Fermentation of Asparagus cochinchinensis extracts with endophytic Aspergillus aculeatus TD103 enhanced their photo-protective effects against UVB radiation.

Ultraviolet B (UVB) radiation severely damages human skin by causing DNA damage, oxidative stress, and collagen degradation. This study explored the photoprotective properties of Asparagus cochinchinensis extracts fermented with endophytic fungus Aspergillus aculeatus TD103. Compared to the unfermented control, TD103-fermented A. cochinchinensis demonstrated stronger radical scavenging and ferric ion reduction abilities in vivo, significantly reduced intracellular reactive oxygen species (ROS) and increased the antioxidant enzymes including heme oxygenase-1 (HO-1), superoxide dismutase (SOD), and catalase (CAT) in UVB-induced HaCaT cells. It also downregulated the expression of the AP-1 and MMP genes, reduced the content of matrix metalloproteinase (MMP-1) and increased type I procollagen amino-terminal propeptide (PINP) levels in UVB-induced HaCaT cells. Non-targeted metabolomics and HPLC quantification revealed that elevated sarsasapogenin content may critically contribute to enhanced photoprotective capacity in Asparagus cochinchinensis. The safety assessment of fungus TD103 revealed that this strain was not drug resistant and did not produce mycotoxins, thereby indicating its safety for application. Eye irritation tests demonstrated the safety profile of the fermented extract, indicating negligible irritant potential. The TD103-mediated fermentation markedly potentiated the photoprotective capacity of A. cochinchinensis, ​providing a viable biotechnological platform for sustainable cosmeceutical development targeting UV-induced skin damage.