Diabetes, a chronic metabolic disorder, is characterized by persistent hyperglycemia. This study aimed to evaluate the hypoglycemic and antioxidant activities of lactic acid bacteria strains isolated from humans and food products and investigate the probiotic properties of the selected four strains. The hypoglycemic activity of the isolated strains was examined by evaluating the α-glucosidase and α-amylase inhibitory activities. The antioxidant activity was measured using the DPPH, ABTS, and FRAP assays. Four strains (Lactiplantibacillus plantarum MG4229, MG4296, MG5025, and Lacticaseibacillus paracasei MG5012) exhibited potent α-glucosidase inhibitory (>75%) and α-amylase inhibitory (>85%) activities, which were comparable to those of acarbose (>50%; 1000 μg/mL). Similarly, the radical scavenging and antioxidant activities of the four strains were comparable to those of ascorbic acid (50 μg/mL). Additionally, the probiotic properties of the four selected strains were examined based on acid and bile salt tolerance, auto-aggregation ability, and antibiotic resistance. The four strains were resistant to pH 2 (>50% of survivability) and 0.5% bile salt (>80% of survivability). Therefore, we suggest that the selected strains with hypoglycemic, antioxidant, probiotic properties can potentially prevent diabetes.

Alcohol and drug overdoses cause liver diseases such as cirrhosis, hepatitis, and liver cancer globally. In particular, an overdose of acetaminophen (APAP), which is generally used as an analgesic and antipyretic agent, is a major cause of acute hepatitis, and cases of APAP-induced liver damage are steadily increasing. Potential antioxidants may inhibit the generation of free radicals and prevent drug-induced liver damage. Among plant-derived natural materials, radishes (RJ) and turnips (RG) have anti-inflammatory, anticancer, and antioxidant properties due to the presence of functional ingredients, such as glucosinolate and isothiocyanate. Although various functions have been reported, in vivo studies on the antioxidant activity of radishes are insufficient. Therefore, we aim to evaluate the hepatoprotective effects of RG and RJ in APAP-induced liver-damaged mice. RG and RJ extracts markedly improved the histological status, such as inflammation and infiltration, of mice liver tissue, significantly decreased the levels of alanine transaminase, aspartate aminotransferase, and malondialdehyde, and significantly increased the levels of glutathione, superoxide dismutase and catalase in the APAP-induced liver-damaged mice. In addition, RG and RJ extracts significantly increased the expression of Nrf-2 and HO-1, which are antioxidative-related factors, and regulated the BAX and BCL-2, thereby showing anti-apoptosis activity. These results indicated that RG and RJ extracts protected mice against acute liver injury, attributed to a reduction in both oxidative stress and apoptosis. These findings have clinical implications for the use of RG and RJ extracts as potential natural candidates for developing hepatoprotective agents.

Radish (Raphanus sativus L.) is a representative root vegetable widely cultivated in Asia and known to have various physiological effects, such as gastric protective, anti-inflammatory, antioxidant, and hemostasis improving effects, and to ameliorate digestive disorders. However, studies on the antiobesity effects of white and red radish are inadequate. Therefore, in this study, the anti-adipogenic and anti-lipogenic effects of Ganghwa (RG) and Jeju (RJ) radishes were investigated in C3H10T1/2 cells. Lipid accumulation inhibition by Oil Red O staining and TG contents confirmed that at 1,000 μg/mL RG and RJ significantly inhibited lipid accumulation and dose-dependently reduced the mRNA and protein levels of major adipogenesis and lipogenesis-related factors. In addition, inhibition of the expression of genes in the PI3K/Akt pathway by RG or RJ markedly increased leptin and adiponectin levels. These results indicate radishes are potential functional materials that inhibit adipocyte differentiation and lipid accumulation.

A Box–Behnken Design (BBD) was employed to optimize the extraction of antioxidants from Ruby S apple peel by ultrasound-assisted extraction (UAE). The effect of extraction temperature (20–40 °C), extraction time (15–45 min), and ethanol concentration (50–90%) in water on extraction yield, total phenol content (TPC), total flavonoid content (TFC), and DPPH radical scavenging activity of Ruby S peel extracts (RPEs) were investigated. The optimized extraction conditions that maximized extraction yield, TPC, TFC, and DPPH radical scavenging ability, were temperature 20 °C, extraction time 25.30 min, and ethanol concentration 50%. The validity of designed model was verified, and experimental values obtained under optimum conditions concurred with predicted values. Hyperoside, isoquercitrin, and phloridzin, were among the major flavonoids extracted. Our findings demonstrate the suitability of UAE and RSM for the optimization of Ruby S peel extraction and suggest the potential use of RPEs as bioactive functional materials.