Antimicrobial Activity and Phytochemical Characterization of Baccharis concava Pers., a Native Plant of the Central Chilean Coast.

Few sclerophyllous plants from the central coast of Chile have been systematically studied. This work describes the phytochemical composition and antimicrobial properties of Baccharis concava Pers. (sin. B. macraei), a shrub found in the first line and near the Pacific coast. B. concava has been traditionally used by indigenous inhabitants of today's central Chile for its medicinal properties. Few reports exist regarding the phytochemistry characterization and biological activities of B. concava. A hydroalcoholic extract of B. concava was prepared from leaves and small branches. Qualitative phytochemical characterization indicated the presence of alkaloids, steroids, terpenoids, flavonoids, phenolic, and tannin compounds. The antimicrobial activity of this extract was assessed in a panel of microorganisms including Gram-positive bacteria, Gram-negative bacteria, and pathogenic yeasts. The extract displayed an important antimicrobial effect against Gram-positive bacteria, Candida albicans, and Cryptococcus neoformans but not against Gram-negatives, for which an intact Lipopolysaccharide is apparently the determinant of resistance to B. concava extracts. The hydroalcoholic extract was then fractionated through a Sephadex LH-20/methanol-ethyl acetate column. Afterward, the fractions were pooled according to a similar pattern visualized by TLC/UV analysis. Fractions obtained by this criterion were assessed for their antimicrobial activity against Staphylococcus aureus. The fraction presenting the most antimicrobial activity was HPLC-ESI-MS/MS, obtaining molecules related to caffeoylquinic acid, dicaffeoylquinic acid, and quercetin, among others. In conclusion, the extracts of B. concava showed strong antimicrobial activity, probably due to the presence of metabolites derived from phenolic acids, such as caffeoylquinic acid, and flavonoids, such as quercetin, which in turn could be responsible for helping with wound healing. In addition, the development of antimicrobial therapies based on the molecules found in B. concava could help to combat infection caused by pathogenic yeasts and Gram-positive bacteria, without affecting the Gram-negative microbiota.

Anti-Inflammatory Chilean Endemic Plants.

Medicinal plants have been used since prehistoric times and continue to treat several diseases as a fundamental part of the healing process. Inflammation is a condition characterized by redness, pain, and swelling. This process is a hard response by living tissue to any injury. Furthermore, inflammation is produced by various diseases such as rheumatic and immune-mediated conditions, cancer, cardiovascular diseases, obesity, and diabetes. Hence, anti-inflammatory-based treatments could emerge as a novel and exciting approach to treating these diseases. Medicinal plants and their secondary metabolites are known for their anti-inflammatory properties, and this review introduces various native Chilean plants whose anti-inflammatory effects have been evaluated in experimental studies. Fragaria chiloensis, Ugni molinae, Buddleja globosa, Aristotelia chilensis, Berberis microphylla, and Quillaja saponaria are some native species analyzed in this review. Since inflammation treatment is not a one-dimensional solution, this review seeks a multidimensional therapeutic approach to inflammation with plant extracts based on scientific and ancestral knowledge.

Improvement of endothelial function by Gunnera tinctoria extract with antioxidant properties.

BACKGROUND: Gunnera tinctoria has been collected by Mapuche-Pewenche people for food and medicinal purposes. The high polyphenol content of methanolic extract from G. tinctoria leaves with chemical constituents such as ellagic acid and quercetin derivatives suggests its application to prevent endothelial dysfunction and oxidative stress. The aim of this study was to provide evidence of the protective effect of this extract on endothelial function by reducing oxidative stress induced by high D-glucose and H2O2, as well as by stimulating nitric oxide (NO) levels in human umbilical vein endothelial cells (HUVECs). RESULTS: A methanolic extract with a high content of polyphenols (520 ± 30 mg gallic acid equivalents/g dry extract) was obtained from G. tinctoria leaves. Its main constituent was ellagic acid. The results of Ferric reducing antioxidant power and 2,2-diphenyl-1-picrylhydrazyl radical scavenging assays of the extract confirmed its antioxidant activity by inhibition pathway of radical species. The incubation of HUVECs with the extract decreased the apoptosis and reactive oxygen species (ROS) synthesis induced by high extracellular concentration of D-glucose or hydrogen peroxide. The extract increased endothelial NO levels and reduced vasoconstriction in human placental vessels. CONCLUSIONS: This study provides evidence about the antioxidant and endothelial protective properties of methanolic G. tinctoria leaf extract. The extract improves the availability of NO in HUVECs, inhibiting the production of ROS and vasoconstriction.

A Novel Hydrocolloid Film Based on Pectin, Starch and Gunnera tinctoria and Ugni molinae Plant Extracts for Wound Dressing Applications.

BACKGROUND: The biodegradable and biocompatible nature of pectin-based films is of particular interest in wound dressing applications, due to its non-toxicity, pH-sensitivity and gelling activity. An approach to improve the mechanical properties, the release profile of bioactive compounds as well as the performance in wet environments of pectin-based films is mixing with other biopolymers. OBJECTIVE: To prepare hydrocolloid films based on crosslinked pectin / starch blend loaded with bioactive extracts from leaves of G. tinctoria and U. molinae with controlled release of bioactive compounds and healing property. METHODS: The hydrocolloid films were characterized by FTIR, SEM, and TGA-FTIR techniques and their tensile properties, water uptake, and polyphenolic release profile in aqueous media were evaluated. The dermal anti inflammatory activity of the hydrocolloid films was assessed by the mouse ear inflammation test. The wound healing property of the loaded hydrocolloid films was explored in a rat model and in a clinical trial (sacrum pressure ulcer). RESULTS: The films showed an adequate water-uptake capacity between 100-160%. The release of active compounds from the hydrocolloid films followed the Korsmeyer-Peppas equation. The mechanical properties of hydrocolloid films were not affected by the plant extracts within the concentration range used. The incorporation of the bioactive extracts in the polysaccharide films inhibited the topical edematous response by about 50%. The topical application of the loaded hydrocolloid film on the pressure ulcer is completely closed after 17 days without showing any adverse reaction. CONCLUSION: A novel hydrocolloid matrix was produced from crosslinked starch-pectin, which exhibited suitable chemical-physical properties to be used as a carrier of plant extracts with wound healing properties.

Improvement of endothelial function by Gunnera tinctoria extract with antioxidant properties

BACKGROUND: Gunnera tinctoria has been collected by Mapuche-Pewenche people for food and medicinal purposes. The high polyphenol content of methanolic extract from G. tinctoria leaves with chemical constituents such as ellagic acid and quercetin derivatives suggests its application to prevent endothelial dysfunction and oxidative stress. The aim of this study was to provide evidence of the protective effect of this extract on endothelial function by reducing oxidative stress induced by high D-glucose and H2O2, as well as by stimulating nitric oxide (NO) levels in human umbilical vein endothelial cells (HUVECs). RESULTS: A methanolic extract with a high content of polyphenols (520 ± 30 mg gallic acid equivalents/g dry extract) was obtained from G. tinctoria leaves. Its main constituent was ellagic acid. The results of Ferric reducing antioxidant power and 2,2-diphenyl-1-picrylhydrazyl radical scavenging assays of the extract confirmed its antioxidant activity by inhibition pathway of radical species. The incubation of HUVECs with the extract decreased the apoptosis and reactive oxygen species (ROS) synthesis induced by high extracellular concentration of D-glucose or hydrogen peroxide. The extract increased endothelial NO levels and reduced vasoconstriction in human placental vessels. CONCLUSIONS: This study provides evidence about the antioxidant and endothelial protective properties of methanolic G. tinctoria leaf extract. The extract improves the availability of NO in HUVECs, inhibiting the production of ROS and vasoconstriction.

Antihyperalgesic Activity of Quillaic Acid Obtained from Quillaja Saponaria Mol.

BACKGROUND: Quillaja saponaria Mol. bark contains a high concentration of triterpene saponins that have been used for centuries as a cleansing, antiinflammatory and analgesic agent in Chilean folk medicine. In earlier studies, in mice, both the anti-inflammatory as well as the antinociceptive effect of the major sapogenin, quillaic acid have been demonstrated (QA). OBJECTIVE: To determine the antihyperalgesic effect of QA one and seven days after itpl administration of complete Freund's adjuvant (CFA) in male mice using the hot plate test in the presence of complete Freund's adjuvant (HP/CFA) as an acute and chronic skeletal muscle pain model. METHODS: The present study evaluated the antihyperalgesic activity of QA against acute and chronic skeletal muscle pain models in mice using the hot plate test in the presence of complete Freund's adjuvant (HP/CFA), at 24 h (acute assay) and 7 days (chronic assay) , with dexketoprofen (DEX) as the reference drug. RESULTS: In acute and chronic skeletal muscle pain assays, QA at 30 mg/kg ip elicited its maximal antihyperalgesic effects (65.0% and 53.4%) at 24 h and 7 days, respectively. The maximal effect of DEX (99.0 and 94.1 at 24 h and 7 days, respectively) was induced at 100 mg/kg. CONCLUSION: QA and DEX elicit dose-dependent antihyperalgesic effects against acute and chronic skeletal muscle pain, but QA is more potent than DEX in the early and late periods of inflammatory pain induced by CFA.

Topical anti-inflammatory activity of quillaic acid from Quillaja saponaria Mol. and some derivatives.

OBJECTIVES: Quillaic acid is the major aglycone of the widely studied saponins of the Chilean indigenous tree Quillaja saponaria Mol. The industrial availability of quillaja saponins and the extensive functionalization of this triterpenoid provide unique opportunities for structural modification and pose a challenge from the standpoint of selectivity in regard to one or the other secondary alcohol group, the aldehyde, and the carboxylic acid functions. The anti-inflammatory activity of this sapogenin has not been studied previously and it has never been used to obtain potential anti-inflammatory derivatives. METHODS: A series of quillaic acid derivatives were prepared and subjected to topical assays for the inhibition of inflammation induced by arachidonic acid or phorbol ester. KEY FINDINGS: Quillaic acid exhibited strong topical anti-inflammatory activity in both models. Most of its derivatives were less potent, but the hydrazone 8 showed similar potency to quillaic acid in the TPA assay. CONCLUSIONS: The structural modifications performed and the biological results suggest that the aldehyde and carboxyl groups are relevant to the anti-inflammatory activity in these models.

Antinociceptive activity of Quillaja saponaria Mol. saponin extract, quillaic acid and derivatives in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Quillaja saponaria bark contains a high percentage of triterpene saponins and has been used for centuries as a cleansing and analgesic agent in Chilean folk medicine. AIM OF THE STUDY: The topical and systemic analgesic effects of a commercial partially purified saponin extract, 3ß,16α-dihydroxy-23-oxoolean-12-en-28-oic acid (quillaic acid), methyl 3ß,16α-dihydroxy-23-oxoolean-12-en-28-oate and methyl 4-nor-3,16-dioxoolean-12-en-28-oate. MATERIALS AND METHODS: The samples were assessed in mice using the topical tail-flick and i.p. hot-plate tests, respectively. RESULTS: All the samples showed activity in both analgesic tests in a dose-dependent manner. The most active against tail flick test was commercial partially purified saponin extract (EC50 27.9 mg%, w/v) and more than the ibuprofen sodium. On hot-plate test, methyl 4-nor-3, 16-dioxoolean-12-en-28-oate was the most active (ED50 12.2 mg/kg) and more than the ibuprofen sodium. CONCLUSIONS: The results of the present study demonstrated that Quillaja saponaria saponins, quillaic acid, its methyl ester, and one of the oxidized derivatives of the latter, elicit dose-dependent antinociceptive effects in two murine thermal models.

Obtención de derivados de ácido quillaico a partir de Quillaja saponaria: evaluación de la actividad antiinflamatoria tópica y oral / Obtaining quillaic acid derivatives from Quillaja saponaria: evaluation of topical and oral anti-inflammatory activity

Quillaja saponaria Mol. es una especie nativa de Chile, empleada desde tiempos ancestrales para el tratamiento de artritis y dolores dentales. Desde el punto de vista químico las saponinas del quillay han sido ampliamente estudiadas y actualmente se comercializan extractos de la biomasa de quillay, para elaborar saponinas de diversas calidades empleadas en la industria farmacéutica y alimentaria. Sin embargo, se conoce poco acerca de la química de la sapogenina principal (ácido quillaico), así como de la farmacología de esta sapogenina aislada. Estos argumentos brindaron la oportunidad de llevar a cabo una investigación orientada hacia la modificación hemisintética de este producto natural y el estudio de su actividad antiinflamatoria tópica y oral in vivo. El objetivo general de este trabajo fue obtener el ácido quillaico a partir de un extracto acuoso de Quillaja sapoaniaria Mol. y derivados a partir de la modificación estructural del ácido quillaico; así como evaluar la actividad antiinflamatoria tópica de los compuestos obtenidos. Para ello se emplearon reacciones que implicaron reducciones, oxidaciones y sustituciones de grupos, fundamentalmente en los anillos A, C y D de la molécula de ácido quillaico. Cada uno de los compuestos aislados fue caracterizado estructuralmente mediante técnicas espectroscópicas y espectrofotométricas. Para evaluar la actividad antiinflamatoria in vivo se empleó el ensayo del edema inducido en la oreja de ratón, tras la administración de AA y/o TPA. En ambos ensayos el grupo de animales tratados con las muestras a evaluar estuvo constituido por 8 animales, los que recibieron una dosis única de cada una de las muestras. Se emplearon dosis de los compuestos aislados equimolares a las dosis de los fármacos de referencia, indometacina y nimesulida. Además se desarrollaron dos formulaciones en base a ácido quillaico al 8%, las cuales fueron evaluadas mediante el ensayo antiinflamatorio descrito anteriormente. Conjuntamente con el ácido quillaico se aisló y caracterizó otra genina de este extracto: el ácido fitolacagénico. Se obtuvieron derivados de ácido quillaico modificando principalmente el grupo hidroxilo adicional en el C-16 y en el grupo aldehído presente en el C-4 en lugar de un metilo. Se demostró la actividad anti inflamatoria tópica del ácido quillaico frente a inflamación inducida por TPA y/o AA. La actividad antiinflamatoria fue dosis dependiente frente a AA con un efecto máximo de 92,1 %, comparado con el fármaco de referencia nimesulida. El ácido quillaico también presentó actividad dosis dependiente frente a TPA (62,2%). Ambos efectos son estadísticamente significativos. El extracto de saponinas totales (100 Q) no presentó actividad tópica en la inflamación inducida por TPA. Por el contrario, se puede concluir que hubo un efecto pro-inflamatorio. Frente a AA, el 100Q mostró un efecto de sólo 19,8%. El extracto hidrolizado ( H-100 Q) presentó leve actividad antiinflamatoria frente a AA, así como frente a TPA. El efecto antiinflamatorio fue de 25,0% y 35,7 % para AA y TPA, respectivamente. Sin embargo estos resultados no son estadísticamente significativos. Si bien la crema y el gel al 8% de ácido quillaico presentaron efecto antiinflamatorio éstos son menores que las del compuesto puro en ambos ensayos. En la evaluación de la actividad antiinflamatoria por vía oral, el ácido quillaico no presentó efecto antiinflamatorio. Las modificaciones estructurales realizadas al ácido quillaico disminuyeron el efecto antiinflamatorio. Partiendo de la esterificación del ácido quillaico, los resultados del efecto antiinflamatorio para el éster metil quillaico fueron de 27,3% y 38,4% para AA y TPA, respectivamente. Lo que demuestra que para ejercer el efecto es necesario el ácido carboxílico libre. Para la mayoría de los derivados, la actividad antiinflamatoria frente a TPA fue mayor que frente a AA. Nuestros estudios sugieren que la presencia del grupo aldehído podría ser importante para modular la actividad antiinflamatoria frente a AA, mientras que el grupo carboxilo puede modular la actividad antiinflamatoria frente a TPA. El extracto 100Q obtenido desde la corteza de Quillaja saponaria Mol. es una buena fuente de ácido quillaico, tritepenoide con excelente actividad antiinflamatoria tópica.