Brazilian Propolis: Seasonal Variation of the Prenylated p-Coumaric Acids and Antimicrobial Activity

Brazilian green propolis, which is used in food and beverages to improve health and to prevent diseases, demostrates antioxidant, antimutagenic, and antimicrobial activities. Most biological activities are thought to be related to the high levels of drupanin, artepillin C, and baccharin, which are compounds also present in Baccharis dracunculifolia D.C. (Asteraceae). Since propolis chemical composition depends on the region and the period of collection, as well as its plant origin, the effect of seasonal variation on the both content of prenylated p-coumaric acids and in vitro antimicrobial activity of Brazilian propolis from four different sites, was performed. The results showed that MIC values ranged from 100 to 300 mu g/mL against both Staphylococcus aureus and Kocuria rhizophila, while none of the propolis samples was active against Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. HPLC analysis showed that the content of drupanin, artepillin C, and baccharin varied throughout the year, as well as among the different study sites. Also, it is suggested that Baccharis dracunculifolia is the main botanical source of Brazilian propolis in sites I and 2, while in sites 3 and 4, other plant species are also used by bees to produce propolis. All the evaluated propolis samples exhibited similar antibacterial activity, but different contents of prenylated p-coumaric acids throughout the year.

Molecular dynamics, density functional, ADMET predictions, virtual screening, and molecular interaction field studies for identification and evaluation of novel potential CDK2 inhibitors in cancer therapy

In this work, we have used molecular dynamics, density functional theory, virtual screening, ADMET predictions, and molecular interaction field studies to design and propose eight novel potential inhibitors of CDK2. The eight molecules proposed showed interesting structural characteristics that are required for inhibiting the CDK2 activity and show potential as drug candidates for the treatment of cancer. The parameters related to the Rule of Five were calculated, and only one of the molecules violated more than one parameter. One of the proposals and one of the drug-like compounds selected by virtual screening indicated to be promising candidates for CDK2-based cancer therapy.

Antileishmanial, antimalarial and antimicrobial activities of the extract and isolated compounds from Austroplenckia populnea (Celastraceae)

Austroplenckia populnea (Celastraceae), known as ""marmelinho do campo"", is used in Brazilian folk medicine as antimicrobial, anti-inflammatory, and antitumoural agent. The aim of the present work was to evaluate the antimicrobial. antileishmanial and antimalarial activities of the crude hydroalcoholic extract of A. populnea (CHE) and some of its isolated compounds. The phytochemical study of the CHE was carried Out affording the isolation of methyl populnoate (1), populnoic acid (2), and stigmast-5-en-3-O-beta-(D-glucopyranoside) (3). This is the first time that the presence of compound 3 in A. populnea is reported. The results showed that the CHE presents antifungal and antibacterial activities, especially against Candida glabrata and Candida albicans, for which the CHE showed IC(50) values of 0.7 mu g mL(-1) and 5.5 mu g mL(-1), respectively, while amphotericin B showed an IC(50) value of 0.1 mu g mL(-1) against both microorganisms. Compounds 1-3 were inactive against all tested microorganisms. In the antileishmanial activity test against Leishmania donovani, the CHE showed an IC(50) value of 52 mu g mL(-1), while compounds 2 and 3 displayed an IC(50) value of 18 mu g mL(-1). In the antimalarial assay against Plasmodium falciparum (D6 and W2 clones), it was observed that all evaluated samples were inactive. In order to compare the effect on the parasites with the toxicity to mammalian cells, the cytotoxicity activity of the isolated compounds was evaluated against Vero cells, showing that all evaluated samples exhibited no cytotoxicity at the maximum dose tested.

Antimicrobial activity of kaurane diterpenes against oral pathogens

Two kaurane diterpenes, ent-kaur-16(17)-en-19-oic acid (KA) and 15-beta-isovaleryloxy-ent-kaur-16(17)-en-19-oic acid (KA-Ival), isolated from Aspilia foliacea, and the methyl ester derivative of KA (KA-Me) were evaluated against oral pathogens. KA was the most active compound, with MIC values of 10 mu g mL(-1) against the following microorganisms: Streptococcus sobrinus, Streptococcus mutans, Streptococcus mitis, Streptococcus sanguinis, and Lactobacillus casei. However, KA did not show significant activity against Streptococcus salivarius and Enterococcus faecalis, with MIC values equal to 100 and 200 mu g mL(-1), respectively. Our results show that KA has potential to be used as a prototype for the discovery of new effective anti-infection agents against microorganisms responsible for caries and periodontal diseases. Moreover, these results allow to conclude that minor structural differences among these diterpenes significantly influence their antimicrobial activity, bringing new perspectives to studies on the structure-activity relationship of this type of metabolites with respect to caries and periodontal diseases.

Antimicrobial activity of the extract and isolated compounds from Baccharis dracunculifolia D. C. (Asteraceae)

Baccharis dracunculifolia D. C. (Asteraceae) is the most important plant source of the Brazilian green propolis. Since propolis is known for its antimicrobial activity, the aim of this work was to evaluate the showed that the leaves extract of B. dracunculifolia (BdE) presents antifungal and antibacterial activities, especially against Candida krusei and Cryptococcus neoformans, for which the BdE showed IC50 values of 65 mu g mL(-1) and 40 mu g mL(-1), respectively In comparison to the BdE, it was observed that the green propolis extract (GPE) showed better antimicrobial activity, displaying an IC50 value of 9 mu g mL(-1) against C krusei. Also, a phytochemical study of the BdE was carried out, affording the isolation of ursolic acid (1), 2 alpha-hydroxy-ursolic acid (2), isosakuranetin (3), aromadendrin-4`-methylether (4), baccharin (5), viscidone (6), hautriwaic acid lactone (7), and the clerodane diterpene 8. This is the first time that the presence of compounds 1, 2, and 8 in B. dracunculifolia has been reported. Among the isolated compounds, 1 and 2 showed antibacterial activity against methicillin-resistant Staphylococcus aureus, displaying IC50 values of 65 mu g mL(-1) and 40 mu g mL(-1), respectively. 3 was active against C neoformans, showing an IC50 value of 15 mu g mL(-1) and a MIC value of 40 mu g mL(-1), while compounds 4-8 were inactive against all tested microorganisms. The results showed that the BdE, similar to the GPE, displays antimicrobial activity, which may be related to the effect of several compounds present in the crude extract.

Antimicrobial Activity of Terpenoids from Copaifera langsdorffii Desf. Against Cariogenic Bacteria

In the present work, the anticariogenic activities of nine labdane type-diterpenes and four sesquiterpenes were investigated. Among these metabolites, (-)-copalic acid (CA) was the most active compound displaying MIC values very promising (ranging from 2.0 to 6.0 mu g/mL) against the main microorganisms responsible for dental caries: Streptococcus salivarius, S. sobrinus, S. mutans, S. mitis, S. sanguinis and Lactobacillus casei. Time kill assays performed with CA against the primary causative agent (S. mutans) revealed that, in the first 12 h, this compound only inhibits the growth of the inoculum (bacteriostatic effect). However, its bactericidal effect is clearly noted thereafter (between 12 and 24 h). Also, CA did not show a synergistic effect when combined with the anticariogenic gold standard (chlorhexidine, CHD) in the checkerboard assays against S. mutans. In conclusion, the results points out CA as an important metabolite in the search for new effective anticariogenic agents. Copyright (C) 2010 John Wiley & Sons, Ltd.

Antiprotozoal, Schistosomicidal, and Antimicrobial Activities of the Essential Oil from the Leaves of Baccharis dracunculifolia

Baccharis dracunculifolia DC. (Asteraceae), popularly known as alecrim do campo, is a native plant from Brazil used in folk medicine as febrifuge, anti-inflammatory, antiseptic, and to treat skin sores. Also, B. dracanculifolia is the most important plant source of the Brazilian green propolis. which is recognized for its antiseptic and antiprotozoal activities. This study aimed at investigating the in vitro antiprotozoal. schistosomicidal, and antimicrobial activities of the essential oil from the leaves of R. dracunculifolia. The essential oil was obtained by hydrodistillation and analyzed by CC and GC/MS, which allowed the identification of 14 compounds, mainly oxygenated sesquiterpenes, such as ( E)nerolidol (33.51%) and spathulenol (16.24%). The essential oil showed activity against promzistigote forms of Leishmania donovani, with IC(50), values of 42 mu g/ml. The essential oil displayed high activity in the schistosomicidal assay, since all pairs of Schistosoma mansoni adult worms were dead after incubation with the essential oil (10, 50, and 100 fig/m1). B. dracunculifolia essential oil was neither cytotoxic against Vero cells, nor active in the antimicrobial and antiplasmodial assays.

Antimicrobial ent-pimarane diterpenes from Viguiera arenaria against Gram-positive bacteria

The dichloromethane crude extract from the roots of Viguiera arenaria (VaDRE) has been employed in an antimicrobial screening against several bacteria responsible for human pathologies. The main diterpenes isolated from this extract, as well as two semi-synthetic pimarane derivatives, were also investigated for the pathogens that were significantly inhibited by the extract (MIC values lower than 100 mu g mL(-1)). The VaDRE extract was significantly active only against Gram-positive microorganisms. The compounds ent-pimara-8(14),15-dien-19-oic acid (PA): PA sodium salt; ent-8(14),15-pimaradien-3 beta-ol; ent-15-pimarene-8 beta,19-diol; and ent-8(14),15-pimaradien-3 beta-acetoxy displayed the highest antibacterial activities (MIC values lower than 10 mu g mL(-1) for most pathogens). In conclusion, our results suggest that pimaranes are an important class of natural products for further investigations in the search of new antibacterial agents. (c) 2009 Elsevier B.V. All rights reserved.

Antimicrobial activity of crude extratcs of Petiveria alliacea L.

Antimicrobial activity of crude extratcs of Petiveria alliacea L.. Petiveria alliacea L. (Phytolaccacea) is an herbaceous plant of great importance in traditional medicine. This species have been widely used in several applications such as antirheumatic, anticarcinogenic, anti-flu, antitussive, analgesic, insecticidal, acaricidal, as well as bactericide and fungicide. Currently, the pathogenic microorganisms are acquiring resistence against the traditional antibiotics, and the search for new herbal antimicrobial agents has been intensified. The objective of this study was to evaluate the antifungal and antibacterial activity of several leaf crude extracts of P. alliacea against several strains of bacterias and yeasts namely Bacilus subtilis, Pseudomonas aeruginosa, Escherichia coli, Streptococcus mutans, Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Candida parapsilosis, Candida kefyr and Candida albicans, using microdilution method. Promising results were observed for the 70% v/v ethanolic extract which presented minimum inhibitory concentration (MIC) from 250 to 760 mu g/mL for yeast. For the bacteria strains tested the MIC ranged between 240 to 3960 mu g/mL, depending of the extractive solution tested.

Improved cure of bacterial vaginosis with single dose of tinidazole (2 g), Lactobacillus rhamnosus GR-1, and Lactobacillus reuteri RC-14: a randomized, double-blind, placebo-controlled trial

Bacterial vaginosis (BV) is the most prevalent vaginal infection worldwide and is characterized by depletion of the indigenous lactobacilli. Antimicrobial therapy is often ineffective. We hypothesized that probiotic Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14 might provide an adjunct to antimicrobial treatment and improve cure rates. Sixty-four Brazilian women diagnosed with BV were randomly assigned to receive a single dose of tinidazole (2 g) supplemented with either 2 placebo capsules or 2 capsules containing L. rhamnosus GR-1 and L. reuteri RC-14 every morning for the following 4 weeks. At the end of treatment (day 28), the probiotic group had a significantly higher cure rate of BV (87.5%) than the placebo group (50.0%) (p = 0.001). In addition, according to the Gram-stain Nugent score, more women were assessed with ""normal`` vaginal microbiota in the probiotic group (75.0% vs. 34.4% in the placebo group; p = 0.011). This study shows that probiotic lactobacilli can provide benefits to women being treated with antibiotics for an infectious condition.

Trypanosoma cruzi: Orchiectomy and dehydroepiandrosterone therapy in infected rats

The ability of gonadal hormones to influence and induce diverse immunological functions during the course of a number of parasitic infections has been extensively studied in the latest decades. Dehydroepiandrosterone and its sulfate are the most abundant steroid hormones secreted by the human adrenal cortex and are considered potent immune-activators. The effects of orchiectomy on the course of Trypanosoma cruzi infection in rats, treated and untreated with DHEA were examined, by comparing blood and cardiac parasitism, macrophage numbers, nitric oxide and IFN-gamma levels. Orchiectomy enhanced resistance against infection with elevated numbers of macrophages, enhanced concentrations of NO and IFN-gamma and reduced amastigote burdens in heart when compared to control animals. DHEA replacement exerted a synergistic effect, up-modulating the immune response. Male sex steroids appear to play fundamental role in determining the outcome of disease, through the regulation and modulation of the activity of the immune response. (C) 2008 Elsevier Inc. All rights reserved.

Circulating matrix metalloproteinase-8 (MMP-8) and MMP-9 are increased in chronic periodontal disease and decrease after non-surgical periodontal therapy

Background: Periodontal disease shares risk factors with cardiovascular diseases and other systemic inflammatory diseases. The present study was designed to assess the circulating matrix metalloproteinases (MMPs) from chronic periodontal disease patients and, subsequently, after periodontal therapy. Methods: We compared the plasma concentrations of MMP-2. MMP-3, MMP-8, MMP-9, tissue inhibitor of metalloproteinase-1 (TIMP-1) and TIMP-2, and total gelatinolytic activity in patients with periodontal disease (n =28) with those of control subjects (n = 22) before and 3 months after non-surgical periodontal therapy. Results: Higher plasma MMP-3, MMP-8, and MMP-9 concentrations were found in periodontal disease patients compared with healthy controls (all P<0.05), whereas MMP-2, TIMP-1, and TIMP-2 levels were not different. Treatment decreased plasma MMP-8 and MMP-9 concentrations by 35% and 39%, respectively (both P<0.02), while no changes were found in controls. MMP-2, MMP-3, TIMP-1, and TIMP-2 remained unaltered in both groups. Plasma gelatinolytic activity was higher in periodontal disease patients compared with controls (P<0.001) and decreased after periodontal therapy (P<0.05). Conclusions: This study showed increased circulating MMP-8 and MMP-9 levels and proteolytic activity in periodontal disease patients that decrease after periodontal therapy. The effects of periodontal therapy suggest that it may attenuate inflammatory chronic diseases. (C) 2009 Published by Elsevier B.V.

Influence of melatonin therapy and orchiectomy on T cell subsets in male Wistar rats infected with Trypanosoma cruzi

Gonadal steroids exert an important influence on the host immune response during infection. Changes resulting from the absence or replacement of gonadal hormones may represent a distinct evolution of a particular parasite. Taking into account the greater susceptibility of males to parasites, the magnitude of the immune response seems to depend on the interaction of many hormones that will act synergistically with other immune cells. The aims of this research were to evaluate the effects of the luck of male sex hormones due to orchiectomy, and the influence of oral administration of melatonin on the immune response of male Wistar rats infected with the Y strain of Trypanosoma cruzi. The percentage of CD3(+) CD4(+) and CD3(+) CD8(+) lymphocyte T cell subsets were evaluated using flow cytometry and the measurement of IL-2 and IL-12. For all parameters examined, a synergistic action of melatonin and orchiectomy on the host`s immune response was observed, promoting an effective response against the parasite during the acute phase of infection. These results offer insight into other possibilities for possibly controlling T. cruzi proliferation through melatonin therapy and also the stimulatory effects on host`s immune response triggered by the absence of male gonadal steroids during the acute phase of infection.

Bioactive Chemical Constituents and Comparative Antimicrobial Activity of Callus Culture and Adult Plant Extracts from Alternanthera tenella

Crude extracts of a callus culture (two culture media) and adult plants (two collections) from Alternanthera tenella Colla (Amaranthaceae) were evaluated for their antibacterial and antifungal activity, in order to investigate the maintenance of antimicrobial activity of the extracts obtained from plants in vivo and in vitro. The antibacterial and antifungal activity was determined against thirty strains of microorganisms including Gram-positive and Gram-negative bacteria, yeasts and dermatophytes. Ethanolic and hexanic extracts of adult plants collected during the same period of the years 1997 and 2002 [Ribeirao Preto (SP), collections 1 and 2] and obtained from plant cell callus culture in two different hormonal media (AtT43 and AtT11) inhibited the growth of bacteria, yeasts and dermatophytes with inhibition halos between 6 and 20 mm. For the crude extracts of adult plants bioassay-guided fractionation, purification, and isolation were performed by chromatographic methods, and the structures of the isolated compounds were established by analysis of chemical and spectral evidences (UV, IR, NMR and ES-MS). Steroids, saponins and flavonoids (aglycones and C-glycosides) were isolated. The minimum inhibitory concentration (MIC) of the isolated compounds varied from 50 to 500 mu g/mL.

Circulating Interleukin-6 and High-Sensitivity C-Reactive Protein Decrease After Periodontal Therapy in Otherwise Healthy Subjects

Background: Periodontal disease has been associated with many chronic inflammatory systemic diseases, and a common chronic inflammation pathway has been suggested for these conditions. However, few studies have evaluated whether periodontal disease, in the absence of other known inflammatory conditions and smoking, affects circulating markers of chronic inflammation. This study compared chronic inflammation markers in control individuals and patients with periodontal disease and observed whether non-surgical periodontal therapy affected inflammatory disease markers after 3 months. Methods: Plasma and serum of 20 controls and 25 patients with periodontal disease were obtained prior to and 3 months after non-surgical periodontal therapy. All patients were non-smokers, they did not use any medication, and they had no history or detectable signs and symptoms of systemic diseases. Periodontal and systemic parameters included probing depth, bleeding on probing, clinical attachment level, hematologic parameters, as well as the following inflammatory markers: interleukin (IL)-6, high-sensitivity C-reactive protein (hs-CRP), CD40 ligand, monocyte chemoattractant protein (MCP)-1, soluble P-selectin (sP-selectin), soluble vascular adhesion molecule (sVCAM)-1, and soluble intercellular adhesion molecule (sICAM)-1. Results: There were no differences in the hematologic parameters of the patients in the control and periodontal disease groups. Among the tested inflammatory markers, IL-6 concentrations were higher in the periodontal disease group at baseline compared to the controls (P=0.006). Therapy was highly effective (P<0.001 for all the analyzed clinical parameters), and a decrease in circulating IL-6 and hs-CRP concentrations was observed 3 months after therapy (P=0.001 and P=0.006, respectively). Our results also suggest that the CD40 ligand marker may have been different in the control and periodontal disease groups prior to the therapy (P=0.009). Conclusions: In apparently otherwise healthy patients, periodontal disease is associated with increased circulating concentrations of IL-6 and hs-CRP, which decreased 3 months after non-surgical periodontal therapy. With regard to the CD40 ligand, MCP-1, sP-selectin, sVCAM-1, and sICAM-1, no changes were seen in the periodontal disease group between baseline and 3 months after therapy. J Periodontol 2009;80:594-602.