Investigation of Antioxidant Extracts from Etlingera Elatior Flowers and Citrus Reticulata Blanco Peels through Optimized Microwave-Assisted Extraction for Anti-Acne Potential of Skincare Serum and Face Mask Formulation

Abstract

This study aimed to develop skincare serum and face mask formulations for acne treatment using extracts from Etlingera elatior flowers and Citrus reticulata blanco peels. Extracts were prepared through Microwave-Assisted Extraction (MAE), and the optimal extraction conditions for phenolic compounds from Etlingera elatior flowers were determined. The total phenolic content (TPC) of the extracts was quantified, and their antioxidant activities were evaluated. Furthermore, the antibacterial activity of Etlingera elatior flower extract against Cutibacterium acnes was assessed using the disc diffusion method. The optimal extraction condition for phenolic compounds from Etlingera elatior flower powder was identified as follows: 4 g of flower powder with 40 mL of ethanol as the solvent, under microwave power of 400 W for one 30-second cycle. This condition yielded an extract with a TPC of 0.51 ± 0.03 mg GAE/g extract. For Citrus reticulata blanco peel extract, the TPC was 0.24 ± 0.05 mg GAE/g extract. Antioxidant activity analysis revealed that Etlingera elatior extract and Citrus reticulata blanco peel extract exhibited notable free radical scavenging activity, with IC₅₀ values of 56.85 ± 2.25 µg TAE/mL and 1,249.59 ± 78.67 µg TAE/mL, respectively. Additionally, Etlingera elatior extract demonstrated significant inhibitory effects against Cutibacterium acnes, comparable to standard substances commonly employed in acne treatment. Stability testing confirmed that the prototype skincare serum formulation exhibited favorable stability. These findings indicate that the developed formulations incorporating Etlingera elatior flower and Citrus reticulata blanco peel extracts can be utilized to produce prototype skincare serum and face mask products depending on the users’ needs. Such formulations not only offer potential efficacy in acne management but also contribute to value-added utilization of these distinctive local plant resources.