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.

In Zacatecas, the pitayas (Stenocereus spp) exist in several municipalities where they are collected for local consumption, although in recent years, in the municipality of Monte Escobedo, Zac., it has become a crop of high prospects for commercialization. Therefore, in this work an evaluation was made of four phenotypes of pitaya (according to the color of the mature fruit: yellow, white, purple and red). The fruits were harvested in commercial maturity. The following were evaluated in the plant: stem diameter, plant height, number of shoots per plant and number of fruits per shoot. In the fruit, the following were evaluated: fruit weight, pulp weight, peel weight, polar diameter, equatorial diameter, firmness, total sugars, reducing sugars, pH, titratable acidity and protein content in seeds and pulp. Yellow pitayas exhibited greater plant height with respect to the purple and a height equal to that of white and red. The yellow pitayas had a greater number of shoots per plant compared with the white and red. With respect to stem diameter, the yellow pitaya was smaller than other phenotypes. The purple pitayas presented a higher number of shoots with fruit than the white and red varieties. Due to the characteristics of fruit length, weight of rind, pulp and fruit, firmness, total soluble solids, titratable acids, protein content in pulp and seed, the red pitaya fruits are an option with potential for production and commercialization.

En Zacatecas las pitayas (Stenocereus spp) existen en varios municipios, donde son recolectadas para autoconsumo, aunque en años recientes, en el municipio de Monte Escobedo, Zac., se han convertido en un cultivo con altas perspectivas de comercialización. Por lo anterior, en este trabajo se evaluaron cuatro fenotipos de pitaya (según el color del fruto maduro: amarillo, blanco, morado y rojo). Los frutos se cosecharon en madurez comercial. En la planta se evaluó: diámetro del tallo, altura de planta, número de brotes por planta y número de frutos por brote. En el fruto se evaluó: peso de fruto, peso de pulpa, peso de cáscara, diámetro polar, diámetro ecuatorial, firmeza, azúcares totales, azúcares reductores, pH, acidez titulable y contenido de proteínas en semilla y pulpa. Las pitayas amarillas presentaron mayor altura de planta con respecto a la morada y una altura igual a las pitayas blanca y roja. Las amarillas tuvieron mayor número de brotes por planta que las pitayas blanca y roja. En relación al diámetro de tallo, la pitaya amarilla fue menor que otros fenotipos. Las moradas presentaron mayor número de brotes con fruto que las pitayas blanca y roja. Por las características de longitud del fruto, peso de cáscara, pulpa y fruto, firmeza, sólidos solubles totales, acidez titulable, contenido de proteína en pulpa y semilla, los frutos de pitaya roja son una opción con potencial para la producción y comercialización.