Rotavapor r 300

Five hundred grams (500g) of powder were macerated, respectively, with 3 L of ethanol (70% ethanol-30% water), methanol, and water for 2 days. The macerate obtained was filtered and evaporated using a rotary evaporator (BUCHI Rotavapor R-300) at 50°C. After that it was dried in an oven (Heratherm oven). The extracts obtained either hydroethanolic (HEC), methanolic (MEC), or aqueous (AEC) were preserved and used for the determination of compounds and antioxidant activity.

The extracts of the samples were prepared in methanol at a ratio of 1:25 (w/v) as described by Talhaoui et al. (2014 (link)). The collected extracts were dried under vacuum using a rotary evaporator (Buchi Rotavapor® R‐300) and kept dry for further analysis.

The fruits of R. aculeata were purchased from a local market in Veracruz, Mexico. The taxonomic validation was confirmed by an expert at the Herbarium of the Facultad de Ciencias Biológicas y Agropecuarias, Universidad Veracruzana, who assigned the registration number JLBT2 (VER). Subsequently, the fruits were subjected to washing, and the various components were segregated to isolate the seeds. These seeds were thoroughly cleaned, air-dried for a period of 7 days at room temperature, and subsequently pulverized using a manual grinder. The extraction process was carried out through maceration of the seed material at room temperature with a 1:10 (w/v) proportion of ethanol (Sigma-Aldrich)-water (80:20). Over a span of 3 days, the contents were allowed to settle, and the solvent was collected and subjected to filtration to eliminate solid residues. The extract was subsequently concentrated under vacuum conditions using a Rotavapor R-300 (Buchi®) set at 26 °C. Ultimately, the extract was subjected to lyophilization and stored for further use.

A simple thin-film rehydration method was used to prepare micelles of Pluronic F127 and Cremophor EL. The procedure is schematically presented in the Figure 1.
Suitable amounts of surfactants or surfactant mixtures were dissolved in ethanol in a round-bottom flask. The vial was attached to a rotatory evaporator (Rotavapor-R-300^®, Buchi Labortechnik AG, Flawil, Switzerland) and heated at 45 °C under vacuum to produce a thin film of micelle forming material deposited on the walls. After the total removal of the solvent, the required volume of distilled water was added to rehydrate the film under moderate magnetic stirring at 45 °C, for 30 min. The as prepared micellar dispersion was further filtered through sterile syringe filter Minisart^® 0.2 µm (Sartorius, Gottingen, Germany). For the mixed micelles, the two surfactants were added in ethanol solvent to obtain molar ratio 0.2, 0.4, 0.6 and 0.8 in the final aqueous dispersions.
The drug loaded pure and mixed micelles were prepared following the same procedure and Norfloxacin was dissolved together with the polymeric surfactants in alcohol. The dissolution of the Norfloxacin in the deposited thin film before the rehydration step ensure the maximum solubilization of the drug inside the micelle core.

The antioxidant activity was determined by two different assays: scavenging of DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) free radicals and TEAC (Trolox equivalent antioxidant capacity). The hydroalcoholic macerate of P. caerulea aerial parts was evaporated while using a Rotavapor^® R-300 (Büchi, Flawil, Switzerland), and the exact quantities were re-solubilized while using the recommended absolute alcohols. All of the assays were performed in triplicate. All of the reagents used were analytical-grade reagents purchased from Sigma–Aldrich (Merck Group).