The Myrtillocactus geometrizans (Mart. ex. Pfeiff.) fruit, locally called garambullo, is an important source of bioactive compounds, mainly betalains, polyphenols, and ascorbic acid. However, information on the application of post-harvest technologies that prolong the shelf life of the fruits is still insufficient. The objective of the present research was to evaluate the effect of a gelatin coating incorporating 0%, 1%, or 3% tomato oily extract (TOE), compared to a control (without coating), on the physicochemical and antioxidant properties of garambullo fruits stored for 15 days at 5 °C. The gelatin coatings with TOE significantly (p ≤ 0.05) delayed changes in weight loss, brix degrees, titratable acidity and pH, compared to the control during storage. Fruits coated with TOE-gelatin had a higher content of betalains, ascorbic acid, total phenols, and flavonoids. The results showed that a higher concentration of phytochemicals increased antioxidant activity in vitro; the maximum values found for Trolox equivalents per kg of fresh weight were 10.46 and 17.65 mM for the 2,2′-diphenyl-1-picrylhydrazyl (DPPH) and Trolox Equivalent Antioxidant Capacity Method (TEAC) tests, respectively. The gelatin coating with TOE-3% (COTE-3%) reduced water loss by 1.66 times, compared to the control. In addition, the fruits covered with COTE-3% showed the highest concentration of bioactive compounds during storage.

The aim of this work was to evaluate the effects of oily tomato extract (OTE) at concentrations of 0, 1, 3 and 5% on the physicochemical and antioxidant properties of gelatin-based films. Characterization of the extract showed lycopene and β-carotene concentrations of 159.15 and 20.38 μg/mL, respectively. The results showed that the addition of OTE was associated with a decrease in moisture content, a lower solubility, a lower water vapor permeability, and a lower Young’s modulus, while the elongation percentage showed a significant increase. The addition of OTE improved the barrier properties of the films against UV and visible light. The higher the OTE concentration was, the greater the amounts of lycopene and β-carotene within the films, and therefore, the higher the antioxidant activity was (2.49 μM Trolox equivalents per g of film). The results suggest that the addition of OTE to gelatin-based films can improve their mechanical properties and increase their antioxidant capacity.

Moringa oleifera Lam is a plant that has recently gained importance as a food because of its nutritional value and bioactive compound content and because practically all the organs are usable. The use of nanoparticles has appeared as an alternative to increase bioactive compounds in plants. The goal of this work was to determine if the application of copper nanoparticles would increase the content of bioactive compounds and antioxidant capacity in M. oleifera. Copper (Cu) nanoparticles were applied to the leaves at four different times throughout crop growth. The biocompounds were analyzed after the second, third, and fourth applications. The results show that application of Cu nanoparticles has a beneficial effect on the accumulation of bioactive compounds in M. oleifera leaves. In addition, the antioxidant capacity and carotenoid and chlorophyll contents in the leaves of M. oleifera increased after Cu nanoparticles application. The same effect was not observed in the fruit of M. oleifera. Here, the bioactive compound contents diminished. Therefore, the use of Cu nanoparticles can be an important alternative to improve the quality of this plant, particularly that of the leaves.

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.

In this study, we evaluated the effects of edaphic fertilization with N, P, and K (150-50-80, 100-60-60, and without edaphic fertilization (SFE)) and foliar fertilization with nanoparticles (NPs) of Se and Zn (Se: 50 ppm, Zn: 250 ppm, and no nanoparticles (NP0)) on the yield and antioxidant compounds of apple fruits. We conducted this study in a 20-year-old commercial orchard. The experimental design was a randomized complete block design of nine treatments. The treatments with fertilization doses of 150-50-80 and 100-60-60, supplemented with Se and Zn NPs, generally increased the yield, sugar content, and ascorbic acid of the apple fruits. The SFE + NPZn treatment produced the highest increase (+193% compared with the control) in fruit yield. The SFE + NPSe and SFE + NPZn treatments led to higher contents of phenols and flavonoids, with maximum values of 7.6 mg GAE and 15.82 mg QE per gram of dry weight. These compounds presented a direct correlation with the antioxidant activity in the fruits. The foliar application of Se and Zn nanoparticles supplemented the soil fertilization with N, P, and K to improve the yield and bioactive-compound synthesis of the apple fruits.