RESUMEN
Medicinal plants have been a traditional remedy for numerous ailments for centuries. However, their usage is limited due to a lack of evidence-based studies elucidating their mechanisms of action. In some countries, they are still considered the first treatment due to their low cost, accessibility, and minor adverse effects. Mexico is in second place, after China, in inventoried plants for medicinal use. It has around 4000 species of medicinal plants; however, pharmacological studies have only been carried out in 5% of its entirety. The species of the Mexican arid zones, particularly in semi-desert areas, exhibit outstanding characteristics, as their adverse growing conditions (e.g., low rainfall and high temperatures) prompt these plants to produce interesting metabolites with diverse biological activities. This review explores medicinal plants belonging to the arid and semi-arid zones of Mexico, focusing on those that have stood out for their bioactive potential, such as Jatropha dioica, Turnera diffusa, Larrea tridentata, Opuntia ficus-indica, Flourensia cernua, Fouquieria splendes, and Prosopis glandulosa. Their extraction conditions, bioactive compounds, mechanisms of action, and biological efficacy are presented, with emphasis on their role in the treatment of respiratory diseases. Additionally, current research, novel applications, and perspectives concerning medicinal plants from these zones are also discussed.
RESUMEN
The effectiveness of an alginate/chitosan nanomultilayer coating without (NM) and with Aloe vera liquid fraction (NM+Av) was evaluated on the postharvest quality of tomato fruit at 20 °C and 85% relative humidity (RH) to simulate direct consumption. Both nanomultilayer coatings had comparable effects on firmness and pH values. However, the NM+Av coating significantly reduced weight loss (4.5 ± 0.2%) and molds and yeasts (3.5-4.0 log CFU g-1) compared to uncoated fruit (16.2 ± 1.2% and 8.0 ± 0.0 log CFU g-1, respectively). It notably lowered O2 consumption by 70% and a 52% decrease in CO2 production, inhibiting ethylene synthesis. Visual evaluation confirmed NM+Av's efficacy in preserving the postharvest quality of tomato. The preservation of color, indicated by the Minolta color (a*/b*) values, demonstrated NM+Av's ability to keep the light red stage compared to uncoated fruit. The favorable effects of NM+Av coating on enhancing postharvest quality indicates it as a potential alternative for large-scale tomato fruit preservation.
RESUMEN
Plants from arid zones of Mexico are an interesting source of phytochemicals that exhibit a large number of biological properties. In this context, Rhus microphylla (Rm) and Myrtillocactus geometrizans (Mg) fruits have been used as folk remedies and to make traditional foods, respectively; however, studies on their composition and bioactivity are limited. Thus, the objective of this work was to evaluate the yields, phenolic composition, and bioactive properties (scavenging and reducing capacities, antiproliferative, and antifungal) of aqueous and hydroalcohol extracts of Rm and Mg fruits obtained by conventional agitation and ohmic heating (OH). The results showed that the Rm fruit extracts had the highest total phenolic content (TPC) values and the strongest scavenging and reducing capacities compared to those of Mg fruits, being characterized by the presence of gallic acid, while the composition of the Mg extracts varied with respect to the extraction conditions used. Regarding antifungal activity in vitro against two phytopathogenic fungi, Rhizopus stolonifer and Fusarium oxysporum, the hydroalcohol extracts obtained by conventional agitation of both plants (RmH-C and MgH-C) showed the best inhibitory effect, respectively. Interestingly, none of the extracts under study presented cytotoxicity against the noncancerous ARPE-19 cell line, while three extracts of Rm fruit exhibited a moderate antiproliferative activity against HeLa (cancerous) cell line. These findings reveal for the first time the potential of Rm and Mg fruits as a new source of bioactive compounds for future industrial applications.
