Gall inducer Dasineura sp. alters the polyphenol profile and antioxidant activity of Peumus boldus stems.

Peumus boldus, a tree native to Chile, is extensively used for medicinal purposes due to its richness in alkaloids and antioxidant polyphenols. A species of galling insect, Dasineura sp. induces structural and chemical changes on P. boldus stems while its galls are established and developed. Taking into account the antioxidant properties of P. boldus polyphenols, it would be expected that Dasineura sp. induces changes in the accumulation sites, chemical profile, and antioxidant activity of the P. boldus stem polyphenols, related to different reactive oxygen species (ROS) production levels during gall development. Dasineura sp. induces changes in the accumulation sites of total polyphenols, flavonols, and lignin, redirecting their accumulation toward the sites of greatest production of H2O2 and O2.-. Although changes in total polyphenol content would be expected, this did not vary significantly between non-galled and galled stems. However, the galling insect induced changes in the profile and concentration of soluble polyphenols, leading to the gall extracts' antioxidant capacity decreasing significantly during the maturation and senescence stages. Additionally, during the maturation stage, lignin deposition increases in the more peripheral gall tissues, which also contributes to ROS dissipation. The differences in the different gall developmental stages' antioxidant activity could be related to the identity and concentration of phenolic compounds in each gall extract, rather than to the total phenol content. Regardless of the mechanisms involved, the dissipation of the ROS generated by Dasineura sp. activity occurs, restoring the redox balance in galls and guaranteeing the success of the inducer.

Phytochemical characterization and biological activities of Plectranthus barbatus Andrews / Caracterização fitoquímica e atividades biológicas de Plectranthus barbatus Andrews

Plectranthus barbatus Andrews (Lamiaceae) is widely distributed in the world and has a range of popular therapeutic indications. This work aimed to evaluate the phytochemical characterization of two leaf extracts of P. barbatus, and their antimicrobial, antineoplastic and immunomodulatory potential. After collection, herborization and obtainment of the P. barbatus aqueous extract (PBA) and acetone:water 7:3 P. barbatus organic extract (PBO), the phytochemical characterization was performed by high-performance liquid chromatography (HPLC). The antimicrobial activity was performed to determine the minimum inhibitory concentration (MIC) against eight bacterial strains using the microdilution test and the fungus Trichophyton rubrum by disc diffusion assay and microdilution test. Cytotoxicity was assessed by MTT and trypan blue methods in normal peripheral blood mononuclear cells (PBMCs) at concentrations ranged between 0.1 to 100 µg.mL-1 and in neoplastic cell lines Toledo, K562, DU-145 and PANC-1 at 1, 10 and 100 µg.mL-1 . Immunomodulatory activity, was evaluated by sandwich ELISA of proinflammatory cytokines at BALB/c mice splenocytes cultures supernatant. Both extracts presented flavonoids, cinnamic derivatives, steroids and ellagic acid. PBO showed bacteriostatic activity against Acinetobacter baumannii (MIC = 250 µg.mL-1) clinical isolate and PBA fungistatic activity against Trichophyton rubrum (MIC = 800 µg.mL-1). The extracts did not exhibit toxicity to PBMCs and neoplastic cells (IC50 > 100 µg.mL-1). Additionally, PBO at 100 µg.mL-1 significantly inhibited IFN-γ and IL-17A cytokines (p = 0.03). Plectranthus barbatus is a potential candidate for therapeutic use due to its low toxicity in healthy human cells and exhibits biological activities of medical interest as bacteriostatic, fungistatic and immunomodulatory.

Plectranthus barbatus Andrews (Lamiaceae) é amplamente distribuída no mundo e com uma série de indicações terapêuticas populares. Este trabalho teve como objetivo avaliar a caracterização fitoquímica de dois extratos da folha de P. barbatus e seu potencial antimicrobiano, antineoplásico e imunomodulador. Após coleta, herborização e obtenção do extrato aquoso (PBA) e acetona: água 7: 3 (orgânico) (PBO) de P. barbatus, a caracterização fitoquímica foi realizada por cromatografia líquida de alta eficiência (CLAE). A atividade antimicrobiana foi realizada para determinar a concentração inibitória mínima (CIM) contra oito cepas bacterianas usando o teste de microdiluição e o fungo Trichophyton rubrum por ensaio de difusão em disco e teste de microdiluição. A citotoxicidade foi avaliada por métodos MTT e azul de tripan em células normais mononucleares do sangue periférico (CMSP) em concentrações variadas entre 0,1 a 100 µg.mL-1 e nas linhagens celulares neoplásicas Toledo, K562, DU-145 e PANC-1 em 1, 10 e 100 µg.mL-1 . A atividade imunomoduladora foi avaliada por ELISA sanduíche de citocinas pró-inflamatórias em sobrenadante de culturas de esplenócitos de camundongos BALB/c. Ambos os extratos apresentaram flavonoides, derivados cinâmicos, esteróides e ácido elágico. O PBO mostrou atividade bacteriostática contra Acinetobacter baumannii (CIM = 250 µg.mL-1) e atividade fungistática do PBA contra Trichophyton rubrum (CIM = 800 µg.mL-1). Os extratos não apresentaram toxicidade para CMSP e células neoplásicas (IC50 > 100 µg.mL-1). Além disso, o PBO a 100 µg.mL-1 inibiu significativamente as citocinas IFN-γ e IL-17A (p = 0,03). Plectranthus barbatus é um candidato potencial para uso terapêutico devido à sua baixa toxicidade em células humanas saudáveis e exibe atividade de interesse médico como bacteriostática, fungistática e imunomoduladora.

Phytochemical characterization and biological activities of Plectranthus barbatus Andrews / Caracterização fitoquímica e atividades biológicas de Plectranthus barbatus Andrews

Plectranthus barbatus Andrews (Lamiaceae) is widely distributed in the world and has a range of popular therapeutic indications. This work aimed to evaluate the phytochemical characterization of two leaf extracts of P. barbatus, and their antimicrobial, antineoplastic and immunomodulatory potential. After collection, herborization and obtainment of the P. barbatus aqueous extract (PBA) and acetone:water 7:3 P. barbatus organic extract (PBO), the phytochemical characterization was performed by high-performance liquid chromatography (HPLC). The antimicrobial activity was performed to determine the minimum inhibitory concentration (MIC) against eight bacterial strains using the microdilution test and the fungus Trichophyton rubrum by disc diffusion assay and microdilution test. Cytotoxicity was assessed by MTT and trypan blue methods in normal peripheral blood mononuclear cells (PBMCs) at concentrations ranged between 0.1 to 100 µg.mL-¹ and in neoplastic cell lines Toledo, K562, DU-145 and PANC-1 at 1, 10 and 100 µg.mL-¹ . Immunomodulatory activity, was evaluated by sandwich ELISA of proinflammatory cytokines at BALB/c mice splenocytes cultures supernatant. Both extracts presented flavonoids, cinnamic derivatives, steroids and ellagic acid. PBO showed bacteriostatic activity against Acinetobacter baumannii (MIC = 250 µg.mL-¹) clinical isolate and PBA fungistatic activity against Trichophyton rubrum (MIC = 800 µg.mL-¹). The extracts did not exhibit toxicity to PBMCs and neoplastic cells (IC50 > 100 µg.mL-¹). Additionally, PBO at 100 µg.mL-1 significantly inhibited IFN-γ and IL-17A cytokines (p = 0.03). Plectranthus barbatus is a potential candidate for therapeutic use due to its low toxicity in healthy human cells and exhibits biological activities of medical interest as bacteriostatic, fungistatic and immunomodulatory.

Plectranthus barbatus Andrews (Lamiaceae) é amplamente distribuída no mundo e com uma série de indicações terapêuticas populares. Este trabalho teve como objetivo avaliar a caracterização fitoquímica de dois extratos da folha de P. barbatus e seu potencial antimicrobiano, antineoplásico e imunomodulador. Após coleta, herborização e obtenção do extrato aquoso (PBA) e acetona: água 7: 3 (orgânico) (PBO) de P. barbatus, a caracterização fitoquímica foi realizada por cromatografia líquida de alta eficiência (CLAE). A atividade antimicrobiana foi realizada para determinar a concentração inibitória mínima (CIM) contra oito cepas bacterianas usando o teste de microdiluição e o fungo Trichophyton rubrum por ensaio de difusão em disco e teste de microdiluição. A citotoxicidade foi avaliada por métodos MTT e azul de tripan em células normais mononucleares do sangue periférico (CMSP) em concentrações variadas entre 0,1 a 100 µg.mL-¹ e nas linhagens celulares neoplásicas Toledo, K562, DU-145 e PANC-¹ em 1, 10 e 100 µg.mL-¹ . A atividade imunomoduladora foi avaliada por ELISA sanduíche de citocinas pró-inflamatórias em sobrenadante de culturas de esplenócitos de camundongos BALB/c. Ambos os extratos apresentaram flavonoides, derivados cinâmicos, esteróides e ácido elágico. O PBO mostrou atividade bacteriostática contra Acinetobacter baumannii (CIM = 250 µg.mL-¹) e atividade fungistática do PBA contra Trichophyton rubrum (CIM = 800 µg.mL-¹). Os extratos não apresentaram toxicidade para CMSP e células neoplásicas (IC50 > 100 µg.mL-¹). Além disso, o PBO a 100 µg.mL-¹ inibiu significativamente as citocinas IFN-γ e IL-17A (p = 0,03). Plectranthus barbatus é um candidato potencial para uso terapêutico devido à sua baixa toxicidade em células humanas saudáveis e exibe atividade de interesse médico como bacteriostática, fungistática e imunomoduladora.

Phytochemical characterization and biological activities of Plectranthus barbatus Andrews

Abstract Plectranthus barbatus Andrews (Lamiaceae) is widely distributed in the world and has a range of popular therapeutic indications. This work aimed to evaluate the phytochemical characterization of two leaf extracts of P. barbatus, and their antimicrobial, antineoplastic and immunomodulatory potential. After collection, herborization and obtainment of the P. barbatus aqueous extract (PBA) and acetone:water 7:3 P. barbatus organic extract (PBO), the phytochemical characterization was performed by high-performance liquid chromatography (HPLC). The antimicrobial activity was performed to determine the minimum inhibitory concentration (MIC) against eight bacterial strains using the microdilution test and the fungus Trichophyton rubrum by disc diffusion assay and microdilution test. Cytotoxicity was assessed by MTT and trypan blue methods in normal peripheral blood mononuclear cells (PBMCs) at concentrations ranged between 0.1 to 100 µg.mL-1 and in neoplastic cell lines Toledo, K562, DU-145 and PANC-1 at 1, 10 and 100 µg.mL-1 . Immunomodulatory activity, was evaluated by sandwich ELISA of proinflammatory cytokines at BALB/c mice splenocytes cultures supernatant. Both extracts presented flavonoids, cinnamic derivatives, steroids and ellagic acid. PBO showed bacteriostatic activity against Acinetobacter baumannii (MIC = 250 µg.mL-1) clinical isolate and PBA fungistatic activity against Trichophyton rubrum (MIC = 800 µg.mL-1). The extracts did not exhibit toxicity to PBMCs and neoplastic cells (IC50 > 100 µg.mL-1). Additionally, PBO at 100 µg.mL-1 significantly inhibited IFN- and IL-17A cytokines (p = 0.03). Plectranthus barbatus is a potential candidate for therapeutic use due to its low toxicity in healthy human cells and exhibits biological activities of medical interest as bacteriostatic, fungistatic and immunomodulatory.

Resumo Plectranthus barbatus Andrews (Lamiaceae) é amplamente distribuída no mundo e com uma série de indicações terapêuticas populares. Este trabalho teve como objetivo avaliar a caracterização fitoquímica de dois extratos da folha de P. barbatus e seu potencial antimicrobiano, antineoplásico e imunomodulador. Após coleta, herborização e obtenção do extrato aquoso (PBA) e acetona: água 7: 3 (orgânico) (PBO) de P. barbatus, a caracterização fitoquímica foi realizada por cromatografia líquida de alta eficiência (CLAE). A atividade antimicrobiana foi realizada para determinar a concentração inibitória mínima (CIM) contra oito cepas bacterianas usando o teste de microdiluição e o fungo Trichophyton rubrum por ensaio de difusão em disco e teste de microdiluição. A citotoxicidade foi avaliada por métodos MTT e azul de tripan em células normais mononucleares do sangue periférico (CMSP) em concentrações variadas entre 0,1 a 100 µg.mL-1 e nas linhagens celulares neoplásicas Toledo, K562, DU-145 e PANC-1 em 1, 10 e 100 µg.mL-1 . A atividade imunomoduladora foi avaliada por ELISA sanduíche de citocinas pró-inflamatórias em sobrenadante de culturas de esplenócitos de camundongos BALB/c. Ambos os extratos apresentaram flavonoides, derivados cinâmicos, esteróides e ácido elágico. O PBO mostrou atividade bacteriostática contra Acinetobacter baumannii (CIM = 250 µg.mL-1) e atividade fungistática do PBA contra Trichophyton rubrum (CIM = 800 µg.mL-1). Os extratos não apresentaram toxicidade para CMSP e células neoplásicas (IC50 > 100 µg.mL-1). Além disso, o PBO a 100 µg.mL-1 inibiu significativamente as citocinas IFN- e IL-17A (p = 0,03). Plectranthus barbatus é um candidato potencial para uso terapêutico devido à sua baixa toxicidade em células humanas saudáveis e exibe atividade de interesse médico como bacteriostática, fungistática e imunomoduladora.

Toxicological parameters of aqueous residue after using Plectranthus neochilus for 2,4-D phytoremediation.

Phytoremediation is a technique that reduces the impact and environmental toxicity of toxic agents. Plectranthus neochilus, a species of aromatic plant, has already promoted phytoremediation of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). In addition, it was unclear whether the degradation of 2,4-D alone allows for a non-toxic environment (decontamination efficiency). Therefore, the aim of the present study was to verify the changes of the volatile compounds and concentrated essential oil of P. neochilus after phytoremediation of 2,4-D and the subsequent antibacterial activity of this essential oil concentrate. In addition, the toxicity of the plant's tea and the aqueous medium (waste) after the decontamination of 2,4-D was analyzed. The exposure to 2,4-D did not cause many changes in the volatile compounds, nor in the essential oil concentrate from the plant. Therefore, this essential oil concentrate can be used as an antimicrobial after phytoremediation. Regarding the use of this plant in tea form, it was found to be unsafe, even after phytoremediation, as this tea was toxic to the Drosophila melanogaster model (death of up to 100% of flies). The aqueous medium after 2,4-D phytoremediation became less toxic than the initial one (bioassays with Artemia salina and Allium cepa in the waste groups). However, the efficiency of phytoremediation with this plant must be improved. Therefore, we are performing new studies with P. necohilus and 2,4-D in aqueous medium.

Ethnopharmacology, Phytochemistry and Biological Activities of Native Chilean Plants.

The native flora of Chile has unique characteristics due to the geographical situation of the country, with the vast desert in the North, Patagonia in the South, the Andean Mountains on the east and the Pacific Ocean on the west. This exclusivity is reflected in high concentrations of phytochemicals in the fruits and leaves of its native plants. Some examples are Aristotelia chilensis (Molina), Stuntz (maqui), Berberis microphylla G. Forst. (calafate), Peumus boldus Molina (boldo), Ribes magellanicum Poir. (Magellan currant), Ugni molinae Turcz. (murtilla), Rubus geoides Sm. (miñe miñe), Drimys winteri J.R.Forst. & G.Forst. (canelo), Luma apiculata (DC.) Burret (arrayán) distributed throughout the entire Chilean territory. Some of these Chilean plants have been used for centuries in the country's traditional medicine. The most recent studies of phytochemical characterization of parts of Chilean plants show a wide spectrum of antioxidant compounds, phenolic components, terpenoids and alkaloids, which have shown biological activity in both in vitro and in vivo studies. This manuscript covers the entire Chilean territory characterizing the phytochemical profile and reporting some of its biological properties, focusing mainly on antioxidant, anti-inflammatory, antimicrobial, chemopreventive and cytotoxic activity, and potential against diabetes, metabolic syndrome and gastrointestinal disorders.

Gastroprotective effect of the alkaloid boldine: Involvement of non-protein sulfhydryl groups, prostanoids and reduction on oxidative stress.

Boldine is the main alkaloid of Peumus boldus Molina, widely used in the traditional medicine for the treatment of digestive disorders. It is a compound with excellent antioxidant and anti-inflammatory properties already described. Despite the widespread use of P. boldus for digestive disorders treatment, the gastroprotective effect of Boldine remains unknown. Considering the need for new approaches to treat gastric ulcers with fewer side effects than current therapy, this study aimed to investigate the gastroprotective effect of Boldine in mice, as well as the mechanisms underlying this effect. The gastroprotective effect of Boldine was evaluated on gastric ulcer induced by 60% ethanol/0.3 M HCl or indomethacin (100 mg/kg) in mice. Histological analysis and the mucin-like glycoprotein content were evaluated in ethanol-ulcerated tissue, as well as, oxidative stress and inflammatory parameters. The mechanisms involved in the effect of Boldine were evaluated by pretreating mice with NEM (a sulfhydryl group chelator, 10 mg/kg, i.p.), l-NAME (a non-selective nitric oxide synthase inhibitor, 70 mg/kg, i.p.), yohimbine (an alpha-adrenergic receptor antagonist, 2 mg/kg, i.p.) and indomethacin (a cyclooxygenase inhibitor, 10 mg/kg, i.p.). In addition, the in vitro effect of Boldine on H+/K+-ATPase activity was determined. Boldine was able to protect gastric mucosa against the damage induced by ethanol/HCl and indomethacin, as evidenced by reduced lesion area and histological analysis. Moreover, the alkaloid reduced oxidative stress and inflammatory mediators in ethanol-ulcerated tissue, beyond has increased mucin-like glycoprotein amount. Finally, Boldine effect is dependent on non-protein sulfhydryl groups and prostanoids but does not involve the inhibition of H+/K + -ATPase activity, being a promising natural resource for gastric ulcer treatment.

Impacts of Strain Variation on Response to Heat Stress and Boldo Extract Supplementation to Broiler Chickens.

There is increasing interest in the use of natural antioxidant supplements in poultry diets as protection against the adverse effects of heat stress. The potential protective effect of boldo (Peumus boldus molina) leaf extract, which have antioxidant activity, were investigated against the harmful effects of heat stress in two broiler strains. Arbor Acres (AA) and Avian-48 (AV) chicks were divided into thermoneutral (TN) and heat stress (HS) groups and treated with 1 g boldo leaf extract/4 L drinking water during the heat stress period. HS reduced growth performance in both strains. The phagocytic index, phagocytic activity, and eosinophil and lymphocytes counts were significantly elevated in TN and HS AV birds but not altered in AA birds. Boldo extract treatment partially eliminated the previous negative impacts of heat stress. AA chicks were better able to withstand HS than AV chicks. Serum concentrations of total lipids and cholesterol were reduced in HS birds of both strains. Malondialdehyde, superoxide dismutase, and glutathione peroxidase levels were elevated but restored with the administration of boldo leaf extract in HS birds of both strains. Economic parameters were negatively affected by HS but restored to values close to those of the control group in boldo-treated HS birds. In conclusion, the administration of boldo leaf extract in drinking water was effective in neutralizing the harmful effects of heat stress on growth performance, blood indices, and economic parameters and improved the antioxidant defense system in heat-stressed birds.

Immobilization of Aspergillus ficuum tannase in calcium alginate beads and its application in the treatment of boldo (Peumus boldus) tea.

Tannase (tannin acyl hydrolase, E.C. 3.1.1.20) is an enzyme that catalyzes the hydrolysis of ester and depside linkages in hydrolysable tannins such as tannic acid, releasing gallic acid and glucose. It has several commercial applications in food industry, among which are gallic acid production, reduction of tannin content in fruit juices, and preparation of instantaneous tea. In this study we immobilized Aspergillus ficuum tannase in calcium alginate beads and then used it to treat boldo (Peumus boldus) tea. Such a technique allowed entrapping tannase with a 75% efficiency and appreciably increasing its thermal and pH stability compared with the free enzyme. Storage stability and reuse of the immobilized enzyme were very promising, in that about 60% of starting enzyme activity was retained after bead storage for 90 days at 4 °C or after six cycles of use. Boldo tea treatment with immobilized tannase for 120 min at 40 °C led to 31 and 60% removals of tannins and epigallocatechin gallate, an increase of about two orders of magnitude in gallic acid content, 56 and 109% increases in total flavonoids and epigallocatechin contents, a 42.8% increase in antioxidant activity and significant enhancements of tea color, clarity and pH.

The phytoremediation potential of Plectranthus neochilus on 2,4-dichlorophenoxyacetic acid and the role of antioxidant capacity in herbicide tolerance.

The possible phytoremediation capacity of Plectranthus neochilus (boldo) exposed to the commercial pesticide (Aminol) in soil and water through consecutive extractions (days interval) was evaluated. After the exposure period, tea leaves from the plant were analyzed in terms of the presence of 2,4-D, total antioxidant capacity (DPPH), concentration of total polyphenols and flavonoids for plants exposed to soil and water. In water, 2,4-D remained up to 67% in the 60 days of experiment in the control group, which provided the use of two treatment groups with the plant (one group of plants for 30 days and another group in the remaining 30 days in the same system), thus, a decontamination up to 49% of the 2,4-D was obtained in this system with water. In both experiments (soil and water) the 2,4-D was not detected in tea leaves, the reduction of the antioxidant activity, polyphenols and flavonoids of plants exposed to the herbicide was also observed when compared to the non-exposed plants. In tea - plants in water - it was also possible to quantify the phenolic compounds and it was observed that in the group of plants of the first 30 days there was a decrease in caffeic acid and an increase in coumaric and ferulic acids, compared to the group of plants that were not exposed to 2,4-D. In the remaining 30 days with the new seedlings there was a decrease of the coumaric acid and an increase of the caffeic and ferulic acids.

Evaluation of Boldine Activity against Intracellular Amastigotes of Leishmania amazonensis.

Leishmaniasis is a neglected and endemic disease that affects poorest population mainly in developing countries. A lack of adequate and definitive chemotherapeutic agents to fight against this infection has led to the investigation of numerous compounds. The aim of this study was to investigate in vitro activity of boldine against Leishmania amazonensis murine cell infection. Boldine ((S)-2,9-dihydroxy-1,10-dimethoxy-aporphine) is an aporphine alkaloid found abundantly in the leaves/bark of boldo (Peumus boldus Molina), a widely distributed tree native to Chile. The in vitro system consisted of murine macrophage infection with amastigotes of L. amazonensis treated with different concentrations from 50 to 600 µg/ml of boldine for 24 hr. Intracellular parasite destruction was assessed by morphological examination and boldine cytotoxicity to macrophages was tested by the MTT viability assay. When cells were treated with 100 µg/ml of boldine the reduction of parasite infection was 81% compared with untreated cultures cells. Interestingly, boldine-treatment caused a concentration-dependent decrease of macrophage infection that culminated with 96% of reduction when cells were submitted to 600 µg/ml of boldine. Cell cultures exposed to 100 µg/ml of boldine and 300 µg/ml of Glucantime® during 24 hr showed a significant reduction of 50% in parasitized cells compared with cell cultures exposed just to Glucantime®. The study showed that treatment with boldine produces a better effect than treatment with the reference antimonial drug, glucantime, in L. amazonensis infected macrophage. Our results suggest that boldine is a potentially useful agent for the treatment of leishmaniasis.

Hidden Risks of Alternative Medicines: A Case of Boldo-Induced Hepatotoxicity.

The alternative medicines are commonly used, especially herbal ones. Among them, boldo is traditionally used for symptomatic treatment of dyspepsia and mild gastrointestinal spasmodic disorders. Nevertheless, the number of reported cases of possible hepatotoxicity of some of these products has increased, including one report of boldo-induced hepatitis. We present the case of a 72-year-old female patient who has developed jaundice and increased serum levels of liver enzymes, after repeated consumption of boldo leaves infusion, during 2 weeks. After exclusion of common causes of hepatobiliary pathology, boldo-induced hepatotoxicity was considered probable. Interrupting of ingestion led to clinical and laboratorial recovery. This case proves the value of research in the alternative medicines' use. Ingestion of boldo, particularly in elderly patients with biliary tract disorders, may be the cause of otherwise unexplained jaundice or abnormal values of liver enzymes.

Evaluation of Boldine Activity against Intracellular Amastigotes of Leishmania amazonensis

Leishmaniasis is a neglected and endemic disease that affects poorest population mainly in developing countries. A lack of adequate and definitive chemotherapeutic agents to fight against this infection has led to the investigation of numerous compounds. The aim of this study was to investigate in vitro activity of boldine against Leishmania amazonensis murine cell infection. Boldine ((S)-2,9-dihydroxy-1,10-dimethoxy-aporphine) is an aporphine alkaloid found abundantly in the leaves/bark of boldo (Peumus boldus Molina), a widely distributed tree native to Chile. The in vitro system consisted of murine macrophage infection with amastigotes of L. amazonensis treated with different concentrations from 50 to 600 μg/ml of boldine for 24 hr. Intracellular parasite destruction was assessed by morphological examination and boldine cytotoxicity to macrophages was tested by the MTT viability assay. When cells were treated with 100 μg/ml of boldine the reduction of parasite infection was 81% compared with untreated cultures cells. Interestingly, boldine-treatment caused a concentration-dependent decrease of macrophage infection that culminated with 96% of reduction when cells were submitted to 600 μg/ml of boldine. Cell cultures exposed to 100 μg/ml of boldine and 300 μg/ml of Glucantime® during 24 hr showed a significant reduction of 50% in parasitized cells compared with cell cultures exposed just to Glucantime®. The study showed that treatment with boldine produces a better effect than treatment with the reference antimonial drug, glucantime, in L. amazonensis infected macrophage. Our results suggest that boldine is a potentially useful agent for the treatment of leishmaniasis.

Parâmetros de qualidade físico-químicos e avaliação da atividade antioxidante de folhas de Plectranthus barbatus Andr. (Lamiaceae) submetidas a diferentes processos de secagem / Quality of the leaves of Plectranthus barbatus Andr. (Lamiaceae) dried in solar dryer and oven

RESUMO O presente trabalho descreve a composição físico-química, a avaliação da atividade antioxidante pelo método de sequestro de radicais livres DPPH, determinação de flavonoides e de fenóis totais dos extratos etanol, acetona e aquoso de Plectranthus barbatus Andr. (Lamiaceae), desidratadas em secador solar e em estufa de circulação de ar a 60 oC. Os valores de atividade de água encontrados para as duas secagens foram inferiores ao mínimo necessário para o crescimento e produção de toxina de patógenos de importância alimentar. Os resultados das análises físico-químicas demonstraram que ambos os processos mostraram-se eficientes na desidratação de P. barbatus. Os resultados demonstraram que os extratos acetona (estufa) e etanol (estufa e secador solar) foram os que apresentaram maior conteúdo de fenóis totais. O extrato etanólico (estufa) apresentou maior quantidade de flavonoides e melhor potencial antioxidante (IC50 = 75,71 ± 10,57 µg mL-1).

ABSTRACT This paper describes the physicochemical composition, the evaluation of the antioxidant activity by free DPPH radicals using the scavenging method, the determination of flavonoids and total phenolic compounds of ethanol, acetone and aqueous extracts of the medicinal plant Plectranthus barbatus Andr. (Lamiaceae), dehydrated in solar dryer and circulation oven at 60 °C. Water activity rates for two drying methods were below the minimum necessary for growth and toxin production of important food pathogens. Physicochemical results showed that both processes were effective in the dehydration of P. barbatus. The results demonstrated that the acetone (over) and ethanol (over and solar dryer) extracts showed the highest content of total phenols. The ethanol extract (over) showed the highest amount of flavonoids and better antioxidant activity (75.71 ± 10.57 µg L-1).

Variação sazonal na alelopatia de extratos aquosos de Coleus barbatus (A. ) Benth. sobre a germinação e o desenvolvimento de Lactuca sativa L. / Seasonal variation in the allelopathy of aqueous extracts from Coleus barbatus (A. ) Benth. on the germination and development of Lactuca sativa L.

O objetivo deste trabalho foi avaliar o efeito alelopático de extratos de Coleus barbatus sobre a germinação e desenvolvimento de plântulas de alface. Os experimentos foram conduzidos em laboratório, em diferentes concentrações de extratos obtidos de folhas de falso-boldo (0; 7,5; 15; 22,5; 30%), coletadas nas quatro estações do ano, obtidos por trituração, maceração, infusão e decocção. As sementes de alface foram distribuídas sobre placas de petri umidecidas com 10 mL de solução. Os resultados mostraram que os extratos de folhas afetaram a germinabilidade de sementes de alface apenas na concentração de 30% do extrato preparado por decocção de folhas coletadas no inverno. O índice de velocidade de germinação apresentou redução significativa nos extratos triturados preparados no outono e inverno; na maceração de folhas coletadas no verão e outono e no extrato de decocção preparado no inverno. Os extratos estimularam o crescimento da parte aérea das plântulas de alface, ao passo que, o comprimento das raízes foi afetado pelos extratos, ora inibindo, ora estimulando o crescimento das mesmas. Os extratos de folhas de falso-boldo coletadas nas quatro estações do ano apresentaram efeito alelopático sobre a germinação e o desenvolvimento da alface, sendo que estes variaram em função da sazonalidade da coleta, da forma de obtenção dos extratos e das concentrações testadas.

The aim of this study was to evaluate the allelopathic effects of extracts from Coleus barbatus on germination and seedling growth of lettuce. The experiments were conducted in the laboratory using different concentrations (0, 7.5, 15, 22.5, 30%) of aqueous extracts from "falso-boldo" leaves harvested in all four seasons; extracts were obtained by grinding, maceration, infusion and decoction. Seeds were distributed on Petri dishes moistened with 10 mL solution. Results showed that the leaf extracts affected the germination of lettuce seeds only at the concentration of 30% extract prepared by decoction of leaves harvested in the winter. Germination speed index showed significant reduction for ground extracts prepared in the fall and winter, as well as for macerated leaves harvested in the summer and fall and for extracts prepared through decoction in the winter. The extracts stimulated the growth of shoots of lettuce seedlings, whereas root length was affected by the extracts, which either stimulated or inhibited its growth. Extracts of "falso-boldo" leaves harvested in all four seasons had allelopathic effect on germination and development of lettuce, and the latter varied depending on the harvest season, the form of preparing the extracts and the tested concentrations.

Composição do óleo essencial de quatro espécies do gênero Plectranthus / Essential oil composition of four Plectranthus species

O gênero Plectranthus é considerado um dos mais ricos em óleos essenciais dentro da família Lamiaceae, compreendendo muitas espécies com propriedades medicinais. Algumas destas são conhecidas popularmente como boldo, as quais possuem semelhanças taxonômicas e diversas sinonímias, possuindo ações anti-dispépticas, analgésicas e digestivas. O objetivo deste estudo foi avaliar quantitativa e qualitativamente os óleos essenciais presentes nas folhas das espécies P. amboinicus, P. barbatus, P. grandis e P. neochilus. A extração do óleo foi realizada por hidrodestilação, utilizando pentano como solvente extrator, repetida por três vezes para cada uma das espécies. A análise dos componentes dos óleos essenciais das quatro espécies de Plectranthus, através da CG/EM, permitiu identificar 14 componentes químicos, sendo a maioria sesquiterpenos. O trans-cariofileno se apresentou em elevada concentração nos óleos estudados. Alguns componentes químicos demonstraram ser específicos para cada espécie e outros apresentaram ocorrência comum a todas as quatro, possibilitando a diferenciação das mesmas em dois grupos, um formado por P. amboinicus e P. neochilus e o outro por P. grandis e P. barbatus. Conclui-se que as quatro espécies de boldo apresentam diferenças significativas quanto ao teor e à constituição química do óleo essencial.

Plectranthus has been considered one of the richest genera in essential oils within the Lamiaceae family, which includes several species with medicinal properties. Some of them are commonly known as boldo and present taxonomic similarities and several synonymies, with antidyspeptic, analgesic and digestive actions. The aim of this study was to evaluate quantitatively and qualitatively the essential oils from P. amboinicus, P. barbatus, P. grandis and P. neochilus leaves. The oil was extracted by hydrodistillation using pentane as extracting solvent and was repeated three times for each species. The analysis of essential oil components by GC/MS in the four Plectranthus species identified 14 chemical components, mostly sesquiterpenes. High concentration of trans-caryophyllene was found in the studied oils. Some chemical components were specific for each species and other components had common occurrence in all four species, allowing their differentiation into two groups, one composed of P. amboinicus and P. neochilus and another one by P. grandis and P. barbatus. In conclusion, the four boldo species had significant differences as to essential oil yield and chemical composition.

Genetic similarities among four species of the Plectranthus ( L’Hér. ) genus / Similaridade genética de quatro espécies do gênero Plectranthus

The Plectranthus genus comprises several species generally referred to as boldo, which are highly used in popular medicine due to their anti-dyspeptic, analgesic and digestion-stimulating properties. The amount of natural active principles can vary greatly in the related genotypes, which may lead to the inappropriate use of these plants. This work aimed to analyze the interspecific diversity among four species of the Plectranthus genus (P. grandis, P. barbatus, P. neochilus and P. amboinicus) and the intraspecific diversity of P. barbatus collected from different places in southern Brazil, by means of the RAPD technique. A higher genetic similarity was observed between the P. neochilus and P. amboinicus species (80%), followed by P. grandis and P. barbatus (77%). P. barbatus genotypes from Passo Fundo and Porto Alegre showed a genetic similarity which was close to 100%, while the genetic similarity for P. barbatus genotypes from other locations was higher than 96%. Although a low variability among genotypes of this species was found in this study, RAPD markers allowed a clear differentiation among the analyzed genotypes, showing a 53% mean genetic similarity, with a high correlation value (r = 0.99), which proves a high agreement between the genetic similarity and clustering data.

O gênero Plectranthus abrange plantas de diversas espécies, referidas como boldo, que são utilizadas na medicina popular pelas suas propriedades antidispépticas, analgésicas e estimulantes da digestão. Genótipos relacionados podem diferir amplamente na quantidade de princípios ativos naturais, resultando no uso de plantas não-apropriadas à saúde da população. O objetivo do presente estudo foi avaliar a diversidade genética interespecífica de quatro espécies do gênero Plectranthus (P. grandis, P. barbatus, P. neochilus e P. amboinicus) e intraespecífica de P. barbatus, coletadas em diferentes localidades da região Sul do Brasil, por meio da técnica de RAPD (Random Amplified Polymorphic DNA). Foi observada maior similaridade genética entre as espécies P. neochilus e P. amboinicus (80%), seguido de P. grandis e P. barbatus (77%). Genótipos de P. barbatus provenientes de Passo Fundo e Porto Alegre apresentaram similaridade genética próximo a 100%, enquanto nas demais regiões foi superior a 96%. Embora no presente trabalho tenha sido detectada baixa variabilidade entre genótipos desta espécie, a técnica de RAPD permitiu clara separação entre as quatro espécies analisadas, apresentando uma similaridade genética média de 53%, com um valor de correlação alto (r = 0,99), demonstrando elevada representatividade dos dados de similaridade genética com os de agrupamento.

Farmacologia e Toxicologia de Peumus boldus e Baccharis genistelloides / Pharmacology and toxicology of Peumus boldus and Baccharis genistelloides

Um grande número de espécies com uso medicinal tradicional ainda continua sem comprovação da eficácia e da segurança de seu uso. Este artigo apresenta uma pequena revisão sobre os trabalhos publicados com boldo (Peumus boldus) e carqueja (Baccharis genistelloides). Os estudos farmacológicos realizados com P. boldus e B. genistelloides comprovam várias das atividades atribuídas popularmente a esses chás, além de correlacionarem esses efeitos a compostos puros, isolados a partir desses extratos. Já os estudos toxicológicos sugerem que o chá de boldo deve ser consumido com moderação e cuidado, principalmente no primeiro trimestre da gravidez (indícios de teratogenia) e no uso por tempo prolongado (indícios de hepatotoxicidade), enquanto o consumo do chá de carqueja deve ser proibido para gestantes (risco comprovado de aborto) e para pacientes que utilizam drogas para tratamento de problemas pressóricos (ação hipotensora). Estes relatos reforçam a necessidade de um maior conhecimento sobre as plantas medicinais utilizadas popularmente, não apenas para a confirmação das atividades descritas pelo uso tradicional, mas também para que o uso seguro seja estabelecido.

There are a great number of medicinal plants without any scientific confirmation about their efficacy and safety. This paper is a short review about two medicinal plants, "boldo do chile" (Peumus boldus) and "carqueja" (Baccharis genistelloides). Pharmacological studies have confirmed several popular indications for P. boldus and B. genistelloides, besides have established a relationship between isolated compounds from these extracts and the pharmacological effects observed. On the other hand, toxicological researches have pointed out that P. boldus tea should not be consumed during a long period (potential hepatotoxicity) and by pregnant, especially during the first three months. Moreover, B. genistelloides tea must be prohibited for pregnant because of confirmed abortive action, and for patients using medicines for blood pressure disorders. These studies point out the continuous necessity of more studies about medicinal plants; only with this knowledge it will be possible a safe and efficient use.

Stem and leaf anatomy of Plectranthus neochilus Schltr., Lamiaceae

Plectranthus neochilus Schltr. is an aromatic herb named " boldo" or " boldo-gambá" and employed for treating hepatic insufficiency and dyspepsia in folk medicine. This paper has investigated its stem and leaf anatomy, in order to contribute for the medicinal plant identification. The botanical material was prepared according to standard microtechniques. The stem has quadrangular transection and, in secondary growth at the level analyzed, shows uniseriate epidermis and numerous trichomes. The glandular ones are capitate and peltate. The former has short unicellular or long multicellular stalk and uni- or bicellular head. The latter presents short stalk and eight-celled ovoid head. The non-glandular trichomes are multicellular, uniseriate and coated with granular cuticle. It is observed angular collenchyma, cambia forming phloem outward and xylem inward, and perivascular fiber caps next to the phloem. The blade has uniseriate epidermis coated with striate cuticle, diacytic stomata on both surfaces, numerous trichomes similar to the stem ones, and homogeneous mesophyll. The midrib shows one or two collateral bundles and the petiole has many of them distributed as an open arc.

Plectranthus neochilus Schltr. é uma erva aromática denominada boldo ou " boldo-gambá" e empregada no tratamento de insuficiência hepática e dispepsia na medicina popular. Este trabalho investigou a anatomia caulinar e foliar, com a finalidade de contribuir na identificação dessa planta medicinal. O material botânico foi preparado de acordo com microtécnicas usuais. O caule tem secção transversal quadrangular e, em crescimento secundário no nível analisado, exibe epiderme unisseriada e numerosos tricomas. Os tricomas glandulares são capitados e peltados. Os primeiros têm pedicelo curto e unicelular ou longo e pluricelular e cabeça uni ou bicelular. Os peltados apresentam pedicelo curto e cabeça ovóide com oito células. Os tricomas tectores são pluricelulares, unisseriados e recobertos com cutícula granulosa. Observam-se colênquima angular, câmbio vascular formando floema em direção centrífuga e xilema para o centro, e calotas de fibras perivasculares apostas ao floema. A lâmina foliar tem epiderme uniestratificada revestida por cutícula estriada, estômatos diacíticos em ambas as superfícies, numerosos tricomas similares aos do caule e mesofilo homogêneo. A nervura central possui um ou dois feixes vasculares colaterais e o pecíolo apresenta vários feixes colaterais em arco aberto.