Table 1.
Irritation scores of the hen’s egg-chorioallantoic membrane (HET-CAM) test.
Fig 1.
Pseudo-ternary phase diagrams of the microemulsion composed of (A) soybean oil and coconut oil (1:1) – cremophor RH40 and PEG 400 (3:1) – water, and (B) soybean oil and coconut oil (1:1) – tween 80, span 80, and PEG 400 (3:1:1) – water.
Fig 2.
Droplet size and size distribution of the microemulsion containing mango seed kernel extract and lemongrass essential oil.
Fig 3.
TEM image of the microemulsion containing mango seed kernel extract and lemongrass essential oil. Scale bar: 0.1 μm.
Table 2.
Stability data (3 months storage at room temperature) of the microemulsion-based hydrogel containing mango seed kernel extract (polyphenol as the biomarker) and lemongrass essential oil (citral as the biomarker).
Fig 4.
In-vitro Franz-cell cumulative drug release (%), in terms of the total polyphenol content (representing the mango seed extract) and citral (representing the lemongrass oil), of the microemulsion-based hydrogel (n = 3).
The initial total amount of the polyphenol content and citral in the hydrogel was ~5560 μg and ~3.6 μg, respectively.
Fig 5.
Photographs of HET-CAM test results, the positive control is sodium dodecyl sulfate 1% w/v (irritation score of 15), the negative control is NaCl 0.9% w/v (irritation score of 0), and the hydrogel sample is the microemulsion-based hydrogel containing mango seed kernel extract and lemongrass essential oil (irritation score of 0).
Fig 6.
(A) LPS-induced RAW 264.7 cell NO production inhibitory percentages and (B) biofilm formation reduction percentages on Cutibacterium acnes of the blank hydrogel (hydrogel with no extract/oil), the hydrogel containing mango seed kernel extract and lemongrass essential oil, and the commercial product Klenzit-C® (n = 3). * denotes significant different between the hydrogel and Klenzit-C®.