To investigate the impact of compound microbial fermentation on Gastrodia elata quality (fermented liquid), providing a theoretical foundation for its industrial deep processing. Gastrodia elata was fermented using a compound microbial consortium (Lactobacillus plantarum, Acetobacter pasteurianus, and Wickerhamomyces anomalus, FJ group), with unfermented (CK) and enzymatically hydrolyzed (MJ) groups as controls. Physicochemical properties (total acidity, pH, etc.) were assessed. HPLC analyzed gastrodin, p-hydroxybenzyl alcohol, determined total phenols, and total flavonoids, evaluated their antioxidant and hypoglycemic activities. Volatile compounds and differential metabolites were identified using SPME-GC-MS. Sensory evaluation assessed overall quality and flavor. The results showed that compared to CK, FJ significantly increased total acidity (2.6-fold), decreased pH, and elevated the content of crude polysaccharides (247.65±16.10 mg/g) and ethanol (0.54%vol±0.02%vol). MJ showed minimal physicochemical changes except in polysaccharides. HPLC revealed that microbial fermentation enhanced the production of bioactive compounds (gastrodin, p-hydroxybenzyl alcohol), significantly increased total phenols (promoted 29.45% vs. CK), total flavonoids (promoted 44.08% vs. CK), antioxidant activity, and hypoglycemic activity (FJ>MJ>CK). SPME-GC-MS identified increased alcohols, acids, and esters in FJ, with characteristic differential metabolites including 3-penten-2-one, isoamyl alcohol, phenethyl alcohol, and ethyl acetate. Sensory evaluation confirmed improved quality, imparting distinct alcoholic and sweet notes. These results provide that compound microbial fermentation effectively enhances the bioactive components, functional properties, and sensory quality of Gastrodia elata, offering valuable insights for developing functional foods and advancing its industrial processing.

In this study, the effects of different treatment times (40, 50, 60 s) on the changes of physicochemical properties and enzyme activities of postharvest fresh-cut Dendrocalamus brandisii (D. brandisii) shoots during storage were investigated using dielectric barrier discharge-cold plasma (DBD-CP). The results showed that DBD-CP improved the brightness of fresh-cut D. brandisii shoots with the highest contents of total phenols, total flavonoids, soluble proteins, and soluble sugars compared with CK group. At the 30th day of storage of CP₁, CP₂, and CP₃-treated D. brandisii shoots, peroxidase activity decreased by 11.13, 15.96, and 5.03 U/g (P<0.05), polyphenol oxidase activity decreased by 0.28, 1.21, and 0.62 U/g (P<0.05), phenylalanine deaminase activity decreased by 1.99, 7.19, and 5.81 U/g (P<0.05), 4-coumaroyl-coenzyme A ligase activity decreased by 3.17, 4.41, and 1.81 U/g (P<0.05), pectin content increased by 23.61%, 58.33%, and 44.44% (P<0.05), and cumulative synthesis of cellulose and lignin decreased by 7.81, 37.24, and 13.86 mg/g (P<0.05), 0.54, 0.68, and 0.55 mg/g (P<0.05), respectively. Principal component analysis showed that CP₂ had the smallest confidence circle, indicating that it had the best quality stability of D. brandisii shoots. This study provides some theoretical basis for the application of DBD-CP technology in the field of postharvest preservation and processing of D. brandisii shoots.

This study aimed to elucidate the molecular mechanisms by which basic amino acids (L-arginine/L-Arg, L-lysine/L-Lys, L-histidine/L-His) regulated oxidation resistance and gel network formation in yak meat myofibrillar protein (MP). Different concentrations (0.08%, 0.15%, 0.30%, 0.60%, w/v) of each amino acid were added to the MP system. Changes in structural properties (solubility, turbidity, surface hydrophobicity, secondary and tertiary structures) and oxidation indicators (carbonyl content, total and active sulfhydryl content) of MP, as well as gel properties (water-holding capacity, cooking loss, whiteness, strength, rheological behavior), were systematically analyzed. Results demonstrated that basic amino acids synergistically improved gel performance by neutralizing charges to reduce intermolecular repulsion, inducing conformational unfolding to expose hydrophobic groups and active sulfhydryls, and regulating secondary structures (L-Lys/L-Arg promoted α-helix to β-sheet conversion, while L-His maintained concurrent increases in both), but their effects exhibited concentration and type dependencies. In beneficial aspects, L-Lys and L-Arg significantly enhanced solubility (86.38% for 0.60% L-Arg,~25% higher than control) and reduced turbidity (suppressing aggregation). These structural optimizations combined with disulfide crosslinking from exposed active sulfhydryls formed uniform gel networks, specifically increasing water-holding capacity by~25% (L-Lys/L-Arg groups at 0.30%) and reducing cooking loss (58% reduction for 0.30% L-Lys), while significantly enhancing storage modulus G' at high temperatures (≥70 ℃, L-Lys≥0.30%, L-Arg 0.60%). L-His acted mildly, mainly increasing gel strength by 4.2% at 0.60% concentration via stabilizing α-helix/β-sheet coexistence. L-Lys and L-Arg reduced gel whiteness with increasing concentration. High concentrations (especially 0.60% L-Arg) intensified protein oxidation damage (peak carbonyl content: 5.54 nmol/mg) due to excessive unfolding and self-oxidation. In summary, L-Arg and L-Lys showed advantages in optimizing solubility, inhibiting aggregation, and promoting crosslinking through charge interactions and structural transformation, serving as effective strategies for improving gels of high-myoglobin, low-fat yak meat MP, yet requiring concentration control to balance oxidation risks. L-His provides a milder alternative. Practical applications can select amino acid types based on product requirements, offering a theoretical basis for developing low-sodium, low-phosphorus yak meat products.

This study aimed to investigate the effects of different heat treatment methods (atmospheric pressure cooking, high-pressure cooking, atmospheric pressure steaming, high-pressure steaming, and microwave heating) and time (2 to 10 minutes) on the quality of Antarctic krill. The results showed that under the same heating time, the heat treatment loss rate of atmospheric pressure steaming was the lowest, and it was significantly lower than the other four methods within 6 minutes (P<0.05). Microwave heating performed best in terms of crude protein, crude fat, astaxanthin content, L^*, b^* values, and sensory scores, while atmospheric pressure cooking had the highest a^* value. As the heating time increased, the heat treatment loss rate of all five methods rose, and the differences were significant within 6 minutes (P<0.05), the contents of crude protein and crude fat decreased, and there was no significant difference within 6 minutes and 8 minutes or more (P>0.05), but the difference between 6 and 8 minutes was significant (P<0.05), the astaxanthin content and sensory scores first increased and then decreased, reaching the highest at 6 minutes, and then significantly decreased after 6 minutes (P<0.05), L^* and b^* values increased, while a^* value decreased, and the color differences were significant between 6 and 8 minutes (P<0.05). Through a comprehensive analysis of the overall impact of heat treatment methods and time on various quality indicators of krill, it was concluded that microwave heating was preferred within 2 to 6 minutes, followed by high-pressure steaming; both microwave heating and high-pressure steaming were optimal within 6 to 8 minutes; and microwave heating and atmospheric pressure steaming performed better at 8 minutes or more. This study provides a theoretical basis for the processing of Antarctic krill, which is helpful for optimizing the processing flow, improving product quality, and promoting industrial development.

This study employed response surface methodology to optimize the preparation process of phosphorylated chicory polysaccharide iron. It characterized the structure of the composite using Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Through simulated artificial gastrointestinal fluid digestion experiments, sucrase hydrolysis experiments, and mucin-binding capacity assays, the in vitro digestive characteristics of phosphorylated chicory polysaccharide iron were systematically analyzed. The results indicated that the optimal reaction conditions were a reaction time of 1.1 h, a reaction temperature of 64 ℃, and a pH of 10. Under these conditions, the iron content of the prepared phosphorylated chicory polysaccharide iron reached 26.97%±0.25%. Infrared spectroscopy of phosphorized chicory polysaccharide iron showed that the O-H and C=O groups in the phosphorized chicory polysaccharide coordinate with Fe³⁺. XPS confirmed that iron was introduced into the phosphorized polysaccharide in the trivalent state (Fe³⁺). SEM observation revealed that the composite morphology was a dense layered structure. In vitro gastrointestinal digestion results showed that the iron retention rate in gastric fluid was >97% after 24 hours, while in the simulated intestinal environment containing mucin and sucrase, 59% was released after 7 hours, with a cumulative release rate of 74.5%±0.5% after 24 hours. This study provides a theoretical basis for the high-value utilization of chicory polysaccharide resources and the development of polysaccharide iron supplements.

Tomato grey mould, caused by Botrytis cinerea, is a severely damaging global disease. This study isolated a strain of antagonistic bacteria with strong inhibitory effects against the important plant pathogen Botrytis cinerea from healthy branches and leaves of Camellia sinensis in Yunnan's Gaoligong Mountain. The morphological and molecular biological identification results indicated that the antagonistic strain was Bacillus subtilis, which was designated as DB2203A. The fermentation conditions of strain DB2203A were optimized through single-factor and orthogonal experiments, and the antibacterial activity of the fermentation broth was determined along with a preliminary exploration of the antibacterial substances under these conditions. This study isolated and screened seven strains with strong antagonistic effects against pathogenic fungi from leaf and branch tissues. Among them, strain DB2203A exhibited the most significant inhibitory effect against B. cinerea, with its sterile fermentation broth achieving an inhibition rate of 74.77% against the pathogen. The optimal medium for the strain DB2203A was LB medium, with the best fermentation conditions being an inoculation volume of 6%, a filling volume of 50%, an initial pH of 7.0, and a fermentation time of 72 h. The research results also showed that the antifungal activity of the 40 times diluted fermentation broth against B. cinerea was 59.25%. Moreover, the lipopeptide substances in the fermentation broth could inhibit the growth of the mycelium of B. cinerea. The strain B. subtilis DB2203A and its lipopeptide metabolites exhibit promising potential for the green control of tomato gray mold, providing a theoretical foundation and microbial resources for the development of microbial products.

In order to investigate the effects of pre-harvest salicylic acid (SA) spraying on post-harvest quality and antioxidant metabolism of prunes (Prunus domestica L.), 'French' prune trees in Xinjiang were treated with SA solutions at concentrations of 1, 2, or 4 mmol/L. Applications were made during four key developmental stages: fruit set, expansion, color change, and maturity. A control group received water sprays. Following harvest, fruit were stored at 1.0±1.0 ℃ and 90%~95% relative humidity. Quality parameters and antioxidant metabolism indicators were assessed at 15 days intervals over the 90 days storage period. Results demonstrated that pre-harvest spraying of SA could significantly maintain the hardness, soluble solids content and titratable acid level of plum fruits during post-harvest storage, and inhibit the color blackening, respiration and weight loss rate of fruits. The 2 mmol/L SA treatment proved most effective. At the end of storage, the activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX), and glutathione reductase (GR) in the 2 mmol/L SA-treated prunes were 1.17, 1.40, 1.54, 1.23, and 1.26 fold those of the control group, respectively (P<0.05). The contents of ascorbic acid (AsA) and glutathione (GSH) were 2.70 and 1.08 fold those of the control group, enhancing the antioxidant enzyme activities and effectively maintaining AsA and GSH levels. Additionally, the production rate of superoxide anion (O₂⁻·), hydrogen peroxide (H₂O₂), and malondialdehyde (MDA) accumulation, as well as cell membrane permeability, were suppressed. This indicated that spraying SA before harvest could maintain the post-harvest quality of prunes by enhancing their antioxidant metabolism capacity.

Sweet cherries are susceptible to quality deterioration during postharvest storage and transportation, including flesh softening and spoilage, which greatly reduce their commercial value. In order to preserve postharvest quality and extend the shelf life of the fruit, this study utilized 'Samituo' sweet cherries as the experimental material to investigate the effects of pre-harvest spraying with alginate oligosaccharides at concentrations of 50, 100, and 200 mg/L on fruit quality-related parameters and the activities of cell wall degrading enzymes during low-temperature storage. The results indicated that the pre-harvest application of alginate oligosaccharides at various concentrations effectively delayed the decline in soluble solids content, titratable acidity, and fruit firmness, while also reducing the rate of fruit weight loss, as compared to the control group. Treatment with alginate oligosaccharides delayed the decline of L^*, a^*, and b^* values and color saturation, while also inhibiting the activities of pectate lyase, pectin methylesterase, polygalacturonase, cellulase, β-galactosidase, β-glucosidase, pectin methylesterase and polygalacturonic acid transeliminase. Among the treatments, 200 mg/L alginate oligosaccharides exhibited the most pronounced effect. The correlation analysis reveals that titratable acidity was significantly and positively correlated with the activities of β-galactosidase and pectin methylesterase, while was distinctly negatively correlated with the activities of polygalacturonase and cellulase. In contrast, soluble solids content exhibited a significant negative correlation with polygalacturonase, cellulase, polygalacturonic acid transeliminase, pectate lyase, and β-galactosidase activities. Furthermore, fruit hardness showed a significant negative correlation with the activities of polygalacturonase, cellulase, pectate lyase, and β-glucosidase. Weight loss was significantly positively correlated with polygalacturonase and cellulase activities, whereas it was significantly negatively correlated with the activities of polygalacturonic acid transeliminase, pectin methylesterase, pectate lyase, β-glucosidase, β-galactosidase, and pectin methylesterase. These findings suggest that pre-harvest application of alginate oligosaccharides can delay fruit softening and maintain storage quality by suppressing the activity of enzymes related to fruit cell wall degradation.

This study aimed to extract the active substance from Laminaria japonica (L. japonica) and evaluate their composition and hypolipidemic activity. The alcohol extract of L. japonica (LJA), water extract of L. japonica (LJW), enzymic hydrolysates of L. japonica (LJE) and dietary fiber extract of L. japonica (LJDF) were prepared by using different polar solvents combined with ultrasound-assisted alcohol extraction, water extraction, complex proteolytic enzymes and sodium carbonate acid, and their composition was analyzed. The above four active substances were mixed to obtain the total active substances of L. japonica (LJM). This study adopted C. elegans as a model organism to investigate the effects of bioactive compounds derived from L. japonica on lipid metabolism-related biochemical parameters and Messenger RNA (mRNA) transcription levels. The result revealed that the main components of LJA included choline, phospholipids, pyrimidines, terpenoids, arachidonic acid, steroids, polyphenols and disaccharides; LJW mainly consisted of two polysaccharides with molecular weights of 368.0 kDa and 1.0 kDa, with monosaccharide composition of glucose, galactose, fucose, mannose and arabinose; LJE mainly consisted of protein active peptides, containing six proteins (YP_006639117.1, AIW62928.1, WDS74817.1, WDS74887.1, QBF51285.1 and ABB80121.1), 43 peptides; LJDF mainly consisted of two polysaccharides with molecular weights of 717.073 kDa and 11.502 kDa, with monosaccharide composition of mannose aldehyde, gulonose aldehyde, galactose and fucose. The result of C. elegans experiments demonstrated that the L. japonica active substances significantly reduced triglyceride (TG) and malondialdehyde (MDA) levels (P<0.01). Meanwhile, these substances also increased total superoxide dismutase (T-SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) levels (P<0.01). At the mRNA transcription level, the L. japonica active substances significantly upregulated genes NHR-49, FAT-5, FAT-6, FAT-7, DAF-2, and DAF-16 (P<0.01). Conversely, the substances significantly downregulated genes MOD-1, ACS-2, and AGE-1 (P<0.01). This suggested that the L. japonica active substances improved C. elegans lipid peroxidation and reducing lipid accumulation in C. elegans through regulating fatty acid β-oxidation (NHR-49, MOD-1 and ACS-2), fatty acid synthesis (FAT-5, FAT-6 and FAT-7) and insulin (DAF-2, AGE-1, DAF-16) signaling pathways.