Effects of propolis from Brazil and Bulgaria on Salmonella serovars

Propolis shows biological properties such as antibacterial action. This bee product has a complex chemical composition, which depends on the local flora where it is produced. Salmonella serovars are responsible for human diseases that range from localized gastroenteritis to systemic infections. The aim of the present study was to investigate the susceptibility of Salmonella strains, isolated from food and infectious processes, to the antibacterial action of Brazilian and Bulgarian propolis, as well as to determine the behavior of these bacteria, according to the incubation period, in medium plus propolis. Dilution of ethanolic extract of propolis in agar was the used method. Brazilian and Bulgarian propolis showed an antibacterial action against all Salmonella serovars. The minimal inhibitory concentrations (MIC) of propolis were similar, although they were collected in different geographic regions. Salmonella typhimurium, isolated from human infection, was more resistant to propolis than Salmonella enteritidis.

Antibacterial activity of propolis collected in different regions of Brazil

The aim of this study was to investigate the antibacterial activity of propolis samples from Goiás, Paraná and São Paulo States, Brazil, and their flavonoids content. Ethanolic extracts of propolis (EEP) were prepared (30g of propolis in 70% ethanol), and the microorganisms Staphylococcus aureus and Escherichia coli were tested. The methodology employed was agar diffusion using filter paper discs. Ampicillin and tetracycline were used as controls. Antibacterial activity was determined by the reading of inhibition zone diameters (mm) after 24 hours incubation at 37°C. Results demonstrated that EEP inhibited the growth of Staphylococcus aureus but not that of Escherichia coli. Tetracycline and ampicillin showed an efficient action against both bacteria. Flavonoids content was variable, depending on the propolis sample. According to the results, it may be concluded that EEP showed effective action against Gram-positive bacteria, independently on their geographic origin, and a positive correlation between antibacterial activity and flavonoids content

Susceptibility profile of Salmonella against the antibacterial activity of propolis produced in two regions of Brazil

Propolis antibiotic action has been widely investigated. This assay was carried out in order to observe the in vitro antibacterial activity of propolis against Salmonella enteritidis isolated from food and Salmonella typhimurium isolated from human infections. Propolis was collected by Apis mellifera in two regions of Brazil (Mossoró, Rio Grande do Norte State; and Urubici, Santa Catarina State). Both strains survival percentage decreased with time of incubation in Ethanolic Extracts of Propolis (EEP), demonstrating bactericidal effect after 24 hours. It was also observed that EEP from Mossoró was more effective than that from Urubici. The control of the propolis solvent - 70 percent ethanol - was less effective than EEP, showing only a bacteriostatic effect. We can conclude that propolis shows an activity against Gram-negative bacteria that varies according to the geographical region where it was collected by bees.(AU)

Effect of propolis extract on guines pig lung mast cell

The direct effect of ethanolic extract of propolis on guinea pig lung cell suspension containing mast cells, as well as its influence on the histamine release induced by antigen (ovoalbumin 10 mug/ml) and ionophore A 23187 (3 muM) were investigated. Propolis ethanolic extract (300 mug/ml) increased the histamine release in guinea pig lung suspension containing mast cells by a cytotoxic effect. Lower concentrations of propolis had no effect on histamine release. Our results demonstrated that propolis (3, 10, 30, and 100 mug/ml) shows no significant effect on the histamine release induced by ionophore and antigen. Based on these results, we suggest that propolis could directly activate mast cells, promoting inflammatory mediators release by cytotoxic mechanisms, what could be related to allergic processes in propolis sensitive people.(AU)

Seasonal effect of brazilian propolis on seric biochemical variables

Propolis has been the subject of recent scientific investigation due to its bilogical properties, such as antibiotic, antiinflammatory, anesthetic, healing, immunomodulatory, antioxidant, and carcinostatic. The purpose of this study was to analyze the biochemical profile of propolis-treated rats to observe whether propolis might lead to side effects after administration. Evaluation of total protein, glucose, urea, creatinine, triglycerides, cholesterol, and HDL-cholesterol concentrations and determination of aminotransferases (AST and ALT) and lactic dehydrogenase (LDH) in propolis-treated rat serum were performed. The seasonal effect on propolis activity was also analysed, considering the biochemical variables evaluated. The lack of clinically important changes in seric biochemical variables is probably because propolis showed no biological side effects under these conditions. A possible seasonal effect on the biochemical determinations was not observed.

Absence of seasonal effect on the immunomodulatory action of brazilian propolis on natural killer activity

Propolis, a beehive product widely used in folk medicine as an antiinflammatory agent, has been attracting researchers attention to scientifically elucidate its biological properties and therapeutic activities. The aim of this paper was to study the possible effect of propolis on natural killer activity, since propolis immunomodulatory action has been suggested, especially on non-specific immunity. Propolis was produced by africanized honeybees (Apis mellifera L.), collected throughout a whole year, and pooled by season. Hydroalcoholic solutions of propolis were prepared with each pool and administered to rats by gavage over three days. Natural killer activity of non-adherent spleen cells was evaluated by the 51Cr-release cytotoxicity assay against Yac-1 target cells. Our results indicated that the natural killer activity was increased in spleen cells from propolis-treated animals. There were no significant differences related to the seasonal effect on the immunomodulatory action of propolis.

Seasonal effect of brazilian propolis on Candida albicans and Candida tropicalis

Recently, propolis has been attracting the attention of researchers due to various biological activities and therapeutic properties. In Brazil, propolis is produced all year long, so there may be some seasonal variations. This work was carried out in order to compare propolis collected during the four seasons by its in vitro antimicrobial activity on yeast pathogens isolated from human infections. Propolis was produced by africanized honeybees in Botucatu, Säo Paulo State, collected throughout a year and pooled by season. Hydroalcoholic solutions of propolis were prepared with each pool and diluted in agar, using serial concentrations of propolis from each pool. A determination of minimal inhibitory concentration (MIC) was performed. The results show that Candida tropicalis and Candida albicans were susceptible to low concentrations of propolis, the latter showing a higher susceptibility. No differences were seen in relation to seasonal effects in the minimal inhibitory concentration of propolis

Venom production by africanized honeybees (Apis mellifera) and africanized-european hybrids

This study used 15 beehives: five with Africanized queens sisters (Apis mellifera), five with Italian queens sisters (Apis mellifera ligustica), and five with Carniolan queens sisters (Apis meliifera carnica). The queens were fertilized naturally. This experiment was performed in the apiary of the Botucatu School of Veterinary Medicine and Animal Husbandry, UNESP, State of Säo Paulo, Brazil. The following data were obtained from the foraging bees: venom quantity in reservoir, 0.117ñ0.015, 0.139ñ0.020, and 0.147ñ0.024 (mg); venom quantity liberated in extraction apparatus, 0.073ñ0.012, 0.057ñ0.011 and 0.059ñ0.013 (mg); and sting electro stimulus threshold (volts), 10.75ñ1.37, 15.11ñ2.00, and 15.01ñ1.63 for Africanized, Italian x Africanized and Carniolan x Africanized, respectively. The Africanized honeybees possess less venom in reservoir than the European hybrids (Carniolan and Italian). However, they liberated a larger quantity of venom in the extraction apparatus and required lower electro stimulus threshold to promote stinging.

Immunomodulatory action of propolis on macrophage activation

Propolis has been the subject of several recent studies, with the aim of elucidating its biological and pharmacological properties. Propolis has a well-known antimicrobial activity as well as antioxidant, antitumoral, antiinflammatory, and regenerative properties, but literature about its effects on the immunes response in scarce. The goal of this work was to evaluate the propolis effect on macrophage activation by oxygen (H2O2) and nitrogen (NO) metabolite determination. Propolis was produced by africanized honeybees and hydroalcoholic solutions were prepared at different concentrations. Peritoneal macrophages were obtained from male BALB/c mice and culture cells were stimulated in vitro with propolis or interferon-gamma (IFN-gamma). In the in vivo assay, the animals were sacrificed after propolis treatment and cells were stimulated with IFN-gamma. We also investigated the co-stimulant action of propolis associated with IFN-gamma on macrophages. The results show that propolis induces a discreet elevation in H2O2 release and a mild inhibition of NO generation, depending on concentration. Propolis had no co-stimulant activity, diminishing IFN-gamma action on H2O2 and NO production. Data suggest that propolis acts on host non-specific immunity by macrophage activation.

Population analysis of susceptibility to propolis reference strains of Staphylococcus aureus and Escherichia coli

Susceptibility to several ethanolic extracts of propolis (EEP) concentrations was tested with the population analysis technique in reference strains of Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 35218). The results of these tests showed that all bacteria were killed by EEP concentrations approximately equal or higher (2.0 per cent v/v - S. aureus, 10.0 per cent v/v - E. coli) than the respective minimal inhibitory concentrations (MIC). Regarding the susceptibility to propolis, there was a homogeneity of data with the respective time kill curves showing a clear bactericidal effect during 6 to 9 h of exposition.

Efeito antimicrobiano in vitro da própolis / In vitro antimicrobial effect of propolis

The aim of this study was to observe the in vitro antimicrobial effect of propolis upon different microorganisms isolated from infectious processes of animals. The result showed total inhibition (100 per cent) on the growth of the following microorganisms where the number between parentheses means the total of samples being tested: Staphylococcus aureus (57), Prototheca zopfii (15), Corynebacterium bovis (10), Candida albicans (7), Geothricum candidum (95), Enterobacter aerogenes (4). Other microorganisms in test were: Escherichia coli (n=43, 91 per cent), Streptococcus agalactiae (n=44, 90 per cent), Klebsiella pneumoniae (n=13, 87.5 per cent), Pseudomonas aeruginosa (n=7, 85.7 per cent) and Salmonella sp (n=19, 81.3 per cent)

Prototheca zopffi como agente de mastite bovina: clínica e terapêutica / Prototheca zopffi as agent of bovine mastitis: clinics and therapeutics

It was described for the first time in Brazil the involvement of Prototheca alga in bovine mastitis. Treatment with propolis in dimetilsulfoxide (DMSO) resulted in clinical and microbiological cure of 84,8 per cent of treated teats

Serum biochemical determinations of propolis-treated rats

Ethanolic extracts of the bee glue, a resinous substance collected by honeybees called propolis, have been widely used in folk medicine since ancient times. Antibacterial, antifungal and thus antiseptic properties may represent the basis for the historical and present use of these extracts in dermatology, against inflammatory conditions and common colds. This work was carried out in order to verify possible biochemical alterations in some seric parameters of propolis-treated rats. It was shown that propolis possesses an antioxidant property and its administration did not affect either amylase and alanine transaminase activities or total protein concentration.

In vitro activity of propolis against bacterial and yeast pathogens isolated from human infections

The in vitro activity of propolis against 118 Staphylococcus aureus, 108 Escherichia coli, 60 Salmonella typhimurium, 50 Candida albicans, 23 Candida parapsilosis, 19 Candida tropicalis and 14 Candida guilliermondii isolated from human infections was studied by the agar dilution method. Among the bacteria, the Gram-negative were the least susceptible organisms showing minimal inhibitory concentration (MIC) for 90 per cent of the strains tested ranging from 22.5 mg/ml - 10,2 per cent, 23.1 mg/ml - 10.5 per cent V/V. The MIC's for Candida ranged from 0.80 mg/ml to > 11 mg/ml (0.40 per cent V/V to>5.0 per cent V/V) the strains of C. parapsilosis being the least susceptible. The relative order of susceptibility among all isolates,was: S.aureus > C.tropicalis > C.albicans > C.guilliermondii > C.parapsilosis > S.typhimurium > E.coli.