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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.

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Plectranthus barbatus, popularly known as Brazilian boldo, is used in Brazilian folk medicine to treat cardiovascular disorders including hypertension. This study investigated the chemical profile by UFLC-DAD-MS and the relaxant effect by using an isolated organ bath of the hydroethanolic extract of P. barbatus (HEPB) leaves on the aorta of spontaneously hypertensive rats (SHR). A total of nineteen compounds were annotated from HEPB, and the main metabolite classes found were flavonoids, diterpenoids, cinnamic acid derivatives, and organic acids. The HEPB promoted an endothelium-dependent vasodilator effect (~100%; EC50 ~347.10 µg/mL). Incubation of L-NAME (a nonselective nitric oxide synthase inhibitor; EC50 ~417.20 µg/mL), ODQ (a selective inhibitor of the soluble guanylate cyclase enzyme; EC50 ~426.00 µg/mL), propranolol (a nonselective α-adrenergic receptor antagonist; EC50 ~448.90 µg/mL), or indomethacin (a nonselective cyclooxygenase enzyme inhibitor; EC50 ~398.70 µg/mL) could not significantly affect the relaxation evoked by HEPB. However, in the presence of atropine (a nonselective muscarinic receptor antagonist), there was a slight reduction in its vasorelaxant effect (EC50 ~476.40 µg/mL). The addition of tetraethylammonium (a blocker of Ca2+-activated K+ channels; EC50 ~611.60 µg/mL) or 4-aminopyridine (a voltage-dependent K+ channel blocker; EC50 ~380.50 µg/mL) significantly reduced the relaxation effect of the extract without the interference of glibenclamide (an ATP-sensitive K+ channel blocker; EC50 ~344.60 µg/mL) or barium chloride (an influx rectifying K+ channel blocker; EC50 ~360.80 µg/mL). The extract inhibited the contractile response against phenylephrine, CaCl2, KCl, or caffeine, similar to the results obtained with nifedipine (voltage-dependent calcium channel blocker). Together, the HEPB showed a vasorelaxant effect on the thoracic aorta of SHR, exclusively dependent on the endothelium with the participation of muscarinic receptors and K+ and Ca2+ channels.

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Some chewing larvae are capable of inducing galls in the host vascular cylinder, e.g. Dasineura sp. (Cecidomyiidae) on Peumus boldus stems. Due to the medicinal and economic importance of P. boldus, the anatomical and functional implications of establishment of Dasineura sp. on P. boldus stems were investigated. We asked if establishment of Dasineura sp. in P. boldus stems induces abnormalities at the cellular and organizational level of the vascular system that increase during gall development in favour of the hydric status of the gall. Anatomical alterations induced in the stems during gall development were determined. Cytohistometric analyses in mature galls were compared to non-galled stems, and water potential and leaf area of non-galled stems were compared with galled stems. Dasineura sp. establishes in the vascular cambium, leading to delignification and rupture of xylem cells, inhibiting formation of phloem and perivascular sclerenchyma. Gall diameter increases together with larval feeding activity, producing a large larval chamber and numerous layers of nutritive tissue, vascular parenchyma, and sclerenchyma. These anatomical alterations do not affect the leaf area of galled stems but favour increased water flow towards these stems. The anatomical alterations induced by Dasineura sp. in P. boldus stems guarantee water and nutrient supply to the gall and larva. After the inducer exits stems, some host branches no longer have vascular connections with the plant body.

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Objectives: the aim of this study was to evaluate the effects of the association of dry extracts of Astragalus membranaceus, Peumus boldus and Curcuma longa in rats with induced diabetes. Methods: After the induction of type 2 diabetes by intraperitoneal streptozotocin, male Wistar rats were randomly assigned to groups (n=6) and treated for 20 days. The extracts were suspended in water and administered through orogastric gavage once daily as described: Group I: healthy control (saline); group II: received Astragalus membranaceus, Peumus boldus and Curcuma longa (400 mg/kg/day of each dry extract); group III: received Astragalus membranaceus, Peumus boldus, Curcuma longa (400 mg/kg/day of each dry extract) and glibenclamide (15 mg/kg/day). Fasting glucose, glucose tolerance, alanine aminotransferase, aspartate aminotransferase and fructosamine were evaluated. Results: Fasting blood glucose and glucose tolerance for groups II and III were influenced by treatments (p<0.05). The extracts did not significantly influence the efficacy of glibenclamide. Conclusion: The results found in this study allow us to consider that it is not possible to conclude that the compounds evaluated are not effective in DM in rats, due to variables such as total treatment period, doses, size of pancreatic injury caused by streptozotocin, and diet profile may have influenced the results. The studied compounds have potential for application in diabetes and further studies should be carried out to adjust the treatment.

Objetivos: avaliar os efeitos da associação de extratos secos de Astragalus membranaceus, Peumus boldus e Curcuma longa em ratos com diabetes induzida. Métodos: Após a indução de diabetes tipo 2 (DM) por estreptozotocina intraperitoneal, ratos Wistar machos foram distribuídos aleatoriamente em grupos (n=6) e tratados por 20 dias. Os extratos foram suspensos em água e administrados por gavagem orogástrica uma vez ao dia conforme descrito: Grupo I: controle saudável (solução salina); grupo II: recebeu Astragalus membranaceus, Peumus boldus e Curcuma longa (400 mg/kg/dia de cada extrato seco); grupo III: receberam Astragalus membranaceus, Peumus boldus, Curcuma longa (400 mg/kg/dia de cada extrato seco) e glibenclamida (15 mg/kg/dia). A glicemia de jejum, tolerância à glicose, alanina aminotransferase, aspartato aminotransferase e frutosamina foram avaliados. Resultados: A glicemia de jejum e a tolerância à glicose para os grupos II e III foram influenciadas pelos tratamentos (p<0,05). Os extratos não influenciaram significativamente na eficácia da glibenclamida. Conclusão: Os resultados encontrados neste estudo permitem considerar que não é possível concluir que os compostos avaliados não são eficazes no DM em ratos, devido às variáveis como tempo total de tratamento, doses e tamanho da lesão pancreática causada por estreptozotocina, além do perfil da dieta, que podem ter influenciado os resultados. Os compostos estudados têm potencial para aplicação em diabetes e mais estudos devem ser realizados para adequar o tratamento.

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Mesmo com a evolução do conhecimento científico, a utilização de plantas medicinais é uma das práticas mais antigas ainda realizadas pelo homem, especialmente pelos habitantes de comunidades e municípios do interior do Brasil, principalmente em regiões com baixos índices de desenvolvimento humano. O objetivo deste trabalho foi realizar um estudo etnobotânico sobre as plantas medicinais utilizadas pelos moradores de um bairro localizado em um município ribeirinho do interior do estado do Amazonas. Participaram do estudo cem indivíduos, e os dados obtidos pela pesquisa foram compilados por meio de um formulário, contendo 14 questões (objetivas e discursivas). Os resultados demonstraram que 95% dos moradores faziam uso de plantas medicinais. Foram citadas 89 espécies, pertencentes a 48 famílias botânicas, com destaque para a Lamiaceae. As plantas mais citadas foram: Plectranthus barbatus (boldo) ­ 6,1%, Citrus sinensis (laranjeira) ­ 5,8% e Allium sativum (alho) ­ 4,7%. No entanto, quando analisado o índice de concordância (porcentagem de uso principal = CUP), a Citrus sinensis (laranjeira) apresentou um CUP de 80,9%, seguida por Plectranthus barbatus (boldo) e Disphania ambrosioides (mastruz), com 68,1% e 61,5%, respectivamente. Com relação ao modo de preparo, 61,1% citaram infusão, e as principais enfermidades tratadas foram as dores de estômago, com 13,1%. É importante enfatizar a necessidade de mais estudos acerca dos reais benefícios dessas ervas, a fim de que a divulgação de tais informações possa complementar o conhecimento empírico já difundido entre a população local. Dessa forma, será possível ampliar o conhecimento etnobotânico como um todo e, consequentemente, promover saúde e bem-estar.

Despite the evolution of scientific knowledge, the use of medicinal plants is one of the oldest practices still used by men and, especially by the inhabitants of communities and municipalities of the interior of Brazil, mainly in regions with low human development rates. The purpose of this work was to perform an ethnobotanical study on medicinal plants used by residents of a neighborhood located in a riverside city in the interior of the state of Amazonas. A total of 100 individuals participated in the study, with data being obtained through the use of a form containing 14 open and closed-ended questions. The results showed that 95% of the residents used medicinal plants. A total of 89 species, belonging to 48 botanical families were mentioned, with emphasis to Lamiaceae. The plants that were most frequently mentioned were Plectranthus barbatus (locally known as boldo) ­ 6.1%; Citrus sinensis (orange tree) ­ 5.8%; and Allium sativum (garlic) ­ 4.7%. However, when analyzing the agreement index (percentage of main use = CUP), Citrus sinensis (orange tree) presented a CUP of 80.9%, followed by Plectranthus barbatus (boldo) and Disphania ambrosioides (Mexican tea), with 68.1 and 61.5%, respectively. In relation to the method of preparation, 61.1% cited infusion, with the main disorder treated being stomachache, with 13.1%. It is important to emphasize the need for further studies on the actual benefits of these herbs so that the dissemination of the information can complement the already widespread empirical knowledge among the local population. Thus, it will be possible to expand the ethnobotanical knowledge as a whole and, consequently, promote health and well-being.

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Peumus boldus is an endemic tree species from Chile whose leaves have been the focus of study for decades given that their infusions are reported to relieve rheumatic symptoms, headache, dyspepsia, urinary tract inflammation, and symptoms of other illnesses. These health properties have been studied mainly using leaves and bark, then it is relevant to know more about these properties in different parts of the plant. Considering the importance of P. boldus fruits in the diet of some rural populations, we analyzed their properties to explore its impact on the Chilean population health. Liquid chromatography and mass spectrometry analysis confirmed the presence of alkaloids such as boldine, although aporphine N-methyl-laurotetanine was the most abundant. In addition, flavonoids catechin, chrysin and quercetin were also found in the extract. Cytotoxicity and anti-inflammatory activities of the fruit extract were invitro tested by using a murine macrophage cell model, observing that a diluted fraction of the extract was not cytotoxic, but showed anti-inflammatory activity, which is likely attributed to antioxidants activities. By means of quantum chemical calculations, we calculated the redox potential of the respective alkaloids and flavonoids found in the extract. Results suggest a synergistic effect between alkaloids and flavonoids, where boldine and N-methyl-laurotetanine showed similar antioxidant properties. Finally, we present a description of the oxidation mechanisms for both groups of molecules which will sustain P. boldus fruit biological properties, in order to give this kind of fruits scientific value focusing on human health.

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Chrysomya megacephala (Fabricius, 1794) is a vector of enteric bacteria, protozoa, helminths, and viruses. These Diptera can also be responsible for secondary myiasis in several animal species. Therefore, it is easy to understand the relevance of studies focusing on C. megacephala dissemination control. The employment of essential oils as natural insecticides must be considered as a promising alternative for the replacement of synthetic insecticides. In this context, the essential oil obtained from Chilean boldo leaves should be highlighted. The aim of the present work was to assess the insecticidal activity of Chilean boldo essential oil against C. megacephala blowflies in different life stages (larva, pupa, and adult). The essential oils were extracted from commercial samples of Chilean boldo leaves by hydrodistillation and were mixed to produce a pool that was employed in the study. Gas chromatographic techniques were used to enable the identification and quantification of the pool's components. Larvae, pupae, and adult insects of C. megacephala were exposed (topical application) to different concentrations of this essential oil pool. After that, the larvicidal, pupicidal, and insecticidal actions of the oil were tested. Its toxicity might be associated with compounds such as eucalyptol, linalool, α-pinene, limonene, and ascaridole, either acting alone or by synergic effects. Interestingly, the pupae appeared to be stronger than the larvae and adult insects, needing higher doses of essential oil to be killed. The oil's toxic effects could be useful to control C. megacephala dissemination in all of its development phases.

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Chilean boldo (Peumus boldus Molina) is the boldo species most consumed around the world. Digestive and hepatobiliary disorders represent the main targets of its action. This work aims to characterize the volatile chemical composition, toxicological, and antioxidant potentials of the essential oils and teas of commercial samples of Chilean boldo packed on sachets [Group 1 (G1): five samples] or in plastic bags [Group 2 (G2): five samples]. Fifty-three compounds have been identified in the essential oils of commercial samples of Chilean boldo from Brazil, while only twelve compounds have been found in the volatile fraction of their infusions. Terpineol, 1,8-cineole, and p-cymene are the major compounds of essential oils. Terpineol is also the major compound of the volatile fraction of teas, followed by limonene dioxide. The presence in all samples of the chemical markers p-cymene, 1,8-cineole, ascaridole, and boldine suggests that they are genuine. The teas offer a better antioxidant capacity than essential oils, thereby indicating that antioxidant activity is concentrated in the non-volatile fraction of these herbs. All LD50 values estimated for the essential oils are below 200 ppm, thus indicating that the oils are highly cytotoxic. G1 and G2 appear to be very similar with respect to all the parameters analyzed. This similarity may indicate a single source for these products.

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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.

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