The purpose of this study was to optimize conditions of solid-phase fermentation of lactic acid bacteria to enhance GABA contents in grains. Optimal solid-phase fermentation conditions that could enhance the GABA content after fermenting Oryza sativa (brown rice) were investigated by changing the Lactobacillus strain, fermentation temperature, fermentation time, and inoculated bacteria number. Avena sativa, Cicer arietinum, and red and brown Lens culinaris were then fermented using the optimal solid-phase fermentation conditions to measure changes in GABA content and antioxidant activity. As a result of the experiment, the optimal solid-phase fermentation conditions to enhance the GABA contents in grains were: fermentation time, 48 h; amounts of bacteria, inoculating 5% of 1 × 10⁷ CFU/mL of lactic acid bacteria; and fermentation temperature, 36 °C. When fermented under this condition, the GABA content increased from 4.64 mg/g to 6.93 mg/g (49.0%) compared to unfermented raw material. The results of the DPPH and ABTS radical scavenging activity assays confirmed that both the GABA content and radical scavenging activity were increased after fermentation. Such solid fermentation conditions developed in this study can be used to support the development of health functional food materials with enhanced GABA content and antioxidant activity.

Late-onset hypogonadism (LOH) is an age-associated condition characterized by a progressive decline in testosterone levels. It manifests as reduced libido, infertility, muscle loss, and cognitive impairment in middle-aged men. Although testosterone replacement therapy is effective, its associated side effects highlight the need for safer alternatives. Previously, we have demonstrated the efficacy of the fermented Morinda citrifolia extract (FME) in ameliorating LOH symptoms in vitro. The present study aimed to assess the in vivo efficacy of FME in mitigating LOH symptoms using an aged rat model. Thirty-three-week-old male Sprague-Dawley rats were administered either Testofen or FME daily for four weeks. Serum levels of total and free testosterone, sex hormone-binding globulin (SHBG), dihydrotestosterone, and metabolic hormones were measured. Testicular gene expression and protein expression related to steroidogenesis were also assessed. Muscle mass, physical performance (evaluated using treadmill test), and sperm quality were also assessed. FME treatment significantly increased serum testosterone levels, reduced SHBG and dihydrotestosterone concentrations, and enhanced the expression of testosterone biosynthesis-related proteins. FME downregulated degradation enzymes such as 5α-reductase and aromatase. FME also improved sperm production, progressive motility, muscle mass, and treadmill running capacity. Histological analyses confirmed tissue recovery in the testes and muscles. FME alleviated LOH-related symptoms in aged rats by modulating testosterone metabolism, enhancing reproductive and physical health, and maintaining a favorable safety profile. These findings validate the in vivo efficacy of FME and highlight its potential as a natural therapeutic candidate for managing LOH and related conditions.

Late-onset hypogonadism (LOH) is an age-related condition characterized by declining testosterone levels and impaired reproductive and metabolic functions. Fermented Morinda citrifolia extract (FME) has demonstrated therapeutic potential against LOH; however, its active constituents and underlying mechanisms remain unclear. The aim of this study was to identify the key bioactive compounds in FME and evaluate their efficacies and mechanisms of action in alleviating LOH. High-performance liquid chromatography (HPLC) was used to quantify the iridoids and coumarins in FME. Among these four candidates, monotropein (MON) was selected for functional evaluation. In vitro assays using TM3 Leydig cells were used to assess the effects of MON on steroidogenic gene and protein expression under oxidative stress. In vivo studies involved oral administration of MON (40 mg/kg/day) to aged Sprague-Dawley rats for 4 weeks. Hormonal, histological, reproductive, metabolic, and safety parameters were measured. MON significantly restored testosterone production and upregulated key steroidogenic enzymes (StAR, 3β-HSD2, 17,20-desmolase, and 17β-HSD3) in vitro and in vivo. It improved serum testosterone levels, spermatogenesis, and sperm motility in aged rats. MON also reduced age-associated increases in total cholesterol and triglyceride levels without altering luteinizing hormone, follicle-stimulating hormone, or estradiol, and without inducing hepatic, renal, or prostate toxicity. MON was identified as the principal active compound of FME responsible for its LOH-alleviating effects. MON enhanced testicular steroidogenesis and improved reproductive and metabolic outcomes without causing systemic toxicity, supporting its potential as a targeted phytotherapeutic agent against age-related androgen deficiency.

Morinda citrifolia (Noni) is a traditional medicinal plant widely utilized in tropical regions for its antioxidant and anti-inflammatory properties. While its traditional applications extend to skin and hair health, its specific pharmacological effects on hair follicle biology-particularly when its phytochemical profile and bioavailability are enhanced through fermentation-remain largely unexplored. This study aimed to investigate the pro-regenerative effects and underlying molecular mechanisms of fermented M. citrifolia extract (FME) as a potential therapeutic intervention for hair loss. The pharmacological effects of FME were evaluated using human dermal papilla cells (hDPCs) and ex vivo human hair follicle organ cultures. Assessments included cell viability, cell cycle progression, protein expression analysis, hair shaft elongation, and transcriptomic profiling. FME significantly enhanced hDPC viability and promoted cell cycle progression into the S-phase. Mechanistically, FME activated Wnt/β-catenin signaling by stabilizing β-catenin, thereby increasing the secretion of key hair growth factors (VEGF, bFGF, IGF2) and enhancing antioxidant defense. In ex vivo cultures, FME induced dose-dependent hair shaft elongation, prolonged the anagen phase, and preserved hair bulb architecture. Transcriptomic profiling revealed that FME upregulated stemness-related and hair structure pathways while downregulating matrix remodeling enzymes and pro-inflammatory signaling networks. FME promotes hair growth through the activation of dermal papilla cells and modulation of follicular signaling networks, primarily via the Wnt/β-catenin axis. These findings provide mechanistic evidence supporting FME as a promising and safe therapeutic candidate for alopecia.