Flavonoids from italian multifloral honeys reduce the extracellular ferricyanide in human red blood cells

Inhibition of Skin Pathogenic Bacteria, Antioxidant and Anti-Inflammatory Activity of Royal Jelly from Northern Thailand

Royal jelly is a nutritious substance produced by the hypopharyngeal and mandibular glands of honeybees. Royal jelly possesses many attractive and beneficial properties which make it an ideal component in medical and pharmaceutical products. The antibacterial, antioxidant, and anti-inflammatory activities of royal jelly from honeybees (Apis mellifera) were determined in this study. Moreover, the total phenolic and flavonoid contents of the royal jelly were also evaluated. The effects of royal jelly on growth inhibition against skin pathogenic bacteria, including Cutibacterium acnes, methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis, and Corynebacterium spp., were investigated by the agar well diffusion method. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were further determined by the broth dilution method. The results indicated that royal jelly showed antibacterial activity by inhibiting the growth of Gram-positive pathogenic bacteria, while the effectiveness decreased against Gram-negative bacteria. Interestingly, royal jelly from Lamphun (RJ-LP1), and Chiang Mai (RJ-CM1), presented high inhibitory efficacy against C. acnes, MRSA, and S. aureus within 4 h by a time killing assay. Furthermore, the anti-inflammatory properties of royal jelly were tested using RAW264.7 macrophage cells, and results revealed that RJ-LP1 and RJ-CM1 could reduce nitric oxide (NO) production and suppress iNOS gene expression. After testing the antioxidant activity, RJ-CM1 and RJ-CM2 of royal jelly from Chiang Mai had the highest level. Additionally, RJ-CM1 also showed the highest total phenolic and flavonoid content. These findings have brought forward new knowledge of the antibacterial, antioxidant, and anti-inflammatory properties of royal jelly, which will improve clinical and pharmaceutical uses of royal jelly as an alternative therapy for bacterial infections, and also as a dietary supplement product.

Increase in longevity and amelioration of pesticide toxicity by natural levels of dietary phytochemicals in the honey bee, Apis mellifera

For the past decade, migratory beekeepers who provide honey bees for pollination services have experienced substantial colony losses on a recurring basis that have been attributed in part to exposure to insecticides, fungicides, or their combinations applied to crops. The phytochemicals p-coumaric acid and quercetin, which occur naturally in a wide variety of bee foods, including beebread and many types of honey, can enhance adult bee longevity and reduce the toxicity of certain pesticides. How variation in concentrations of natural dietary constituents affects interactions with xenobiotics, including synthetic pesticides, encountered in agroecosystems remains an open question. We tested the effects of these two phytochemicals at a range of natural concentrations on impacts of consuming propiconazole and chlorantraniliprole, a triazole fungicide and an insecticide frequently applied as a tank mix to almond trees during bloom in California's Central Valley. Propiconazole, even at low field concentrations, significantly reduced survival and longevity when consumed by adult bees in a sugar-based diet. The effects of propiconazole in combination with chlorantraniliprole enhanced mortality risk. The detrimental effects of the two pesticides were for the most part reduced when either or both of the phytochemicals were present in the diet. These findings suggest that honey bees may depend on non-nutritive but physiologically active phytochemical components of their natural foods for ameliorating xenobiotic stress, although only over a certain range of concentrations; particularly at the high end of the natural range, certain combinations can incur additive toxicity. Thus, efforts to develop nectar or pollen substitutes with phytochemicals to boost insecticide tolerance or immunity or to evaluate toxicity of pesticides to pollinators should take concentration-dependent effects of phytochemicals into consideration.

Mast Cell Regulation and Irritable Bowel Syndrome: Effects of Food Components with Potential Nutraceutical Use

Mast cells are key actors in inflammatory reactions. Upon activation, they release histamine, heparin and nerve growth factor, among many other mediators that modulate immune response and neuron sensitization. One important feature of mast cells is that their population is usually increased in animal models and biopsies from patients with irritable bowel syndrome (IBS). Therefore, mast cells and mast cell mediators are regarded as key components in IBS pathophysiology. IBS is a common functional gastrointestinal disorder affecting the quality of life of up to 20% of the population worldwide. It is characterized by abdominal pain and altered bowel habits, with heterogeneous phenotypes ranging from constipation to diarrhea, with a mixed subtype and even an unclassified form. Nutrient intake is one of the triggering factors of IBS. In this respect, certain components of the daily food, such as fatty acids, amino acids or plant-derived substances like flavonoids, have been described to modulate mast cells' activity. In this review, we will focus on the effect of these molecules, either stimulatory or inhibitory, on mast cell degranulation, looking for a nutraceutical capable of decreasing IBS symptoms.

Protective effect of the medicinal herb infusion "horchata" against oxidative damage in cigarette smokers: An ex vivo study

Cigarette smoking has been associated with an increase in oxidative stress (OS) and is considered a predisposing factor to chronic noncommunicable diseases, whilst dietary antioxidants has been proposed as an alternative to cope with this oxidative stress. In this study, 20 smokers and 20 non-smokers were studied with the aim of determining their antioxidant status, as well as the ability of an infusion of 23 medicinal plants, to counteract the damage caused by OS. The plasma, red blood cells (RBCs) and polymorphonuclear cells (PBMCs) of both groups were incubated or not with the horchata infusion extract and then the OS markers, genotoxicity, nanostructure of RBCs membrane and genes related to oxidative responses and cellular functionality were evaluated. Up to 33 different compounds, mainly quercetin glycosides, were identified in the extract. A significant deterioration in the antioxidant status in smokers compared to non-smokers was found. The horchata infusion extract improved the nanostructure of RBCs and DNA damage, as well as the activity of the endogenous antioxidant enzymes and markers of oxidative damage to lipid, and proteins in plasma, RBCs and PBMCs in both groups, whilst no significant changes were found in the expression of different genes related to OS response.

Effects of honey supplementation on safety profiles among postmenopausal breast cancer patients

Objectives

In this study, we aimed to determine the effect of honey supplementation on the safety profiles of postmenopausal breast cancer patients.

Methods

Seventy-two postmenopausal women with stage I, II, or III breast cancer from the Oncology Clinic, Universiti Sains Malaysia Hospital were treated with anastrozole (1 mg/day). Patients were randomly assigned to one of the two groups (n = 36/group): a control group (no honey) and a honey group (20 g/day of honey for 12 weeks). Fasting blood samples were obtained pre- and post-intervention to investigate differences in the haematological, renal, and liver profiles of patients in both the groups.

Results

Post-intervention, alanine aminotransferase levels were significantly higher in the control group than in the honey group. In the honey group, white blood cell counts, platelet counts, and creatinine levels were significantly higher following honey supplementation for 12 weeks. Nevertheless, the values were still within normal ranges.

Conclusions

The present study suggests that honey supplementation of 20 g/day for 12 weeks is safe and beneficial for postmenopausal breast cancer patients.

Honey and Its Role in Relieving Multiple Facets of Atherosclerosis

Honey, a natural sweetener has been used universally as a complete food and in complementary medicine since early antiquity. Honey contains over 180 substances, including sugars mainly fructose and glucose, water and a plethora of minor constituents such as vitamins, minerals and phytochemicals. The chemical composition of honey varies depending on floral origin, environment and geographical conditions. The sugar components dominate honey composition and they are accountable for sensory and physicochemical properties in food industry. Although present in small quantities, non-sugar components are the major contributors to the health benefits of honey. Our review summarizes and discusses composition of honey, its protective effects and possible action modes on risk factors of atherosclerosis.

Preventive effects of royal jelly against anaphylactic response in a murine model of cow's milk allergy

CONTEXT

Royal jelly (RJ) has long been used to promote human health.

OBJECTIVE

The current study investigated the preventive effects of RJ against the development of a systemic and intestinal immune response in mice allergic to cow's milk proteins.

MATERIALS AND METHODS

Balb/c mice treated orally for seven days with RJ at doses of 0.5, 1 and 1.5 g/kg were sensitized intraperitoneally with β-lactoglobulin (β-Lg). Serum IgG and IgE anti-β-Lg were determined by an enzyme-linked immunosorbent assay (ELISA). Plasma histamine levels, symptom scores and body temperature were determined after in vivo challenge to β-Lg. Jejunums were used for assessment of local anaphylactic responses by an ex vivo study in Ussing chambers and morphologic changes by histological analysis.

RESULTS

RJ significantly decreased serum IgG (31.15-43.78%) and IgE (64.28-66.6%) anti-β-Lg and effectively reduced plasma histamine level (66.62-67.36%) (p < 0.001) at all the doses tested. Additionally, no clinical symptoms or body temperature drops were observed in RJ-pretreated mice. Interestingly, RJ significantly reduced (p < 0.001) intestinal dysfunction by abolishing the secretory response (70.73-72.23%) induced by sensitization and prevented length aberrations of jejunal villi by 44.32-59.01% (p < 0.001).

DISCUSSION AND CONCLUSIONS

We speculate that using RJ may help prevent systemic and anaphylactic response in allergic mice. These effects may be related to its inhibitory effects on the degranulation of mast cells.

Beneficial Effects of Capparis Spinosa Honey on the Immune Response of Rats Infected with Toxoplasma Gundii

Objectives

The Toxoplasma gondii (T. gondii) is an intracellular opportunistic protozoan parasite that infects approximately one-third of the human population worldwide. Honey has long been used for treatment of many diseases in folk medicine. Honey has exhibited significant anthelmintic, nematicidal and anti-protozoal activities.This study was conducted to investigate the immunological patterns in rats infected with T. gondii who were treated orally with supplemented 15% Capparis spinosa honey (Saudi Arabia) for a period of 28 days.

Methods

Immunoglobulin M, immunoglobulin G, and cytokines were detected by using enzyme-linked immunosorbent assays (ELISAs). In addition, the mortality and the morbidity rates were assessed.

Results

Oral administration of Capparis spinosa honey as a natural food additive was experimentally shown to increase the antibody titer; furthermore, compared with the rats in the control group, the levels of the sera cytokines (IFN-γ, IL-1 and IL-6) were consistently higher at day 7 post-infection in the infected rats treated with oral supplements of Capparis spinosa honey.

Conclusion

Orally administered supplements of Capparis spinosa honey increased both the antibody titer and the cytokines (IFN-γ, IL-1 and IL-6) levels in rats infected with T. gondii.

The anti-cancer effects of Tualang honey in modulating breast carcinogenesis: an experimental animal study

Background

Honey has been shown to have anti-cancer effects, but the mechanism behind these effects is not fully understood. We investigated the role of Malaysian jungle Tualang honey (TH) in modulating the hematological parameters, estrogen, estrogen receptors (ER1) and pro and anti-apoptotic proteins expression in induced breast cancer in rats.

Methods

Fifty nulliparous female Sprague–Dawley rats were used and grouped as follows: Group 0 (healthy normal rats control), Group 1 (negative control; untreated rats), Groups 2, 3 and 4 received daily doses of 0.2, 1.0 and 2.0 g/kg body weight of TH, respectively. The rats in groups 1, 2, 3, 4 were induced with 80 mg/kg of 1-methyl-1-nitrosourea (MNU). TH treatment in groups 2, 3 and 4 was started one week prior to tumor induction and continued for 120 days.

Results

The TH-treated rats had tumors of different physical attributes compared to untreated negative control rats; the tumor progression (mean 75.3 days versus 51.5 days); the incidence (mean 76.6% versus 100%); the multiplicity (mean 2.5 versus 4 tumor masses per rat); the size of tumor mass (mean 0.41 cm versus 1.47 cm [p < 0.05]) and the weight of the tumor mass (mean 1.22 g versus 3.23 g; [p < 0.05]). Histological examinations revealed that cancers treated with TH were mainly of grades I and II compared with the non-treated control, in which the majority were of grade III (p < 0.05). TH treatment was found to modulate hematological parameters such as Hb, RBCs, PCV, MCV, RDW, MCHC, polymorphs and lymphocytes values. TH treatment groups were found to have a lower anti-apoptotic proteins (E2, ESR1 and Bcl-xL) expression and a higher pro-apoptotic proteins (Apaf-1 and Caspase-9) expression at serum and on cancer tissue level (p < 0.05).

Conclusion

Tualang Honey alleviates breast carcinogenesis through modulation of hematologic, estrogenic and apoptotic activities in this experimental breast cancer animal model. Tualang Honey may be used as a natural ‘cancer-alleviating’ agent or as a supplement to chemotherapeutic agents.

Histopathological and biochemical investigations of protective role of honey in rats with experimental aflatoxicosis

Background

Natural honey (honey) is considered as a part of traditional medicine all over the world. It has both antimicrobial and antioxidant properties, useful in stimulation of wounds and burns healing and gastric ulcers treatment. The aim of this study, for the first time, was to investigate the antioxidant properties and protective role of honey against carcinogen chemical aflatoxin (AF) exposure in rats, which were evaluated by histopathological changes in liver and kidney, measuring level of serum marker enzymes [aspartate aminotransferase (AST), alanin aminotransferase (ALT), gamma glutamil transpeptidase (GGT)], antioxidant defense systems [Reduced glutathione (GSH), glutathione reductase (GR), superoxide dismutase (SOD), glutathione-S-transferase (GST) and catalase (CAT)], and lipid peroxidation content in liver, erythrocyte, brain, kidney, heart and lungs.

Methods

Eighteen healthy Sprague–Dawley rats were randomly allocated into three experimental groups: A (Control), B (AF-treated) and C (AF + honey-treated). While rats in group A were fed with a diet without AF, B, and C groups received 25 μg of AF/rat/day, where C group additionally received 1 mL/kg of honey by gavage for 90 days.

Results

At the end of the 90-day experimental period, we found that the honey supplementation decreased the lipid peroxidation and the levels of enzyme associated with liver damage, increased enzymatic and non-enzymatic antioxidants in the AF + honey-treated rats. Hepatoprotective and nephroprotective effects of honey is further substantiated by showing almost normal histological architecture in AF + honey-treated group, compared to degenerative changes in the liver and kidney of AF-treated rats. Additionally, honey supplementation ameliorated antioxidant defens systems and lipid peroxidation in content in other tissues of AF + honey treated rats.

Conclusion

The present study indicates that honey has a hepatoprotective and nephroprotective effect in rats with experimental aflatoxicosis due to its antioxidant activity.

Red wine activates plasma membrane redox system in human erythrocytes

In the present study, we report that polyphenols present in red wine obtained by a controlled microvinification process are able to protect human erythrocytes from oxidative stress and to activate Plasma Membrane Redox System (PMRS). Human plasma obtained from healthy subjects was incubated in the presence of whole red wine at a concentration corresponding to 9.13-73 μg/ml gallic acid equivalents to verify the capacity to protect against hypochlorous acid (HOCl)-induced plasma oxidation and to minimize chloramine formation. Red wine reduced hemolysis and chloramine formation induced by HOCl of 40 and 35%, respectively. PMRS present on human erythrocytes transfers electrons from intracellular molecules to extracellular electron acceptors. We demonstrated that whole red wine activated PMRS activity in human erythrocytes isolated from donors in a dose-dependent manner with a maximum at about 70-100 μg/ml gallic acid equivalents. We also showed that red wine increased glutathione (GSH) levels and erythrocytic antioxidant capacity, measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) quenching assay. Furthermore, we reported that GSH played a crucial role in regulating PMRS activity in erythrocytes. In fact, the effect of iodoacetamide, an alkylating agent that induces depletion of intracellular GSH, was completely counteracted by red wine. Bioactive compounds present in red wine, such as gallic acid, resveratrol, catechin, and quercetin were unable to activate PMRS when tested at the concentrations normally present in aged red wines. On the contrary, the increase of PMRS activity was associated with the anthocyanin fraction, suggesting the capacity of this class of compounds to positively modulate PMRS enzymatic activity.

Inhibitory effects of sodium arsenite and acacia honey on acetylcholinesterase in rats

This study was conducted to investigate the effect of sodium arsenite and Acacia honey on acetylcholinesterase (AChE) activity and electrolytes in the brain and serum of Wistar rats. Male Wistar albino rats in four groups of five rats each were treated with distilled water, sodium arsenite (5 mg/kg body weight), Acacia honey (20% v/v), and sodium arsenite and Acacia honey, daily for one week. The sodium arsenite and Acacia honey significantly (P < 0.05) decreased AChE activity in the brain with the combined treatment being more potent. Furthermore, sodium arsenite and Acacia honey significantly (P < 0.05) decreased AChE activity in the serum. Strong correlation was observed between the sodium and calcium ion levels with acetylcholinesterase activity in the brain and serum. The gas chromatography mass spectrometry analysis of Acacia honey revealed the presence of a number of bioactive compounds such as phenolics, sugar derivatives, and fatty acids. These findings suggest that sodium arsenite and/or Acacia honey modulates acetylcholinesterase activities which may be explored in the management of Alzheimer's diseases but this might be counteracted by the hepatotoxicity induced by arsenics.

Effect of royal jelly on formalin induced-inflammation in rat hind paw

BACKGROUND

Royal Jelly (RJ), a food item secreted by worker honeybees, is a mixture that contains protein, glucose, lipid, vitamins, and minerals; it is widely used as a commercial medical product. Previous studies have shown that RJ has a number of physiological effects, such as anti-inflammatory, antitumor, antiallergic and antioxidant activities.

OBJECTIVES

In the present study, the anti-inflammatory properties of RJ were investigated in formalin-induced rat paw edema.

MATERIALS AND METHODS

In this study, 30 male Wistar albino rats were divided into five equal groups (n = 6) as follows: test groups received different doses (25, 50 and 100 mg/kg, ip) of RJ and a negative control group received normal saline (5 mL/kg) and a positive control group received aspirin (300 mg/kg, i.p). Edema was induced on the right hind paw of the rat by a subplantar injection of 100 µL of formalin (2.5%) after 30 minutes. Paw edema was measured in the rats received the drugs, saline and aspirin before and after the formalin injection during 5 hours, using a plethysmometer.

RESULTS

The results showed that RJ has a dose-dependent anti-inflammatory effect and the highest anti-inflammatory effect was observed in the doses of 50 and 100 mg/kg.

CONCLUSIONS

Royal jelly has potent anti-inflammatory effects compared to aspirin and it could be used in the treatment of inflammation. However, further studies are required to determine the active components in RJ responsible for this effect and its mechanism of action.

Honey flavonoids inhibit Candida albicans morphogenesis by affecting DNA behavior and mitochondrial function

AIM

Candida albicans is a pathogenic yeast, which forms a range of polarized and expanded cell shapes. We aimed to determine the correlation between honey extract (HFE) activity and changes in C. albicans cell cycle, morphology and subcellular organelles.

MATERIALS & METHODS

HFE anticandidal properties were investigated using flow cytometry and scanning electron microscopy.

RESULTS

Flow cytometry and scanning electron microscopy analyses indicated that HFE may inhibit the growth of the three phenotypes displayed by C. albicans and reduce infection by affecting membrane integrity. HFE affects hyphal transition by reducing the G0/G1 phase and increasing the G2/M phase. Conversely, yeast and pseudohyphae do not appear to be affected. Modifications of vacuolization and mitochondrial activity, during yeast-hypha transition establish the involvement of vacuole and mitochondria.

CONCLUSION

HFE improved mitochondrial functionality and reduced the vacuolization, modifying the branching process associated with virulence. It is hypothesized that HFE induces changes in cell cycle progress, membrane integrity, mitochondrial function and biogenesis.

Molecular mechanism of antiproliferation potential of Acacia honey on NCI-H460 cell line

Lung cancer is one of the leading causes of death worldwide. We investigated the molecular mechanism of antiproliferation potential of Acacia honey on NCI-H460 cells by cell cycle, viability, cytokines, calcium ion and gene expression analysis. Acacia honey inhibited cells proliferation, arrested G0/G1 phase, stimulated cytokines, calcium ion release as well as suppressed p53 and Bcl-2 expression in a dose-dependent manner. We proposed that the molecular mechanism of the antiproliferation potential of Acacia honey on NCI-H460 cell line is due to cell cycle arrest, stimulation of cytokines and calcium ion as well as downregulation of Bcl-2 and p53 genes.

Spanish honeys protect against food mutagen-induced DNA damage

BACKGROUND

Honey contains a variety of polyphenols and represents a good source of antioxidants, while the human diet often contains compounds that can cause DNA damage. The present study investigated the protective effect of three commercial honey samples of different floral origin (rosemary, heather and heterofloral) from Madrid Autonomic Community (Spain) as well as an artificial honey on DNA damage induced by dietary mutagens, using a human hepatoma cell line (HepG2) as in vitro model system and evaluation by the alkaline single-cell gel electrophoresis or comet assay.

RESULTS

Rosemary, heather and heterofloral honeys protected against DNA strand breaks induced by N-nitrosopyrrolidine (NPYR), benzo(a)pyrene (BaP) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), but none of the honey samples tested prevented DNA strand breaks induced by N-nitrosodimethylamine (NDMA). Heterofloral and heather (unifloral) honeys with higher phenolic content were most effective in protecting HepG2 cells against DNA damage induced by food mutagens. Heterofloral honey was more protective against NPYR and BaP, while heather honey was more protective against PhIP. Artificial honey did not show a protective effect against DNA damage induced by any of the food mutagens tested, indicating that the protective effects of honeys could not be due to their sugar components.

CONCLUSION

The results suggest that the protective effect of three kinds of Spanish honey of different floral origin could be attributed in part to the phenolics present in the samples. Honeys with higher phenolic content, i.e. heather and heterofloral honeys, were most effective in protecting against food mutagen-induced DNA damage in HepG2 cells. In addition, a possible synergistic effect between other minor honey components could also be involved.

Bees' honey protects the liver of male rats against melamine toxicity

The protective effect of natural bees' honey to the liver of male albino rats against melamine toxicity was studied. Melamine supplementation at a dose of 20000 ppm in the diet for 28 days induced adverse effects on the liver, decreased serum total protein and increased liver enzyme: alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase. Histological changes of the melamine supplemented group showed necrosis in the hepatic tissues around the central veins of the liver and precipitation of melamine crystals. Treating the male albino rats (that were presupplemented regularly with 20000 ppm melamine) with natural bees' honey at a dose of 2.5 g/kg body weight for 28 days improved both liver functions and increased serum protein. In addition, a positive impact on the shape of the cells after treatment with honey compared to the positive melamine supplemented group was observed. In conclusion, the results of this study revealed that the use of natural bees' honey has the ability to protect the liver of rats against the toxic effects of melamine.

Anti-inflammatory activity of a honey flavonoid extract on lipopolysaccharide-activated N13 microglial cells

Neuroinflammation is an important contributor to pathogenesis of age-related neurodegenerative disorders such as Alzheimer's or Parkinson's disease. Accumulating evidence indicates that inhibition of microglia-mediated neuroinflammation may become a reliable protective strategy for neurodegenerative processes. Flavonoids, widely distributed in the vegetable kingdom and in foods such as honey, have been suggested as novel therapeutic agents for the reduction of the deleterious effects of neuroinflammation. The present study investigated the potential protective effect of a honey flavonoid extract (HFE) on the production of pro-inflammatory mediators by lipopolysaccharide-stimulated N13 microglia. The results show that HFE significantly inhibited the release of pro-inflammatory cytokines such as TNF-α and IL-1β. The expressions of iNOS and the production of reactive oxygen intermediates (ROS) were also significantly inhibited. Accordingly, the present study demonstrates that HFE is a potent inhibitor of microglial activation and thus a potential preventive-therapeutic agent for neurodegenerative diseases involving neuroinflammation.

How do erythrocytes contribute to the ABTS* scavenging capacity of blood?

It has been suggested lately that erythrocytes contribute significantly to the oxidant scavenging capacity (OSC) of blood and that surface adsorption of polyphenols enhances the antioxidant capacity of erythrocytes. The aim of this study was to examine the contribution of erythrocytes to the OSC of whole blood measured with a substrate not penetrating into the cells. Comparison of reduction of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical (ABTS*) by whole blood and blood plasma indicates that erythrocytes do contribute to ABTS* reduction but their contribution is lower with respect to plasma. ABTS* reduction by erythrocytes and its enhancement by polyphenols were inhibited by thiol reagents (N-ethylmaleimide and iodacetate). These reagents inhibited also the reduction of extracellular ferricyanide by erythrocytes and its enhancement by polyphenols. On this basis we postulate that the contribution of erythrocytes to the blood OSC estimated by ABTS* decolorization is at least partly due to the transmembrane-reducing system, which activity is routinely assayed by ferricyanide reduction.

Erythrocyte antioxidant protection of rose hips (Rosa spp.)

Rose hips are popular in health promoting products as the fruits contain high content of bioactive compounds. The aim of this study was to investigate whether health benefits are attributable to ascorbic acid, phenols, or other rose-hip-derived compounds. Freeze-dried powder of rose hips was preextracted with metaphosphoric acid and the sample was then sequentially eluted on a C₁₈ column. The degree of amelioration of oxidative damage was determined in an erythrocyte in vitro bioassay by comparing the effects of a reducing agent on erythrocytes alone or on erythrocytes pretreated with berry extracts. The maximum protection against oxidative stress, 59.4 ± 4.0% (mean ± standard deviation), was achieved when incubating the cells with the first eluted meta-phosphoric extract. Removal of ascorbic acid from this extract increased the protection against oxidative stress to 67.9 ± 1.9%. The protection from the 20% and 100% methanol extracts was 20.8 ± 8.2% and 5.0 ± 3.2%, respectively. Antioxidant uptake was confirmed by measurement of catechin by HPLC-ESI-MS in the 20% methanol extract. The fact that all sequentially eluted extracts studied contributed to protective effects on the erythrocytes indicates that rose hips contain a promising level of clinically relevant antioxidant protection.

Phenolics from monofloral honeys protect human erythrocyte membranes against oxidative damage

The aim of the present work was to analyze the phenolic extracts from two monofloral Cuban honeys for their in vitro total antioxidant capacity, phenolic compounds content and free radical scavenging activity. The phenolic extracts, rich in lipophilic compounds, were tested further for their ability to inhibit AAPH-induced oxidative damage (hemolysis, lipid peroxidation and cytosolic depletion of reduced glutathione and decrease of superoxide dismutase activity) in erythrocytes. Results indicate an important total antioxidant capacity measured by TEAC and ORAC assays, as well as a relevant radical scavenging activity performed by EPR. Moreover, 13 phenolic compounds were identified using HPLC-LC/MS with quercetin as the most abundant flavonoid. The results also show that both extracts were able to inhibit erythrocytes oxidative damage, and that this may likely be due to their incorporation into cell membranes and their ability to cross it and reach the cytosol. In fact, flavonoid uptake by erythrocytes was further confirmed by testing quercetin, which efficiently incorporated into erythrocytes. Overall, this study indicates that honey contains relevant antioxidant compounds responsible, at least in part, for its biological activity and that uptake of its flavonoids may provide defense and promote cell functions in erythrocytes.

Analysis of flavonoids in honey by HPLC coupled with coulometric electrode array detection and electrospray ionization mass spectrometry

The analysis of flavonoids in unifloral honeys by high-performance liquid chromatography (HPLC) coupled with coulometric electrode array detection (CEAD) is described. The compounds were extracted by a nonionic polymeric resin (Amberlite XAD-2) and then separated on a reversed phase column using gradient elution. Quercetin, naringenin, hesperetin, luteolin, kaempferol, isorhamnetin, and galangin were detected in a coulometric electrode array detection system between +300 and +800 mV against palladium reference electrodes, and their presence was additionally confirmed by HPLC coupled with electrospray ionization mass spectrometry. The method was applied to analysis of 19 honeys of different varieties and origin. The limits of detection and quantitation ranged between 1.6 and 8.3 μg/kg and 3.9 and 27.4 μg/kg, respectively. The recoveries were above 96% in fluid and above 89% in creamy honeys. Some of these honeys (melon, pumpkin, cherry blossom, dandelion, maple, and pine tree honey) were investigated for their flavonoid content and profile for the first time. Differences between honeys were observed both in flavonoid concentrations and in the flavonoid profiles. The flavonoid concentrations ranged from 0.015 to 3.4 mg/kg honey. Galangin, kaempferol, quercetin, isorhamnetin, and luteolin were detected in all investigated honeys, whereas hesperetin occurred only in lemon and orange honeys and naringenin in lemon, orange, rhododendron, rosemary, and cherry blossom honeys.

The relationships between phenolic content, pollen diversity, physicochemical information and radical scavenging activity in honey

Honey is rich in different secondary plant metabolites acting as natural antioxidants and contributing to human health. Radical scavenging activity (RSA) is related to antioxidant activity, while the correlation between the phenolic content and RSA is often weak. Consequently, exclusive information on phenolics is often insufficient to qualify the RSA and the health promoting effects of honey. The paper deals with a case study of honey samples originating from the alpine areas of Italy’s Lombardia and Veneto regions and realized by standard physicochemical and statistical analytical methods. In pure honey, the total phenolic content and the RSA were measured in spectrophotometric tests with the 2,2-diphenyl-1-picrylhydrazyl (DPPH·) free radical and Folin-Ciocalteu assays, respectively. Melissopalynological data was used to qualify pollen diversity through rank-frequency curves separating the samples into two groups. On the basis of physicochemical data, the samples were analyzed through multivariate classification and ranking procedures resulting in the identification of an outlier. Elimination of the outlier produced a high correlation between the total phenolic content and RSA in the two pollen diversity groups. The case study suggests that, after disregarding outliers, the RSA activity can be satisfactorily qualified on the basis of phenolics with pollen diversity as a covariate.

Effect of royal jelly on experimental colitis Induced by acetic acid and alteration of mast cell distribution in the colon of rats

This study investigated the effects of royal jelly (RJ) on acetic acid-induced colitis in rats. Twenty adult female Wistar albino rats were divided into four treatment groups of 5 animals each, including a control group (Group I); Group II was treated orally with RJ (150 mg kg(-1) body weight); Group III had acetic acid-induced colitis; and Group IV had acetic acid-induced colitis treated orally with RJ (150 mg kg(-1) body weight) for 4 weeks. Colitis was induced by intracolonic instillation of 4% acetic acid; the control group received physiological saline (10 mL kg(-1)). Colon samples were obtained under deep anaesthesia from animals in all groups. Tissues were fixed in 10% formalin neutral buffer solution for 24 h and embedded in paraffin. Six-micrometre-thick sections were stained with Mallory’s triple stain and toluidine blue in 1% aqueous solution at pH 1.0 for 5 min (for Mast Cells). RJ was shown to protect the colonic mucosa against the injurious effect of acetic acid. Colitis (colonic damage) was confirmed histomorphometrically as significant increases in the number of mast cells (MC) and colonic erosions in rats with acetic acid-induced colitis. The RJ treatment significantly decreased the number of MC and reduced the area of colonic erosion in the colon of RJ-treated rats compared with rats with untreated colitis. The results suggest that oral treatment with RJ could be used to treat colitis.

Antioxidant characterization of native monofloral Cuban honeys

Five typical Cuban monofloral honeys were analyzed for their in vitro total antioxidant capacity (TAC), phenolic compounds, and ascorbic acid content. Identification and quantification of phenolics were carried out by HPLC-DAD-ESI/MS. Fourteen phenolic compounds could be identified (eight phenolic acids and six flavonoids), including three glycosylated derivatives. Similar contents of total phenolics were found in the different honeys, although they differed in their qualitative profiles. A significant (positive) correlation was found between the results of TAC obtained by parallel FIA-ABTS system and ORAC assay (r=0.9565, p<0.001). Similar correlations were also established between total phenolics and TAC, determined by either the ORAC (r=0.9633; p<or=0.001) or the TEAC assay (r=0.9582; p<or=0.001). Honeys were fractionated by solid-phase extraction into four fractions, and the relative contribution of each fraction to TAC was calculated. Phenolic compounds were significant contributors to the antioxidant capacity of the honeys, but they were not uniquely responsible for it. The antioxidant activity appeared to be a result of the combined activity of a range of compounds including phenolics and other minor components. Ascorbic acid was not detected.

Mitochondria accumulate large amounts of quercetin: prevention of mitochondrial damage and release upon oxidation of the extramitochondrial fraction of the flavonoid

Quercetin uptake in Jurkat cells is extremely rapid and associated with a remarkable accumulation of the flavonoid, dependent on its binding to intracellular components. Cell-associated quercetin is biologically active, quantitatively consumed to promote survival in the presence of reactive species, such as peroxynitrite (ONOO(-)), or reduction of extracellular oxidants via activation of plasma membrane oxidoreductases. In alternative, quercetin is very slowly released upon post-incubation in drug-free medium, an event significantly accelerated by extracellular albumin. Quercetin uptake is also observed in isolated mitochondria, resulting in an enormous accumulation of the flavonoid, consumed under conditions associated with prevention of lipid peroxidation induced by ONOO(-). Interestingly, remarkable quercetin accumulation is also detected in the mitochondria isolated from quercetin-pre-loaded cells, and exposure to either ONOO(-) or extracellular oxidants caused the parallel loss of both the mitochondrial and cytosolic fractions of the flavonoid. In conclusion, Jurkat cells accumulate large amounts of quercetin and even larger amounts of the flavonoid further accumulate in their mitochondria. Intramitochondrial quercetin appears to be functional for prevention of mitochondrial damage as well as for redistribution to the cytosol, when the fraction of the flavonoid therein retained is progressively consumed either by cell-permeant oxidants or by activation of plasma membrane oxidoreductases.

Functional properties of honey, propolis, and royal jelly

Honey, propolis, and royal jelly, products originating in the beehive, are attractive ingredients for healthy foods. Honey has been used since ancient times as part of traditional medicine. Several aspects of this use indicate that it also has functions such as antibacterial, antioxidant, antitumor, anti-inflamatory, antibrowning, and antiviral. Propolis is a resinous substance produced by honeybees. This substance has been used in folk medicine since ancient times, due to its many biological properties to possess, such as antitumor, antioxidant, antimicrobial, anti-inflammatory, and immunomodulatory effects, among others. Royal jelly has been demonstrated to possess numerous functional properties such as antibacterial activity, anti-inflammatory activity, vasodilative and hypotensive activities, disinfectant action, antioxidant activity, antihypercholesterolemic activity, and antitumor activity. Biological activities of honey, propolis, and royal jelly are mainly attributed to the phenolic compounds such as flavonoids. Flavonoids have been reported to exhibit a wide range of biological activities, including antibacterial, antiviral, anti-inflammatory, antiallergic, and vasodilatory actions. In addition, flavonoids inhibit lipid peroxidation, platelet aggregation, capillary permeability and fragility, and the activity of enzyme systems including cyclo-oxygenase and lipoxygenase.

Honey prevents hepatic damage induced by obstruction of the common bile duct

AIM: To examine the possible effects of honey supplementation on hepatic damage due to obstruction of the common bile duct in an experimental rat model.

METHODS: The study was performed with 30 male rats divided into three groups: a sham group, an obstructive jaundice group, and an obstructive jaundice plus honey group. At the end of the study period, the animals were sacrificed, and levels of nitric oxide (NO), and NO synthase (NOS) activities were measured in liver tissues, and levels of adenosine deaminase (ADA) and alanine transaminase (ALT) activities were measured in serum.

RESULTS: Blood ALT and ADA activities were significantly elevated in the jaundice group as compared to those of the sham group. In the obstructive jaundice plus honey group, blood ALT and ADA activities were significantly decreased as compared to those of the jaundice group. In erythrocytes and liver tissues, NO levels were found to be significantly higher in the obstructive jaundice plus honey group compared to those of the sham group. Additionally, NO levels were found to be significantly higher in liver tissues from the animals in the obstructive jaundice plus honey group than those of the jaundice group.

CONCLUSION: Honey was found to be beneficial in the prevention of hepatic damage due to obstruction of the common bile duct.