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Three experimental variables [methanol concentration, extraction time, and material-to-solvent ratio (w/v)] were optimized in the ultrasonic-assisted, Box-Behnken extraction of biocompounds (total phenols and flavonoids) from xoconostle ( Opuntia oligacantha) to determine the antibacterial activity against Salmonella typhimurium and Staphylococcus aureus. The total phenols and inhibitory effect on Staphylococcus aureus were optimal with 10 min of ultrasound and 40% methanol, and a ratio of 1:20 (w/v); the total flavonoids was optimal with 20 min of ultrasound, 40% methanol, and a 1:30 ratio (w/v); and the biocompound effect on Salmonella typhimurium was optimal with 10 min of ultrasound, 60% methanol and a ratio of 1:10 (w/v). The polynomial equations showed satisfactory accuracy in predicting the extraction yield. The total phenol content and Salmonella typhimurium and Staphylococcus aureus parameters were fit to a quadratic model, while for flavonoids, the fit was linear. The results showed that biocompounds extracted from xoconostle have a high inhibitory effect on Salmonella typhimurium and a moderate effect on Staphylococcus aureus. These xoconostle extracts can be used as a natural antibacterial additive in the food industry. Practical Application The use of natural antibacterial compounds in the food industry has been increasing. Xoconostle is the acidic fruit of the Nopal, or the cactus pear, which is endemic in the Americas. In this study, three variables of the ultrasound-assisted extraction of biocompounds from xoconostle were optimized for antibacterial activity using the surface-response Box-Behnken design, namely, the methanol concentration, extraction time, and material-to-solvent ratio (w/v). The results showed that the best conditions for the extraction of phenols and biocompounds with inhibitory activity against Staphylococcus aureus were the same, while the optimal conditions for the extraction of flavonoids and biocompounds with inhibitory activity against Salmonella typhimurium were different. The ultrasound-assisted xoconostle extractions of flavonoids, phenols, and biocompounds with antibacterial activity against pathogenic bacteria have potential applications as food additives. [ABSTRACT FROM AUTHOR]

Festuca arundinacea Schreb. is a widely used type of forage due to its great ecological breadth and adaptability. An agricultural intervention that improves the selenium content in cultivated plants has been defined as bio-fortification, a complementary strategy to improve human and non-human animals’ nutrition. The advancement of science has led to an increased number of studies based on nanotechnologies, such as the development of nanoparticles (NPs) and their application in crop plants. Studies show that NPs have different physicochemical properties compared to bulk materials. The objectives of this study were (1) to determine the behavior of F. arundinacea Schreb. plants cultivated with Se nanoparticles, (2) to identify the specific behavior of the agronomic and productive variables of the F. arundinacea Schreb. plants, and (3) to quantify the production and quality of the forage produced from the plant (the bioactive compounds’ concentrations, antioxidant activity, and the concentration of selenium). Three different treatments of SeNPs were established (0, 1.5, 3.0, and 4.5 mg/mL). The effects of a foliar fertilization with SeNPs on the morphological parameters such as the root size, plant height, and biomass production were recorded, as well as the effects on the physicochemical parameters such as the crude protein (CP), lipids (L), crude fiber (CF), neutral detergent fiber (NDF), acid detergent fiber (ADF), carbohydrates (CH), the content of total phenols, total flavonoids, tannins, quantification of selenium and antioxidant activity 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and 2,2-diphenyl-1-picrylhydrazyl (DPPH). Significant differences (p < 0.05) were found between treatments in all the response variables. The best results were obtained with foliar application treatments with 3.0 and 4.5 mg/mL with respect to the root size (12.79 and 15.59 cm) and plant height (26.18 and 29.34 cm). The F. arundinacea Schreb. plants fertilized with 4.5 mg/L had selenium contents of 0.3215, 0.3191, and 0.3218 mg/Kg MS; total phenols of 249.56, 280.02, and 274 mg EAG/100 g DM; and total flavonoids of 63.56, 64.96, and 61.16 mg QE/100 g DM. The foliar biofortified treatment with a concentration of 4.5 mg/mL Se NPs had the highest antioxidant capacities (284.26, 278.35, and 289.96 mg/AAE/100 g).

This article combines a Policy Analysis Matrix with a sensitivity and poverty line analysis with the objective of evaluating the economic contribution of comparative advantages to the private profitability and competitiveness of small-scale dairy systems. For 1 year, socioeconomic data were collected from 82 farms selected from four strata via statistical sampling. Two scenarios were established to determine the quantitative contribution of comparative advantages: (1) a simulated scenario, which accounted for the cost of purchasing the total food and the opportunity cost of the family labour force (FLF), and (2) an actual production scenario, which accounted for the cost of producing food and eliminating the payment of the FLF and included other income. The E3 and E4 producers were the most profitable and competitive in the simulated scenario and actual production scenario. Of the four scales evaluated, the E2 and E1 producers were the most efficient in taking advantage of the economic contribution provided by the comparative advantages in their own production of food and employment of the FLF, in addition to accounting for other income, a condition that increased their profitability by 171 and 144% and competitiveness by 346 and 273%, respectively. The poverty results indicated that only E3 and E4 producers were non-vulnerable in the simulated scenario and actual production scenario. The purchase of food was the comparative advantage with the greatest sensitivity to cost increases in the two scenarios analysed, which exacerbated the effect on the E1 and E2 producers.