Antiproliferative Effect of Essential Oil Obtained from Oregano (Lippia palmeri S. Watson) Leaves Grown in Hydroponics and LED Light.

Nowadays, light-emitting diodes (LED) provide an alternative source to sunlight with specific intensity and wavelength that promotes plant growth. The features offered by LED could also stimulate the production of secondary metabolites of pharmaceutical interest. This work analyzed the cultivation of oregano (Lippia palmeri S. Watson) in a floating root hydroponic system supplemented by full-spectrum LED artificial light. Growth indicators like height, diameter, number of shoots, and leaf length and width were measured. The essential oil (EO) composition from the leaves of wild and hydroponic conditions found thymol (41.8 %) as the main product for the former and carvacrol (47 %) in hydroponics. The antiproliferative activity of EOs on human colorectal cancer HCT-15 shows that 6.4 µg/ml for hydroponic and 7.4 µg/ml for the wild plant reduce more than 50 % the cell viability. Overall, this study indicates that hydroponic conditions and full spectrum LED modifies the composition of the EO of L. palmeri on compared with the wild plant, which effectively induces cell growth inhibition in human colorectal cancer.

Treatment with Argovit® Silver Nanoparticles Induces Differentiated Postharvest Biosynthesis of Compounds with Pharmaceutical Interest in Carrot (Daucus carota L.).

The global market for plant-derived bioactive compounds is growing significantly. The use of plant secondary metabolites has been reported to be used for the prevention of chronic diseases. Silver nanoparticles were used to analyze the content of enhancement phenolic compounds in carrots. Carrot samples were immersed in different concentrations (0, 5, 10, 20, or 40 mg/L) of each of five types of silver nanoparticles (AgNPs) for 3 min. Spectrophotometric methods measured the total phenolic compounds and the antioxidant capacity. The individual phenolic compounds were quantified by High Performance Liquid Chromatography (HPLC) and identified by -mass spectrometry (HPLC-MS). The five types of AgNPs could significantly increase the antioxidant capacity of carrots' tissue in a dose-dependent manner. An amount of 20 mg/L of type 2 and 5 silver nanoparticle formulations increased the antioxidant capacity 3.3-fold and 4.1-fold, respectively. The phenolic compounds that significantly increased their content after the AgNP treatment were chlorogenic acid, 3-O-caffeoylquinic acid, and 5'-caffeoylquinic acid. The increment of each compound depended on the dose and the type of the used AgNPs. The exogenous application of Argovit® AgNPs works like controlled abiotic stress and produces high-value secondary bioactive compounds in carrot.

Green synthesis of silver nanoparticles using Lysiloma acapulcensis exhibit high-antimicrobial activity.

The scientific community is exploiting the use of silver nanoparticles (AgNPs) in nanomedicine and other AgNPs combination like with biomaterials to reduce microbial contamination. In the field of nanomedicine and biomaterials, AgNPs are used as an antimicrobial agent. One of the most effective approaches for the production of AgNPs is green synthesis. Lysiloma acapulcensis (L. acapulcensis) is a perennial tree used in traditional medicine in Mexico. This tree contains abundant antimicrobial compounds. In the context of antimicrobial activity, the use of L. acapulcensis extracts can reduce silver to AgNPs and enhance its antimicrobial activity. In this work, we demonstrate such antimicrobial activity effect employing green synthesized AgNPs with L. acapulcensis. The FTIR and LC-MS results showed the presence of chemical groups that could act as either (i) reducing agents stabilizing the AgNPs or (ii) antimicrobial capping agents enhancing antimicrobial properties of AgNPs. The synthesized AgNPs with L. acapulcensis were crystalline with a spherical and quasi-spherical shape with diameters from 1.2 to 62 nm with an average size diameter of 5 nm. The disk diffusion method shows the magnitude of the susceptibility over four pathogenic microorganisms of clinical interest. The antimicrobial potency obtained was as follows: E. coli ≥ S. aureus ≥ P. aeruginosa > C. albicans. The results showed that green synthesized (biogenic) AgNPs possess higher antimicrobial potency than chemically produced AgNPs. The obtained results confirm a more significant antimicrobial effect of the biogenic AgNPs maintaining low-cytotoxicity than the AgNPs produced chemically.