Abstract The aim of this work was to evaluate the nutrients and antioxidant compounds of three mixtures based on leaves of Portulaca oleracea L. (P), Amaranthus hybridus L. (A) and Chenopodium berlandieri L. (C). A mixtures design was made of which 10 combinations were obtained and three of the best mixtures were selected to analysis: OP1 (P+C), OP2 (P+A) and OP3 (C+A). A macronutrient, micronutrient analysis and a HPLC profile of phenolic compounds and amino acids were performed; in addition, in vitro antioxidant activity was measured by DPPH, ABTS and FRAP assays. Results showed that OP1 has a greater content of phenolic compounds, as evidenced by increases in antioxidant activity. Proximal chemical analysis showed that OP3 has a higher protein content and dietary fiber. The main phenolic compound present was phloridzin in OP1 and OP3; on the other hand, the amino acids lysine and glutamic acid were present at high concentrations in the three mixtures. These results showed that the OP1 mixture has the best antioxidant and nutritional properties; therefore, it has the potential to be included as an ingredient in food systems or nutraceutical and biomedical applications.

ABSTRACT Plant biodiversity provides a natural source of several compounds with biological activity, such as antioxidant and antifungal properties; such effects are related with the concentrations of phenols and flavonoids and different organs of the plants. In this research, aqueous (W) and 70% ethanol (Et70) extracts from flowers (F), leaves (L), stems (S) and roots (R) of Barkleyanthus salicifolius (Kunth) H. Rob. & Brettell were used to test antioxidant and antifungal activities and also the total concentration of phenols and flavonoids were analyzed; and types of phenolic acids and flavonoids were determined for each plant organ extract by HPLC. The Et70 enhance the extraction process of phenols and flavonoids, also showed higher antifungal and antioxidant activities. The obtained extract of the Et70 × F interaction showed the higher concentration of total phenols (57.90 mg GAE), flavonoids (91.03 mg QE) and antioxidant activity (285.07 Μm Trolox) per gram of dry extract. In addition, this extract shows an antifungal inhibition interval of 66.17% (Fusarium oxysporum) to 92.89% (Colletotrichum gloeosporioides). The phenol ferulic acid (35.57 mg g-1) and the flavonoid naringenina (206.60 mg g-1) were the compounds with the highest values founded in Et70-R, both of them compounds had been tested against fungal pathogens. Data indicate that antifungal and antioxidant activities are in function of phenolic acids and flavonoids concentration, as well as solvent used to extraction. Therefore, B. salicifolius species growing on wild form have the ability of accumulate several compounds with biological activity.

Abstract In order to evaluate the effect of three types of cooking (sautéed, boiled, and roasted) on content of the bioactive compounds, and antioxidant activity in tomato, four treatments were established: sautéed, boiled, roasted, and control (without application of some cooking method). Once the treatments were applied, the physiochemical properties such as total soluble solids (TSS), titratable acidity (TA), and pH were evaluated as well as the lycopene content, β-carotene, ascorbic acid, phenols and total flavonoids, and antioxidant activity in vitro by essays of 2-2diphenil-1-picrylhydrazil (DPPH), and 2,2'-azino-bis (3-ethylbenzothiazolino-6-sulfonic acid) (ABTS). All the cooking methods increased the TSS and reduced the acidity of the fruit. By roasting, a higher concentration of ascorbic acid (58.10%) was retained, as compared to the control. A significant increased (P ≤ 0.05) was observed in the concentration of carotenoids, and phenolic compounds in tomatoes due to the effect of the treatment sautéed, therefore a greater antioxidant activity. An inhibition of DPPH● radicals was found of 17.92%, and an antioxidant activity expressed as Trolox equivalents of 25.97 µM per g of fresh weight, as a result of the ABTS test. The boiling treatment caused a lixiviation effect of the bioactive compounds in the cooking media; therefore a smaller concentration was found. Sautéed was a better cooking method for tomatoes to obtain a higher concentration of antioxidant compounds.

Resumen Con el objetivo de evaluar el efecto de tres tipos de cocción (rehogado, hervido y asado), sobre el contenido de los compuestos bioactivos y la actividad antioxidante en tomate, se establecieron cuatro tratamientos: rehogado, hervido, asado y testigo (sin aplicación de algún método de cocción). Una vez aplicados los tratamientos fueron evaluadas las propiedades fisicoquímicas tales como sólidos solubles totales (SST), ácidez titulable (AT) y pH, así como el contenido de licopeno, β-caroteno, ácido ascórbico, fenoles y flavonoides totales y actividad antioxidante in vitro mediante los ensayos de 2-2-difenil-1-picrilhidrazilo (DPPH) y 2,2'-azino-bis (3-etilbenzotiazolino-6-ácido sulfónico) (ABTS). Todos los métodos de cocción aumentaron los SST y redujeron la acidez del fruto. Mediante el asado se retuvo una mayor concentración de ácido ascórbico (58.10%), respecto al testigo. Se observó un aumento significativo (P ≤ 0.05) en la concentración de carotenoides y compuestos fenólicos en tomates por efecto del rehogado y por lo tanto una mayor actividad antioxidante. Se encontró una inhibición del radical DPPH● de 17.92% y una actividad antioxidante expresada en equivalentes de Trolox de 25.97 µM por gramo de peso fresco, de acuerdo con el ensayo de ABTS. El hervido provocó un efecto de lixiviación de los compuestos bioactivos al medio de cocimiento y por lo tanto una menor concentración de estos compuestos. El rehogado fue el mejor método de cocción de tomates para obtener una mayor concentración de compuestos antioxidantes.

Abstract The aim of this work was to determine the antioxidant activity, total phenolic content (TPC) and total flavonoid content (TFC) in the rhizomes and stems of Jatropha dioica and their relation to collection season, collection location, extraction solvent and their interactions to understand the effect of climate conditions on the synthesis of the antioxidant compounds in J. dioica. Plants were collected during different seasons at two locations in Mexico. A 3-factorial experimental design was used for the stems and rhizomes, using the extraction solvent, collection location and season as sources of variation. A Tukey’s test with a P≤0.05 significance level was used to perform the comparison of the means. Significant differences were found when comparing the three sources of variation separately for TPC and antioxidant activity in the stems and rhizomes. In terms of the interactions for the stems, there was a significant difference between the Morelos × 70% ethanol × dry interaction and Tetepango × water × rain interaction for the TPC and the antioxidant activity; however, no significant difference was found for the TFC. In terms of the rhizomes, a significant difference was found among the 4 variables analyzed. These results indicate that collection location, collection season and extraction solvent affect the TPC and antioxidant activity. In addition, the rhizomes presented higher antioxidant activity and TPC than that of the stems.

Resumen El objetivo de este trabajo fue determinar la actividad antioxidante, el contenido de fenoles totales (TPC) y el contenido de flavonoides totales (TFC) en rizomas y tallos de Jatropha dioica, y su relación con la época de recolección, la localidad de la recolección, el solvente de extracción y sus interacciones, con el fin conocer el efecto de las condiciones climáticas sobre la síntesis de compuestos antioxidantes en J. dioica. Las plantas fueron recolectadas durante diferentes épocas en dos lugares de México. Se utilizó un diseño experimental 3 factorial en tallos y rizomas, usando como fuentes de variación el solvente de extracción, el lugar de recolección y la época de recolección. Se utilizó una prueba de Tukey con un P≤0.05 para realizar las comparaciones de medias. Se encontraron diferencias significativas cuando se compararon por separado las tres fuentes de variación para TPC y para la actividad antioxidante en tallos y rizomas. Respecto a las interacciones de los tallos, hubo una diferencia significativa entre la interacción Morelos × 70% de etanol × seco y la interacción Tetepango × agua × lluvia para TPC y para la actividad antioxidante; sin embargo, no se encontraron diferencias significativas para TFC. Respecto a los rizomas, se encontró una diferencia significativa entre las 4 variables analizadas. Esto indica que hay un efecto de la localidad de recolección, la época de recolección y el solvente de extracción sobre el TPC, y en la actividad antioxidante. Además, los rizomas presentaron una mayor actividad antioxidante y TPC que los tallos.