Carina Denny

Antibacterial Activity of Essential Oils and Their Isolated Constituents against Cariogenic Bacteria: A Systematic Review

Dental caries remains the most prevalent and costly oral infectious disease worldwide. Several methods have been employed to prevent this biofilm-dependent disease, including the use of essential oils (EOs). In this systematic review, we discuss the antibacterial activity of EOs and their isolated constituents in view of a potential applicability in novel dental formulations. Seven databases were systematically searched for clinical trials, in situ, in vivo and in vitro studies addressing the topic published up to date. Most of the knowledge in the literature is based on in vitro studies assessing the effects of EOs on caries-related streptococci (mainly Streptococcus mutans) and lactobacilli, and on a limited number of clinical trials. The most promising species with antibacterial potential against cariogenic bacteria are: Achillea ligustica, Baccharis dracunculifolia, Croton cajucara, Cryptomeria japonica, Coriandrum sativum, Eugenia caryophyllata, Lippia sidoides, Ocimum americanum, and Rosmarinus officinalis. In some cases, the major phytochemical compounds determine the biological properties of EOs. Menthol and eugenol were considered outstanding compounds demonstrating an antibacterial potential. Only L. sidoides mouthwash (1%) has shown clinical antimicrobial effects against oral pathogens thus far. This review suggests avenues for further non-clinical and clinical studies with the most promising EOs and their isolated constituents bioprospected worldwide.

Winery by-products: extraction optimization, phenolic composition and cytotoxic evaluation to act as a new source of scavenging of reactive oxygen species.

Nearly 20 million tons of winery by-products, with many biological activities, are discarded each year in the world. The extraction of bioactive compounds from Chenin Blanc, Petit Verdot, and Syrah grape by-products, produced in the semi-arid region in Brazil, was optimized by a Central Composite Rotatable Design. The phenolic compounds profile, antioxidant capacity against synthetic free radicals (DPPH and ABTS), reactive oxygen species (ROS; peroxyl radical, superoxide radical, hypochlorous acid), cytotoxicity assay (MTT) and quantification of TNF-α production in RAW 264.7 cells were conducted. Gallic acid, syringic acid, procyanidins B1 and B2, catechin, epicatechin, epicatechin gallate, quercetin 3-β-d-glucoside, delfinidin 3-glucoside, peonidin 3-O-glucoside, and malvidin 3-glucoside were the main phenolic compounds identified. In general, rachis showed higher antioxidant capacity than pomace extract, especially for Chenin Blanc. All extracts showed low cytotoxicity against RAW 264.7 cells and Petit Verdot pomace suppressed TNF-α liberation in vitro. Therefore, these winery by-products can be considered good sources of bioactive compounds, with great potential for application in the food and pharmaceutical industries.

Geopropolis from Melipona scutellaris decreases the mechanical inflammatory hypernociception by inhibiting the production of IL-1β and TNF-α

ETHNOPHARMACOLOGICAL RELEVANCE The pharmacological activity of geopropolis collected by stingless bees (important and threatened pollinators), a product widely used in folk medicine by several communities in Brazil, especially in the Northeast Region, needs to be studied. OBJECTIVE The aim of this study was to evaluate the antinociceptive activity of Melipona scutellaris geopropolis (stingless bee) using different models of nociception. MATERIAL AND METHODS The antinociceptive activity of the ethanolic extract of geopropolis (EEGP) and fractions was evaluated using writhing induced by acetic acid, formalin test, carrageenan-induced hypernociception, and quantification of IL-1β and TNF-α. The chemical composition was assessed by quantification of total flavonoids and phenolic compounds. RESULTS EEGP and its hexane and aqueous fractions showed antinociceptive activity. Both EEGP and its aqueous fraction presented activity in the mechanical inflammatory hypernociception induced by the carrageenan model, an effect mediated by the inhibition of IL-1β and TNF-α. The chemical composition of EEGP and its hexane and aqueous fractions showed a significant presence of phenolic compounds and absence of flavonoids. CONCLUSION Our data indicate that geopropolis is a natural source of bioactive substances with promising antinociceptive activity.

Furanoditerpenes from Pterodon pubescens benth with selective in vitro anticancer activity for prostate cell line

Activity guided fractionation of Pterodon pubescens Benth. methylene chloride-soluble fraction afforded novel 6α-acetoxi 7β-hydroxy-vouacapan 1 and four known diterpene furans 2, 3, 4, 5. The compounds were evaluated for in vitro cytotoxic activities against human normal cells and tumour cell lines UACC-62 (melanoma), MCF-7 (breast), NCI-H460 (lung, non-small cells), OVCAR-03 (ovarian), PC-3 (prostate), HT-29 (colon), 786-0 (renal), K562 (leukemia) and NCI-ADR/RES (ovarian expressing phenotype multiple drugs resistance). Results were expressed by three concentration dependent parameters GI50 (concentration that produces 50% growth inhibition), TGI (concentration that produces total growth inhibition or cytostatic effect) and LC50 (concentration that produces -50% growth, a cytotoxicity parameter). Also, in vitro cytotoxicity was evaluated against 3T3 cell line (mouse embryonic fibroblasts). Antiproliferative properties of compounds 1, 4 and 5 are herein reported for the first time. These compounds showed selectivity in a concentration-dependent way against human PC-3. Compound 1 demonstrated selectivity 26 fold more potent than the positive control, doxorubicin, for PC-3 (prostrate) cell line based on GI50 values, causing cytostatic effect (TGI value) at a concentration fifteen times less than positive control. Moreover comparison of 50% lethal concentration (LC50 value) with positive control (doxorubicin) suggested that compound 1 was less toxic.

Bioactive Fraction of Geopropolis from Melipona scutellaris Decreases Neutrophils Migration in the Inflammatory Process: Involvement of Nitric Oxide Pathway

The aim of this study was to evaluate the activity of the ethanolic extract of geopropolis (EEGP) from Melipona scutellaris and its fractions on the modulation of neutrophil migration in the inflammatory process, and the participation of nitric oxide (NO) pathway, as well as to check the chemical profile of the bioactive fraction. EEGP and its aqueous fraction decreased neutrophil migration in the peritoneal cavity and also the interaction of leukocytes (rolling and adhesion) with endothelial cells. The levels of chemokines CXCL1/KC and CXCL2/MIP-2 were not altered after treatment with EEGP and the aqueous fraction. It was found that the injection of NO pathway antagonists abolished the EEGP and the aqueous fraction inhibitory activity on the neutrophil migration. The expression of intercellular adhesion molecule type 1 (ICAM-1) was reduced, and nitrite levels increased after treatment with EEGP and aqueous fraction. In the carrageenan-induced paw edema model, EEGP and the aqueous fraction showed antiedema activity. No pattern of flavonoid and phenolic acid commonly found in propolis samples of Apis mellifera could be detected in the aqueous fraction samples. These data indicate that the aqueous fraction found has promising bioactive substances with anti-inflammatory activity.

Chemical Characterization and Antioxidant, Antimicrobial, and Anti-Inflammatory Activities of South Brazilian Organic Propolis.

South Brazilian organic propolis (OP), which has never been studied before, was assessed and its chemical composition, scavenging potential of reactive oxygen species, antimicrobial and anti-inflammatory activities are herein presented. Based on the chemical profile obtained using HPLC, OP was grouped into seven variants (OP1–OP7) and all of them exhibited high scavenging activity, mainly against superoxide and hypochlorous acid species. OP1, OP2, and OP3 had the smallest minimal inhibitory concentration (MIC) against Gram-positive bacteria Streptococcus mutans, Streptococcus oralis, and Streptococcus aureus (12.5–100 μg/mL). OP1, OP2, OP3, and OP4 were more effective against Pseudomonas aeruginosa (Gram-negative), with MIC values ranging from 100 to 200 μg/mL. OP6 showed anti-inflammatory activity by decreasing NF-kB activation and TNF-α release in RAW 264.7 macrophages, and expressing the NF-κB-luciferase reporter stable gene. Therefore, south Brazilian OP can be considered an excellent source of bioactive compounds with great potential of application in the pharmaceutical and food industry.

Main pathways of action of Brazilian red propolis on the modulation of neutrophils migration in the inflammatory process

BACKGROUND Brazilian propolis is popularly used as treatment for different diseases including the ones with inflammatory origin. Brazilian red propolis chemical profile and its anti-inflammatory properties were recently described however, its mechanism of action has not been investigated yet. AIM Elucidate Brazilian red propolis major pathways of action on the modulation of neutrophil migration during the inflammatory process. METHODS The ethanolic extract of propolis (EEP) activity was investigated for neutrophil migration into the peritoneal cavity, intravital microscopy (rolling and adhesion of leukocytes), quantification of cytokines TNF-α, IL-1β and chemokines CXCL1/KC, CXCL2/MIP-2, neutrophil chemotaxis induced by CXCL2/MIP-2, calcium influx and CXCR2 expression on neutrophils. RESULTS EEP at 10mg/kg prevented neutrophil migration into peritoneal cavity (p < 0.05), reduced leukocyte rolling and adhesion on the mesenteric microcirculation (p < 0.05) and inhibited the release TNF-α, IL-1β, CXCL1/KC and CXCL2/MIP-2 (p < 0.05). EEP at 0.01, 0.1 and 1µg/ml reduced the CXCL2/MIP-2-induced neutrophils chemotaxis (p < 0.05) without affect cell viability (p > 0.05).EEP at 1µg/ml decreased the calcium influx induced by CXCL2/MIP-2 (p<0.05). On the other hand, none of EEP concentrations tested altered CXCR2 expression by neutrophils (p>0.05). CONCLUSION Brazilian red propolis appears as a promising anti-inflammatory natural product which mechanism seems to be by reducing leukocyte rolling and adhesion; TNF-α, IL-1β, CXCL1/KC and CXCL2/MIP-2 release; CXCL2/MIP-2-induced chemotaxis and calcium influx.

Gastroprotective Effect of Geopropolis from Melipona scutellaris Is Dependent on Production of Nitric Oxide and Prostaglandin

The aim of this study was to evaluate the gastroprotective activity of ethanolic extract of geopropolis (EEGP) from Melipona scutellaris and to investigate the possible mechanisms of action. The gastroprotective activity of the EEGP was evaluated using model ulcer induced by ethanol. To elucidate the possible mechanisms of action, we investigated the involvement of the nonprotein sulfhydryl (NP-SH) groups, nitric oxide and prostaglandins. In addition, the antisecretory activity of EEGP was also evaluated by pylorus ligated model. The EEGP orally administrated (300 mg/kg) reduced the ulcerative lesions induced by the ethanol (P < 0.05). Regarding the mechanism of action, the prior administration of nitric oxide and prostaglandins antagonists suppressed the activity of gastroprotective EEGP (P < 0.05). On the other hand the gastroprotective activity of EEGP was kept in the group pretreated with the antagonist of the NP-SH groups; furthermore the antisecretory activity was not significant (P > 0.05). These results support the alternative medicine use of geopropolis as gastroprotective and the activities observed show to be related to nitric oxide and prostaglandins production.

Atividade antiproliferativa dos extratos e da fração orgânica obtidos das folhas de Virola sebifera Aubl. (Myristicaceae)

Barks of Virola sebifera (Myristicaceae) used by Amazonian Indian communities in hallucinogenic snuff preparations have yielded dimethyltryptamine and derivatives. Considering the importance of the alkaloids isolated from plants for the development of chemotherapy, and the presence of these compounds in several Virola species, the scope of this work was to evaluate the antiproliferative activity of the extracts and the organic fraction from Virola sebifera leaves. The crude dichloromethane extract was the most active with selectivity for lung line (NCI-460) - IC50: 4.46 µg/mL, as well as the organic fraction (OF) - IC50: 6.91 µg/mL. The observed activity could probably be attributed to alkaloids or nitrogen compounds that were evidenced by the Dragendorff reagent. However, the future purification of OF will be necessary to prove the presence of alkaloids and their role in the antiproliferative activity in human cells as well as isolating and identifying these compounds.

Exploration of avocado by-products as natural sources of bioactive compounds

This study aimed to evaluate the antioxidant, anti-inflammatory, and cytotoxic properties and phenolic composition of peel and seed of avocado varieties Hass and Fuerte using green solvents. Ethanol soluble compounds were identified in peel and seed of both varieties using HPLC-MS/MS and quantified using HPLC-DAD. Agro-industrial by-products of both varieties exhibited high radical scavenging activity against synthetic free radicals (DPPH and ABTS) and reactive oxygen species (peroxyl, superoxide, and hypochlorous acid) and high ability to reduce Fe3+ to Fe2+. The main compounds with significant contribution to the antioxidant activity determined by online HPLC-ABTS●+ analyses were procyanidin B2 and epicatechin in the peel and trans-5-O-caffeoyl-D-quinic acid, procyanidin B1, catechin, and epicatechin in the seed. Peel of Fuerte significantly suppressed TNF-α and nitric oxide (NO) release (459.3 pg/mL and 8.5 μM, respectively), possibly because of the high phenolic content and antioxidant activity detected. Avocado agro-industrial by-products can be used for food and pharmaceutical purposes due to their antioxidant and anti-inflammatory properties.