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Secondary metabolites from fungi have become a major source of chemical innovation in programs searching for lead molecules with bioactivities, especially over the last 50 years. In this review, we discuss the fundamental considerations in the discovery of molecules for agricultural and medicinal uses. This group of organisms possesses a strong potential for scientific and industrial communities. Recently, the incorporation of new technologies for the artificial cultivation of fungi and the use of better equipment to isolate and identify active metabolites has allowed the discovery of leading molecules for the design of new and safer drugs and pesticides. The geographical region including the Patagonian Andes mountains harbors a wide diversity of fungi, many of them still unknown and so far associated with Chilean-Argentinian Andean endemic forests. There have been very few chemical studies of the fungi located in this region. However, those few studies have allowed the discovery of new molecules. We argue that the richness of fungal biodiversity in this region offers an interesting source for the discovery of bioactive molecules for the basic and applied sciences.

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It is reported in this study the effect of isolates from leaves of Aristotelia chilensis as inhibitors of acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and tyrosinase enzymes. The aim of the paper was to evaluate the activity of A. chilensis towards different enzymes. In addition to pure compounds, extracts rich in alkaloids and phenolics were tested. The most active F5 inhibited AChE (79.5% and 89.8% at 10.0 and 20.0 µg/mL) and against BChE (89.5% and 97.8% at 10.0 and 20.0 µg/mL), showing a strong mixed-type inhibition against AChE and BChE. F3 (a mixture of flavonoids and phenolics acids), showed IC50 of 90.7 and 59.6 µg/mL of inhibitory activity against AChE and BChE, inhibiting the acetylcholinesterase competitively. Additionally, F3 showed and high potency as tyrosinase inhibitor with IC50 at 8.4 µg/mL. Sample F4 (anthocyanidins and phenolic composition) presented a complex, mixed-type inhibition of tyrosinase with a IC50 of 39.8 µg/mL. The findings in this investigation show that this natural resource has a strong potential for future research in the search of new phytotherapeutic treatments for cholinergic deterioration ailments avoiding the side effects of synthetic drugs. This is the first report as cholinesterases and tyrosinase inhibitors of alkaloids and phenolics from A. chilensis leaves.

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The effects of phytochemicals occurred in fractions and extracts of fruits of "Maqui-berry" (Aristotelia chilensis), on the expression of cyclooxygenase-2 (COX-2), inducible-nitric oxide synthases (iNOS) and the production of proinflammatory mediators were investigated in lipopolysaccharide (LPS)-activated murine macrophage RAW-264 cells, as well as their antioxidant activities. The MeOH extract (A), acetone/methanol extract (B), fractions F3, F4, subfractions (SF4-SF6, SF7, SF8-SF10, SF11-SF15, SF16-SF20), quercetin, gallic acid, luteolin, myricetin, mixtures M1, M2 and M3 exhibited potent anti-inflammatory and antioxidant activities. The results indicated that anthocyanins, flavonoids and its mixtures suppressed the LPS induced production of nitric oxide (NO), through the down-regulation of iNOS and COX-2 protein expressions and showed a potent antioxidant activity against SOD, ABTS, TBARS, ORAC, FRAP and DCFH. The inhibition of enzymes and NO production by selected fractions and compounds was dose-dependent with significant effects seen at concentration as low as 1.0-50.0 (ppm) and 5.0-10.0 µM, for samples (extracts, fractions, subfractions and mixtures) and pure compounds, respectively. Thus, the phenolics (anthocyanins, flavonoids, and organic acids) as the fractions and mixtures may provide a potential therapeutic approach for inflammation associated disorders and therefore might be used as antagonizing agents to ameliorate the effects of oxidative stress.

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Ultraviolet radiation (UVR) is involved in both sunburn and the development of skin cancer, which has a high incidence worldwide. Strategies to reduce these effects include the use of photoprotective substances. The aim of this work was to investigate the photoprotective effect of verbascoside isolated from the methanolic extract of Buddleja cordata (BCME) in SKH-1 mice exposed to acute and chronic UV-B radiation. The mouse dorsal area was evaluated macroscopically and microscopically for diagnosis; verbascoside penetration into mouse skin was investigated in vivo by the tape stripping method. After acute UV-B exposure, 100 percent of irradiated mice that had been protected with verbascoside showed no signs of sunburn or of inflammatory processes. After chronic exposure, 100 percent of unprotected mice showed skin carcinomas; in contrast, in mice topically treated with either BCME or verbascoside, the presence of lesions was decreased by 90 percent. These results prove that verbascoside penetrates through the skin of mice and suggest that verbascoside and BCME may potentially prevent photodamage on mice’s skin after acute and chronic UVR exposure.

La radiación ultravioleta (RUV) provoca quemaduras solares y el desarrollo de cáncer de piel. El objetivo de este trabajo fue investigar el efecto fotoprotector del verbascósido obtenido del extracto metanólico de Buddleja cordata (EMBC) en ratones SKH-1 expuestos a RUV-B de manera aguda y crónica. El diagnóstico histológico se llevó a cabo en la piel de la zona dorsal de los ratones. La penetración del verbascósido fue cuantificada mediante la técnica de la cinta adhesiva. En el experimento agudo, el 100 por ciento de los ratones protegidos con verbascósido no evidenciaron signos de quemadura ni procesos inflamatorios. En el experimento crónico los ratones sin protección e irradiados presentaron carcinomas cutáneos. En contraste en los ratones protegidos con EMBC o verbascósido las lesiones disminuyeron un 90 por ciento en ambos grupos. El verbascósido penetró en la piel del ratón. Los resultados sugieren que el EMBC y el verbascósido previenen el fotodaño en la piel de ratones expuestos de forma aguda o crónica a la RUV.

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Leaf explants of Maytenus boaria were induced towards callus tissue culture with different mixture of cytokinins and auxins. MeOH extract of callus was partitioned with AcOEt and water, and through repeated chromatography procedures were isolated and identified, four triterpenes and three beta-agarofuran sesquiterpenes.

Explantes de hojas de Maytenus boaria fueron inducidos a formar callos mediante diferentes mezclas de citoquininas y auxinas. Un extracto metanólico de los callos fue fraccionado con AcOEt y agua, y mediante repetidas cromatografías fueron aislados e identificados siete compuestos, cuatro triterpenos y 3 sesquiterpenos del tipo agarofurano.

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In México, Pachyrhizus erosus (Fabaceae) commonly called "jícama", is widely known for its edible tubers. It is cultivated since the pre-Columbian period, and the powdered seeds have been used for the treatment of mange, lice, and fleas, due to their content of rotenone, a well-known insecticidal compound. On the other hand, P. ferrugineus, a wild species can only be found in the Tropical Forests, and has no commercial value. It is known that plants release volatile organic compounds (VOCs) showing qualitative and quantitative differences if are wild or cultivated. VOCs are also involved as repelling or attracting chemical signals to insect herbivores, and their natural enemies. Until now, the VOCs of the leaves of P. erosus and P. ferrugineus have not been investigated. In the present contribution the VOCs of both species were characterized by headspace solid-phase (HS-SPME) extraction and gas chromatography-mass spectrometry (GC-MS-TOF). In P. erosus 21 VOCs were found, being the most abundant: cyclohexanone (32.8 percent), 3-hexen-1-ol (Z) (32.7 percent), 3-hexenal (Z) (10.5 percent). The majoritarian compounds were C6 or C5 derivatives In P. ferrugineus, the most abundant VOCs were: 5-hexene-1-ol acetate (51.5 percent), undecanal (22.4 percent), 2-hepten-1-al (14.5 percent). The majoritarian compounds were C6, C7 or C11 derivatives.

En México, Pachyrhizus erosus (Fabaceae) es llamada comúnmente "jícama" y es conocida por sus tubérculos comestibles. Se ha cultivado desde el período pre-Colombino y las semillas se han utilizado para el tratamiento tópico de la sarna, piojos, pulgas; las semillas contienen rotenona, un compuesto insecticida. Por otra parte, P. ferrugineus solo está presente en estado silvestre en los bosques tropicales y carece de valor comercial. Se sabe que las plantas liberan compuestos orgánicos volátiles (COV) y muestran diferencias cualitativas y cuantitativas dependiendo, si son silvestres o cultivadas. Los COV también son señales químicas atrayentes o repelentes de los insectos herbívoros y a sus enemigos naturales. Hasta ahora, los COV en las hojas de P. erosus y P. ferrugineus no han sido investigados. En el presente trabajo, los COV se identificaron mediante la microextracción (HS-SPME) en fase sólida, e identificados por cromatografía de gases acoplada a espectrometría de masas (GC-MS-TOF). En P. erosus se encontraron 21 COV, siendo los más abundantes: ciclohexanona (32.8 por ciento), 3-hexen-1-ol (Z) (32.7 por ciento) y 3-hexenal (Z) (10.5 por ciento). Los compuestos mayoritarios son C6 y C5. En P. ferrugineus los más abundantes fueron: 5-hexen-1-ol acetato (51.5 por ciento), undecanal (22.4 por ciento) y 2-hepten-1-al (14.5 por ciento). Los compuestos mayoritarios son C6, C7 o C11.

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Pedalitin, isolated from the aerial part of Rabdosia japonica (Labiatae), inhibited soybean lipoxygenase-1 (EC 1.13.11.12, Type I) with an IC50 of 152.5 uM. The progress curves for an enzyme reaction, pedalitin inactivate the lipoxygenase-1 in a time dependent, irreversible manner, exhibiting kinetics with a kinact/KI of 59.6 +/- 10 mM-1min-1. In the pseudoperoxidase activity, pedalitin is very slowly oxidized by the soybean lipoxygenase-1 catalyzed decomposition of lipid hydroperoxides.

Pedalitina, aislada de las partes aereas de Rabdosia japonica inhibió a la lipooxigenasa-1 (EC 1.13.11.12 tipo I) con un IC50 de 152.5 uM. La curva de progreso para una acción enzimática, pedalitina inactivó a la lipooxigenasa-1 de una manera dependiente del tiempo, de una manera irreversible, exhibiendo una cinética con una kinact/KI de 59.6 +/- mM-1min-1. En la actividad pseudoperoxidasa, pedalitina es oxidada lentamente por la descomposición de la lípido hidroperóxido de la lipooxigenasa-1 de poroto de soya.

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Natural cholinesterase inhibitors have been found in many biological sources. Nine compounds with agarofuran (epoxyeudesmane) skeletons were isolated from seeds and aerial parts of Maytenus disticha and Euonymus japonicus. The identification and structural elucidation of compounds were based on spectroscopic data analyses. All compounds had inhibitory acetylcholinesterase (AChE) activity. These natural compounds, which possessed mixed or uncompetitive mechanisms of inhibitory activity against AChE, may be considered as models for the design and development of new naturally occurring drugs for management strategies for neurodegenerative diseases. This is the first report of these chemical structures for seeds of M. disticha.

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In addition to eucalyptin the methanol extract from leaves of Eucalyptus citriodora (Myrtaceae) afforded the known compounds apigenin, chrysin, luteolin, naringenin, quercetin; together with betulinic acid, oleanolic, ursolic acid, and two remaining complex mixtures of unidentified flavonoids and triterpenes. These compounds together with triterpenes mixtures, hexane and ethyl acetate extracts showed antifeedant, insecticidal and insect growth regulatory activities against fall armyworm [Spodoptera frugiperda JE Smith (Lepidoptera: Noctuidae)] an important pest of corn, and yellow mealworm [Tenebrio molitor (Coleoptera:Tenebrionidae)] a pest of stored grains. The most active compounds were chrysin, eucalyptin, quercetin, luteolin, and betulinic and oleanolic acids and the mixtures of flavonoids and triterpenes (M1 and M2). These compounds and mixtures had IGR activity between 0.2 to 5.0 ug/mL and insecticidal effects between 5.0 and 10.0 μg/mL.The extracts were insecticidal to larvae, with lethal doses between 20-100 ug/mL. These compounds appear to have selective effects on the pre-emergence metabolism of the Lepidoptera, since in all treatments of the larvae of S. frugiperda the pupation was shortened and this process showed precociousness in relation to control. Thus, these substances may be useful as potential natural insecticidal agents.

Extracto metanolico de hojas de Eucalyptus citriodora (Myrtaceae) proporcionó además de eucalyptin, flavonoides tales como apigenina, crisina, luteolina, naringenina, quercetina; los triterpenos, ácido oleanólico, ácido ursólico betulínico, y dos mezclas complejas de flavonoides y triterpenos no identificados M1 y M2. Los flavonoides, triterpenos y mezclas de triterpenos, extractos de acetato de etilo y hexano mostraron efectos antialimentarios, insecticida y actividad reguladora de crecimiento (IGR) frente al gusano cogollero [Spodoptera frugiperda JE Smith (Lepidoptera: Noctuidae)], una plaga importante del maíz y frente al gusano de la harina [Tenebrio molitor (Coleoptera: Tenebrionidae)], una plaga de los granos almacenados. Los compuestos más activos fueron crisina, eucalyptin, quercetina, luteolina, ácido betulínico y ácido oleanólico y las mezclas de flavonoides y triterpenos (M1 y M2). Estos compuestos y mezclas mostraron actividad IGR entre 0,2 y 5,0 ug/mL y efectos insecticidas entre 5,0 y 10,0 μg/mL. Los extractos mostraron carácter insecticida para las larvas a dosis letales entre 20-100 ug/mL. Estas muestras parecen tener efectos selectivos sobre el metabolismo de pre-emergencia de los lepidópteros, ya que en todos los tratamientos de las larvas de S. frugiperda el tiempo de la pupación se acortó; este proceso muestra precocidad en relación con el control, las substancias ensayadas en este trabajo pueden ser útiles como potenciales agentes insecticidas naturales.

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Persistent application of pesticides often leads to accumulation in the environment and to the development of resistance in various organisms. These chemicals frequently degrade slowly and have the potential to bio-accumulate across the food chain and in top predators. Cancer and neuronal damage at genomic and proteomic levels have been linked to exposure to pesticides in humans. These negative effects encourage search for new sources of biopesticides that are more "environmentally-friendly" to the environment and human health. Many plant or fungal compounds have significant biological activity associated with the presence of secondary metabolites. Plant biotechnology and new molecular methods offer ways to understand regulation and to improve production of secondary metabolites of interest. Naturally occurring crop protection chemicals offer new approaches for pest management by providing new sources of biologically active natural products with biodegradability, low mammalian toxicity and environmentally-friendly qualities. Latin America is one of the world's most biodiverse regions and provide a previously unsuspected reservoir of new and potentially useful molecules. Phytochemicals from a number of families of plants and fungi from the southern Andes and from Mexico have now been evaluated. Andean basidiomycetes are also a great source of scientifically new compounds that are interesting and potentially useful. Use of biopesticides is an important component of integrated pest management (IPM) and can improve the risks and benefits of production of many crops all over the world.

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