Kombucha, a functional beverage rich in glucuronic acid, is fermented in the presence of acetic acid bacteria and yeast as the primary microorganisms. Glucuronic acid is recognized for its various physiological benefits, such as detoxification, antioxidation, and anti-inflammation. To optimize the glucuronic acid content in kombucha, various strain combinations by selecting fermented sources were accomplished. According to the experimental results, kombucha produced through co-fermentation with Pichia anomala and Komagataeibacter hansenii, with glucose-added black tea as the carbon source, exhibited the highest glucuronic acid production. A response surface methodology found that under optimized conditions of a 12.27% (w/v) carbon source concentration, a 10.07% (w/v) substrate concentration, and a 28.4 °C temperature, the highest glucuronic acid production reached 80.16 g/L, which represented a 2.39-fold increase compared to the original kombucha. Furthermore, the total polyphenol content increased by 3.87-fold, while DPPH and ABTS free radical–scavenging capacities increased by 1.86- and 2.22-fold, respectively. To sum up, these observations reveal the potential for commercial production of glucuronic acid–enriched kombucha and contribute to the development of functional food products related to kombucha in the future.

Ganoderma formosanum, an edible medicinal fungus renowned for its bioactive metabolites, faces challenges in traditional cultivation due to prolonged timelines and elevated costs, hindering its integration into functional food formulations. This study introduces an innovative, sustainable fermentation platform by immobilizing G. formosanum mycelia (GFM) on plastic composite support (PCS) within an airlift bioreactor, utilizing agricultural byproducts to foster eco-efficient production of natural anti-melanogenesis compounds with potential as functional food ingredients. Initial shake-flask evaluations identified the SY-PCS matrix, comprising soybean hulls, polypropylene, and yeast extract, as optimal for mycelial immobilization, yielding anti-melanin activity equivalent to 79.78% of kojic acid (KA) efficacy. Upscaling to a 5 L bioreactor with 1% SY-PCS supplementation on day 8 elevated this to 81.7% of KA's potency, while repeated-batch fermentation amplified second-batch biomass productivity by 2.7-fold, promoting resource-efficient yields suitable for food-grade applications. Cell-based assays in B16-F10 models demonstrated potent suppression of intracellular melanin accumulation, akin to KA, and zebrafish trials revealed a 31% reduction in melanin content. LC-MS/MS analysis identified 15 bioactive compounds, corroborated by molecular docking studies showing enhanced tyrosinase-binding affinities and synergistic effects, underscoring their promise as natural additives in functional foods for skin health support.

Age-related macular degeneration (AMD) is a leading cause of blindness in the elderly, with oxidative stress a major causative factor. Orange peel, rich in polyphenols and flavonoids, possesses potent antioxidant and anti-inflammatory activities. This study evaluated the protective effects of an ultrasound-assisted aqueous extract (OPWE) of orange peel and its major components, hesperidin and hesperetin, against sodium iodate (NaIO₃)-induced retinal damage. Component identification was performed using 3D-HPLC and LC/MS, and the antioxidant capacity was determined using the DPPH and ABTS assays. In vitro, OPWE reduced oxidative stress, mitochondrial dysfunction, and apoptosis in NaIO₃-treated ARPE-19 cells through the PI3K/Akt and HIF-1α/BNIP3 pathways. Notably, hesperetin exhibited comparable protective effects to OPWE, restoring cell viability and inhibiting ROS production. In vivo, oral administration of OPWE maintained retinal morphology and function in mice induced by NaIO₃. These findings suggest that OPWE, especially hesperetin, is a promising natural candidate for preventing oxidative stress-related retinal degeneration and maintaining retinal health.

Oxidative stress is a major contributor to the development of age-related macular degeneration (AMD), and excessive oxidative stress can induce retinal pigment epithelium (RPE) dysfunction, apoptosis, and retinal degeneration. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (NOX2) is a major enzymatic source of reactive oxygen species (ROS); however, its mechanistic role in sodium iodate (NaIO₃)-induced oxidative injury remains unclear. Tetrahydrocurcumin (THC), the major metabolite of curcumin, exhibits potent antioxidant and cytoprotective activities, but its protective effects against AMD-associated retinal degeneration have not been fully elucidated. In the present study, we investigated whether THC protects against NaIO₃-induced ROS-mediated apoptosis in RPE cells through regulation of NOX2 signaling. In vitro, THC significantly attenuated NaIO₃-induced cytotoxicity and prevented apoptosis by suppressing hydrogen peroxide (H₂O₂) production and intracellular ROS accumulation in ARPE-19 cells. THC also preserved mitochondrial membrane potential by inhibiting the Src/p47^phox/NOX2 signaling pathway and subsequently attenuated mitochondria-mediated apoptotic signaling. Furthermore, THC markedly reduced the expression of apoptotic proteins, including Bax, cleaved caspase-3, and cleaved PARP, concomitantly with suppression of Ras/Raf/MEK/ERK signaling. Mechanistically, treatment with the selective NOX2 inhibitor GSK2795039 significantly attenuated NaIO₃-induced ROS accumulation and mitochondrial depolarization, while co-treatment with THC further enhanced these protective effects. In vivo, THC ameliorated NaIO₃-induced retinal structural abnormalities by preserving the outer nuclear layer (ONL), reducing caspase-3 expression, and improving pupillary light responses in mice. Collectively, these findings demonstrate that THC protects against NaIO₃-induced retinal degeneration through suppressing NOX2-dependent oxidative stress and downstream Ras/Raf/MEK/ERK-mediated apoptotic signaling, highlighting its potential as a therapeutic candidate for AMD and other oxidative stress-related retinal disorders.

Wound healing is a complex process involving coordinated actions of multiple cell types. Therefore, when developing therapeutics to promote wound healing, it is essential to consider the synergistic contributions of various cells at different stages of the healing process. In this study, we evaluated the potential of different extracts of Botryocladia leptopoda as wound-healing agents by examining their effects on antioxidant activity, cytotoxicity, cell migration, anti-inflammatory properties, and expressions of specific biomarkers associated with wound healing. Results indicated that the ethanol extract (FE) and alkaline extract (AE) showed great antioxidation abilities against DPPH and FICA. In addition, the FE and AE provided anti-inflammatory actions that inhibited tumor necrosis factor (TNF)-α and interleukin (IL)-6 in lipopolysaccharide (LPS)-treated RAW 264.7 cells. Further analyses suggested that the FE and AE enhanced cell proliferation and migration, and regulated would healing-related genes including matrix metalloproteinase 1 (MMP1), MMP2, MMP9, and tissue inhibitor of metalloproteinase 2 (TIMP2) to avoid scar formation and accelerate wound healing. Taken together, these findings indicated that the FE and AE from B. leptopoda exhibited remarkable in vitro wound-healing properties, highlighting their potential for applications in pharmaceutical industries and health food development.