3.2. Preparation of Aloe Vera (AV) Extract and Thyme Extract

Fresh Thyme plants were purchased in August from a local store in Jordan. They were washed several times with distilled water to remove dust and soil, and then twice with absolute ethanol. The leaves were dried for 1 h at ambient temperature, and then 100 mg of a fresh Thyme plant consisting of leaves and stems was cut into pieces. These pieces were immediately transferred into a sterile, brown glass bottle with a screw cap. We added 100 mL of absolute ethanol, sealed the glass bottle, and stored it at ambient temperature in darkness for 3 months as part of a maceration. The macerate extract was then stored in a fridge at 3 °C under darkness for further use.

The leaves of the Aloe Vera (Aloe barbadensis Miller) plant were harvested during December from the botanical garden of Ajman University in the morning hours [34,35,36]. Within 10 min, the leaves with lengths of 35 to 50 cm were washed with water, then rinsed many times with distilled water, followed by absolute ethanol, then several times with ultrapure water, and finally left to dry for 1 h. After being dried, the AV leaves were cut with a sterile knife to be able to collect the mucilaginous gel in a sterile beaker. Then, the gel was transferred to a sterile mixer, mixed for 20 min until the gel was homogenized, and finally centrifuged at 4000 rpm for 40 min (3K 30; Sigma Laborzentrifugen GmbH, Osterode am Harz, Germany). The supernatant had a light-yellow color, was transferred immediately into a sterile brown bottle with a screw cap, and was stored in the fridge at 3 °C in darkness.