Obesity and overweight are closely related to diet, and the gut microbiota play an important role in body weight and human health. The aim of this study was to explore how Lactobacillus curvatus HY7601 and Lactobacillus plantarum KY1032 supplementation alleviate obesity by modulating the human gut microbiome. A randomized, double-blind, placebo-controlled study was conducted on 72 individuals with overweight. Over a 12-week period, probiotic groups consumed 1 × 10¹⁰ colony-forming units of HY7601 and KY1032, whereas the placebo group consumed the same product without probiotics. After treatment, the probiotic group displayed a reduction in body weight (p < 0.001), visceral fat mass (p < 0.025), and waist circumference (p < 0.007), and an increase in adiponectin (p < 0.046), compared with the placebo group. Additionally, HY7601 and KY1032 supplementation modulated bacterial gut microbiota characteristics and beta diversity by increasing Bifidobacteriaceae and Akkermansiaceae and decreasing Prevotellaceae and Selenomonadaceae. In summary, HY7601 and KY1032 probiotics exert anti-obesity effects by regulating the gut microbiota; hence, they have therapeutic potential for preventing or alleviating obesity and living with overweight.

Sarcopenia is a loss of muscle mass and function in elderly people and can lead to physical frailty and fall-related injuries. Sarcopenia is an inevitable event of the aging process that substantially impacts a person’s quality of life. Recent studies to improve muscle function through the intake of various functional food materials are attracting attention. However, it is not yet known whether probiotics can improve muscle mass and muscle strength and affect physical performance. Lactobacillus plantarum HY7715 (HY7715) is a lactic acid bacteria isolated from kimchi. The present research shows that L. plantarum HY7715 increases physical performance and skeletal muscle mass in 80-week-old aged Balb/c male mice. HY7715 not only induces myoblast differentiation and mitochondrial biogenesis but also inhibits the sarcopenic process in skeletal muscle. In addition, HY7715 recovers the microbiome composition and beta-diversity shift. Therefore, HY7715 has promise as a functional probiotic supplement to improve the degeneration of muscle function that is associated with aging.

Hangovers are uncomfortable physiological symptoms after alcohol consumption caused by acetaldehyde, a toxic substance in which alcohol is metabolized by alcohol dehydrogenase (ADH). Rapid alcohol and acetaldehyde decomposition are essential to alleviate alcohol handling symptoms. This study investigated the effects of HY_IPA combined with Mesembryanthemum crystallinum, Pueraria lobata flower, and Artemisia indica on alleviating hangovers. A randomized, double-blind, parallel-group, placebo-controlled clinical study was conducted on 80 individuals with hangover symptoms. Alcohol intake was 0.9 g/bw with 40% whiskey, adjusted proportionately to body weight. The Acute Hangover Scale total score was 5.24 ± 5.78 and 18.54 ± 18.50 in the HY_ IPA and placebo groups, respectively (p < 0.0001). All nine indicators of the hangover symptom questionnaire were significantly improved in the HY_IPA group (p < 0.01). Blood alcohol and acetaldehyde concentrations rapidly decreased from 30 min in the HY_IPA group (p < 0.05). ADH and acetaldehyde dehydrogenase (ALDH) activities in the blood of the HY_IPA group were significantly higher than those in the placebo group at 0, 1, and 2 h after alcohol consumption (p < 0.01). The rapid hangover relief was due to increased ADH and ALDH. Therefore, HY_IPA effectively relieves hangover symptoms by decomposing alcohol and acetaldehyde when consumed before alcohol consumption.

Hair loss is a disease that requires accurate diagnosis and type-specific medical treatment. Many hair loss treatments have some side effects, such as hormone-related effects, so there is a need for safe and effective hair loss treatment. In this study, we investigated the effects of Lactobacillus paracasei HY7015 (HY7015) and Lycopus lucidus Turcz. (LT) extract on hair regrowth and protection. In vitro experiments were conducted to assess the effects of HY7015 and/or LT extract on human follicle dermal papilla cells (HFDPC) of cytoprotective functions such as proliferations, antioxidants, anti-inflammatory, and growth factor expressions. In animal experiments, we investigated hair regrowth rate, hair follicle formation and secretion of growth factors in telogenic C57BL/6 mice. We confirmed the cytoprotective effects of HY7015 and LT through regulations of proliferation, SOD and IL-1β in HFDPC. In mouse experiments, oral administration of HY7015 and LT promoted hair regrowth as well as hair follicle maturation in the dermal skin of C57BL/6 mice, and upregulated VEGF and IGF-1 growth factor levels in mouse serum. In summary, our data demonstrate that ingestions of HY7015 and LT can promote hair regrowth by enhancing cytoprotective effects and expressions of growth factors.

Intestinal mucosal tissues are prone to infections, often leading to inflammation. Lactic acid bacteria in the gut can modulate these inflammatory responses, but the interaction between host cells and lactic acid bacteria remains unclear. This study examines how Lactiplantibacillus plantarum HY7714 alleviates intestinal inflammation using gut-on-a-chip technology and in vitro models. Inflammation was induced using a gut-on-a-chip, and changes in cell morphology and barrier function were analyzed. Extracellular vesicles (EVs) derived from HY7714-improved intestinal cell structure repaired damage and restored tight junction integrity. Additionally, they attenuated inflammatory cytokines by regulating the MyD88/mTOR/NF-κB signaling pathway. RNA sequencing revealed downregulation of vicinal oxygen chelate (VOC) family proteins and proline aminopeptidase, both linked to inflammation and extracellular matrix interactions in skin health. Therefore, we explored the effects of HY7714 EVs on skin cells. The findings showed that HY7714 EVs reduced cytotoxicity and downregulated metalloproteinase expression in skin cells exposed to UVB radiation, indicating their potential anti-aging and anti-photoaging properties. These findings suggest that HY7714-derived EVs enhance both intestinal and skin health by reducing inflammation and improving barrier function, with potential benefits for the gut–skin axis.

Red ginseng has powerful potential for use as a prebiotic, but its use is limited due to its antibacterial activity. The aim of this study is to present panax ginseng’s endophytic lactic acid bacteria capable to overcome the antibacterial activity of red ginseng and improve their characteristic. Lactobacillus paracasei HY7017 (HY7017) was cultured in a medium supplemented with red ginseng. The probiotic properties and immune-enhancing effects of HY7017 were investigated in vitro and in vivo. HY7017 was proliferated strongly in RGE and had significantly improved properties compared with an L. paracasei type strain ATCC25302. HY7017 cultured in RGE-supplemented medium increased the production of nitric oxide, TNF-α, and IL-6 in macrophages, and increased IL-12 and IFN-γ secretion in splenocytes. Furthermore, HY7017 restored WBC counts, increased the amount of IL-2 and IFN-γ released, and enhanced the cytotoxicity of natural killer cells when orally administered to immunosuppressed mice. Moreover, HY7017 has properties that make it suitable as a probiotic, such as stability in the gastrointestinal tract and adhesion to Caco-2 cells. This study showed that HY7017 cultured with RGE may contribute to the development of probiotics to enhance immunity.