Abstract Pineapple slices were treated with three antioxidants and stored under passive modified atmosphere packaging (MAP) to evaluate the effect of these treatments on tissue browning (percentage of dark area) and the accumulation of ascorbic acid and total phenolics. Pineapple slices were immersed in ascorbic acid (AA), isoascorbic acid (IAA), and N-acetylcysteine (NAC) solutions for 2 min, and then were packed and stored at 5 °C under air (AIR) or MAP for 15 days. Water was used as control. The application of IAA and NAC under passive MAP reduced better the tissue browning index and maintained a good quality of the slices. The use of AA and IAA increased the contents of ascorbic acid and total phenolics. The application of IAA followed by storage under MAP conditions was effective in reducing tissue browning, which was associated with a higher retention of ascorbic acid and total phenolics contents of the pineapple slices.

The hymenolepiosis by Hymenolepis nana is a major public health problem in developing countries, and the commercial drugs against this parasitosis are not enough effective. The combination of antiparasitic and antioxidant agents has improved the treatment of some parasitoses. Thus, the development of new cestocidal and antioxidant agents to treat the hymenolepiosis cases is important. In the present study, four hydroxy- and four dihydroxy-chalcones were synthesized using the catalyst boron trifluoride diethyl etherate (BF3•OEt2). The antioxidant activity and antiparasitic against H. nana of chalcones were tested, as well as the toxicity by the brine shrimp lethality bioassay and the method of Lorke. The antioxidant activity was measured by three radical scavenging assays: 2,2’-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and ferric reducing antioxidant power (FRAP). The hydroxyl substitution pattern (number and position), mainly in ring B, was responsible for the chalcone antiparasitic activity. At least one meta or para hydroxyl group in ring B was essential for activity of the synthetic chalcones against H. nana; The time taken for the parasite to die by the 3b and 3e chalcones (20 mg/mL) treatment was up to six times lower than the control drug Praziquantel. On the other hand, chalcones with catechol structure in ring B (3g and 3h) showed the highest antioxidant values. The toxicity evaluations suggests that synthetic hydroxychalcones with cestocidal (3b and 3e) and antioxidant (3g and 3h) activities are safe compounds and potential in vivo agents to treat this parasitosis.

The agricultural drainage water from the Sinaloa valley (Mexico) is often reused in agriculture and aquaculture before reaching coastal water bodies. Discharged water must be of good quality to maintain the health of ecosystems and prevent damage to the organisms that compose them. This research determined the occurrence of coliforms in a drainage ditch known as La Michoacana (Sinaloa) that receives contaminated water from agricultural and urban sources. A section of 3.6 km was studied during 2013 and samples were obtained monthly from five equidistant sampling sites. Each water sample was analyzed for total coliform (TC) and fecal coliform (FC) content, pH, salinity, temperature, and dissolved oxygen percentage (%DO). The sampling sites with the highest bacterial contamination were associated with direct discharges of domestic wastewater and those with the lowest to the output drain. The performance of this agricultural ditch decreased the concentration of coliforms, with median and average values of 96% and 87% for TC, and 98% and 85% for FC, respectively. The most common bacteria were Escherichia coli (67.7%), Kluyvera cryocrescens (10.2%), and Enterobacter agglomerans (6.3%). Coliform concentration was positively correlated with temperature and negatively with %DO. The ditch improved the microbiological quality of the water, demonstrating remediation activities in the system. Proper management and maintenance of agricultural drainage ditches would favorably impact the health and biodiversity, as well as the intensive aquaculture and agricultural activities of the Sinaloa valley.

El agua que conducen los canales de drenaje del valle agrícola sinaloense (México) es reutilizada con frecuencia en la agricultura y acuacultura antes de ser depositada en las aguas costeras. La calidad del agua descargada debe ser adecuada para mantener la salud de los ecosistemas y evitar daño a los organismos que los componen. Esta investigación determinó la presencia de coliformes en el canal de drenaje agrícola conocido como La Michoacana (Sinaloa), que recibe agua contaminada de fuentes agrícolas y urbanas. Se estudió una sección de 3.6 km del canal durante el año 2013 y se recolectaron mensualmente muestras de agua de cinco puntos de muestreo equidistantes. A cada muestra se le analizó el contenido de coliformes totales (CT) y coliformes fecales (CF), pH, salinidad, temperatura y porcentaje de saturación de oxígeno disuelto (%OD). Los puntos de muestreo con mayor contaminación bacteriana estuvieron asociados a las descargas directas de agua residual doméstica, y aquellos con menor contaminación estuvieron asociados a la salida del canal de drenaje. El funcionamiento del canal disminuyó la carga de coliformes, con medianas y valores promedio del 96% y 87% para CT, y 98% y 85% para CF, respectivamente. Las principales bacterias identificadas fueron Escherichia coli (67.7%), Kluyvera cryocrescens (10.2%) y Enterobacter agglomerans (6.3%). La concentración de coliformes presentó una correlación positiva con la temperatura y negativa con el %OD. El canal de drenaje La Michoacana mejora la calidad microbiológica del agua que conduce, lo cual demuestra funciones de remediación en el sistema. El mantenimiento y manejo adecuado de los canales de drenaje agrícola puede impactar favorablemente la salud y biodiversidad, así como las actividades acuícolas y agrícolas intensivas del valle sinaloense.

Physicochemical characteristics of Ehretia tinifolia L. fruit are presented for the first time. The fruit of this plant is a small drupe of 8 mm diameter and weighs 0.2 g. Its pulp is slightly acidic (pH 5.8) with a high ratio of soluble solids (11 °Brix) to acidity (0.1%). The antioxidant activity of E. tinifolia fruits (DPPH, 303.8 mg EVC/100 g f.w.; ABTS, 84.1 mg EVC/100 g f.w.; DPPH, ABTS and EVC mean 1,1-diphenyl-2-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazolin-6-sulfonate) diammonium salt, and equivalents of vitamin C, respectively) was similar or higher than reported for several tropical fruits (e.g. orange, guava, and prickly pear). Ehretia tinifolia fruit has a high content of ash (12.6 mg/100 g d.w.). The edible portion is an important source of selenium (0.1 mg/100 g d.w.) and total fatty acids were 834.8 mg/100g d.w.; the main fatty acids were palmitic (27.6%), linoleic (26.4%), linolenic (18.1%), and oleic (17.6%). The content of fatty acids of seeds was 5 137.5 mg/100 g d.w., with linoleic (54.3%), oleic (22.9%), and palmitic (12.7%) as main components.

Se presentan por vez primera características fisicoquímicas del fruto de Ehretia tinifolia L. Este fruto es una drupa pequeña de 8 mm de diámetro y 0.2 g, su pulpa es ligeramente ácida (pH 5.8) y la relación de sólidos solubles (11 °Brix) a acidez (0.1%) es alta. La actividad antioxidante de los frutos de E. tinifolia (DPPH, 303.8 mg EVC/100 g p.f.; ABTS, 84.1 mg EVC/100 g p.f.; EVC significa equivalentes de vitamina C) fue similar o mayor que lo registrado para varios frutos tropicales (e.g. naranja, guayaba o tuna). El fruto presenta un alto contenido de cenizas (12.6 mg/100 g p.s.). La porción comestible es una fuente importante de selenio (0.1 mg/100 g p.s.) y el total de ácidos grasos fue de 834.8 mg/100g p.s.; los principales ácidos grasos fueron palmítico (27.6%), linoleico (26.4%), linolénico (18.1%) y oléico (17.6%). El contenido de ácidos grasos de las semillas fue 5 137.5 mg/100 g p.s.; siendo los principales componentes el linoleico (54.3%), oleico (22.9%) y palmítico (12.7%).

The objective of the present work was to determine the effect of Controlled Atmosphere (CA) storage on the postharvest quality and nutritional content of tomato (Solanum lycopersicum L.) 'Imperial'. Mature green fruit were stored at 12 °C under refrigeration (ambient air, AIR) or CA (4 kPa O2 + 96 kPa N2) at 12 °C for up to 21 days before being transferred to air at 23 °C for up to 12 days. Three fruits were taken per treatment after zero, four, eight and 12 days of ripening at 23 °C to evaluate external color, firmness, soluble solids content (SSC), CO2 and ethylene production rates, and ascorbic acid, β-carotene and lycopene content. CA storage delayed the loss of firmness and ascorbic acid degradation. It also decreased CO2 and ethylene production rate, β-carotene and lycopene synthesis, delaying red color development and ripening. The results indicate that storage of tomato fruit under CA extends the shelf life and the marketing period compared with traditional refrigeration systems.

El objetivo del presente trabajo fue determinar el efecto del almacenamiento en Atmósferas Controladas (AC) sobre la calidad poscosecha y el contenido nutricional de tomate (Solanum lycopersicum L.) 'Imperial'. Frutos de tomate en estado de madurez comercial fueron almacenados en refrigeración (aire ambiental, AIRE) o en AC (4 kPa O2 + 96 kPa N2) a 12 °C por 21 días antes de ser transferidos a un almacenamiento en aire a 23 °C por 12 días. Se retiraron tres frutas por cada tratamiento después de cero, cuatro, ocho y 12 días de maduración a 23 °C para evaluar el color externo, la firmeza, el contenido de sólidos solubles, las velocidades de producción de CO2 y etileno y el contenido de ácido ascórbico, β-caroteno y licopeno. El almacenamiento en AC disminuyó la pérdida de firmeza y la degradación de ácido ascórbico. También disminuyó la producción de CO2 y etileno y la síntesis de β-caroteno y licopeno; además, retrasó el desarrollo del color rojo y la maduración. Los resultados indican que el almacenamiento de tomate bajo condiciones de AC prolonga la vida de anaquel y el periodo de comercialización comparado con el sistema tradicional de refrigeración.