Antinociceptive and anti-inflammatory activity of extracts and α-pyrones isolated from Cantinoa stricta.

This study evaluated the composition and the antinociceptive and anti-inflammatory activity of the crude extracts and two isolated compounds, anamarine (ANA) and 10-epi-olguine (eOL), obtained from the leaves of Cantinoa stricta (Lamiaceae). Crude ethanolic extract (EEt) and dichloromethane extract (DCM), selected based on NMR data, were submitted to pharmacological tests in male Swiss mice. The oral administration of EEt and DCM significantly reduced the second phase of formalin-induced nociception (60%), lipopolysaccharide (LPS)-induced mechanical hyperalgesia (90%), and carrageenan (Cg)-induced edema (25%). ANA and eOL, the major compounds in EEt and DCM extracts, administered orally or locally (in the paw), also reduced the LPS-induced mechanical hyperalgesia (Oral ID50 1.9 and 3.9 mg/kg; Local ID50 93.4 and 677.3 ng, respectively) without changing the thermal acute nociception or the motor performance of the animals. Local administration of ANA and eOL also reduced Cg-induced edema (40 and 23%, respectively). These isolated compounds did not change the mechanical hyperalgesia induced by tumor necrosis factor-α, interleukin-1ß, prostaglandin E2, dibutyryl cyclic AMP, or forskolin but reversed the hyperalgesia induced by dopamine, epinephrine, and phorbol 12-myristate 13-acetate. The hyperalgesia induced by epinephrine was reversed in male but not in female mice, in which this response is not dependent on protein kinase C (PKC). These results suggest that C. stricta extracts possess antinociceptive and anti-inflammatory activity which is related to the presence of ANA and eOL. Differently from the known analgesics, these substances seem to exert their action mainly interfering with the sympathetic component of pain, possibly with PKC.

The ethanolic extract of Salvia lachnostachys Benth is not maternotoxic, does not alter reproductive performance, but has teratogenic potential.

Salvia lachnostachys Benth is native to Brazil and has anti-inflammatory, anti-arthritic, cytotoxic, antitumor, and antihyperalgesic activities. The population, including pregnant women, consume this plant to treat pain, inflammation, flu, spasms, insomnia, and depression, mainly. There are no safety reports on the use of this plant during pregnancy. The present study aimed to evaluate the effects of S. lachnostachys ethanolic extract (EESl) on reproductive performance, embryofetal development, and DNA integrity of pregnant female mice. Pregnant females were randomly divided into three experimental groups (n = 10): The Control group was treated with a vehicle, and treatment groups were administered with EESl at 100 and 1000 mg/kg, respectively. Treatment occurred by gavage throughout the gestational period until day 18. Afterward, reproductive performance, embryofetal development, and DNA integrity parameters were evaluated. The results indicated that EESl did not alter any reproductive performance parameters. However, it changed embryofetal outcome through reduced placental weight (EESl 100 mg/kg), decreased fetal weight (EESl 100 and 1000 mg/kg), and increased frequency of small for gestational age fetuses (EESl 1000 mg/kg). In addition, EES1 increased the frequency of external, visceral, and skeletal malformations. Because of the above, it is considered that EESl is not maternotoxic, does not alter reproductive performance, but does alter embryofetal development. Its use in the gestational period is not indicated due to its teratogenic potential.

Fruticuline A, a chemically-defined diterpene, exerts antineoplastic effects in vitro and in vivo by multiple mechanisms.

Natural products have been recognized as important bioactive compounds on the basis of their wide biological properties. Here we investigated the antitumor effect and molecular mechanisms of the diterpene Fruticuline A (fruti) from Salvia lachnostachys, in human cancer cell lineages and Solid Ehrlich Carcinoma in mice. Fruti reduced MCF-7 and HepG2 proliferation by the reduction of Cyclin D1 levels and decreased NF-κB gene levels in both cell types. Furthermore, fruti also induced apoptosis in HepG2 cells, reduced Bcl-2 gene expression and induced necroptosis by increasing Ripk in MCF-7 cells. In mice, fruti prevented tumor development and reduced Cyclin D1, Bcl-2 and Rela gene levels, and reduced the p-NF-κB/NF-κB ratio in tumor tissue. Furthermore, fruti induced necrosis and apoptosis, increased N-acetyl-ß-D-glucosaminidase and TNF-α levels and reduced IL-10 and Vegf levels in tumor tissue. Collectively, fruti exerts antitumor effects through the inhibition of the NF-κB pathway, reducing Cyclin D1 and Bcl-2 levels. In vitro the apoptosis and necroptosis pathways are involved in the cellular death, whereas in vivo, cells undergo necrosis by increased tumor inflammation and reduction of angiogenesis. Thus, fruticuline A acts in tumor cells by multiple mechanisms and represents a promising molecule for drug development in cancer treatment.

Salvia lachnostachys Benth has antitumor and chemopreventive effects against solid Ehrlich carcinoma.

Salvia lachnostachys is an herbaceous plant with anti-inflammatory, analgesic and cytotoxic properties. This study investigated the antitumor effect of an ethanolic extract of Salvia lachnostachys leaves (EES) in a solid Ehrlich carcinoma model. Ehrlich cells were inoculated subcutaneously in the right pelvic member (2 × 106 cells) in female Swiss mice. The animals were treated with vehicle (10 mL kg-1, p.o.), EES (30 and 100 mg kg-1, p.o.), or methotrexate (2.5 mg kg-1, i.p.) for 21 days (early treatment) or 14 days (late treatment) after tumor inoculation, or 10 days before tumor inoculation and continued for 21 days after tumor inoculation (chemopreventive treatment). The acute toxicity test was performed according OECD guidelines Late treatment with EES had no antitumor effect. Early treatment with 100 mg kg-1 EES prevented tumor development, increased tumor necrosis factor-α (TNF-α) levels and decreased tumor superoxide dismutase (SOD) activity, interleukin-10 (IL-10) levels and Cyclin D1 expression, and tumor cell necrosis was observed. Chemopreventive treatment with EES for 10 and 31 days prevented tumor development in the same manner. EES treatment for 31 days decreased hepatic and tumor SOD activity, tumor IL-10 levels and Cyclin D1 expression, and increased tumor reduced glutathione, N-acetylglucosaminidase, reactive oxygen species, lipid peroxidation, TNF-α levels and Nrf2 expression. No toxicity was observed in the acute toxicity assay. In conclusion, EES had an antitumor effect by inhibiting Cyclin D1 expression and increasing inflammation with early and chemopreventive treatment. Modulation of the antioxidant system also contribute for the antitumor effects of EES.

Actions of sesquiterpene lactones isolated from Moquiniastrum polymorphum subsp. floccosum in MCF7 cell line and their potentiating action on doxorubicin.

BACKGROUND: In order to obtain better clinical results in anticancer therapies, polychemotherapy or combination therapies are used. For this, the combinations are required to increase the efficacy and reduce the adverse reactions of the associated chemotherapies. The aim of this study was to evaluate the cytotoxic, apoptotic and (anti)proliferative potential of two sesquiterpene lactones isolated from Moquiniastrum polymorphum, 11,13-diidrozaluzanin C (1) and gochnatiolide C (2), and their associations with chemotherapeutic agents irinotecan, tamoxifen, cisplatin, 5-fluouracyl and doxorubicin in the tumoral lineage of MCF-7 breast adenocarcinoma. METHODS: The analyses were performed by MTT cytotoxicity assays, drug combination index (CI), apoptosis morphological assay and cell proliferation assay. Treatments were evaluated with short exposure times (4 h), followed or not by recovery in drug-free medium for 24 h. For the cell viability assay the statistical analysis was performed using software INSTAT, and the ANOVA/Tukey test was applied. Combination Indices (CI) was made using CompuSyn software and demonstrated through isoboles. The assays that evaluated cell death and proliferation used statistical analysis SAS 9.4 (Statistical Analysis System), and the procedure adopted was PROC NPAR1WAY. The Wilcoxon test at 5% level was applied for comparing statistical differences. RESULTS: The results demonstrated that the compounds decrease cell viability and increase their action when associated with irinotecan, tamoxifen and doxorubicin (CI < 1 and CI = 1). In periods of 4 h-exposure, the compounds cause cell death by apoptosis and after 24 h, they increase the mean number of cells in programmed cell death, especially when treated with 2. In addition, the association with doxorubicin increases the apoptotic potential induced by tested compounds. Both isolates had effect on the reduction of the number of mitoses, especially when 2 at its highest concentration is associated with doxorubicin. CONCLUSIONS: Finally, these compounds are presented as potential agents in chemotherapy combined with doxorubicin, since they trigger the mechanism of apoptosis, which, through the mechanism of action of sesquiterpene lactones, leads to a reduction in toxicity. In addition, the tested compounds have the ability to exert a synergistic action with doxorubicin, possibly by down-regulating the drug resistance mechanisms.

Effects of dichloromethane and butanol fractions of Gochnatia polymorpha floccosa in maternal reproductive outcome, embryo-fetal development and DNA integrity in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Gochnatia polymorpha ssp. floccosa (Asteraceae) also known as ''Cambará'' is used as medicinal plant in Brazil to treat infections and inflammation. Previous studies showed that its ethanolic extract could be bioprospecting of a new anti-inflammatory phytotherapy for use during pregnancy. This work aimed to evaluate dichloromethane (DCM) and butanolic (BT) fractions from G. polymorpha on embryo-fetal development and DNA integrity in mice. MATERIALS AND METHODS: Female mice were treated with 50 and 20mg/kg of the DCM and BT fractions, respectively, during organogenesis and gestational period. RESULTS AND CONCLUSION: The present study shows that DCM and BT fractions from G. polymorpha possess mutagenic activity but are not teratogenic. Based on the fact that the reproductive indices are similar in control and treated animals, we may infer that the mutagenic effect was in somatic cell, at least in part, because the reabsorption number and reabsorption rates did not change in DCM and BT exposed groups.

Hydroethanolic extract of Baccharis trimera promotes gastroprotection and healing of acute and chronic gastric ulcers induced by ethanol and acetic acid.

Ethanol is a psychoactive substance highly consumed around the world whose health problems include gastric lesions. Baccharis trimera is used in folk medicine for the treatment of gastrointestinal disorders. However, few studies have evaluated its biological and toxic effects. To validate the popular use of B. trimera and elucidate its possible antiulcerogenic and cytotoxic mechanisms, a hydroethanolic extract of B. trimera (HEBT) was evaluated in models of gastric lesions. Rats and mice were used to evaluate the protective and antiulcerogenic effects of HEBT on gastric lesions induced by ethanol, acetic acid, and chronic ethanol consumption. The effects of HEBT were also evaluated in a pylorus ligature model and on gastrointestinal motility. The LD50 of HEBT in mice was additionally estimated. HEBT was analyzed by nuclear magnetic resonance, and a high-performance liquid chromatography fingerprint analysis was performed. Oral HEBT administration significantly reduced the lesion area and the oxidative stress induced by acute and chronic ethanol consumption. However, HEBT did not protect against gastric wall mucus depletion and did not alter gastric secretory volume, pH, or total acidity in the pylorus ligature model. Histologically, HEBT accelerated the healing of chronic gastric ulcers in rats, reflected by contractions of the ulcer base. Flavonoids and caffeoylquinic acids were detected in HEBT, which likely contributed to the therapeutic efficacy of HEBT, preventing or reversing ethanol- and acetic acid-induced ulcers, respectively. HEBT antiulcerogenic activity may be partially attributable to the inhibition of free radical generation and subsequent prevention of lipid peroxidation. Our results indicate that HEBT has both gastroprotective and curative activity in animal models, with no toxicity.

Photodynamic antimicrobial effects of bis-indole alkaloid indigo from Indigofera truxillensis Kunth (Leguminosae).

Multidrug-resistant microbial infections represent an exponentially growing problem affecting communities worldwide. Photodynamic therapy is a promising treatment based on the combination of light, oxygen, and a photosensitizer that leads to reactive oxygen species production, such as superoxide (type I mechanism) and singlet oxygen (type II mechanism) that cause massive oxidative damage and consequently the host cell death. Indigofera genus has gained considerable interest due its mutagenic, cytotoxic, and genotoxic activity. Therefore, this study was undertaken to investigate the effect of crude extracts, alkaloidal fraction, and isolated substance derived from Indigofera truxillensis in photodynamic antimicrobial chemotherapy on the viability of bacteria and yeast and evaluation of mechanisms involved. Our results showed that all samples resulted in microbial photoactivation in subinhibitory concentration, with indigo alkaloid presenting a predominant photodynamic action through type I mechanism. The use of CaCl2 and MgCl2 as cell permeabilizing additives also increased gram-negative bacteria susceptibility to indigo.

Sesquiterpene lactones of Moquiniastrum polymorphum subsp. floccosum have antineoplastic effects in Walker-256 tumor-bearing rats.

BACKGROUND AND AIM: This study aimed to evaluate the in vivo antitumor actions and toxicity of the dichloromethane fraction (F1B) of Moquiniastrum polymorphum subsp. floccosum (formerly Gochnatia polymorpha ssp. floccosa), composed of sesquiterpene lactones, against Walker-256 carcinosarcoma in rats. METHODS: Male Wistar rats received 100 mg kg(-1) F1B per day orally for 16 days after subcutaneous inoculation of Walker-256 cells in the pelvic limb. The tumor progression was monitored, and after treatment, tumor weight, oxidative stress, plasma biochemistry, inflammatory parameters, gene expression and histology of tumor and/or liver were evaluated. The toxicity of F1B was analyzed through the relative weight of organs. Additionally, an LD50 test was performed in mice. RESULTS: F1B treatment significantly reduced tumor volume and weight. There was no difference in oxidative stress in tumor tissue after treatment. F1B treatment modified hepatic glutathione and superoxide dismutase, and normalized plasma glucose, alkaline phosphatase, and amylase. F1B did not affect the activity of myeloperoxidase and N-acetylglucosaminidase or the nitric oxide levels in tumor tissue. However, F1B decreased the tumor necrosis factor (TNF)-α levels. Additionally, F1B increased apoptosis in the tumor, mediated by up-regulation of the p53 and Bax gene expression. No clinical signs of toxicity or death were observed in the rats treated with F1B. The LD50 calculated for mice was 1209 mg kg(-1). CONCLUSIONS: F1B, which is rich in sesquiterpene lactones, showed antitumor activity against Walker-256 carcinosarcoma. This effect may be, at least in part, related to the induction of apoptosis and inhibition of TNF-α signaling.

Anti-Inflammatory and Antihyperalgesic Activities of Ethanolic Extract and Fruticulin A from Salvia lachnostachys Leaves in Mice.

The anti-inflammatory and analgesic effects of the ethanolic extract (SLEE) and fruticulin A from the leaves of Salvia lachnostachys were evaluated in mice, using experimental models of inflammation (paw oedema and pleurisy induced by carrageenan injection) and hyperalgesia (electronic Von Frey). Oral administration of SLEE (30, 100, and 300 mg/kg) and fruticulin A (0.3 and 3.0 mg/kg) decreased the total leucocytes number in pleural lavage, protein extravasation, and paw oedema. SLEE (100 mg/kg) and fruticulin A (3 mg/kg) also exhibited antihyperalgesic activity in carrageenan induced mechanical hyperalgesia. In addition, fruticulin A (3 mg/kg) prevented mechanical hyperalgesia, inhibiting TNF but not L-DOPA-induced mechanical hyperalgesia. In conclusion, SLEE and fruticulin A display anti-inflammatory and analgesic properties. Therefore, fruticulin A is at least partially responsible for the activity observed in the ethanolic extract of Salvia lachnostachys.

Gochnatia polymorpha ssp. floccosa: bioprospecting of an anti-inflammatory phytotherapy for use during pregnancy.

ETHNOPHARMACOLOGICAL RELEVANCE: Gochnatia polymorpha ssp. floccosa is used in folk medicine to treat inflammation and infections. Non-steroidal anti-inflammatory drugs (NSAIDs) are the most commonly consumed medications during pregnancy in women with inflammatory diseases. However, the relationship between the use of NSAIDs and the risk of miscarriage and birth defects and/or benefits is not fully understood. Thus, an investigation regarding the use of Gochnatia polymorpha during gestation is of relevance for developing safe anti-inflammatory drugs for use during pregnancy. MATERIALS AND METHODS: The pregnant females were randomly divided into 5 groups. Control group received a hydroalcoholic solution (1.2%), via gavage, for at least 15 days prior to mating and throughout the gestational period. The pre-treatment group received Gochnatia polymorpha ethanol extract (GPEE), via gavage, at a dose of 100mg/kg body weight (b.w.) for at least 15 days prior to mating and up to the appearance of the vaginal plug. The organogenesis group received GPEE at a dose of 100mg/kg (b.w.), via gavage, on the 5-15th gestacional day. The pregnancy group received GPEE at a dose of 100mg/kg (b.w.), via gavage, throughout the gestational period (from the 1st to the 18th day of pregnancy). The pre+pregnancy group received GPEE at a dose of 100mg/kg (b.w.), via gavage, for at least 15 days prior to mating and throughout the entire gestational period. The clinical signals of maternal toxicity and teratogenesis were evaluated. Additional assays to evaluate chronic inflammation, antigenotoxicity and immunomodolatory activity were performed. RESULTS AND CONCLUSIONS: The results indicated that GPEE does not interfere with reproductive performance or embryo-fetal development but does correlate with reduced weight and fetal length. The extract was not teratogenic or mutagenic or an immunomodulator. However, GPEE did exhibit effective anti-inflammatory activity. Based on this study, it can be inferred that GPEE is an important, safe anti-inflammatory agent for use during pregnancy according to the experimental design we utilized, which opens up possibilities for the bioprospecting of a new anti-inflammatory phytotherapy for use during pregnancy.

Antiproliferative activity and induction of apoptosis in PC-3 cells by the chalcone cardamonin from Campomanesia adamantium (Myrtaceae) in a bioactivity-guided study.

The Myrtaceae family is a common source of medicines used in the treatment of numerous diseases in South America. In Brazil, fruits of the Campomanesia species are widely used to make liqueurs, juices and sweets, whereas leaves are traditionally employed as a medicine for dysentery, stomach problems, diarrhea, cystitis and urethritis. Ethanol extracts of Campomanesia adamantium (Myrtaceae) leaves and fruits were evaluated against prostate cancer cells (PC-3). The compound (2E)-1-(2,4-dihydroxy-6-methoxyphenyl)-3-phenylprop-2-en-1-one, cardamonin) was isolated from ethanol extracts of C. adamantium leaves in a bioactivity-guided study and quantified by UPLC-MS/MS. In vitro studies showed that the isolated chalcone cardamonin inhibited prostate cancer cell proliferation and decreased the expression of NFkB1. Moreover, analysis by flow cytometry showed that this compound induced DNA fragmentation, suggesting an effect on apoptosis induction in the PC-3 cell line.

Uncaria tomentosa exerts extensive anti-neoplastic effects against the Walker-256 tumour by modulating oxidative stress and not by alkaloid activity.

This study aimed to compare the anti-neoplastic effects of an Uncaria tomentosa (UT) brute hydroethanolic (BHE) extract with those of two fractions derived from it. These fractions are choroformic (CHCl3) and n-butanolic (BuOH), rich in pentacyclic oxindole alkaloids (POA) and antioxidant substances, respectively. The cancer model was the subcutaneous inoculation of Walker-256 tumour cells in the pelvic limb of male Wistar rat. Subsequently to the inoculation, gavage with BHE extract (50 mg.kg(-1)) or its fractions (as per the yield of the fractioning process) or vehicle (Control) was performed during 14 days. Baseline values, corresponding to individuals without tumour or treatment with UT, were also included. After treatment, tumour volume and mass, plasma biochemistry, oxidative stress in liver and tumour, TNF-α level in liver and tumour homogenates, and survival rates were analysed. Both the BHE extract and its BuOH fraction successfully reduced tumour weight and volume, and modulated anti-oxidant systems. The hepatic TNF-α level indicated a greater effect from the BHE extract as compared to its BuOH fraction. Importantly, both the BHE extract and its BuOH fraction increased the survival time of the tumour-bearing animals. Inversely, the CHCl3 fraction was ineffective. These data represent an in vivo demonstration of the importance of the modulation of oxidative stress as part of the anti-neoplastic activity of UT, as well as constitute evidence of the lack of activity of isolated POAs in the primary tumour of this tumour lineage. These effects are possibly resulting from a synergic combination of substances, most of them with antioxidant properties.

Secondary metabolites and biological properties of Gesneriaceae species.

The family Gesneriaceae comprises ca. 150 genera and 3000 species, distributed in the tropics around the world. It is constituted of herbs, lianas, or shrubs, frequently with ornamental potential, due to the beauty of their flowers. Some species have been used in traditional medicine, mainly against fever, cough, colds, snakebite, pains, and infectious and inflammatory diseases. Although Gesneriaceae are a large family, only few species were chemically investigated, and this took place mainly in the last decade. In the present work, chemical and pharmacological studies on Gesneriaceae are reviewed based on original articles published. Altogether 300 compounds have been reported in Gesneriaceae species, including flavonoids, terpenes and steroids, phenolic glucosides, simple phenolics, quinones, lignans, xanthones, and compounds with unusual skeletons. Several species had been used in folk medicine, and some constituents have shown biological activities, such as antimicrobial, anti-inflamatory, antioxidant, and antitumor properties.

Morphoanatomical and phytochemical studies of Salvia lachnostachys (Lamiaceae).

Salvia lachnostachys Benth., Lamiaceae, is a endemic species from southern Brazil. The essential oil of its leaves and flowers is mainly constituted by aliphatic compounds, such as dodecanoic acid, with sesquiterpenes as minor constituents. This work evaluated the morphology, anatomy, microchemistry, and phytochemistry of S. lachnostachys to provide advanced knowledge of Brazilian plants with medicinal potential. Light and scanning electron microscopy techniques were used in the anatomical and microchemical studies. Compounds were isolated by chromatographic techniques, identified by analysis of their NMR spectra and compared with published data. S. lachnostachys can be distinguished from other related species mainly by its petiolate leaves, terminal inflorescence, persistent bracts, and villous-glandular corolla. The stem and leaves of S. lachnostachys display anatomical characteristics common to the family Lamiaceae. However, this species can be distinguished from other family members by the morphology and the presence of eglandular and glandular trichomes, as well as the organization of the vascular bundles of the petiole. The phytochemical results revealed that S. lacnostachys produces oleanolic and ursolic acids in addition to the diterpene fruticuline A, which is a rare compound, previously found only in Salvia fruticulosa Benth. and S. corrugata Vahl. Ursolic and oleanolic acids are bioactive triterpenes that exhibit antiatherosclerotic, anticancer, antihypertensive, antinflammatory, antileukemic, antimutagenic, antioxidant, antiproliferative, and antiviral activities, and fruticuline A has antibacterial activity.

Chemical composition and cytotoxic activity of the essential oil from the leaves of Casearia lasiophylla

The essential oil obtained by hydrodistillation from fresh leaves of Casearia lasiophylla Eichler, Salicaceae, was analyzed by gas capillary (GC/FID and GC/MS). The cytotoxicity of the leaves essential oil was tested in vitro againstU251 (glioma), UACC-62 (melanoma), MCF-7 (breast), NC1-ADR/RES (ovarian-resistant), NCI-H460 (lung), PC03 (prostate), OVCAR-3 (ovarian), HT-29 (colon) and K562 (leukemia) human cancer cells and against VERO (no cancer cell). The yield of oil was 0.02 percent. Fifty two compounds were identified, representing 87.1 percent of the total of the oil. The main components were identified as germacrene D (18.6 percent), β-caryophyllene (14.7 percent), δ-cadinene (6.2 percent), and α-cadinol (5.4 percent). The oil exhibited antiproliferative activity against all cell lines (TGI<100 µg/mL), with exception of NCI-H460 cell line (TGI 191.31 µg/mL). The highest activity was observed against UACC-62 (TGI 7.30 µg/mL), and K562 (TGI 7.56 µg/mL) cell lines. The observed activity could be related to high content of germacrene D and β-caryophyllene, compounds known as cytotoxic.

Free radical scavenging activity, determination of phenolic compounds and HPLC-DAD/ESI-MS profile of Campomanesia adamantium leaves.

Numerous diseases are induced by free radicals via lipid peroxidation, protein peroxidation and DNA damage. It has been known that a variety of plant extracts have antioxidant activity to scavenge free radicals. Campomanesia adamantium (Myrtaceae) is a small tree with edible fruit, commonly known as "guavira" or "guabiroba-branca" that has been used in popular medicine as depurative anti-diarrhoeic, antiinflammatory, anti-rheumatic and to liver diseases. In this study, the antiradical activities of ethanol crude extract of the leaves from C. adamantium and the ethyl acetate and butanol fractions obtained by partition, were determined using DPPH (2,2-Diphenyl-1-picrylhydrazyl radical) and ORAC-FL (Oxygen Radical Absorbance Capacity) assays. The total phenol content in the samples was estimated by Folin Ciocalteau method (FCR). In an initial evaluation the ethanolic extract and the fractions ethyl acetate and butanol have shown levels of phenolic compounds between 15- 74 mg GAE/g in FCR assay, showed DPPH free-radical scavenging activity with SC50 in the range of 7.77-13.35 microg/mL and demonstrated antioxidant capacity between 2648-3502 micromol TE/g of extract and fractions in the ORAC-FL assay. HPLC-DAD and ESI-MS analysis revealed were that the extract of the leaves of C. adamantium studied appears to contain flavonoids as major constituents, including isoquercetrin and quercetin that exhibit proven antioxidant activity.

Antioxidant capacity and phenolic content of four Myrtaceae plants of the south of Brazil.

Antioxidant compounds can be useful to prevent several degenerative diseases or as preservative in food and toiletries. Species of the Myrtaceae family are able to accumulate phenolic substances and those are closely related to the antioxidant activity due to their capacity to scavenge free radicals, protect against lipid peroxidation and quench reactive oxygen species. These facts prompted us to investigate the antioxidant capacity of the ethanolic extracts of the leaves of four Myrtaceae plants collected of the south of Brazil: Eugenia chlorophylla O. Berg., Eugenia pyriformis Cambess, Myrcia laruotteana Cambess and Myrcia obtecta (Berg) Kiacrsk. The antioxidant potential was performed using the DPPH (a single electron transfer reaction based assay) and ORAC (Oxygen Radical Absorbance Capacity, a hydrogen atom transfer reaction based assay) assays. Moreover, the total soluble phenolic content was also measured using the Folin-Ciocalteu reagent. A preliminary evaluation of the ethanolic extracts of these Myrtaceae plants revealed high levels of phenolic compounds (343.7-429.3 mg GAE) as well as high antioxidant activity according to both methods (1338 a 3785 micromol of TE/g of extract in ORAC and SC50 in the range of 1.70 and 33.7 microg/mL in the DPPH). The highest antioxidant activity obtained by DPPH assay was exhibited by ethanol extract of the leaves of E. pyriformis (1.70 microg/mL), followed by extracts of M. laruotteana (3.38 microg/mL) and M. obtecta (6.66 microg/mL). In comparison with controls, in the DPPH assay, the extract of E. pyriformis was more active than trolox (SC50 = 2.55 microg/mL), while the extracts of M. laruotteana and M. obtecta were more actives than quercetin (SC50 = 7.80 microg/mL). In the ORAC assay, all species also show good antioxidant capacity (>1000 micromol of TE/g). Initial HPLC-UV/DAD and ESI-MS confirmed the presence of phenolic acids constituents in the ethanol extracts. The results indicate the presence of compounds possessing promising antioxidant/free-radical scavenging activity in the analyzed extracts of Myrcia and Eugenia plants of the south of Brazil.

Hypotensive mechanism of the extracts and artemetin isolated from Achillea millefolium L. (Asteraceae) in rats.

Traditional uses of Achillea millefolium L. (Asteraceae) include the treatment of cardiovascular diseases. In the present study, we used anesthetized rats to assess the hypotensive effect of a hydroethanolic extract (HEAM), and its dichloromethane (DCM), ethyl acetate (EA), butanolic (BT), and dichloromethane-2 (DCM-2) fractions, besides the flavonoid artemetin, isolated from A. millefolium. The oral administration of HEAM (100-300 mg/kg), DCM (20mg/kg), DCM-2 (10-30 mg/kg), but not EA (10 mg/kg) and BT (50 mg/kg) fractions significantly reduced the mean arterial pressure (MAP) of normotensive rats. The phytochemical analysis by NMR (1)H of DCM and DCM-2 fractions revealed high amounts of artemetin, that was isolated and administered by either oral (1.5 mg/kg) or intravenous (0.15-1.5 mg/kg) routes in rats. This flavonoid was able to dose-dependently reduce the MAP, up to 11.47 ± 1.5 mmHg (1.5 mg/kg, i.v.). To investigate if artemetin-induced hypotension was related to angiotensin-converting enzyme inhibition, we evaluated the influence of this flavonoid on the vascular effects of both angiotensin I and bradykinin. Intravenous injection of artemetin (0.75 mg/kg) significantly reduced the hypertensive response to angiotensin I while increased the average length of bradykinin-induced hypotension. Artemetin (1.5 mg/kg, p.o.) was also able to reduce plasma (about 37%) and vascular (up to 63%) ACE activity in vitro, compared to control group. On the other hand, artemetin did not change angiotensin II-induced hypertension. Our study is the first showing the hypotensive effects induced by the extract and fractions obtained from A. millefollium. In addition, our results disclosed that this effect may be, at least in part, associated with high levels of artemetin and its ability to decrease angiotensin II generation in vivo, by ACE inhibition.

Essential oils from neotropical Myrtaceae: chemical diversity and biological properties.

Myrtaceae family (121 genera, 3800-5800 spp.) is one of the most important families in tropical forests. They are aromatic trees or shrubs, which frequently produce edible fruits. In the neotropics, ca. 1000 species were found. Several members of this family are used in folk medicine, mainly as an antidiarrheal, antimicrobial, antioxidant, cleanser, antirheumatic, and anti-inflammatory agent and to decrease the blood cholesterol. In addition, some fruits are eaten fresh or used to make juices, liqueurs, and sweets very much appreciated by people. The flavor composition of some fruits belonging to the Myrtaceae family has been extensively studied due to their pleasant and intense aromas. Most of the essential oils of neotropical Myrtaceae analyzed so far are characterized by predominance of sesquiterpenes, some with important biological properties. In the present work, chemical and pharmacological studies carried out on neotropical Myrtaceae species are reviewed, based on original articles published since 1980. The uses in folk medicine and chemotaxonomic importance of secondary metabolites are also briefly discussed.