Agronomic Behavior of Mexican Roselle Cultivars Produced under Protected Agricultural Conditions.

Growth dynamics and morphological traits are used to define the characteristics of roselle cultivars Hibiscus sabdariffa. The morpho-agronomic variability of plants was evaluated, as well as the concentration of macro and micronutrients in leaves of Mexican roselle cultivars in hydroponic and greenhouse conditions. The following roselle cultivars were studied: 'Cruza Negra', 'UAN16-2', 'Criolla Huajicori', 'UAN 6 Puga', 'UAN 25-1' and '4Q4'. The relative growth rate of the crops was fitted to a positive cubic, negative quadratic and positive linear model, whereas stem diameter, fitted to a linear model, had a negative quadratic response. The foliar surface of the cultivars '4Q4', 'Cruza Negra', 'UAN16-2' and 'Criolla Huajicori' was directly related to the size of the flower, the calyx and the corolla. Nitrogen and potassium are the elements that showed the highest concentration in the cultivars Criolla Huajicori and Cruza Negra, while in the other four cultivars the highest concentrations of minerals in the leaf were nitrogen and calcium. The leaves of cultivar 4Q4 provided the greatest amount of minerals, with 83,565 mg kg-1 dry basis. Criolla Huajicori was the cultivar that exhibited the tallest height, the most productive branches and the greatest calyx number per plant; however, Cruza Negra exhibited the highest yield by having the longest calyx.

Vegetable oils as green solvents for carotenoid extraction from pumpkin (Cucurbita argyrosperma Huber) byproducts: Optimization of extraction parameters.

Pumpkin pulp is the main waste generated by pumpkin seed growers. This agro-industrial waste is a valuable source of bioactive compounds, especially carotenoids (ß-carotene, α-carotene, and lutein), which exhibit a broad spectrum of health-promoting effects. In this study, vegetable oils (canola, corn, and soybean oil) were used as green solvent alternatives to conventional organic solvents for carotenoid extraction from dried pumpkin pulp (DPP) waste. The highest carotenoid extraction yield (CEY) was obtained with canola oil, at a 1:10 DPP/oil ratio. Response surface methodology (RSM) was used to optimize the extraction process parameters (temperature, time, and stirring rate) through a Box-Behnken design (BBD) maximizing CEY in canola oil. The extraction temperature and stirring rate were found to have a significant linear and quadratic effect, respectively, on CEY. Optimum conditions were achieved at 21.8 min, 250 rpm, and 60°C. Under these optimized conditions, the estimated value for CEY was 378.1 µg ß-carotene equivalents/g of DPP, corresponding to 61.6% of the total carotenoid content present in the DPP. In contrast, the observed experimental value was 373.2 µg ß-carotene equivalents/g of DPP (61.2%). The experimental value was very close to the estimated value, which verifies the model's adequacy and fit. This study shows an alternative method to extract carotenoids from DPP with canola oil, obtaining an oil naturally enriched with carotenoids that could be used as a potential functional ingredient in the development of food, cosmetics, and medicinal products. PRACTICAL APPLICATION: Pumpkin by-products are a potential carotenoid source. Vegetable oil can be used as an alternative solvent for carotenoid extraction from pumpkin residues to obtain an enriched carotenoid oil that can be used to formulate food products.

Anthocyanin Induction by Drought Stress in the Calyx of Roselle Cultivars.

Abiotic factors can alter the chemical profile of crops and the number of compounds they contain. In this study, the anthocyanin and anthocyanidin contents, determined by ultra-performance liquid chromatography (UPLC-MS/MS), and the colour attributes of the calyces of three cultivars of Hibiscus sabdariffa subjected to three water stress regimes during the stage of physiological maturity were investigated. The total anthocyanin content in calyx increased relative to the control content under a 65% moisture irrigation regime. Among the cultivars, UAN16-2 showed the greatest increases in the contents of cyanidin, delphinidin 3-O-glucoside, cyanidin 3-O-glucoside, and cyanidin 3-O-sambubioside. The content of cyanidin 3-O-sambubioside showed the greatest increase, increasing by 55% relative to the control level. The contents of these compounds are correlated with colour attributes such as luminosity. Water stress under the 33% moisture condition during plant development led to decreased anthocyanin contents in all of the roselle cultivars.

Cadmium, copper, lead, and zinc contents of fish marketed in NW Mexico.

To assess if they were within the safety limits for human consumption, the Cd, Cu, Pb, and Zn contents of fish muscles, bought from separate stalls of the fish markets of nine cities of NW Mexico, were determined by atomic absorption spectrophotometry. Considering all fish and markets, the mean contents were Zn: 23.23 ± 5.83, Cu: 1.72 ± 0.63, Cd: 0.27 ± 0.07, and Pb: 0.09 ± 0.04 µg/g (dry weight). Cu, Zn, and Pb did not reach levels of concern for human consumption, but the high Cd values determined in Mazatlán (Mugil cephalus: 0.48 ± 0.15; Diapterus spp.: 0.57 ± 0.33; Lutjanus spp.: 0.72 ± 0.12; small shark: 0.87 ± 0.19 µg/g dry weight) indicate that this was the only metal of concern for human health because the daily individual consumption of fish muscle to reach the PTDI would be within 0.27 and 0.41 kg.

Cadmium, copper, lead, and zinc in Mugil cephalus from seven coastal lagoons of NW Mexico.

The increasing order of the mean concentrations of Cd, Cu, and Zn in the tissues of Mugil cephalus of seven coastal lagoons of Sinaloa State (NW Mexico) was liver > gills > muscle, while for Pb it was gills > muscle ≥ liver. There were no differences between the mean concentrations of Cd and Pb of the three tissues determined in the samples of the seven lagoons and, although there were some significant differences, there was no indication of a latitude-related trend in the distribution of Cu and Zn: the Cu content of the muscle tended to be higher in the northern than in the southern lagoons, although in the case of the gills the highest and lowest mean values indicated an opposite trend, with the highest and lowest values in one southern and one northern lagoon. In the case of the liver, there were no differences and no indication of a regional trend. There were no differences in the mean Zn contents of muscle and gills; in the case of the liver, one of the lagoons of the central part of the state had a significantly higher value than one of the southern lagoons and all the rest had similar values. In addition, there was no clear indication of season-related differences in any of the three tissues. According to our results, the metal contents of the muscle of this species are not of concern for human health, since the allowable ingestion would be in the order of 0.9 kg/day.

The metal content of bivalve molluscs of a coastal lagoon of NW Mexico.

The lagoonal system Altata-Ensenada del Pabellón supports important traditional fisheries and mollusc cultures and receives urban and agricultural effluents. The annual mean Cd contents of the oyster and mussel Crassostrea gigas and Mytella strigata of the inner mangrove swamps were higher than that of the clam Megapitaria squalida, which lives in areas under marine influence. Crassostrea corteziensis had the highest Cu and Zn contents, showing that it is a strong accumulator of both metals and especially of Zn, and there were no significant differences in the Pb content of the three species.