The Impact of 2-Ketones Released from Solid Lipid Nanoparticles on Growth Modulation and Antioxidant System of Lactuca sativa

Abstract

2-Ketones are signal molecules reported as plant growth stimulators, but their applications in vegetables have yet to be achieved. Solid lipid nanoparticles (SLNs) emerge as a relevant nanocarrier to develop formulations for the controlled release of 2-ketones. In this sense, seedlings of Lactuca sativa exposed to 125, 375, and 500 µL L−1 of encapsulated 2-nonanone and 2-tridecanone into SLNs were evaluated under controlled conditions. SLNs evidenced a spherical shape with a size of 230 nm. A controlled release of encapsulated doses of 2-nonanone and 2-tridecanone was observed, where a greater release was observed as the encapsulated dose of the compound increased. Root development was strongly stimulated mainly by 2-tridecanone and leaf area (25–32%) by 2-nonanone. Chlorophyll content increased by 15.8% with exposure to 500 µL L−1 of 2-nonanone, and carotenoid concentration was maintained with 2-nonanone. Antioxidant capacity decreased (13–62.7%) in L. sativa treated with 2-ketones, but the total phenol concentration strongly increased in seedlings exposed to some doses of 2-ketones. 2-Tridecanone strongly modulates the enzymatic activities associated with the scavenging of H2O2 at intra- and extracellular levels. In conclusion, 2-ketones released from SLNs modulated the growth and the antioxidant system of L. sativa, depending on the dose released.

The Biosynthesis, Accumulation of Phenolic Compounds and Antioxidant Response in Lactuca sativa L. Plants Inoculated with a Biofertilizer Based on Soil Yeast and Iron Nanoparticles

“…The isomer of chicoric acid was the compound quantified with higher concentrations, mainly in treatments T1 and T2, both treatments inoculated with the yeast C. guillermondii; moreover, the results reported here are higher than those obtained by Santander et al (2020) [21] using lettuce belonging to cultivar Lollo Bionda and inoculated with Claroideoglomus claroideum, reaching concentrations of 120 µg g −1 , and higher than those reported by [50], which showed concentrations of 2-9 µg g −1 of chicoric acid in lettuce plants supplied with lipid nanoparticles as a carrier for two ketones. In addition, Gonzalez et al (2023) [51] inoculated lettuce plants with Actinobacteria spp.…”

“…Flavonols also presented high concentrations, specifically quercetin-3-glucoronide, in the treatments inoculated with C. guillermondii and with R. mucilaginosa, also showing concentrations higher than those reported by Santander et al (2020 and [10,21] in different lettuce cultivars inoculated with two different arbuscular mycorrhizal fungi and subjected to salt stress (12 and 20 µg g −1 ). This could be explained because the production of phenolic compounds is modulated by factors such as plant genotype, the presence of PGPM, and biotic or abiotic stress factors, including the presence of metallic nanoparticles [10,[50][51][52].…”

“…Different procedures to report antioxidant capacities are commonly used to evaluate the response of the plant defence system [54]. Specifically, the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), Trolox equivalent antioxidant activity (TEAC) and cupric ion reducing antioxidant activity (CUPRAC) were evaluated in leaves and roots to provide a complete visual regarding the elimination of free radicals [50]. The oxygen radical absorbance capacity (ORAC) was evaluated only in leaves.…”