In recent years, the interest in cannabidiol (CBD) has increased because of the lack of psychoactive properties. However, CBD has low solubility and bioavailability, variable pharmacokinetics profiles, poor stability, and a pronounced presystemic metabolism. CBD nanoformulations include nanosuspensions, polymeric micelles and nanoparticles, hybrid nanoparticles jelled in cross-linked chitosan, and numerous nanosized lipid formulations, including nanostructured lipid carriers, vesicles, SNEEDS, nanoemulsions, and microemulsions. Nanoformulations have resulted in high CBD solubility, encapsulation efficiency, and stability, and sustained CBD release. Some studies assessed the increased C_max and AUC and decreased T_max. A rational evaluation of the studies reported in this review evidences how some of them are very preliminary and should be completed before performing clinical trials. Almost all the developed nanoparticles have simple architectures, are well-known and safe nanocarriers, or are even simple nanosuspensions. In addition, the conventional routes of administration are generally investigated. As a consequence, many of these studies are almost ready for forthcoming clinical translations. Some of the developed nanosystems are very promising for a plethora of therapeutic opportunities because of the versatility in terms of the release, the crossing of physiological barriers, and the number of possible routes of administration.

Essential oils (EOs) are reported to be natural pesticides, but their use to protect crops is very limited due to EOs’ high instability and great volatility. Nanovectors represent a very smart alternative, and in this study, EOs from Artemisia annua (AEO) and Salvia fruticosa (SEO) were formulated into microemulsions and tested against Fusarium verticillioides. The EOs were extracted by steam distillation and analyzed by GC–MS. The main constituents of AEO were camphor, artemisia ketone, and 1,8-cineole; the main constituents of SEO were 1,8-cineole, camphor, α-pinene, and β-pinene. Artemisia ketone and 1,8-cineole were used to calculate the recovery and chemical stability of the microemulsions. The microemulsions were loaded with 10 mg/mL of EOs, and the recoveries were 99.8% and 99.6% for AEO and SEO, respectively. The sizes of the lipid phases were 255.3 ± 0.6 nm and 323.7 ± 2.3 nm for the AEO and SEO microemulsions, respectively. Activity against F. verticillioides was tested using amphotericin B as the positive control. F. verticillioides was very susceptible to both EOs. When loaded in the microemulsions, AEO and SEO remained very active at a dose of 1.4 and 1.2 mg, with a 99.99% reduction of F. verticillioides. The findings suggest AEO and SEO microemulsions are suitable carriers for the protection of crops against F. verticillioides.

The search for harmless alternative solutions to protect crops has become urgent and has recently attracted widespread attention from researchers around the world focusing on natural polyphenols, which represent a treasure chest of molecules with potent activities. Due to the low water solubility of polyphenols, microemulsions were selected as nanovectors. Curcumin and mangiferin solubility in different excipients was evaluated by HPLC. Microemulsion was developed using pseudo-ternary phase diagrams. Sizes and polydispersity of microemulsion globules were evaluated by dynamic light scattering. Activity against Fusarium verticillioides was evaluated by a microdilution method. Vitamin E acetate was selected as the oily phase, Transcutol P as cosurfactant and Tween 80 as surfactant. S_mix was composed of Transcutol P and Tween 80 in a 1:2 gravimetric ratio and combined with oil-phase vitamin E acetate at a weight ratio of 3:1. Microemulsions were loaded with 5 mg/mL of each polyphenol and recovery results were 99.5% and 99.3% for curcumin and mangiferin, respectively. Sizes of the lipid phase were 121.7 ± 29.2 nm and 172.6 ± 19.3 nm, respectively, for mangiferin and curcumin microemulsions. F. verticillioides was very susceptible to both microemulsions with a very high activity at a dose of 0.9 mg/mL (log-4 reduction), evidencing a possible use of these nanoformulations to protect crops from F. verticillioides.