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The use of silver nanoparticles (AgNPs) is increasing nowadays due to their applications against phytopathogens. Temporary Immersion Systems (TIS) allow the micropropagation of plants in liquid media. This work aims to develop an effective protocol for apricot micropropagation in TIS and to study the necessary conditions to introduce AgNPs in apricot plants, as well as the effect of its application on proliferation-related parameters. AgNPs were introduced in different media at a concentration of 100 mg L−1 to test the incorporation of silver to plant tissues. Silver content analysis was made by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). The effect of initial shoot density and the addition of AgNPs on micropropagation were evaluated after four weeks in culture on TIS. Productivity, proliferation, shoot-length and leave surface were measured. The better micropropagation rate was obtained with 40 initial shoots, 2 min of immersion every 6 h and 3 min of aeration every 3 h. To introduce AgNPs in apricot plants it is necessary to culture them in liquid media without chloride in its composition. These results will contribute to the development of an in vitro protocol for virus inhibition by AgNPs application. This depends on the introduction of Ag nanoparticles within the plant tissues, and this is not possible if AgNPs after interaction with Cl- ions precipitate as silver chloride salts.

The purpose of this work was to determine the secondary metabolites generated by O. basilicum cell suspensions, as well as their insecticide and inhibitory activity against R. ferrugineus. The growth kinetics with inoculation Verticillium dahliae were determined and identified using LC-MS. Determination of total phenolic components (TFC), flavonoids (TF), and condensed tannins (TCT) were measured. Insecticidal activity of O. basilicum extract against R. ferrugineus (larva and adult) and proteolytic enzymes activity were assessed (in vitro and in vivo). The O.basilicum extract had an LC50 of 1238 µg/mL and an LD50 of 13.4 µg/larva. The LC50 of chicoric acid, ursolic acid, salvigenin, quercetin-3-O-rutinoside, rosmarinyl glucoside, and nepetoidin B demonstrated activity at an LC50 of 1132, 1167, 1189, 1214, 1275, and 1317 µg/mL, respectively. Chicoric acid, salvigenin, nepetoidin B, and rosmarinic acid demonstrated an LD50 activity of 10.23, 11.4, 11.9, and 12.4 µg/larva, respectively. The active extract of O. basilicum inhibited total protease, trypsin-like serine proteinases, elastase, cysteine, and metalloprotease activity with an IC50 (in vitro) of 119.4, 91, 102.4, 76.4, and 52.4 µg/mL, respectively. In silico studies of compounds were conducted, such as molecular docking and ADMET analysis. The study proposes using an efficient cell suspension technique to produce O. basilicum extract containing active secondary metabolites and accessible using as bio-insecticide.

Cantilever resonators based on the roof tile-shaped modes have recently demonstrated their suitability for liquid media monitoring applications. The early studies have shown that certain combinations of dimensions and order of the mode can maximize the Q-factor, what might suggest a competition between two mechanisms of losses with different geometrical dependence. To provide more insight, a comprehensive study of the Q-factor and the resonant frequency of these modes in microcantilever resonators with lengths and widths between 250 and 3000 µm and thicknesses between 10 and 60 µm is presented. These modes can be efficiently excited by a thin piezoelectric AlN film and a properly designed top electrode layout. The electrical and optical characterization of the resonators are performed in liquid media and then their performance is evaluated in terms of quality factor and resonant frequency. A quality factor as high as 140 was measured in isopropanol for a 1000 × 900 × 10 µm3 cantilever oscillating in the 11th order roof tile-shaped mode at 4 MHz; density and viscosity resolutions of 10−6 g/mL and 10−4 mPa·s, respectively are estimated for a geometrically optimized cantilever resonating below 1 MHz.

A study was conducted to determine the effect of dielectric barrier discharge non-thermal plasma (DBD-NTP) on Salmonella typhimurium and Staphylococcus aureus populations on solid surfaces and in liquid suspensions. Our results showed that inactivation kinetics of S. typhimurium and S. aureus by DBD-NTP treatments can be well predicted with mathematical models. The survival curves of both S. typhimurium and S. aureus showed a log-linear phase followed by tailing behaviors on solid surfaces, and shoulder behaviors followed by a log-linear phase in liquid suspensions. The D values (decimal reduction time) for S. typhimurium and S. aureus in suspension were higher than those on solid surfaces (p < 0.05). Additionally, the maxima of sublethal injury values under low NaCl concentration and neutral pH condition were higher than those under high NaCl and low pH condition. In addition, mathematical modeling was evaluated to predict the final inactivation result for potential industrial applications. This study indicates that different microbial supporting matrices significantly influence the inactivation effect of DBD-NTP; it also provides useful information for future applications of NTP in enhancing food shelf life and safety.

The purpose of this work was to determine the secondary metabolites generated by O. basilicum cell suspensions, as well as their insecticide and inhibitory activity against R. ferrugineus . The growth kinetics with inoculation Verticillium dahliae were determined and identified using LC-MS. Determination of total phenolic components (TFC), flavonoids (TF), and condensed tannins (TCT) were measured. Insecticidal activity of O. basilicum extract against R. ferrugineus (larva and adult) and proteolytic enzymes activity were assessed (in vitro and in vivo). The O. basilicum extract had an LC 50 of 1238 µg/mL and an LD 50 of 13.4 µg/larva. The LC 50 of chicoric acid, ursolic acid, salvigenin, quercetin-3-O-rutinoside, rosmarinyl glucoside, and nepetoidin B demonstrated activity at an LC 50 of 1132, 1167, 1189, 1214, 1275, and 1317 µg/mL, respectively. Chicoric acid, salvigenin, nepetoidin B, and rosmarinic acid demonstrated an LD 50 activity of 10.23, 11.4, 11.9, and 12.4 µg/larva, respectively. The active extract of O. basilicum inhibited total protease, trypsin-like serine proteinases, elastase, cysteine, and metalloprotease activity with an IC 50 (in vitro) of 119.4, 91, 102.4, 76.4, and 52.4 µg/mL, respectively. In silico studies of compounds were conducted, such as molecular docking and ADMET analysis. The study proposes using an efficient cell suspension technique to produce O. basilicum extract containing active secondary metabolites and accessible using as bio-insecticide.