formation, we investigated the effects of manuka honey on the transcriptional profile of genes essential for staphylococcal biofilm formation using qRT-PCR. mRNA from two hospital MRSA strains (strong and weak biofilm producer) were isolated after 4, 8, 12 and 24 h from cells grown in biofilm. Manuka honey at 1/2 minimum biofilm inhibition concentration (MBIC) significantly reduced MRSA cell viability in biofilm. Manuka honey downregulated the genes encoding laminin- (eno), elastin- (ebps) and fibrinogen binding protein (fib), and icaA and icaD involved in biosynthesis of polysaccharide intercellular adhesin in both weakly and strongly adhering strain compared to the control (untreated biofilm). Expression levels of cna (collagen binding protein) and map/eap (extracellular adherence protein—Eap) were reduced in weakly adhering strain. The lowest expression of investigated genes was observed after 12 h of manuka honey treatment at 1/2 MBIC. This study showed that the previously unknown mechanism of manuka honey action involved inhibition of S. aureus adhesion due to reduction in expression of crucial genes associated with staphylococcal biofilm.

Anti-Biofilm Activities of Manuka Honey against Escherichia coli O157:H7

Manuka honey (MH) has been shown anti-bacterial activity against several pathogenic bacteria. However, the inhibitory effect of MH on biofilm formation by Escherichia coli O157:H7 has not yet been examined. In this study, MH significantly reduced E. coli O157:H7 biofilm. Moreover, pre- and post-treatment with MH also significantly reduced E. coli O157:H7 biofilm. Cellular metabolic activities exhibited that the viability of E. coli O157:H7 biofilm cells was reduced in the presence of MH. Further, colony forming unit of MH-treated E. coli O157:H7 biofilm was significantly reduced by over 70%. Collectively, this study suggests the potential of anti-biofilm properties of MH which could be applied to control E. coli O157:H7.

Effectiveness of Topical Application of Honey on Oral Mucosa of Children for the Management of Oral Mucositis Associated with Chemotherapy

OBJECTIVE

To evaluate the effectiveness of topical application of honey on Oral Mucositis (OM) associated with chemotherapy.

METHODS

An observational blind study is performed upon a sample of 100 children receiving chemotherapy who developed oral mucositis. All children are divided into two groups (control and experimental) who received different regimens. Both groups received routine practice of analgesic and antiseptic gel application whereas children in experimental group also received the topical application of honey on oral mucosa for the management of OM. All children are monitored from the day they developed oral mucositis until the subsidence of signs and symptoms of oral mucositis. The severity of OM was assessed with WHO-STC (Stomatitis Toxicity Criteria) scale by a observer blind.

RESULTS

There was statistically significant difference in reduction of severity of OM in both groups of children (p < 0.01). The duration of management of OM was significantly small in the experimental group (median 4 d, IQR: 4-6 d) as compared to the control group (median 6 d, IQR: 6-8 d) (p < 0.01).

CONCLUSIONS

The topical application of honey on oral mucosa was effective in reducing the severity and duration of management of chemotherapy induced oral mucositis (CIOM; p < 0.05) and that means honey is a good quality product with rich nutritious value and would be a pleasant, simple and cost-effective modality for the management of oral mucositis associated with chemotherapy.

Manuka Honey Modulates the Inflammatory Behavior of a dHL-60 Neutrophil Model under the Cytotoxic Limit

Recent work has shown that Manuka honey, an increasingly popular wound additive with potent antibacterial properties, also has anti-inflammatory properties. However, little research has been done examining its effect on neutrophils. This study investigates the hypothesis that Manuka honey reduces neutrophil superoxide release and chemotaxis and reduces the activation of the inflammatory nuclear factor-κB (NF-κB) signaling pathway under honey's cytotoxic limit. A differentiated HL-60 cell line was used as a neutrophil model and cultured in various concentrations of Manuka honey for 3 and 24 hours to measure cytotoxicity via mitochondrial activity and visual trypan-exclusion count. Cytochrome C and Boyden chamber assays were used to measure the effect of Manuka honey on superoxide release and chemotaxis toward fMLP, respectively. Additionally, a Western blot for NF-κB inhibitor α (IκBα) was performed to measure Manuka honey's effect on the NF-κB pathway via IκBα phosphorylation. The results indicate a cytotoxic limit of 3-5% v/v. The presence of 1% honey decreased superoxide release at 24 hours. The 0.5, 1, and 3% honey concentrations reduced chemotaxis and IκBα phosphorylation in a dose-dependent fashion. These results suggest that Manuka honey significantly reduces neutrophil recruitment and inflammatory behavior in the wound site in a dose-dependent fashion under the cytotoxic limit.

Honey, Propolis, and Royal Jelly: A Comprehensive Review of Their Biological Actions and Health Benefits

BACKGROUND

There are several health benefits that honeybee products such as honey, propolis, and royal jelly claim toward various types of diseases in addition to being food.

SCOPE AND APPROACH

In this paper, the effects of honey, propolis, and royal jelly on different metabolic diseases, cancers, and other diseases have been reviewed. The modes of actions of these products have also been illustrated for purposes of better understanding.

KEY FINDINGS AND CONCLUSIONS

An overview of honey, propolis, and royal jelly and their biological potentials was highlighted. The potential health benefits of honey, such as microbial inhibition, wound healing, and its effects on other diseases, are described. Propolis has been reported to have various health benefits related to gastrointestinal disorders, allergies, and gynecological, oral, and dermatological problems. Royal jelly is well known for its protective effects on reproductive health, neurodegenerative disorders, wound healing, and aging. Nevertheless, the exact mechanisms of action of honey, propolis, and royal jelly on the abovementioned diseases and activities have not been not fully elucidated, and further research is warranted to explain their exact contributions.

A systems biology approach to investigate the antimicrobial activity of oleuropein

Oleuropein and its hydrolysis products are olive phenolic compounds that have antimicrobial effects on a variety of pathogens, with the potential to be utilized in food and pharmaceutical products. While the existing research is mainly focused on individual genes or enzymes that are regulated by oleuropein for antimicrobial activities, little work has been done to integrate intracellular genes, enzymes and metabolic reactions for a systematic investigation of antimicrobial mechanism of oleuropein. In this study, the first genome-scale modeling method was developed to predict the system-level changes of intracellular metabolism triggered by oleuropein in Staphylococcus aureus, a common food-borne pathogen. To simulate the antimicrobial effect, an existing S. aureus genome-scale metabolic model was extended by adding the missing nitric oxide reactions, and exchange rates of potassium, phosphate and glutamate were adjusted in the model as suggested by previous research to mimic the stress imposed by oleuropein on S. aureus. The developed modeling approach was able to match S. aureus growth rates with experimental data for five oleuropein concentrations. The reactions with large flux change were identified and the enzymes of fifteen of these reactions were validated by existing research for their important roles in oleuropein metabolism. When compared with experimental data, the up/down gene regulations of 80% of these enzymes were correctly predicted by our modeling approach. This study indicates that the genome-scale modeling approach provides a promising avenue for revealing the intracellular metabolism of oleuropein antimicrobial properties.

Antioxidant, Anti-inflammatory, and Antiulcer Potential of Manuka Honey against Gastric Ulcer in Rats

Gastric ulcers are among the most common diseases affecting humans. This study aimed at investigating the gastroprotective effects of manuka honey against ethanol-induced gastric ulcers in rats. The mechanism by which honey exerts its antiulcer potential was elucidated. Four groups of rats were used: control, ethanol (ulcer), omeprazole, and manuka honey. Stomachs were examined macroscopically for hemorrhagic lesions in the glandular mucosa, histopathological changes, and glycoprotein detection. The effects of oxidative stress were investigated using the following indicators: gastric mucosal nitric oxide (NO), reduced glutathione (GSH), lipid peroxide (MDA, measured as malondialdehyde) glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase. Plasma tumour necrosis factor-α, interleukin-1β, and IL-6 were also measured. Manuka honey significantly decreased the ulcer index, completely protected the mucosa from lesions, and preserved gastric mucosal glycoprotein. It significantly increased gastric mucosal levels of NO, GSH, GPx, and SOD. Manuka honey also decreased gastric mucosal MDA and plasma TNF-α, IL-1β, and IL-6 concentrations. In conclusion, manuka honey likely exerted its antiulcer, effect by keeping enzymatic (GPx and SOD) and nonenzymatic (GSH and NO) antioxidants as well as inflammatory cytokines (TNF-α, IL-1β, and IL-6) in a reduced form, inhibited lipid peroxidation (MDA), and preserved mucous glycoproteins levels.

The Composition and Biological Activity of Honey: A Focus on Manuka Honey

Honey has been used as a food and medical product since the earliest times. It has been used in many cultures for its medicinal properties, as a remedy for burns, cataracts, ulcers and wound healing, because it exerts a soothing effect when initially applied to open wounds. Depending on its origin, honey can be classified in different categories among which, monofloral honey seems to be the most promising and interesting as a natural remedy. Manuka honey, a monofloral honey derived from the manuka tree (Leptospermum scoparium), has greatly attracted the attention of researchers for its biological properties, especially its antimicrobial and antioxidant capacities. Our manuscript reviews the chemical composition and the variety of beneficial nutritional and health effects of manuka honey. Firstly, the chemical composition of manuka honey is described, with special attention given to its polyphenolic composition and other bioactive compounds, such as glyoxal and methylglyoxal. Then, the effect of manuka honey in wound treatment is described, as well as its antioxidant activity and other important biological effects.