Chan Yoo, Do Yeong Son, Dae Sung Yoo, Eun Jin Sung, Ji Won Seo, Ji Yoon Park, Seong Rok Sim, and Dae Bang Seo. Journal of the Korean Society of Food Science and Nutrition 2025;54:526-34. https://doi.org/10.3746/jkfn.2025.54.6.526

Obesity is well-known as a major risk factor for metabolic disorders, and natural compounds are being explored as alternatives to conventional therapies. While Centella asiatica is well known for its medicinal and dietary benefits, the biological activities of Giant Centella asiatica (GCA), especially when extracted with mineral-rich lava seawater, remain poorly characterized. This study aimed to evaluate the anti-adipogenic and lipid-metabolism-regulating effects of a novel GCA extract (GCA-LS-90) and its ability to stimulate GLP-1 secretion in vitro. GCA-LS-90 significantly inhibited lipid accumulation in 3T3-L1 adipocytes by up to 24.3% at 200 µg/mL (p < 0.001). It downregulated adipogenic transcription factors (C/EBPβ, C/EBPα, PPARγ) and lipogenic regulators (SREBP1c, FAS, G6PD, ME), while upregulating KLF2 (all p < 0.001). Western blotting confirmed reduced SREBP1c and SREBP2 protein expression, increased phosphorylation of AMPKα/ACC, and enhanced HSL activity (p < 0.05–0.001). In STC-1 cells, GCA-LS-90 increased GLP-1 secretion (53.5 pmol/L at 90 µg/mL vs. 41.3 pmol/L in control, p < 0.001). The major compounds, 3,5- and 4,5-di-O-caffeoylquinic acids, reproduced these effects. In conclusion, GCA-LS-90 modulated adipogenesis-, lipid-metabolism-, and GLP-1 secretion-related pathways in vitro, suggesting its potential as a functional ingredient for obesity management. Further in vivo studies are needed to confirm efficacy and translational relevance.

Ultraviolet B (UVB) irradiation is a major contributor to photoaging and hyperpigmentation, leading to collagen damage and excessive melanin accumulation. This study investigated the anti-photoaging and anti-melanogenic effects of heat-killed L. plantarum RKBP isolated from Giant Centella asiatica. L. plantarum RKBP was prepared by thermal inactivation and evaluated for anti-photoaging effects using human dermal fibroblasts and three-dimensional (3D) human skin-equivalent tissues. The anti-melanogenic effects were assessed in α-melanocyte-stimulating hormone (α-MSH)-stimulated B16F10 melanoma cells, three-dimensional melanoma spheroids, and intrinsically pigmented 3D human skin-equivalent models. MAPK/AP-1 signaling, MMP-1 expression, collagen integrity, melanin content, and melanogenesis-related protein expression were analyzed. L. plantarum RKBP selectively suppressed UVB-induced ERK/JNK phosphorylation and AP-1-mediated MMP-1 expression, preserving collagen integrity in a 3D human skin-equivalent model. Treatment with L. plantarum RKBP reduced α-MSH-induced melanin production and decreased tyrosinase expression in B16F10 cells. L. plantarum RKBP also attenuated melanin accumulation in 3D melanoma spheroids and pigmented human skin-equivalent tissues. L. plantarum RKBP exerts anti-photoaging and anti-melanogenic effects across in vitro and 3D skin models. These findings support its potential as a postbiotic skin health ingredient.

High-cell-density heterotrophic cultivation of microalgae is a promising strategy for commercial lutein production. However, maintaining reproducible and high-productivity performance during scale-up remains challenging. In this study, a scalable cultivation process for the EMS-induced high-yielding mutant Chlorella sp. HS5 was developed and validated in a 5,000 L bioreactor. Three independent batch cultivations were first conducted to confirm process reproducibility and establish a standardized baseline for scale-up. To enhance volumetric productivity, a multi-stage fed-batch strategy was then implemented. In the optimized three-stage process, full nutrient replenishment at the second feeding stage sustained high-density growth, while subsequent transient glucose limitation under nitrogen-replete conditions was associated with enhanced intracellular lutein accumulation. The final dry cell weight reached 82.3 g L−1, with a lutein content of 5.20 mg g−1 DCW and a volumetric lutein productivity of 142.4 mg L−1 d−1, corresponding to a 3.0-fold increase over the standardized batch process. These results demonstrate the technical feasibility of scalable heterotrophic production of lutein-enriched Chlorella biomass in a 5,000 L bioreactor.