Evaluation of the polyphenolic profile of native Ecuadorian stingless bee honeys (Tribe: Meliponini) and their antibiofilm activity on susceptible and multidrug-resistant pathogens: An exploratory analysis.

Biofilms are associated with infections that are resistant to conventional therapies, contributing to the antimicrobial resistance crisis. The need for alternative approaches against biofilms is well-known. Although natural products like stingless bee honeys (tribe: Meliponini) constitute an alternative treatment, much is still unknown. Our main goal was to evaluate the antibiofilm activity of stingless bee honey samples against multidrug-resistant (MDR) pathogens through biomass assays, fluorescence (cell count and viability), and scanning electron (structural composition) microscopy. We analyzed thirty-five honey samples at 15% (v/v) produced by ten different stingless bee species (Cephalotrigona sp., Melipona sp., M. cramptoni, M. fuscopilosa, M. grandis, M. indecisa, M. mimetica, M. nigrifacies, Scaptotrigona problanca, and Tetragonisca angustula) from five provinces of Ecuador (Tungurahua, Pastaza, El Oro, Los Ríos, and Loja) against 24-h biofilms of Staphylococcus aureus, Klebsiella pneumoniae, Candida albicans, and Candida tropicalis. The present honey set belonged to our previous study, where the samples were collected in 2018-2019 and their physicochemical parameters, chemical composition, mineral elements, and minimal inhibitory concentration (MIC) were screened. However, the polyphenolic profile and their antibiofilm activity on susceptible and multidrug-resistant pathogens were still unknown. According to polyphenolic profile of the honey samples, significant differences were observed according to their geographical origin in terms of the qualitative profiles. The five best honey samples (OR24.1, LR34, LO40, LO48, and LO53) belonging to S. problanca, Melipona sp., and M. indecisa were selected for further analysis due to their high biomass reduction values, identification of the stingless bee specimens, and previously reported physicochemical parameters. This subset of honey samples showed a range of 63-80% biofilm inhibition through biomass assays. Fluorescence microscopy (FM) analysis evidenced statistical log reduction in the cell count of honey-treated samples in all pathogens (P <0.05), except for S. aureus ATCC 25923. Concerning cell viability, C. tropicalis, K. pneumoniae ATCC 33495, and K. pneumoniae KPC significantly decreased (P <0.01) by 21.67, 25.69, and 45.62%, respectively. Finally, scanning electron microscopy (SEM) analysis demonstrated structural biofilm disruption through cell morphological parameters (such as area, size, and form). In relation to their polyphenolic profile, medioresinol was only found in the honey of Loja, while scopoletin, kaempferol, and quercetin were only identified in honey of Los Rios, and dihydrocaffeic and dihydroxyphenylacetic acids were only detected in honey of El Oro. All the five honey samples showed dihydrocoumaroylhexose, luteolin, and kaempferol rutinoside. To the authors' best knowledge, this is the first study to analyze stingless bees honey-treated biofilms of susceptible and/or MDR strains of S. aureus, K. pneumoniae, and Candida species.

Exploring the Chemistry of Ocimum Species under Specific Extractions and Chromatographic Methods: A Systematic Review.

Ocimum is considered the largest genus in the Lamiacea family. The genus includes basil, a group of aromatic plants with a wide range of culinary uses that nowadays draws attention for its medicinal and pharmaceutical potential. This systematic review intends to explore the chemical composition of nonessential oils and their variation across different Ocimum species. Moreover, we aimed to identify the state of knowledge regarding the molecular space in this genus as well as the different methods of extraction/identification and geographical location. Seventy-nine eligible articles were selected for the final analysis, from which we extracted more than 300 molecules. We found that the countries with the highest number of studies into Ocimum species are India, Nigeria, Brazil, and Egypt. However, from all known species of Ocimum, only 12 were found to have an extensive chemical characterization, particularly Ocimum basilicum and Ocimum tenuiflorum. Our study focused especially on alcoholic, hydroalcoholic, and water extracts, in which the main techniques for compound identifications are GC-MS, LC-MS, and LC-UV. Across the compiled molecules, we found a wide variety of compounds, especially flavonoids, phenolic acids, and terpenoids, suggesting that this genus could be a very useful source of possible bioactive compounds. The information collected in this review also emphasizes the huge gap between the vast number of Ocimum species discovered and the number of studies in each of them that determined the chemical characterization.

Influence of Altitudes and Development Stages on the Chemical Composition, Antioxidant, and Antimicrobial Capacity of the Wild Andean Blueberry (Vaccinium floribundum Kunth).

The chemical composition and biological capacities of berries depend on environmental parameters, maturity, and location. The Andean blueberry (Vaccinium floribundum Kunth), also known as mortiño, presents a unique combination of several phytochemicals, which play a synergistic role in its characterization as a functional food. We aimed to expose the possible variations that exist in the profile of the phenolic compounds as well as the antioxidant and antimicrobial capacity of the wild Andean blueberry with respect to three ripeness stages and two different altitudes. We found that polyphenols are the predominant compounds in the berry during the early ripeness stage and are the main bioactive compounds that give rise to the antioxidant capacity and inhibition effect on the growth of gram-positive and gram-negative bacteria. Moreover, the accumulation of ascorbic acid, free amino acids, and anthocyanins increases as the ripening process progresses, and they were the main bioactive compounds in the ripe berry. The latter compounds influence the production of the typical bluish or reddish coloration of ripe blueberries. In addition, it was determined that environmental conditions at high altitudes could have a positive influence in all cases. Overall, our data provide evidence regarding the high functional value of the wild Andean blueberry.

Healthy Photosynthetic Mechanism Suggests ISR Elicited by Bacillus spp. in Capsicum chinense Plants Infected with PepGMV.

The aim of this study was to evaluate the effect of inoculation with Bacillus spp. isolates on the photosynthetic apparatus of Capsicum chinense plants infected with PepGMV. In vitro and greenhouse experiments were performed to evaluate whether the inoculation improved plants' performance through the increase in photosynthetic efficiency to control PepGMV. The results showed that despite PepGMV infection, the plants inoculated with some isolates of Bacillus spp. had a healthy photosynthetic mechanism, as the photochemical parameters and gas exchange increased. The maximum photochemical quantum yield of PSII (Fv/Fm) of plants with PepGMV and inoculated with Bacillus isolates (M9, K46, and K47) increased (7.85, 7.09, and 7.77%, respectively) with respect to uninoculated controls. In inoculated plants, the CO2 assimilation rate increased and the transpiration rate decreased, therefore indicating an increased water use efficiency. This effect was reflected by the less severe symptoms caused by PepGMV in the plants obtained from seeds inoculated with different Bacillus spp. Plants inoculated with K47 isolates showed an increase in fruit yield and quality. This study suggests that it is possible to protect, at the greenhouse level, C. chinense plants from PepGMV through selected rhizobacteria inoculation.

Bioactive compounds, phenolic profile, antioxidant capacity and effectiveness against lipid peroxidation of cell membranes of Mauritia flexuosa L. fruit extracts from three biomes in the Ecuadorian Amazon.

The bioactive compounds, total antioxidant capacity and protective effect against lipid oxidative damage of red blood cell (RBC) membranes of Mauritia flexuosa L. extracts from three altitude levels (low, middle and high zones) were analyzed. The identification of the main polyphenols in the fruit was performed using High Performance Liquid Chromatography/Electrospray Ionization Tandem Mass Spectrometry analysis, while High-Performance Liquid Chromatography - Diode Array Detector was applied for the vitamin C and carotenoid analysis. The ability of the extracts (methanolic, free polyphenols and bound polyphenols) to protect RBC membranes against oxidative destruction was assessed utilizing the thiobarbituric acid reactive substance assay (TBARS) assay. Among the 14 phenolic compounds identified, quercetin glycosides were the most predominant ones. The fruit from the middle altitude zone showed higher vitamin C and lutein contents than those from the low and high areas, whilst higher values of ß-Carotene were obtained in M. flexuosa L. from the low zone. The contents of flavonoids and total polyphenols were lower in fruit from the low zone, whilst the fruit from the middle zone had the highest values. Similar results were observed in the results of the antioxidant capacity assays. However, a significant difference was not found in the protective effect of the extracts from the three altitude zones against lipid peroxidation in RBC membranes.

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.

Pechiche (Vitex Cymosa Berteo ex Speng), a Nontraditional Fruit from Ecuador, is a Dietary Source of Phenolic Acids and Nutrient Minerals, in Addition to Efficiently Counteracting the Oxidative-Induced Damage in Human Dermal Fibroblasts.

Pechiche fruits (Vitex cymosa Berteo ex Speng) from Ecuador were studied to determine their phenolic acid profile, nutrient minerals and capacity to protect primary human dermal fibroblasts (HDFa) against oxidative-induced damage. Up to five phenolic acids were identified, with homovanillic acid as the main one. Vitamin C, ß-carotene and lutein were also determined. Phosphorus and potassium were the main macrominerals, while iron was the principal micromineral. HDFa were preincubated with a crude pechiche extract (PCext) and then subjected to oxidative stress. The activity of five antioxidant enzymes, intracellular reactive oxygen species (ROS) and ATP levels and lipid peroxidation and protein oxidation were used as markers of oxidative damage. Preincubation with PCext for 24 h allowed for the significant reduction of intracellular ROS levels, improved the intracellular ATP levels and protected lipids and proteins against oxidative damage (p 0.05). Additionally, preincubation with PCext was also able to significantly (p < 0.05) improve the activity of the antioxidant enzymes catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase and glutathione transferase, compared to the stressed group without pretreatment. The results obtained in this study suggest the potential of pechiche as a source of bioactive compounds, as well as its beneficial effect against oxidative stress.

Bioactive compounds and antioxidant capacity of Chuquiraga jussieui J.F.Gmel from the highlands of Ecuador.

Chuquiraga jussieui J.F.Gmel is grown between 3000 and 5000 meters above sea level throughout the Andean region of Ecuador and used by the indigenous populations of the Andes for medicinal purposes. Here, we determined the total phenolic, flavonoids, vitamin C and carotenoids content of the leaves and flowers of Ch. jussieui J.F.Gmel from different highlands of Ecuador as well as the capacity of a crude methanolic extract from the both parts of the plant to scavenge free radicals and protect red blood cell membranes from lipid oxidation. The leaves showed a high bioactive compound content in comparison to the flowers. The crude extract from the leaves proved to be more effective than the flowers in reducing iron and scavenging the DPPH, O2- and H2O2 radicals, as well as in protecting cellular membrane against lipid oxidation, demonstrating that Ch. jussieui J.F.Gmel represents an important source of bioactive compounds with relevant healthy properties.

Chemical Composition and Antioxidant Activity of the Main Fruits Consumed in the Western Coastal Region of Ecuador as a Source of Health-Promoting Compounds.

We studied 19 different tropical fruits traditionally consumed in the coastal lowlands of Ecuador to determine their chemical composition and antioxidant activity. Carambola (Averrhoa carambola L.) had the highest total phenolic, flavonoid, and total antioxidant capacity values, whereas guava fruits (Psidium guajava L.) had the highest vitamin C values. The main organic acids identified were lactic, citric, and acetic acids, and the highest amount of lactic acid was found in soursop fruits (Annona muricata L.), whereas Ecuadorian ivory palm (Phytelephas aequatorialis Spruce) and guava fruits had the highest acetic acid content. Guava also had the highest citric acid content; the highest concentration of oxalic acid was found in carambola. In terms of sugar content, giant granadilla (Passiflora quadrangularis L.) had the highest values of glucose, and red mombin (Spondias mombin L.) had the largest values for fructose and guava for sucrose. Chili pepper (Capsicum chinense Jacq) proved to be the main source of carotenoids, lutein, and ß-carotene, anthocyanins, and vitamin C. The results here increase our knowledge regarding the composition of the main fruits consumed on the west coast of Ecuador to facilitate recommendations as potential sources of health-promoting compounds.

Chemical Composition and Antioxidant Activity of the Main Fruits, Tubers and Legumes Traditionally Consumed in the Andean Regions of Ecuador as a Source of Health-Promoting Compounds.

Thirteen fruits, eight legumes and three tubers consumed in the Andean regions of Ecuador were studied to determine their bioactive compounds, organic acids, sugars content, total antioxidant capacity, as well as to determine which among them showed the greatest contribution in terms of antioxidant activity and which compounds contributed to it. Among fruits, taxo fruits (Passiflora mollissima (Kunth) L.H. Bailey) presented the highest values of total phenolic, carotene content, and total antioxidant capacity. The ají ratón (Capsicum chinense Jacq) showed the highest content of vitamin C. Taxo showed the highest content of ß carotene, whilst lycopene was identified only in guayaba fruits (Psidium guajava L.) and ají ratón was the principal source of lutein. In legumes, chocho perla (Lupinus mutabilis Sweet) showed the highest values for both total phenolic and flavonoid content, whilst frejol negro (Phaseolus vulgaris L.) and frejol canario (Vigna unguiculata (L.) Walp) showed the highest values for FRAP and DPPH assay, respectively. Between tubers, the jícama (Smallanthus sonchifolius (Poepp.) H. Rob.) had the majors values in terms of total phenolic, flavonoid content, and total antioxidant capacity. In terms of total antioxidant capacity, taxo fruits have the highest contribution in terms of total antioxidant capacity, whilst the dendogram shown the occurrence of five distinct groups in which taxo was located in the first largest group. Our data contributing towards gaining better knowledge about the Andean Ecuadorian diet and the composition of Andean food in order to estimate dietary intakes of health-promoting components.

Anti-inflammatory effect of the medicinal herbal mixture infusion, Horchata, from southern Ecuador against LPS-induced cytotoxic damage in RAW 264.7 macrophages.

The phytochemical composition and the antioxidant and anti-inflammatory activities of a mixture of 23 plants, named Horchata, traditionally consumed in Ecuador, have been evaluated. The study was carried out using the hydroalcoholic extract (HHext) and infusion (IHext) of the horchata plant mixture. It was verified that thermal treatment affected the contents of vitamin C and carotenoids, but hardly those of polyphenols, which would be the main bioactive compounds in the infusion, the common form of preparation of horchata for consumption. Among phenolic compounds, caffeoylquinic acids, flavones and flavonols (mostly quercetin glycosides) were prominent. Both HHext and IHext extracts managed to protect RAW 264.7 macrophages against LPS-induced cytotoxic damage, increasing the levels of endogenous antioxidant enzymes and modulating the production of pro-inflammatory and anti-inflammatory cytokines. Greater protective effects were obtained for HHext compared to IHext, which was in agreement with its higher content of phenolic compounds favoured by a more efficient extraction in the hydroalcoholic medium. Nonetheless, the infusion still maintained a significant antioxidant and anti-inflammatory activity, which would support the protective effects on health traditionally attributed to its consumption by the population.

Comparison of the Antimicrobial Activities of Four Honeys From Three Countries (New Zealand, Cuba, and Kenya).

Skin and chronic wound infections are an increasing and urgent health problem worldwide. Their management is difficult and the development of antibiotic resistance by both planktonic and biofilm-associated bacteria necessitates the use of alternative treatments. The purpose of this study was to compare the antimicrobial activity of four honeys from different floral and geographical origins: Melipona beecheii honey (Cuba) and three Apis mellifera honeys [Manuka honey (New Zealand), A. mellifera honey (Cuba), and African honey (Kenya)]. The physicochemical parameters were within the ranges reported for these honeys and M. beecheii honey stood out due to its acidic character. An agar incorporation technique was used to determine the minimum active dilution of each honey against 52 clinical isolates (34 Gram-positive, 17 Gram-negative, and 1 Candida albicans). The antibiofilm activity of honeys was tested by assessing their ability to inhibit biofilm formation and to disrupt preformed biofilms. Overall, M. beecheii honey had the highest antimicrobial and antibiofilm activity, although a marked disruption in preformed biofilms was shared by all tested honeys. Structural changes induced by M. beecheii honey on Staphylococcus aureus and Pseudomonas aeruginosa cells were observed by transmission electron microscopy suggesting that this honey has a potent antimicrobial action and may be an excellent candidate for the development of topical preparations for the treatment of infected wounds.

Guava (Psidium guajava L. cv. Red Suprema) Crude Extract Protect Human Dermal Fibroblasts against Cytotoxic Damage Mediated by Oxidative Stress.

We analyzed guava fruits (Psidium guajava L. cv. Red Suprema) from Cuba to determine their chemical composition, total antioxidant capacity, as well as their protective effect against oxidative damage using an in vitro model of human dermal fibroblasts. The guava fruit is a natural source of bioactive compounds, such as polyphenols, vitamin C, folates and beta carotenes with proven health benefits. Human dermal fibroblasts were pre-incubated with different concentrations of guava crude extract and then subjected to oxidative stress using the AAPH stressor. The number of apoptotic and dead cells, as well as the markers of oxidative damage such as lipid and protein oxidation significantly decreased when cells were pre-incubated with guava crude extract and then exposed to the stressor. The activity of antioxidant enzymes also improved when cells were pre-incubated with guava crude extract in comparison to cells subjected to stress without prior pre-incubation with the guava extract. The results obtained in this study highlight the health benefits of guava regarding oxidative stress, proving it to be an important source of bioactive compounds associated with important biological properties.

The protective effect of acerola (Malpighia emarginata) against oxidative damage in human dermal fibroblasts through the improvement of antioxidant enzyme activity and mitochondrial functionality.

Acerola fruits (Malpighia emarginata DC.) from the central region of Cuba were analyzed to determine their chemical composition and protective capacity against oxidative damage using an in vitro human dermal fibroblast (HDFa) model. The chemical composition analyses showed a high content of vitamin C, total polyphenols, ß-carotene and folates in the acerola fruit. From the HPLC-DAD/ESI-MSn analyses, two anthocyanins (cyanidin 3-O-rhamnoside and pelargonidin 3-O-rhamnoside), three hydroxycinnamoyl derivatives (caffeoyl hexoside, dihydrocaffeoylquinic acid and coumaroyl hexoside) and fifteen flavonols (mostly glycosylated forms of quercetin and kaempferol) were detected. HDFa were pre-incubated with an acerola crude extract (ACExt) and subsequently subjected to oxidative stress induced by AAPH. Apoptosis, intracellular ROS and the biomarkers of lipid and protein oxidation significantly increased after inducing stress, while the activities of the antioxidant enzyme catalase and superoxide dismutase and mitochondrial functionality were markedly affected. However, ACExt was able to protect against oxidative damage through decreasing apoptosis, intracellular ROS levels and lipid and protein damage, besides improving antioxidant enzyme activities and mitochondrial functionality. The obtained results support acerola fruits as relevant sources of functional compounds with promising effects on human health.

Influence of Botanical Origin and Chemical Composition on the Protective Effect against Oxidative Damage and the Capacity to Reduce In Vitro Bacterial Biofilms of Monofloral Honeys from the Andean Region of Ecuador.

Three types of monofloral honey from the Andean regions of Ecuador (Avocado, Eucalyptus, and Rapeseed honey) were analyzed to determine their floral origin, physicochemical parameters, chemical composition, antioxidant capacity, and their capacity to reduce in vitro bacterial biofilms. The chemical composition varied considerably depending on floral origin. The highest values of bioactive compounds were found in Avocado honey, classified as dark amber in color, while the lowest values were found in Eucalyptus honey followed by Rapeseed honey, both classified as extra light amber. When compared to Eucalyptus and Rapeseed honey, Avocado honey showed a more effective superoxide scavenging activity, chelating metal ions capacity, and a higher ability to protect human erythrocyte membranes against lipid peroxidation. For antimicrobial activity, the hydrogen peroxide content and the capacity to inhibit the biofilm formation, and to remove preformed biofilm from Staphylococcus aureus and Klebsiella pneumoniae was determined. Avocado honey showed the highest values of hydrogen peroxide content, as well as the highest capacity to reduce in vitro bacterial biofilms. A correlation between color vs. phenolics content vs. superoxide scavenging activity vs. chelating metal ions capacity, and the capacity to protect human erythrocyte membranes against lipid peroxidation was found.

[Multidisciplinary approach of Clostridium difficile infection]. / Abordaje multidisciplinario de la infección por Clostridium difficile.

Clostridium difficile is the most common cause of infectious diarrhea in adults healthcare institutions. Recent studies have shown an increase in the incidence, severity and recurrence of C. difficile infection (CDI). Factors associated with the patient and medical care provided contribute to establishing colonization and, in some cases, subsequent progression to symptomatic disease. The availability of new microbiological techniques has contributed greatly to improving care for these patients. A diagnostic algorithm is provided for cases in which CDI is suspected based on current evidence regarding the effectiveness of microbiological and radiological methods. In cases in which CDI is confirmed, the first and most effective measure is the withdrawal of any antibiotic treatment the patient is receiving, if possible. The antimicrobial treatment of CDI is based on three classic agents: metronidazole, vancomycin and teicoplanin, along with the recent addition of fidaxomicin. Patients presenting serious symptoms, in addition to appropriate support and monitoring measures, may require surgical treatment. Infection prevention and control strategies can interrupt the transmission mechanism. This manuscript reviews current evidence on the approach of this entity from a multidisciplinary point of view.

Radical-scavenging activity, protective effect against lipid peroxidation and mineral contents of monofloral Cuban honeys.

Several monofloral Cuban honeys were analyzed to determine their free radical-scavenging activity and from this the total antioxidant content was estimated. The protective effect against lipid peroxidation in an in vitro model of rat liver homogenates was evaluated and, lastly, the mineral content of the honeys, which can be related to the maintenance of intracellular oxidative balance, was determined. The scavenging capacities against hydroxyl and superoxide radicals were determined using the spin-trapping technique and the hypoxanthine/xanthine oxidase assay, respectively. Lipid peroxidation was evaluated through the production of TBARS and hydroperoxides. All honeys tested showed potential antioxidant activity with Linen vine displaying the highest scavenging capacity towards the DPPH, hydroxyl and superoxide radicals, while the least efficient was Christmas vine honey. Honeys also inhibited, in a concentration-dependent mode, lipid peroxidation in rat liver homogenates, with Linen vine resulting the best while the least effective was Christmas vine honey. The ability to scavenge free radicals and protect against lipid peroxidation may contribute to the ability of certain Cuban honeys to help in preventing/reducing some inflammatory diseases in which oxidative stress is involved. A total of eight minerals were identified and quantified as follows: cadmium, chromium, copper, nickel, iron, manganese, lead, and zinc. Minerals found in higher concentrations were iron, zinc and manganese.

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

Antioxidant and antimicrobial capacity of several monofloral Cuban honeys and their correlation with color, polyphenol content and other chemical compounds.

Several monofloral Cuban honeys were analyzed to determine their total phenolic, flavonoid, ascorbic acid, amino acid, protein and carotenoid contents as well as their radical-scavenging activity and antimicrobial capacities. The total phenolic, flavonoid and carotenoid contents varied considerably, and the highest values were obtained for Linen vine (Govania polygama (Jack) Urb) honey, which is classified as an amber honey. The highest amino acid content was found in Morning glory (Ipomoea triloba L.) while Liven vine had the highest protein content. Similarly Linen vine honey had the highest antioxidant activity while the lowest was found in Christmas vine (Turbina corymbosa (L.) Raf). Ascorbic acid was absent. Hydroxyl radical formation was studied by EPR and spin trapping, and it was found in all honeys tested. The antimicrobial activity was screened using two Gram-positive and Gram-negative bacteria. S. aureus was the most sensitive microorganism while Pseudomonas aeruginosa presented higher minimum active dilution values. Bacillus subtilis and Escherichia coli were both moderately sensitive to honey antimicrobial activity. A correlation between radical-scavenging activity and total phenolic content was found. Correlation existed also between color vs phenolics content, vs flavonoid content or between phenolic vs flavonoid.