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The native Chilean shrubs Buddleja globosa (Matico) and Ribes magellanicum (Zarzaparrilla) are used widely at a rural level, due to their medicinal properties. Nevertheless, little is known about their secondary metabolites and cytotoxic effect. The aim of this study was to evaluate the content of different compounds like catechin, epicatechin, p-coumaric acid and the antioxidant capacity by ABTS, ORAC, FRAP and DPPH methods. In addition, the cytotoxic activity of both extracts was evaluated against Chinese hamster ovary (CHO-K1) cell lines by MTT and neutral red assays. The results suggest that the most abundant constituent in Budleja globosa and Ribes magellanicum were catechin (682.43 mg/100 g DW) and epicatechin (3362.08 mg/100 g DW) respectively; while the ORAC methodology showed an elevated antioxidant activity for Matico (134147.31 μmol Trolox Eq/100 g DW). On the other hand, both extracts at the assayed concentrations affect the membrane stability and cellular metabolic capacity of the CHO-K1 cell lines. These finding provide a direction for further researches, and suggest the Matico and Zarzaparrilla flower extracts as promising sources of antioxidants, and as research objects through the analyze of their metabolic behavior and antitumoral potential.

Six native plants of South America traditionally consumed in the Patagonian region (southern Argentina and Chile), namely: Adesmia boronioides Hook. f., Apium australe Thouars, Buddleja globosa Hope, Drimys andina (Reiche) R. Rodr. & Quezada, Dysphania multifida L. and Solidago chilensis Meyen were investigated to determine the nutraceutical properties of infusions of their aerial parts. The infusions were characterized in terms of their antioxidant activity, phenolic and flavonoid content, profile of phenolic compounds, general toxicity and cytotoxicity on two different human cell lines: T84 (derived from colon cancer) and HTR8/SVneo (not derived from cancer). Twenty-nine compounds, mainly phenolic acids and flavonoids, were identified. This is the first analysis of phenolic compounds in infusions from native plants of Patagonia. D. andina, B. globosa and S. chilensis showed high levels of antioxidants, even higher than those of Green Tea. The content of phenolic compounds correlated significantly with the antioxidant activity of the samples analyzed. The toxicity test indicated that the use of A. australe, B. globosa and D. multifida seems safe, but a moderate consumption is suggested for A. boronioides, D. andina and S. chilensis until more exhaustive and long-term results are available. Moreover, A. boronioides and S. chilensis showed anticancer potential due to their antiproliferative activity on human cancer cell lines. Fil: Gastaldi, Bruno. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel; Argentina Fil: Marino, Gabriela Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina Fil: Assef, Yanina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Silva Sofrás, Fresia Melina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina Fil: Catalan, Cesar Atilio Nazareno. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: González, Silvia Beatriz. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel; Argentina

The antioxidant and antihemolytic properties contained in the leaves of Buddleja globosa (B. globosa), also known as "Matico," were determined. Aqueous extracts of leaves were assayed in human erythrocytes and molecular models of its membrane. The latter were bilayers built-up of lipids located in the outer and inner leaflets of the erythrocyte membrane. Observations by scanning electron microscopy showed that the extract altered the morphology of erythrocytes inducing the formation of crenated echinocytes. This result implied that the extract components were inserted into the outer leaflet of the cell membrane. This conclusion was confirmed by experiments carried out by fluorescence spectroscopy of red cell membranes and vesicles (LUV) of dimyristoylphosphatidylcholine (DMPC) and by X-ray diffraction of DMPC and dimyristoylphosphatidylethanolamine bilayers. Human erythrocytes were in vitro exposed to HClO, which is a natural powerful oxidant. Results demonstrated that low concentrations of B. globosa aqueous extract neutralized the harmful capacity of HClO. Hemolysis experiments also showed that the extract in very low concentrations reduced hemolysis induced by HClO.

In vitro tests are now widely employed in ethnopharmacological research because of ethical reasons and their usefulness in bioactive-guided fractionation and determination of active compounds. For many disease conditions, a variety of in vitro tests can now be employed as the biochemical mechanisms underlying disease and healing processes are understood. Approaches to the in vitro investigations of wound healing processes are exemplified by studies on extracts of Buddleja species and three Ghanaian species Spathodea campanulata, Commelina diffusa and Secamone afzelii. Most studies have been carried out on Buddleja officinalis or Buddleja globosa. The extracts have been shown to have anti-inflammatory and antioxidant properties due to flavonoids, triterpenoids, diterpenoids and caffeic acid derivatives. There appears to a slight effect on proliferation of fibroblasts at lower concentrations, but this was not significant, and higher concentrations appeared to be cytotoxic. Novel findings are the ability of Buddleja globosa leaf extracts to induce differentiation in keratinocytes and to alter the profile of proteins produced by cultured fibroblasts. Extracts also had some effect on lattice contraction. The three Ghanaian species examined show a mixture of antimicrobial and antioxidant activities. The evolution over recent years of tests for wound healing, from in vivo tests to cell-based systems and chemical reactions and on to investigations into effects on secondary messengers and protein expression, is described.

An aqueous extract of Buddleja globosa leaves, used traditionally in Chile for wound healing, was tested for the ability to stimulate growth of fibroblasts in vitro and for antioxidant activity in the same fibroblast cell system challenged with hydrogen peroxide. Low concentrations of the extract gave an increase in fibroblast growth which was not statistically significant but cytotoxicity was observed at concentrations greater than 50 microg/ml. The extract showed strong antioxidant effect and fractionation led to the isolation of three flavonoids and two caffeic acid derivatives, each of which was shown to contribute to the antioxidant effect at concentrations below 10 microg/ml. These activities would accelerate the healing of wounds.

Numerous investigations exist about the alterations that oxygen free radicals can provoke on biomolecules; these modifications can be prevented and/or reversed by different antioxidants agents. On the other hand, 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), a stable nitrogen synthetic radical, is used to evaluate the antioxidant capacity of medicinal herbal products; however, the structural changes that this radical provoke on the herbal active principles are not clear yet. In this work, we compared the redox reactivity of oxygen free radicals and DPPH radical on phospholipids and protein thiol groups present in rat liver microsomes. Cu2+/ascorbate was used as generator system of oxygen free radical and as antioxidant, an extract of Buddleja globosa's leaves. Cu2+/ascorbate provoked microsomal lipid peroxidation, microsomal thiols oxidation and oxygen consumption; all of these phenomena were inhibited by B. globosa extract. On the other hand, DPPH was bleached in different extension by the herbal extract and phosphatidyl choline; beside, DPPH decreased microsomal thiols content, but this phenomenon were not prevented by the herbal extract. Furthermore, DPPH did not induce oxygen consumption and neither modified the oxygen consumption induced by Cu2+/ascorbate. Distinct redox mechanisms may explain the differences between the reactivity of DPPH and oxygen free radicals on biomolecules, which is discussed.