Yoo-Na Jeon

Cnidium officinale (CO) and Angelica gigas (AG) are traditional herbal medicines known for their bioactive compound ferulic acid (FA), which exerts skin-whitening, anti-inflammatory, antioxidant, and UV-protective effects. However, conventional extraction yields are limited and often require solvent-intensive processes. In this study, an eco-friendly hot-melt extrusion (HME) process was applied to enhance the FA content and extractability from CO and AG. Process optimization significantly improved particle morphology and reduced size, as confirmed by Fourier transform-infrared spectroscopy (FT-IR) and field emission-scanning electron microscopy (FE-SEM) analysis. Quantitative High-performance liquid chromatography (HPLC) analysis showed increased FA content in HME-treated extracts, which corresponded to enhanced biological efficacy. The HME extracts exhibited no cytotoxicity up to 500 µg/mL in B16F10 melanocytes and significantly inhibited α-melanocyte stimulating hormone (α-MSH)-induced melanin synthesis. In HaCaT keratinocytes, the HME group promoted superior wound closure at 24 and 48 h, indicating accelerated skin regeneration. These findings support HME as a sustainable and effective strategy for developing natural ingredient-based cosmetic formulations targeting hyperpigmentation and skin repair.

Bioactive molecule‐based synthesis of silver nanoparticles (AgNPs) offers an eco‐friendly approach with high therapeutic potential; however, research in this area remains limited. This study introduces hot melt extrusion (HME) technology to enhance the extraction efficiency of bioactive compounds, including astaxanthin, from the microalgae Haematococcus pluvialis (Hp). AgNPs were synthesized using HME‐processed Hp (H‐Hp/AgNPs), confirmed by a color change and UV–vis absorption spectrum. The resulting H‐Hp/AgNPs exhibited an average size of 129.7 ± 10.4 nm, a polydispersity index of 0.2 ± 0.3, and a zeta potential of −31.54 ± 0.2 mV, indicating high stability. The synthesized AgNPs demonstrated antibacterial activity by inhibiting the growth and biofilm formation of antibiotic‐resistant bacteria. Cell viability assays revealed that normal cells maintained over 100% viability at most concentrations of H‐Hp/AgNPs, while cancer cells exhibited significant cytotoxicity (34.1 ± 3.1%) at 250 μg/mL. Furthermore, H‐Hp/AgNPs induced apoptosis in MDA‐MB 231 cells, as evidenced by mitochondrial membrane potential loss, nuclear condensation, and apoptosis, confirmed through AO/EB, Rh123, and PI staining. Additionally, H‐Hp/AgNPs showed no hemolytic activity at concentrations below 250 μg/mL, ensuring safety. In conclusion, this study highlights the potential of biosynthesized H‐Hp/AgNPs as promising candidates with antioxidant, antibacterial, biocompatibility, and anticancer properties.

Synthesis of silver nanoparticles (AgNPs) using plant extracts has been proposed as a more advantageous and environmentally friendly alternative compared to existing physical/chemical methods. In this study, AgNPs were synthesized from silver nitrate using black mulberry (BM) extract. The biosynthesized AgNPs were characterized through an UV-visible spectrometer, X-ray diffraction, and transmission electron microscopy. Additionally, BM-AgNPs were subjected to antioxidant, antibacterial, anti-inflammatory, and anticancer activities. AgNPs biosynthesized from BM extract were dark brown in color and showed a strong peak at 437 nm, confirming that AgNPs were successfully synthesized. The size of AgNPs was 170.17 ± 12.65 nm, the polydispersity index was 0.281 ± 0.07, and the zeta potential value was −56.6 ± 0.56 mV, indicating that the particles were stable. The higher total phenol, flavonoid, and anthocyanin content of BM-AgNPs compared to BM extract indicates that the particles contain multiple active substances due to the formation of AgNPs. The DPPH and ABTS assays showed decreased IC₅₀ values compared to BM extract, demonstrating improved antioxidant activity. AgNPs inhibited the growth of S. aureus and E. coli at 600 μg/mL, with minimum bactericidal concentrations determined to be 1000 and 1200 μg/mL, respectively. The anti-inflammatory activity was 64.28% at a BM-AgNPs concentration of 250 μg/mL. As the concentration increased, the difference from the standard decreased, indicating the inhibitory effect of AgNPs on bovine serum albumin denaturation. The viability of MCF-7 cells treated with BM-AgNPs was found to be significantly lower than that of cells treated with BM extract. The IC₅₀ value of BM-AgNPs was determined to be 96.9 μg/mL. This study showed that BM-AgNPs have the potential to be used in the pharmaceutical industry as antioxidant, antibacterial, anti-inflammatory, and anticancer agents.

Mulberry is a rich source of anthocyanins (ACNs) known to possess biological activities. However, these ACNs are unstable in high pH, heat, and aqueous environments with a low bioavailability. In this study, a colloidal dispersion was prepared by hot melt extrusion with proper excipients. In this process, a hydrophilic polymer matrix was used to confirm the stability of the compound in high pH, high temperature, and aqueous media. It was confirmed that the particle size and the polydispersity index value were reduced, thereby improving the solubility. In vitro release studies revealed that the extrudate had a sustained release compared to a non-extruded product. As a result of measuring changes of intestinal microorganisms (Lacticaseibacillus rhamnosus, Pediococcus pentosaceus, Escherichia coli, Enterococcus faecalis, and Staphylococcus aureus), contents of probiotics were found to be increased whereas contents of pathogenic microorganisms were decreased. Thus, hot-melt extrusion could enhance the stability of ACN with prolonged release. The processed formulation exhibited probiotic properties and antimicrobial activities against pathogenic intestinal microflora.