Artepillin C and phenolic compounds responsible for antimicrobial and antioxidant activity of green propolis andBaccharis dracunculifoliaDC

Modulation of innate immunity related genes resulting in prophylactic antimicrobial and antiviral properties

BACKGROUND

The innate immunity acts during the early phases of infection and its failure in response to a multilayer network of co-infections is cause of immune system dysregulation. Epidemiological SARS-CoV-2 infections data, show that Influenza Virus (FLU-A-B-C) and Respiratory Syncytial Virus (RSV) are co-habiting those respiratory traits. These viruses, especially in children (mostly affected by 'multi-system inflammatory syndrome in children' [MIS-C] and the winter pandemic FLU), in the aged population, and in 'fragile' patients are causing alteration in immune response. Then, bacterial and fungal pathogens are also co-habiting the upper respiratory traits (e.g., Staphylococcus aureus and Candida albicans), thus contributing to morbidity in those COVID-19 affected patients.

METHODS

Liquid chromatography coupled with high-resolution mass spectrometry using the quadrupole orbital ion trap analyser (i.e., UHPLC-Q-Orbitrap HRMS) was adopted to measure the polyphenols content of a new nutraceutical formula (Solution-3). Viral infections with SARS-CoV-2 (EG.5), FLU-A and RSV-A viruses (as performed in BLS3 authorised laboratory) and real time RT-PCR (qPCR) assay were used to test the antiviral action of the nutraceutical formula. Dilution susceptibility tests have been used to estimate the minimum inhibitory and bactericidal concentration (MIC and MBC, respectively) of Solution-3 on a variety of microorganisms belonging to Gram positive/ negative bacteria and fungi. Transcriptomic data analyses and functional genomics (i.e., RNAseq and data mining), coupled to qPCR and ELISA assays have been used to investigate the mechanisms of action of the nutraceutical formula on those processes involved in innate immune response.

RESULTS

Here, we have tested the combination of natural products containing higher amounts of polyphenols (i.e., propolis, Verbascum thapsus L., and Thymus vulgaris L.), together with the inorganic long chain polyphosphates 'polyPs' with antiviral, antibacterial, and antifungal behaviours, against SARS-CoV-2, FLU-A, RSV-A, Gram positive/ negative bacteria and fungi (i.e., Candida albicans). These components synergistically exert an immunomodulatory action by enhancing those processes involved in innate immune response (e.g., cytokines: IFNγ, TNFα, IL-10, IL-6/12; chemokines: CXCL1; antimicrobial peptides: HBD-2, LL-37; complement system: C3).

CONCLUSION

The prophylactic antimicrobial success of this nutraceutical formula against SARS-CoV-2, FLU-A and RSV-A viruses, together with the common bacteria and fungi co-infections as present in human oral cavity, is expected to be valuable.

Hive Products: Composition, Pharmacological Properties, and Therapeutic Applications

Beekeeping provides products with nutraceutical and pharmaceutical characteristics. These products are characterized by abundance of bioactive compounds. For different reasons, honey, royal jelly, propolis, venom, and pollen are beneficial to humans and animals and could be used as therapeutics. The pharmacological action of these products is related to many of their constituents. The main bioactive components of honey include oligosaccharides, methylglyoxal, royal jelly proteins (MRJPs), and phenolics compounds. Royal jelly contains jelleins, royalisin peptides, MRJPs, and derivatives of hydroxy-decenoic acid, particularly 10-hydroxy-2-decenoic acid (10-HDA), which possess antibacterial, anti-inflammatory, immunomodulatory, neuromodulatory, metabolic syndrome-preventing, and anti-aging properties. Propolis has a plethora of activities that are referable to compounds such as caffeic acid phenethyl ester. Peptides found in bee venom include phospholipase A2, apamin, and melittin. In addition to being vitamin-rich, bee pollen also includes unsaturated fatty acids, sterols, and phenolics compounds that express antiatherosclerotic, antidiabetic, and anti-inflammatory properties. Therefore, the constituents of hive products are particular and different. All of these constituents have been investigated for their properties in numerous research studies. This review aims to provide a thorough screening of the bioactive chemicals found in honeybee products and their beneficial biological effects. The manuscript may provide impetus to the branch of unconventional medicine that goes by the name of apitherapy.

In vitro and in vivo burn healing study of standardized propolis: Unveiling its antibacterial, antioxidant and anti-inflammatory actions in relation to its phytochemical profiling

BACKGROUND

Natural propolis has been used since decades owing to its broad-spectrum activities. Burn injuries are a global health problem with negative impacts on communities. Bacterial infections usually accompany burns, which demand implementation of antibiotics. Antibiotics abuse led to emergence of microbial drug resistance resulting in poor treatment outcomes. In such instances, the promising alternative would be natural antimicrobials such as propolis.

OBJECTIVE

Full chemical profiling of propolis and evaluation of in vitro antibacterial, antioxidant and anti-inflammatory activities as well as in vivo burn healing properties.

METHODS

Chemical profiling of propolis was performed using Liquid chromatography (UHPLC/MS-PDA and HPLC-PDA). In vitro assessment was done using Disc Diffusion susceptibility test against Staphylococcus aureus and infected burn wound mice model was used for in vivo assessment. In vitro antioxidant properties of propolis were assessed using DPPH, ABTS and FRAP techniques. The anti-inflammatory effect of propolis was assessed against lipopolysaccharide/interferon-gamma mediated inflammation.

RESULTS

UHPLC/MS-PDA results revealed identification of 71 phytochemicals, mainly flavonoids. Upon flavonoids quantification (HPLC-PDA), Pinocembrin, chrysin and galangin recorded high content 21.58±0.84, 22.73±0.68 and 14.26±0.70 mg/g hydroalcoholic propolis extract, respectively. Propolis showed concentration dependent antibacterial activity in vitro and in vivo burn healing via wound diameter reduction and histopathological analysis without signs of skin irritation in rabbits nor sensitization in guinea pigs. Propolis showed promising antioxidant IC50 values 46.52±1.25 and 11.74±0.26 μg/mL whereas FRAP result was 445.29±29.9 μM TE/mg. Anti-inflammatory experiment results showed significant increase of Toll-like receptor 4 (TLR4), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) mRNA levels. Nitric oxide and iNOS were markedly increased in Griess assay and western blot respectively. However, upon testing propolis against LPS/IFN-γ-mediated inflammation, TLR4, IL-6 and TNF-α expression were downregulated at transcriptional and post-transcriptional levels.

CONCLUSION

Propolis proved to be a promising natural burn healing agent through its antibacterial, antioxidant and anti-inflammatory activities.

Encapsulation of propolis extracted with methylal in the chitosan nanoparticles and its antibacterial and cell cytotoxicity studies

In this study we develop novel type of antibacterial chitosan-propolis NPs to improve theantimicrobial activity against various pathogens. To this aim, we primarily extracted propolis with methylal and ethanol as green solvents and its encapsulation with chitosan NPs. The developed propolis loaded chitosan NPs indicated antimicrobial and anti-biofilm properties against various gram positive and negative. FTIR revealed the successful encapsulation of the propolis extract with Ethanol (PE) and Methylal (PM) into the chitosan nano career matrix. HPLC and GC-MASS also confirmed the presence of flavonoids and phenols compounds of propolis extracted with both solvents. In addition, we confirmed the total phenolic and flavonoid compounds in propolis by calorimetric method of Folin-Ciocalteu and aluminum trichloride complex formation assays, respectively. PE-CH and PM-CH were optimized regarding physicochemical properties such as particle size, zeta potential, and poly dispersity index (PDI) index. DLS and SEM micrographs confirmed a spherical morphology in a range of 360-420 nm with Z potential values of 30-48 mV and PDI of 0.105-0.166 for PE-CH and PM-CH, respectively. The encapsulation efficiency was evaluated using colorimetric analysis, with median values ranging from 90 to 92%. The MIC values within the range of 2 to 230 µg/ml and MBC values between 3 to 346 μg/ml against both gram-positive and negative bacteria. While both PE and PM showed a significant reduction in the number of E. coli, S. aureus, and S. epidermidis, the use of PE-CH and PM-CH led to a statistically significant and greater reduction in number of E. coli, S. aureus, and S. epidermidis strains on the biofilm, pre-formed biofilm and planktonic phases. Besides, the DPPH assay showed significant antioxidant activity for these NPs within the range of 36 to 92%. MTT assay for MHFB-1, HFF, L929, MDF, and MCF-7 cells exhibited statistically significant differences in each other that show the IC50 between 60-160 µg/ml for normal cells and 20 for cancer cells. Finally the present study indicated that both PM and PM-CH greater than PE and PE-CH in which contain high flavonoid and phenolic contents with a high antioxidation potential antioxidant properties, which could be beneficial for cell proliferation and antibiotic and anticancer applications.

Hamamelis virginiana L. extract presents antimicrobial and antibiofilm effects, absence of cytotoxicity, anti-inflammatory action, and potential to fight infections through the nitric oxide production by macrophages

The potential of H. virginiana L. was evaluated against Candida spp. (C. albicans, C. dubliniensis, C. glabrata, C. guilliermondii, C. krusei, and C. tropicalis) and bacteria (Acinetobacter baumannii, Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, Staphylococcus aureus, and Streptococcus mutans). Effect on murine macrophages (RAW 264.7) was also evaluated with respect to cytotoxicity and production of cytokines (IL-1β and TNF-α) and nitric oxide (NO). The most effective concentrations of the extract were determined by microdilution broth. These concentrations were analyzed on biofilms, after 5 min or 24 h exposure. Cytotoxicity was performed by MTT assay and quantification of cytokines and NO by ELISA and Griess reagent, respectively. The extract acted against the planktonic forms and provided significant reductions of all the microbial biofilms; besides, showed no cytotoxic effect, except at 100 mg/mL, after 24 h exposure. There was cytokine production; however, a modulatory effect was observed in groups exposed to lipopolysaccharide (LPS) from E. coli. NO production was similar or higher than the control group. Thus, H. virginiana L. extract showed antimicrobial and antibiofilm effects; absence of cytotoxicity for RAW 264.7; anti-inflammatory action; and potential to fight infections through the NO production.

Food-grade delivery systems of Brazilian propolis from Apis mellifera: From chemical composition to bioactivities in vivo

Brazilian propolis from Apis mellifera is widely studied worldwide due to its unique chemical composition and biological properties, such as antioxidant, antimicrobial, and anti-inflammatory. However, although many countries produce honey, another bee product, the consumption of propolis as a functional ingredient is linked to hydroethanolic extract. Hence, other food uses of propolis still have to be incorporated into food systems. Assuming that propolis is a rich source of flavonoids and is regarded as a food-grade ingredient for food and pharmaceutical applications, this review provides a theoretical and practical basis for optimising the bioactive properties of Brazilian propolis, encompassing the extraction processes and incorporating its bioactive compounds in the delivery systems for food applications. Overall, pharmacotechnical resources can optimise the extraction and enhance the chemical stability of phenolic compounds to ensure the bioactivity of food formulations.

pH-Dependence Cytotoxicity Evaluation of Artepillin C against Tumor Cells

Brazilian green propolis is a well-known product that is consumed globally. Its major component, Artepillin C, showed potential as an antitumor product. This study explored the impact of Artepillin C on fibroblast and glioblastoma cell lines, used as healthy and very aggressive tumor cell lines, respectively. The focus of the study was to evaluate the pH-dependence of Artepillin C cytotoxicity, since tumor cells are known to have a more acidic extracellular microenvironment compared to healthy cells, and Artepillin C was shown to become more lipophilic at lower pH values. Investigations into the pH-dependency of Artepillin C (6.0-7.4), through viability assays and live cell imaging, revealed compelling insights. At pH 6.0, MTT assays showed the pronounced cytotoxic effects of Artepillin C, yielding a notable reduction in cell viability to less than 12% among glioblastoma cells following a 24 h exposure to 100 µM of Artepillin C. Concurrently, LDH assays indicated significant membrane damage, affecting approximately 50% of the total cells under the same conditions. Our Laurdan GP analysis suggests that Artepillin C induces autophagy, and notably, provokes a lipid membrane packing effect, contributing to cell death. These combined results affirm the selective cytotoxicity of Artepillin C within the acidic tumor microenvironment, emphasizing its potential as an effective antitumor agent. Furthermore, our findings suggest that Artepillin C holds promise for potential applications in the realm of anticancer therapies given its pH-dependence cytotoxicity.

A Sustainable Approach for the Valorization of Underutilized Date Fruits

Secondary varieties of date fruits are often discarded because they do not have commercial value. However, their phytochemicals are very similar to those of the primary ones and therefore, they can be valorized as a source of compounds of interest, mainly phenols and dietary fiber. Their chemical composition changes with ripening, so their characterization throughout this process is of great significance. Date fruit samples were harvested at Khalal, Rutab, and Tamer stages, and a mixture of fruits from ornamental date trees was also analyzed. Aqueous and ethanolic extracts were studied for their phenolic composition. In aqueous extracts, phenols decreased with ripening, while in the ethanolic ones having higher phenolic content. Chelidonic acid, a γ-pyrone, was the major compound found in all extracts, but in the ethanolic ones, flavonoids were also present in similar amounts. After purification by adsorption chromatography, all extracts were assayed for their antimicrobial activity. Those from the Tamer stage showed the highest activity, especially against Gram-positive bacteria. The fibrous residues after aqueous and ethanolic extractions were also characterized. Their chemical composition suggested that they can be considered as a good source of prebiotic arabinoxylans and antioxidant fiber, whose antiradical activity correlated with their phenolic content. Date fruits from secondary varieties are promising as a worthwhile starting point for obtaining new value-added products.

Phyto-Inhibitory and Antimicrobial Activity of Brown Propolis from Romania

The objective of this paper was to study the phyto-inhibitory and antimicrobial activity of brown propolis collected from the counties of four regions in Romania. The main physico-chemical and functional properties of 16 samples of propolis from different landforms of geographical regions were determined. Their antimicrobial activities were established against 5 bacterial strains (Pseudomonas fluorescens, Bacillus subtilis, Bacillus cereus, Escherichia coli, and Proteus mirabilis) and 5 fungal strains (Alternaria alternata, Cladosporium cladosporioides, Fusarium oxysporum, Mucor racemosus, and Aspergillus niger). Simultaneously, the phyto-inhibitory effect of propolis samples on different cereals was highlighted: hexaploid bread wheat (Triticum aestivum), maize (Zea mays L.), oats (Avena sativa L.), and barley (Hordeum vulgare L.). Correlations between the antioxidant activity and total flavonoid and phenol content of the propolis samples were identified, respectively, and the statistical analysis highlighted that the diameter of the inhibition zone was influenced by the strain type (bacterial and fungal) and the geographical regions of propolis. Principal component analysis (PCA) indicated that out of seven principal components, only two exhibited > 0.5. Pearson's correlation coefficient showed a low and moderate positive linear relationship between the diameter of the inhibition zone and the flavonoid and phenol concentration of the propolis samples.

Antimicrobial activity in Asterceae: The selected genera characterization and against multidrug resistance bacteria

Plants from the Asteraceae family are widely used as ethno medicines to treatment parasitic, malaria, hematemesis, pruritus, pyretic, anthelmintic, wound healing. The aim of this review is to provide an overview of Asteraceae plants antimicrobial activity. The most relevant results from the published studies are summarized and discussed. The species in genus of Artemisia, Echinacea, Centaurea, Baccharis, and Calendula showed antimicrobial activity. Most of these species are usually used as ethno medicines to treat infection, inflammation, and parasitics. The effective part or component for antimicrobial was essential oil and crude extract, and essential oil attracted more attention. It was also reported that nanoparticles coated with crude extract were effective against multidrug resistant bacteria. For multidrug resistant bacteria study, the species in Armtemisia were the most investigated, and Staphylococcus aureus and Escherichia coli were the most studied multidrug resistant strains. The antimicrobial activity was evaluated mainly based on the results of minimum inhibitory concentration (MIC). Few reports have been reported on minimum bactericide concentration (MBC) and its antibacterial mechanisms. According to the reported study results, some plants in Asteraceae have the potential to be developed as bacteriostatic agents and against multidrug resistant bacteria. However, most studies are still in vitro, further clinical and applied studies are needed.

Repurposing of phyto-ligand molecules from the honey bee products for Alzheimer's disease as novel inhibitors of BACE-1: small molecule bioinformatics strategies as amyloid-based therapy

Alzheimer's disease (AD) is one of the neurodegenerative diseases, manifesting dementia, spatial disorientation, language, cognitive, and functional impairment, mainly affects the elderly population with a growing concern about the financial burden on society. Repurposing can improve the traditional progress of drug design applications and could speed up the identification of innovative remedies for AD. The pursuit of potent anti-BACE-1 drugs for AD treatment has become a pot boiler topic in the recent past and to instigate the design of novel improved inhibitors from the bee products. Drug-likeness characteristics (ADMET: absorption, distribution, metabolism, excretion, and toxicity), docking (AutoDock Vina), simulation (GROMACS), and free energy interaction (MM-PBSA, molecular mechanics Poisson-Boltzmann surface area) analyses were performed to identify the lead candidates from the bee products (500 bioactives from the honey, royal jelly, propolis, bee bread, bee wax, and bee venom) for Alzheimer's disease as novel inhibitors of BACE-1 (beta-site amyloid precursor protein cleaving enzyme (1) receptor using appropriate bioinformatics tools. Forty-four bioactive lead compounds were screened from the bee products through high throughput virtual screening on the basis of their pharmacokinetic and pharmacodynamics characteristics, showing favorable intestinal and oral absorption, bioavailability, blood brain barrier penetration, less skin permeability, and no inhibition of cytochrome P450 inhibitors. The docking score of the forty-four ligand molecules was found to be between -4 and -10.3 kcal/mol, respectively, exhibiting strong binding affinity to BACE1 receptor. The highest binding affinity was observed in the rutin (-10.3 kcal/mol), 3,4-dicaffeoylquinic acid (-9.5 kcal/mol), nemorosone (-9.5 kcal/mol), and luteolin (-8.9 kcal/mol). Furthermore, these compounds demonstrated high total binding energy -73.20 to -105.85 kJ/mol), and low root mean square deviation (0.194-0.202 nm), root mean square fluctuation (0.0985-0.1136 nm), radius of gyration (2.12 nm), number of H-bonds (0.778-5.436), and eigenvector values (2.39-3.54 nm²) in the molecular dynamic simulation, signifying restricted motion of Cα atoms, proper folding and flexibility, and highly stable with compact of the BACE1 receptor with the ligands. Docking and simulation studies concluded that rutin, 3,4-dicaffeoylquinic acid, nemorosone, and luteolin are plausibly used as novel inhibitors of BACE1 to combat AD, but further in-depth experimental investigations are warranted to prove these in silico findings.

Artepillin C Time−Dependently Alleviates Metabolic Syndrome in Obese Mice by Regulating CREB/CRTC2−BMAL1 Signaling

Artepillin C (APC), a cAMP-response element−binding (CREB)/CREB regulated transcription coactivator 2 (CRTC2) inhibitor isolated from Brazilian green propolis, can ameliorate metabolic syndrome in obese mice. Because the sensitivity and responsiveness of the body to the drug depend on the time of day and the circadian clock alignment, the optimal administration time of APC for desired efficacy in treating metabolic syndrome remains unclear. In this study, APC (20 mg/kg) or the vehicle was intraperitoneally injected into obese mice once daily for one or three weeks. The results of the insulin tolerance test, pyruvate tolerance test, and histological and biochemical assays showed that APC could improve whole−body glucose homeostasis and decrease hepatic lipid synthesis following a circadian rhythm. Further exploration of the underlying mechanism revealed that APC may disturb the diurnal oscillations of the expression of brain and muscle ARNT−like protein (BMAL1) in primary hepatocytes and the livers of the study subjects. Moreover, APC could inhibit hepatic BMAL1 expression by blocking the CREB/CRTC2 transcription complex. BMAL1 overexpression in primary hepatocytes or the livers of db/db mice antagonized the inhibitory effect of APC on hepatic lipid metabolism. In conclusion, the chronotherapy of APC may relieve metabolic syndrome in obese mice, and the mechanism behind APC−mediated time−of−day effects on metabolic syndrome were unveiled, thereby providing a foundation for optimized APC treatment from a mechanistic perspective.

Polyphenol Extracts from Sage (Salvia lavandulifolia Vahl) By-Products as Natural Antioxidants for Pasteurised Chilled Yoghurt Sauce

Sage by-product extracts (SE) are a valuable source of phenolic acids and flavonoids for food applications. The objective was to test two SE as antioxidants in pasteurised chilled yoghurt sauces against oxidation. Two SE of different polyphenol total content and profile were selected: SE38 (37.6 mg/g) and SE70 (69.8 mg/g), with salvianic and rosmarinic acid as the main polyphenols, respectively. Four experimental low-fat yoghurt sauces were formulated: untreated; SE70/2 (0.16 g/kg); SE38 (0.3 g/kg); and SE70 (0.3 g/kg). The stability of phenolic acids, microbiological quality (mesophilic bacteria, moulds and yeasts, and L. monocytogenes), and oxidative stability (lipids, colour, and pH) were studied in the sauces after pasteurisation at 70 °C for 30 min (day 0) and stored by refrigeration (day 42). Pasteurisation and further chilling ensured the microbiological quality and inhibition of microbial growth could not be evidenced, although SE70 showed some antimicrobial potential. Both SE showed good properties as antioxidants for yoghurt sauces. This finding was based on two results: (i) their main polyphenols, salvianic and rosmarinic acids, resisted to mild pasteurisation and remained quite stable during shelf life; and (ii) SE improved radical scavenging capacity, delayed primary and secondary lipid oxidation, and increased colour stability, contributing to sauce stabilisation. SE38 had a better antioxidant profile than SE70; therefore, the selection criteria for SE should be based on both quantity and type of polyphenols. Due to their stability and antioxidant properties, sage polyphenols can be used as natural antioxidants for clean-label yoghurt sauces.

Brazilian Propolis Intake Decreases Body Fat Mass and Oxidative Stress in Community-Dwelling Elderly Females: A Randomized Placebo-Controlled Trial

This study aimed to investigate the effects of Brazilian propolis on body fat mass and levels of adiponectin and reactive oxygen species among community-dwelling elderly females. This was a double-blind randomized placebo-controlled trial. Altogether, 78 females aged 66-84 years were randomly assigned to the propolis (PRO; n = 39) or placebo (PLA; n = 39) group. For 12 weeks, the PRO group were given three capsules containing 227 mg of propolis twice a day. Meanwhile, the PLA group were given daily placebo capsules. Of 78 participants, 53 (PLA group: n = 28, PRO group: n = 25) completed the study. Although no changes were observed in absolute or relative fat mass in the PLA group, they showed a significant decline in the PRO group. The level of serum adiponectin in the PLA group did not change, although that of the PRO group significantly increased. The level of d-ROMs in the PLA group significantly increased, whereas that of the PRO group significantly decreased. The serum SOD activity in the PLA group significantly decreased, whereas that of the PRO group tended to increase. These results suggest that propolis supplementation may decrease body fat mass and oxidative stress among community-dwelling elderly females.

Revalorisation of Sage (Salvia lavandulifolia Vahl) By-Product Extracts as a Source of Polyphenol Antioxidants for Novel Jelly Candies

Sage (Salvia lavandulifolia Vahl) aqueous extracts (SE) obtained from distillation by-products were assessed as antioxidants for nutritionally enhanced jelly candies. Two experimental SEs with a different content of phenolic acids and flavonoids were tested: (i) SE38 (37.6 mg/g) and (ii) SE70 (69.8 mg/g), with salvianic and rosmarinic acids as main polyphenols, respectively. Flavour alteration, stability of sage polyphenols, physical quality traits and antioxidant capacity (AC) were studied in strawberry candies formulated without sugars and enriched with SEs at 0.25, 0.50 and 0.75 g/kg. Despite their different quantitative composition, SE38 and SE70 provided similar antioxidant properties, which were dose dependent. Salvianic and rosmarinic acids were stable without degrading to candy processing (up to 80 °C), keeping their antioxidant potential. There were no relevant differences in flavour or physical traits (pH, °Brix and CIELab colour) between untreated and SE-enriched strawberry candies. The addition of 0.75 g SE/kg resulted in relevant increases of candy AC: (i) from 30 to 38 mg GAE/100 g (total phenolics); (ii) from 10 to 17 mg TE/100 g (DPPH^• radical scavenging assay); (iii) from 5 to 13 mg TE/100 g (ABTS^·+ radical scavenging assay); (iv) from 84 to 163 µmol Fe²⁺/100 g (FRAP capacity) and (v) from to 75 to 83% (inhibition of deoxyribose damage). Sage distillation by-products can be revalorised as a source of natural antioxidants to produce healthier candies.

Ethnomedicinal, phytochemical and pharmacological investigations of Baccharis dracunculifolia DC. (ASTERACEAE)

Baccharis dracunculifolia DC (Lamiaceae) (Asteraceae) is found in South America, mainly in Argentina, Brazil, Bolivia, Paraguay and Uruguay. Folk medicine is used as a sedative, hypotensive, bronchodilator, cardiovascular disorders, anti-flu, and also in skin wounds. Considered the main source of green propolis, which increases the pharmacological interest in this species. It is also known as a "benefactor" plant facilitating the development of other plant species around it, being indicated for the recovery of degraded areas. This species has been studied for decades in order to isolate and identify the active principles present in the aerial parts (leaves and flowers) and roots. The present study consists of a review of the scientific literature addressing the ethnobotanical, ethnomedicinal, phytochemical, pharmacological and potential cytotoxic effects of the B. dracunculifolia species. In this survey, we sought to investigate issues related to the botanical and geographic description of the species, the ethnobotanical uses, as well as the phytochemical studies of the essential oil, extracts and green propolis obtained from the aerial parts and roots of B. dracunculifolia. Using high precision analytical tools, numerous compounds have already been isolated and identified from leaves and flowers such as the flavonoids: naringenin, acacetin, dihydrokaempferol, isosakuranetin and kaempferide; phenolic acids: p-coumaric, dihydrocoumaric, ferulic (E)-cinnamic, hydroxycinnamic, gallic, caffeic, and several caffeoylquinic acids derivatives; phenolic acids prenylated: artepillin C, baccharin, drupanin; the glycosides dracuculifosides and the pentacyclic triterpenoids: Baccharis oxide and friedelanol. The predominant class in the essential oil of leaves and flowers are terpenoids comprising oxygenated monoterpenes and sesquiterpenes, highlighting the compounds nerolidol, spathulenol, germacrene D and bicyclogermacrene. These compounds give the species high antimicrobial, antioxidant, antitumor, analgesic, immunomodulatory and antiparasitic potential, making this species a promising herbal medicine. In vitro toxicity assays with B. dracunculifolia extract showed low or no cytotoxicity. However, in vivo analyses with high doses of the aqueous extract resulted in genotoxic effects, which leads us to conclude that the toxicity of this plant is dose-dependent.

Molecular Dereplication and In Vitro and In Silico Pharmacological Evaluation of Coriandrum sativum against Neuroblastoma Cells

The aim of this study was to investigate the cytotoxic activity of the Coriandrum sativum (C. sativum) ethanolic extract (CSEE) in neuroblastoma cells, chemically characterize the compounds present in the CSEE, and predict the molecular interactions and properties of ADME. Thus, after obtaining the CSEE and performing its chemical characterization through dereplication methods using UPLC/DAD-ESI/HRMS/MS, PM6 methods and the SwissADME drug design platform were used in order to predict molecular interactions and ADME properties. The CSEE was tested for 24 h in neuroblastoma cells to the establishment of the IC50 dose. Then, the cell death was evaluated, using annexin-PI, as well as the activity of the effector caspase 3, and the protein and mRNA levels of Bax and Bcl-2 were analyzed by ELISA and RT-PCR, respectively. By UHPLC/DAD/HRMS-MS/MS analysis, the CSEE showed a high content of isocoumarins-dihydrocoriandrin, coriandrin, and coriandrones A and B, as well as nitrogenated compounds (adenine, adenosine, and tryptophan). Flavonoids (apigenin, hyperoside, and rutin), phospholipids (PAF C-16 and LysoPC (16:0)), and acylglicerol were also identified in lower amount as important compounds with antioxidant activity. The in silico approach results showed that the compounds 1 to 6, which are found mostly in the C. sativum extract, obey the “Five Rules” of Lipinski, suggesting a good pharmacokinetic activity of these compounds when administered orally. The IC50 dose of CSEE (20 µg/mL) inhibited cell proliferation and promoted cell death by the accumulation of cleaved caspase-3 and the externalization of phosphatidylserine. Furthermore, CSEE decreased Bcl-2 and increased Bax, both protein and mRNA levels, suggesting an apoptotic mechanism. CSEE presents cytotoxic effects, promoting cell death. In addition to the promising results predicted through the in silico approach for all compounds, the compound 6 showed the best results in relation to stability due to its GAP value.

In vitro comparison between antimicrobial and antibiofilm effects of Green Propolis and Baccharis dracunculifolia against Staphylococcus pseudintermedius isolate

Staphylococcus pseudintermedius is the leading cause of canine pyoderma. Honeybee products are common to treat this and other types of infections. High average annual population loss of bees has been observed. This study evaluated antibacterial and antibiofilm profile of Green Propolis and Baccharis dracunculifolia against S. pseudintermedius and the chemical similarities among both. Ethanolic extracts were produced and chemically characterized. The isolates were subjected to treatment with the extracts in both planktonic and sessile forms. Green propolis minimum inhibitory concentration (MIC) was 0.156 mg / mL, and minimum bactericidal concentration (MBC) was 0.312mg / mL. Baccharis dracunculifolia extract MIC and MBC was 0.312mg / mL and 2.5 mg / mL, respectivelly. Both extracts reduced SD55 formation of biofilm at minimum inhibitory concentration and at 1/8 minimum inhibitory concentration. The results observed in relation to ED99, were similar for both extracts. Besides that, similar chemical indicators between both extracts, including the presence of Artepellin C, suggest that the Baccharis dracunculifolia extract could be an alternative to the Green Propolis extract in the treatment of staph infections.

Antibacterial Activity of Romanian Propolis against Staphylococcus aureus Isolated from Dogs with Superficial Pyoderma: In Vitro Test

Staphylococcal infection treatment in dogs is frequently associated with adverse side effects, high costs, prolonged treatment, and resistant strain selection. Staphylococcus aureus is the most frequently isolated staphylococci in cases of canine superficial pyoderma. The number of Staphylococcus strains to exhibit primary resistance to various drugs in vitro is increasing. Propolis has a diverse chemical composition and well-known therapeutic properties against bacterial infections. The current investigation evaluated in vitro the antimicrobial activity of the commercial allopathic antimicrobials, Romanian propolis ethanolic extracts, against clinical Staphylococcus aureus strains isolated from superficial dermatitis clinical samples in dogs and two reference strains: Staphylococcus aureus ATCC 25923 and Staphylococcus aureus ATCC 43300, as the MSSA and MRSA positive controls, respectively, in western Romania. We used the microdilution broth technique to evaluate the susceptibility profile of the bacteria. The minimum inhibitory concentration (MIC) of the Romanian propolis ethanolic extract ranged from 6 to 10 μg/mL for all isolates, determined by the broth microdilution method. The MICs of ethanolic Romanian propolis extracts had a pronounced antibacterial activity. These results indicate that propolis can potentially be used and recommended for in vivo experiments as a promising therapeutic agent against Staphylococcus aureus infections in superficial dermatitis of dogs.

Biotechnological Processes Simulating the Natural Fermentation Process of Bee Bread and Therapeutic Properties-An Overview

Recent signs of progress in functional foods and nutraceuticals highlighted the favorable impact of bioactive molecules on human health and longevity. As an outcome of the fermentation process, an increasing interest is developed in bee products. Bee bread (BB) is a different product intended for humans and bees, resulting from bee pollen's lactic fermentation in the honeycombs, abundant in polyphenols, nutrients (vitamins and proteins), fatty acids, and minerals. BB conservation is correlated to bacteria metabolites, mainly created by Pseudomonas spp., Lactobacillus spp., and Saccharomyces spp., which give lactic acid bacteria the ability to outperform other microbial groups. Because of enzymatic transformations, the fermentation process increases the content of new compounds. After the fermentation process is finalized, the meaningful content of lactic acid and several metabolites prevent the damage caused by various pathogens that could influence the quality of BB. Over the last few years, there has been an increase in bee pollen fermentation processes to unconventional dietary and functional supplements. The use of the chosen starters improves the bioavailability and digestibility of bioactive substances naturally found in bee pollen. As a consequence of enzymatic changes, the fermentation process enhances BB components and preserves them against loss of characteristics. In this aspect, the present review describes the current biotechnological advancements in the development of BB rich in beneficial components derived from bee pollen fermentation and its use as a food supplement and probiotic product with increased shelf life and multiple health benefits.

Fungal Community Investigation from Propolis Natural Products: Diversity and Antibacterial Activities Evaluation

Discovering new species and interesting bioactive metabolites from customary sources is becoming progressively laborious. Propolis constitutes the largest diversified reserve of microbial constituents in the beehive. However, fungal communities associated with these environments remain insufficiently established. We present the first detailed investigation of the cultivable fungal community associated with Tunisian propolis, and we evaluate its antibacterial properties against pathogenic bacteria. A total of 80 fungal strains were isolated from propolis samples derived from seven different Tunisian locations. The majority of the isolated fungi were classified as Ascomycota (97.5%), and only 2.5% belonged to Basidiomycota. Our collection was clustered into 15 genera, among which Coniochaeta (36.25%), Aspergillus (15%), Penicillium (13.75%), Cladosporium (10%), Fusarium (7.5%), Didymella (5%), and Alternaria (3.75%) were the most common. Evaluation of the antibacterial activity revealed that 25.6% of the total community showed a broad range of antibacterial activity. Particularly, the Penicillium griseofulvum CC8 strain has manifested the strongest inhibitory effects against all the tested bacteria.

Baccharis dracunculifolia DC Hydroalcoholic Extract Improves Intestinal and Hippocampal Inflammation and Decreases Behavioral Changes of Colitis Mice

The hydroalcoholic extract of B. dracunculifolia (HEBD) and its major compound p-coumaric acid were evaluated against the severity of intestinal inflammation and behavioral changes like depressive and anxious behavior in colitis mice. Colitis was induced in Swiss mice by oral dextran sulfate sodium (DSS) administration for five days. The mice received vehicle (10 ml/kg), HEBD (3, 30, or 300 mg/kg), or p-coumaric acid (15 mg/kg) orally, once a day for twelve days. Behavioral tests were performed on the 11^th and 12^th days after the beginning of the treatments. Moreover, the colon, cortex, and hippocampus were collected to analyze oxidative and inflammatory parameters. The treatment with HEBD (300 mg/Kg), but not p-coumaric acid, showed decreased disease activity index (DAI) values compared to the vehicle group and partially preserved the villi architecture and mucin levels. Furthermore, the HEBD increased the antioxidant defenses in the colon and hippocampus and reduced the myeloperoxidase activity and IL-6 levels in the colon from colitis mice. Colitis mice treated with HEBD did not show depressive-like behavior in the tail suspension test. HEBD reduced colon inflammation, while it maintains antioxidant defenses and mucin levels in this tissue. It may reduce neuropsychiatric comorbidities associated with colitis through its antioxidant effects.

Antibacterial, antibiofilm, and cytotoxic activities and chemical compositions of Peruvian propolis in an in vitro oral biofilm

Background: Natural products with antibacterial potential have begun to be tested on biofilm models, bringing us closer to understanding the response generated by the complex microbial ecosystems of the oral cavity. The objective of this study was to evaluate the antibacterial, antibiofilm, and cytotoxic activities and chemical compositions of Peruvian propolis in an in vitro biofilm of Streptococcus gordonii and Fusobacterium nucleatum.

Methods: The experimental work involved a consecutive, in vitro, longitudinal, and double-blinded study design. Propolis samples were collected from 13 different regions of the Peruvian Andes. The disk diffusion method was used for the antimicrobial susceptibility test. The cytotoxic effect of propolis on human gingival fibroblasts was determined by cell viability method using the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay, and the effect of propolis on the biofilm was evaluated by confocal microscopy and polymerase chain reaction (PCR).

Results: The 0.78 mg/mL and 1.563 mg/mL concentrations of the methanolic fraction of the chloroform residue of Oxapampa propolis showed effects on biofilm thickness and the copy numbers of the srtA gene of S. gordonii and the radD gene of F. nucleatum at 48 and 120 hours, and chromatography (UV, λ 280 nm) identified rhamnocitrin, isorhamnetin, apigenin, kaempferol, diosmetin, acacetin, glycerol, and chrysoeriol.

Conclusions: Of the 13 propolis evaluated, it was found that only the methanolic fraction of Oxapampa propolis showed antibacterial and antibiofilm effects without causing damage to human gingival fibroblasts. Likewise, when evaluating the chemical composition of this fraction, eight flavonoids were identified.

Impact of Propolis on Escherichia coli and Bacillus subtilis Based on Total DNA, RNA and Protein Levels

<b>Background and Objectives:</b> Propolis is a natural product derived from plant resins and collected by honeybees to protect the colony against different pathogens. The antimicrobial properties of an ethanolic extract of propolis (EEP) were investigated in this study. <b>Materials and Methods:</b> In the Egyptian Governorate of Giza, F1 carniolan honeybee (<i>Apis mellifera carnica</i> P.) colonies collected propolis in the autumn, spring and summer of 2019-2020. We investigated the antibacterial activity of EEP against Gram-positive <i>B. subtilis</i> and Gram-negative <i>E. coli</i>. Propolis was evaluated and its effects on the amounts of total DNA, RNA and protein in <i>Bacillus subtilis</i> and <i>Escherichia coli</i> were investigated. <b>Results:</b> Propolis inhibited the growth of <i>B. subtilis</i>. At 5% concentration, the inhibition zones were 8.66, 10.66 and 8.52 mm for autumn, spring and summer propolis, respectively, at 10% concentration, they were 19.66, 21.33 and 18.0 mm, respectively. Propolis also inhibited the growth of <i>E. coli</i> at a 5% concentration. The inhibition zones were 3.660, 4.00 and 4.33 mm for autumn, spring and summer propolis, respectively and at 10% concentration, they were 7.65, 8.33 and 7.33 mm, respectively. The inhibition zones were the largest (10.66 and 21.33 mm) for <i>B. subtilis</i> at 5 and 10% propolis, respectively, whereas slightly low inhibition zones (4.0 and 8.33 mm) were observed for <i>E. coli</i> (5 and 10% propolis, respectively) in spring. In <i>E. coli</i> and <i>B. subtilis</i>, propolis inhibited the replication of DNA-dependent RNA polymerase. <b>Conclusion:</b> The study showed that total DNA, RNA and protein levels in <i>B. subtilis</i> were reduced by 40, 15.52 and 52.6%, respectively, whereas those in <i>E. coli</i> were reduced by 12, 15 and 8%, respectively. Furthermore, propolis activity was less effective against Gram-negative bacteria than Gram-positive bacteria.

Processing Technologies for Bee Products: An Overview of Recent Developments and Perspectives

Increased demand for a more balanced, healthy, and safe diet has accelerated studies on natural bee products (including honey, bee bread, bee collected pollen royal jelly, propolis, beeswax, and bee venom) over the past decade. Advanced food processing techniques, such as ultrasonication and microwave and infrared (IR) irradiation, either has gained popularity as alternatives or combined with conventional processing techniques for diverse applications in apiculture products at laboratory or industrial scale. The processing techniques used for each bee products have comprehensively summarized in this review, including drying (traditional drying, infrared drying, microwave-assisted traditional drying or vacuum drying, and low temperature high velocity-assisted fluidized bed drying), storage, extraction, isolation, and identification; the assessment methods related to the quality control of bee products are also fully mentioned. The different processing techniques applied in bee products aim to provide more healthy active ingredients largely and effectively. Furthermore, improved the product quality with a shorter processing time and reduced operational cost are achieved using conventional or emerging processing techniques. This review will increase the positive ratings of the combined new processing techniques according to the needs of the bee products. The importance of the models for process optimization on a large scale is also emphasized in the future.

Contribution of Green Propolis to the Antioxidant, Physical, and Sensory Properties of Fruity Jelly Candies Made with Sugars or Fructans

Enrichment with phenolic compounds is proposed as a strategy to obtain more stable and healthier candy products. A green propolis ethanolic dry extract (PEE) from Braccharis dracunculifolia (Brazilian Alecrim-do Campo) was assessed as an antioxidant in jelly candies. Three levels (0, 0.01, and 0.02% w/w) of PEE were tested in jelly candies alternatively made with two carbohydrate bases (sugars or fructans) and three fruity dyes and flavours (menthe, orange, or strawberry). Propolis polyphenol content (identified by HPLC-MS and quantified by HPLC-DAD/UV-Vis), antioxidant capacity (total phenolics and radical scavenging activity), physical properties (moisture, pH, CIELab colour, and texture profile analysis), and flavour were studied in candies. PEE was rich in polyphenols (>8.7%), including several prenylated p-coumaric, caffeoylquinic and diterpenic acids, and flavonoids, with Artepillin-C (3.4%) as the main bioactive compound. The incorporation of PEE into the hot liquor at 80 °C for 5 min before moulding allowed a good retention of propolis polyphenols in the final product (recovery percentages of up to 97.4% for Artepillin-C). Jelly candies made with sugars or dietetic fructans have poor antioxidant properties, which depend on the dyes and flavours used. Using PEE (at 0.02%) strongly improved the antioxidant capacity (relative increases of up to 465%) of candies without altering the pH, colour, or texture, although off-flavour may appear. Propolis, due to its good antioxidant properties, has potential for use as a functional ingredient in jelly candies.

Stingless Bee Propolis: New Insights for Anticancer Drugs

Natural products are important sources of biomolecules possessing antitumor activity and can be used as anticancer drug prototypes. The rich biodiversity of tropical and subtropical regions of the world provides considerable bioprospecting potential, including the potential of propolis produced by stingless bee species. Investigations of the potential of these products are extremely important, not only for providing a scientific basis for their use as adjuvants for existing drug therapies but also as a source of new and potent anticancer drugs. In this context, this article organizes the main studies describing the anticancer potential of propolis from different species of stingless bees with an emphasis on the chemical compounds, mechanisms of action, and cell death profiles. These mechanisms include apoptotic events; modulation of BAX, BAD, BCL2-L1 (BCL-2 like 1), and BCL-2; depolarization of the mitochondrial membrane; increased caspase-3 activity; poly (ADP-ribose) polymerase (PARP) cleavage; and cell death induction by necroptosis via receptor interacting protein kinase 1 (RIPK1) activation. Additionally, the correlation between compounds with antioxidant and anti-inflammatory potential is demonstrated that help in the prevention of cancer development. In summary, we highlight the important antitumor potential of propolis from stingless bees, but further preclinical and clinical trials are needed to explore the selectivity, efficacy, and safety of propolis.

Daily Brazilian green propolis intake elevates blood artepillin C levels in humans

BACKGROUND

Propolis is a natural product collected by worker bees from a variety of plant species. As a type of propolis, Brazilian green propolis contains a large amount of artepillin C. Artepillin C is a cinnamic acid derivative and has been shown to have a wide variety of biological functions, including anti-inflammatory, antiviral and antitumor activities, in both cell culture and animal models. However, how propolis is digested and absorbed remains to be elucidated. Moreover, blood artepillin C levels after propolis intake have not been shown in human studies.

RESULTS

A randomized, single-blind placebo-controlled study on the effect of Brazilian green propolis on serum artepillin C levels was conducted with healthy volunteers. The participants (n = 133) were randomly allocated in an approximately 2:1 ratio to two groups: propolis (n = 91) and placebo (n = 42). The participants took daily propolis or placebo, and blood tests were performed on day 0 (before propolis intake) and days 1, 3 and 7. Artepillin C was detected in serum in almost all individuals in the propolis groups. No serum artepillin C was detected in the placebo group. Serum artepillin C levels in the female group tended to be higher than those in the male group. In the female group, menstrual status was unrelated to serum artepillin C levels.

CONCLUSION

These results suggested that propolis intake might be more effective for females than for males. © 2021 Society of Chemical Industry.

Antimicrobial activity of Baccharis dracunculifolia DC and its synergistic interaction with nisin against food-related bacteria

The antimicrobial activities of Baccharis dracunculifolia DC essential oil (EO) and hydroalcoholic extract (HE) were evaluated. The EO showed broad antimicrobial activity and its synergistic combination with nisin was tested. Major components of EO were nerolidol, beta-pinene and D-limonene, while artepillin C, rutin and cafeic acid were major phenolics of HE. EO and HE were tested by agar diffusion assay against several strains of bacteria and yeasts, and mixed cultures of bacterial strains. The EO presented the largest spectrum of antimicrobial activity inhibiting all Gram-positive bacteria tested. Yeasts were not inhibited. The effect of EO against mixtures of sensitive and non-sensitive bacteria was tested on milk agar, being the inhibitory effect only observed on mixtures containing susceptible strains. The combination of EO and nisin at ½ MIC was evaluated on the growth curve of Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes and Salmonella Enteritidis during 24 h at 37 °C. The combination EO-nisin was effective and no viable counts of B. cereus, L. monocytogenes and S. Enteritidis was observed, while the individual antimicrobials caused no inhibition. The counts of S. aureus were about 4 log CFU/mL lower in comparison with EO or nisin alone. B. dracunculifolia DC may be a potential source of natural antimicrobials, and its synergistic effect with nisin would reduce the working concentration, minimizing the organoleptic effects associated with this plant antimicrobial.

Experimental Evidence for Therapeutic Potentials of Propolis

Propolis is produced by honeybees from materials collected from plants they visit. It is a resinous material having mixtures of wax and bee enzymes. Propolis is also known as bee glue and used by bees as a building material in their hives, for blocking holes and cracks, repairing the combs and strengthening their thin borders. It has been extensively used since ancient times for different purposes in traditional human healthcare practices. The quality and composition of propolis depend on its geographic location, climatic zone and local flora. The New Zealand and Brazilian green propolis are the two main kinds that have been extensively studied in recent years. Their bioactive components have been found to possess a variety of therapeutic potentials. It was found that Brazilian green propolis improves the cognitive functions of mild cognitive impairments in patients living at high altitude and protects them from neurodegenerative damage through its antioxidant properties. It possesses artepillin C (ARC) as the key component, also known to possess anticancer potential. The New Zealand propolis contains caffeic acid phenethyl ester (CAPE) as the main bioactive with multiple therapeutic potentials. Our lab performed in vitro and in vivo assays on the extracts prepared from New Zealand and Brazilian propolis and their active ingredients. We provided experimental evidence that these extracts possess anticancer, antistress and hypoxia-modulating activities. Furthermore, their conjugation with γCD proved to be more effective. In the present review, we portray the experimental evidence showing that propolis has the potential to be a candidate drug for different ailments and improve the quality of life.

Pharmaceutical Prospects of Bee Products: Special Focus on Anticancer, Antibacterial, Antiviral, and Antiparasitic Properties

Bee products have long been used in traditional healing practices to treat many types of disorders, including cancer and microbial-related diseases. Indeed, several chemical compounds found in bee products have been demonstrated to display anticancer, antibacterial, antiviral, and antiparasitic properties. With the improvement of research tools and in view of recent advances related to bee products, this review aims to provide broad yet detailed insight into the pharmaceutical prospects of bee products such as honey, propolis, bee pollen, royal jelly, bee bread, beeswax, and bee venom, in the domain of cancer and infectious disease management. Available literature confirms the efficacy of these bee products in the alleviation of cancer progression, inhibition of bacterial and viral proliferation, and mitigation of parasitic-related symptoms. With such potentials, bioactive components isolated from the bee products can be used as an alternative approach in the long-run effort to improve humans’ health at a personal and community level.

Beehive Products as Antibacterial Agents: A Review

Honeybees are one of the most marvelous and economically beneficial insects. As pollinators, they play a vital role in every aspect of the ecosystem. Beehive products have been used for thousands of years in many cultures for the treatment of various diseases. Their healing properties have been documented in many religious texts like the Noble Quran and the Holy Bible. Honey, bee venom, propolis, pollen and royal jelly all demonstrated a richness in their bioactive compounds which make them effective against a variety of bacterial strains. Furthermore, many studies showed that honey and bee venom work as powerful antibacterial agents against a wide range of bacteria including life-threatening bacteria. Several reports documented the biological activities of honeybee products but none of them emphasized on the antibacterial activity of all beehive products. Therefore, this review aims to highlight the antibacterial activity of honey, bee venom, propolis, pollen and royal jelly, that are produced by honeybees.

Rosmarinus officinalis L. (rosemary) extract has antibiofilm effect similar to the antifungal nystatin on Candida samples

Candida spp. are naturally opportunistic and can promote infections. These yeasts can form biofilm, after penetration and adhesion to the biotic or abiotic surfaces. Preexisting diseases, treatments with drugs and radiation therapy, medical procedures, and parafunctional habits favor the installation of a fungal infection. Increased resistance to the available antifungals has become a concern. Therefore, alternative methods to control them have been evaluated, including the use of plant substances. In this study, the antibiofilm effect of R. officinalis L. extract was analyzed on C. albicans, C. dubliniensis, C. glabrata, C. krusei, and C. tropicalis. A phytochemical analysis of the extract was performed. Biofilms were formed for 48 h and exposed to the different concentrations of the extract (50, 100, and 200 mg/mL) for 5 min or 24 h. The effect of the plant extract was compared to the antifungal nystatin. Rosmarinus officinalis L. extract was constituted of phenols and flavonoids, highlighting the presence of chlorogenic acid derivatives in its composition. Biofilm reductions were observed after exposure to the plant extract for both periods. The plant extract provided a reduction similar to the antifungal. Thus, R. officinalis L. extract showed antibiofilm effect on Candida spp. comparable to the nystatin.

Artepillin C as an outstanding phenolic compound of Brazilian green propolis for disease treatment: A review on pharmacological aspects

Propolis is a viscous resin consisting of plant material (shoots, flowers, and plant exudates), salivary secretions and waxes produced by Apis mellifera bees. Its popular use aroused the interests of scientific research, which proved to be a potential source of various bioactive substances. The chemical composition of propolis depends on several factors, such as the different types of plant sources collected by bees, geographic origin, and the time of year in which they are produced, but it is known that phenolic represent the main bioactive constituents of propolis. Baccharis dracunculifolia DC (Asteraceae) is the most important botanical source of propolis and a native to southeastern Brazil. It is widely known as the green propolis because of its deep green color. One of its major phenolic acids is artepillin C (Art-C), a diprenyl-p-hydroxycinnamic acid derivative. This review aims to provide a comprehensive summary of the pharmacological effects of Art-C. The limited number of publications on this topic over the past two decades have been collected from databases and summarized. Numerous biological activities have been described for the Art-C, such as gastroprotective, anti-inflammatory, antimicrobial, antioxidant, antitumor. This article describes aspects of occurrence, synthesis, biological activities and pharmacokinetic approaches.

Propolis, Bee Honey, and Their Components Protect against Coronavirus Disease 2019 (COVID-19): A Review of In Silico, In Vitro, and Clinical Studies

Despite the virulence and high fatality of coronavirus disease 2019 (COVID-19), no specific antiviral treatment exists until the current moment. Natural agents with immune-promoting potentials such as bee products are being explored as possible treatments. Bee honey and propolis are rich in bioactive compounds that express strong antimicrobial, bactericidal, antiviral, anti-inflammatory, immunomodulatory, and antioxidant activities. This review examined the literature for the anti-COVID-19 effects of bee honey and propolis, with the aim of optimizing the use of these handy products as prophylactic or adjuvant treatments for people infected with severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). Molecular simulations show that flavonoids in propolis and honey (e.g., rutin, naringin, caffeic acid phenyl ester, luteolin, and artepillin C) may inhibit viral spike fusion in host cells, viral-host interactions that trigger the cytokine storm, and viral replication. Similar to the potent antiviral drug remdesivir, rutin, propolis ethanolic extract, and propolis liposomes inhibited non-structural proteins of SARS-CoV-2 in vitro, and these compounds along with naringin inhibited SARS-CoV-2 infection in Vero E6 cells. Propolis extracts delivered by nanocarriers exhibit better antiviral effects against SARS-CoV-2 than ethanolic extracts. In line, hospitalized COVID-19 patients receiving green Brazilian propolis or a combination of honey and Nigella sativa exhibited earlier viral clearance, symptom recovery, discharge from the hospital as well as less mortality than counterparts receiving standard care alone. Thus, the use of bee products as an adjuvant treatment for COVID-19 may produce beneficial effects. Implications for treatment outcomes and issues to be considered in future studies are discussed.

Capillary Electrophoresis Separation of Artepillin C: Determination in Brazilian Green Propolis

Propolis is important in complementary and alternative medicine having well-known therapeutic applications. Artepillin C, a main component of Brazilian (green) propolis, has attracted great attention for its anticancer action. Consequently, the synthesis of artepillin C has been reported but, due to the limited yield and elevated costs, this biomolecule is largely produced from Brazilian propolis. We report the capillary electrophoresis (CE) separation of artepillin C in Brazilian propolis also comparing the results with those of HPLC-UV-MS. Optimal separation was obtained with a simple buffer constituted of sodium tetraborate 30 mM pH 9.2 and detection at 210 nm. Artepillin C and the polyphenols of propolis were fully separated with a voltage gradient of 30 to 8 kV and a current of 300 μA for a total run of 50 min. The sensitivity of CE-UV was 22 times greater than HPLC-UV and 100 times more than HPLC-MS with also a stronger reduction in the run time and a greater robustness and reproducibility. The development of CE as an effective and reliable method for the analysis of artepillin C is desired as the standardized quality controls are essential before propolis or its biomolecules can be adopted routinely in nutraceuticals, food ingredients and therapeutic applications.

Insights into the mechanisms and kinetics of the hydroperoxyl radical scavenging activity of Artepillin C

Through the single electron transfer mechanism, Artepillin C scavenges the hydroperoxyl radical in water approximately 572 times faster than Trolox.

Propolis ethanolic extract has double-face in vitro effect on the planktonic growth and biofilm formation of some commercial probiotics

This study investigated the in vitro effect of propolis ethanolic extract (PEE) on planktonic growth and biofilm forming abilities of five commercial probiotics (Enterol, Protexin, Normaflore, BioGaia and Linex). Broth microdilution method was used to investigate the susceptibility of the microbes of five commercial probiotics to PEE. Crystal violet assay was used for the quantitative assessment of biofilm formation and mature biofilm eradication tests. Effect of PEE on autoaggregation ability and swarming motility of Normaflore microbes was determined. Planktonic forms of probiotics showed varied susceptibilities with minimal inhibitory concentration values in the range of 100-800 µg/mL of PEE. However, low PEE concentrations significantly enhanced the planktonic growth of Linex and BioGaia microbes. Biofilm studies revealed that Enterol and Protexin were non-biofilm formers, while BioGaia, Linex and Normaflore showed weak biofilms, which were inhibited by 12.5, 25, and 800 µg/mL of PEE, respectively. PEE revealed double-face effect on the biofilms of Normaflore and Linex, which were enhanced at low concentrations of PEE and inhibited at higher concentrations. Interestingly, Normaflore biofilms were shifted from weak to strong biofilms at low PEE concentrations (12.5, 25, and 50 µg/mL). In conclusion, PEE has strain dependent controversial effects on the planktonic growth and biofilm forming ability of the tested probiotics, although high concentrations have inhibitory effect on all of them, low concentrations may have strain dependent prebiotic effect.