To improve the functional properties of mulberry leaves, γ-aminobutyric acid (GABA) enrichment treatments were applied. The results showed that the combined treatment of sodium glutamate immersion, cold shock, and anoxic significantly increased the GABA content. HPLC analysis displayed that the quantity of some active phenolics was significantly increased after the treatment. The GABA-enriched mulberry leaf powders were subsequently prepared, and it was found that as the particle size decreased, their water and oil holding capacity and their swelling power decreased, while the angle of repose increased. The dissolution rate of GABA and total phenolics increased as the particle size decreased. Optical observations and SEM results revealed that the fiber structures of the particles were gradually destroyed as the particle size decreased. Further, FTIR analysis showed that the active compounds in the powders were not destroyed. M400 and M140 powder showed the maximum DPPH radical scavenging ability and AGEs inhibition capacity, respectively. Additionally, adding the powders effectively alleviated the staling of bread without any significant effect on taste.

In the present study, the hypoglycemic effects of wheat bran alkyresorcinols (ARs) were investigated in type 2 diabetes mellitus (T2DM) mice induced by a high-fat/high-sucrose diet (HFSD) combined with low dose streptozotocin (STZ). After the consumption of 5 mg kg⁻¹ d⁻¹ acarbose (positive control) and different doses of wheat bran ARs (50, 200 and 500 mg kg⁻¹ d⁻¹) for 4 weeks, the fasting blood glucose (FBG) levels in T2DM mice were found to be reduced significantly (p < 0.05), and the effects of 200 and 500 mg kg⁻¹ d⁻¹ administration were better than that of 50 mg kg⁻¹ d⁻¹. The results of the oral glucose tolerance test (OGTT) also showed that both acarbose and AR administration significantly increased the glucose tolerance of the T2DM mice. Then, the fasting serum insulin levels (FINS) were significantly reduced by AR treatment, and the effect of 500 mg kg⁻¹ d⁻¹ AR administration was better than that of 5 mg kg⁻¹ d⁻¹ acarbose. The profile of plasma lipids was analyzed simultaneously, and the results showed that the contents of total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) were significantly decreased, while the content of high-density lipoprotein cholesterol (HDL-C) was increased significantly after 200 and 500 mg kg⁻¹ d⁻¹ AR treatment (p < 0.05). Furthermore, 200 and 500 mg kg⁻¹ d⁻¹ ARs significantly increased the content of hepatic glycogen and the activity of glucokinase (p < 0.01) in T2DM mice. The relative mRNA levels of glucose transporter 2 (GLUT2) in the liver tissue were increased markedly in 200 and 500 mg kg⁻¹ d⁻¹ AR treatment groups (p < 0.01), and the relative mRNA levels of glucose transporter 4 (GLUT4) in the epididymal adipose tissue were increased significantly in all AR treatment groups, especially significantly higher than acarbose (p < 0.01). Histological analyses revealed that treatment with ARs exerted a protective role on pancreatic β-cells. The results indicated that ARs could be an effective hypoglycemic active ingredient in whole grain diets.

Mulberry leaves contain polysaccharides, phenols, alkaloids, and other active ingredients which have medicinal and edible value. In this study, fermented mulberry leaf powder was prepared by solid-state fermentation using Pediococcus pentosaceus JC30. The effects of the fermentation on the phytochemical, flavor characteristics, phenolics, and antioxidant activity of mulberry leaves were studied. The results showed that the content of γ-aminobutyric acid in fermented mulberry leaf powder (FMLP) increased by 6.73-fold and the content of phytic acid decreased by 11.16%. Ultra-high-performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) analysis showed that the fermentation of Pediococcus pentosaceus JC30 altered the phenolic composition of mulberry leaves, increasing the total free phenolic content by 88.43%. In particular, the contents of free phenols such as leucocyanidin, myricetin, and quercetin increased significantly and were positively correlated with antioxidant capacity. The fermentation of Pediococcus pentosaceus JC30 significantly enhanced the scavenging ability of DPPH free radicals, hydroxyl radicals, and the total reducing ability of mulberry leaves. Gas chromatography ion mobility spectrometry (GC-IMS) analysis showed that FMLP has an intense fruity and floral aroma, while having less grassy and earthy odor. The fermentation improved the phytochemical, flavor, and nutritional value of mulberry leaves, which provides more possibilities for the development of mulberry leaf products outside the sericulture industry.

A γ–aminobutyric acid (GABA)–producing strain JC30 was isolated from traditional kimchi, which was identified as Pediococcus pentosaceus by 16S rDNA sequencing. P. pentosaceus JC30 was highly tolerant to acid, bile salt, and high temperatures. The survival rate of JC30 in MRS medium (pH 2.5) for 3 h was 60.96 %. Furthermore, the survival rate of JC30 in MRS medium with 3 mg/mL bile salt for 24 h was 86.62 %. The survival rate of JC30 in MRS medium at 56 °C and 58 °C for 10 min was 97.17 % and 78.20 %, respectively. When 2 % v/v JC30 (8.0 log10 CFU/mL) was added to prepare sourdough and the sourdough was then used to make bread, the bread had a higher specific volume (5.13 ± 0.12 mL/g) and GABA content (3.32 ± 0.04 mg/g DW) than the control.

Bombyx batryticatus is the dried body of silkworm (Bombyx mori Linnaeus) larvae infected with Beauveria bassiana. It is widely used in traditional Chinese medicine for treating convulsions, epilepsy, and hyperglycemia. In this study, Bombyx batryticatus and its extract were prepared. The total reducing power, hydroxyl radical scavenging and superoxide anion radical scavenging activities, as well as the α-glucosidase inhibitory activity of Bombyx batryticatus extract were superior to those of normal silkworm larvae extract. Among them, the IC₅₀ value of Bombyx batryticatus extract for α-glucosidase was 5.76 mg/mL, while that of normal silkworm larvae extract was 7.0 mg/mL. Untargeted metabolomic analysis was employed to compare the material composition of normal silkworm larvae and Bombyx batryticatus. The results revealed 101 metabolic differences between the two groups, including a significant increase in fatty acids and their derivatives in the Bombyx batryticatus extract. Further separation and purification of the Bombyx batryticatus extract were performed using solvents of varying polarity. The chloroform fraction exhibited the highest inhibitory activity against α-glucosidase, with an IC₅₀ value of 0.217 mg/mL. LC-MS further identified compounds in the chloroform fraction, suggesting that those alkaloids, fatty acids, and their derivatives may be responsible for its strong α-glucosidase inhibitory activity. This study elucidates the material basis underlying the pharmacological effects of Bombyx batryticatus, particularly its hypoglycemic components, thereby providing critical experimental support for its future development and application in medicine.

Cordycepin is a key active component of Cordyceps militaris, but the molecular mechanism underlying temperature-regulated biosynthesis remains unclear. In this study, Cordyceps militaris strain KN-1 was used as experimental material, with low-temperature (15 °C), control (20 °C), and high-temperature (25 °C) treatments applied during the fruiting body stage. Transcriptomics, untargeted metabolomics, weighted gene co-expression network analysis (WGCNA), and Reverse Transcription quantitative PCR (RT-qPCR) validation were integrated to elucidate the molecular mechanism of temperature-mediated cordycepin biosynthesis. The results showed that 25 °C increased fruiting body cordycepin content by 84%, while 15 °C reduced it. Transcriptomic analysis identified differentially expressed genes (DEGs) enriched in transmembrane transport and fatty acid metabolism, and untargeted metabolomics revealed differential metabolites (DAMs) enriched in lipids and organic acids, indicating that temperature primarily affects Cordyceps militaris membrane function. WGCNA showed that the MEblue module was positively correlated with cordycepin (r = 0.93), with Major Facilitator Superfamily (MFS) members accounting for the highest proportion (47.1%) that may affect cordycepin transmembrane transport. Multi-omics analysis indicated that high temperature promotes cordycepin accumulation through the synergistic regulation of multiple pathways: upregulating genes in the pentose phosphate pathway, purine metabolism, and cordycepin biosynthetic gene cluster (Cns1–Cns3), increasing protective agent pentostatin content, downregulating cordycepin-degrading genes, and enhancing cordycepin transmembrane transport. This study clarifies the molecular mechanism of temperature-mediated cordycepin accumulation, providing a theoretical basis for improving cordycepin production via temperature regulation, optimizing Cordyceps militaris strain quality, and facilitating efficient industrial production.