Abstract:The ability of a combination of enzymatic fragments of Porphyra polysaccharides of different molecular weights and oyster peptides to synergistically reduce exercise fatigue was investigated. Mice were randomly divided into a normal group (N), an exercise group (M), an oyster peptide intervention group (O), and combined intervention groups jointly treated with oyster peptides and high-, medium-, and low-molecular-weight enzymatic fragments of Porphyra polysaccharides (OH, OM, and OL). All groups received continuous intervention for 16 d. Compared with oyster peptide intervention alone, interventions combining enzymatic fragments of Porphyra polysaccharides and oyster peptides yielded superior anti-fatigue activity. In the OH, OM, and OL groups, swimming endurance times increased by 60.77%, 37.25%, and 37.59%, respectively. In the OH group, liver AST and ALT levels decreased by 12.88% and 11.39%, respectively. Serum CK and LDH activities were significantly reduced by 22.02% and 8.99%, respectively, suggesting that exercise-induced liver and skeletal muscle damage was reduced. Liver glycogen content also increased in the intervention groups, whereas serum lactate and urea nitrogen levels decreased, indicating reduced oxidative stress levels. Mechanism analysis revealed that a combination of enzymatic fragments of Porphyra polysaccharides with oyster peptides synergistically upregulated PGC1α/TFAM signaling in skeletal muscle, increased the abundance of beneficial Lactococcus bacteria, and decreased the abundance of pathogenic bacteria, including Staphylococcus, Acinetobacter, Oscillospira, and Ruminococcus. In conclusion, a combination of enzymatic fragments of Porphyra polysaccharides with oyster peptides can synergistically ameliorate exercise fatigue in mice by promoting mitochondrial biogenesis and regulating gut microbiota. High-molecular weight enzymatic fragments of Porphyra polysaccharides (Mw=267.3 ku) exhibited the best efficacy. This study provides a theoretical basis for the development of Porphyra-based health products.

Abstract:The Aβ1-42 zebrafish model, established via intracerebroventricular microinjection, was employed to investigate the ameliorative effects of Pseudostellaria heterophylla fractionated polysaccharides (PF30, PF60, PF90) on Alzheimer's disease (AD)-associated cognitive deficits, as well as the underlying mechanisms and the primary active constituents responsible for these effects. The total sugar, protein content and molecular weight of PF30, PF60 and PF90 were determined by phenol-sulfuric acid method, Coomassie brilliant blue method and gel chromatography, respectively. UV and FT-IR spectroscopy were sued for characterization. Novel object recognition, reward T-maze behavior experiments were performed to explore the effects of PF30, PF60, and PF90 on cognitive impairment in the AD zebrafish model. Fluorescence quantitative PCR was used to determine the expression levels of related mRNAs in the zebrafish brain. The results revealed that the mass fractions of total sugar contents of PF30, PF60 and PF90 were 70.54%, 69.00% and 80.19%, respectively; the mass fractions of protein contents were 2.51%, 5.08% and 1.89%, respectively; the molecular weights (Mw) were 23.1, 8.97 and 1.72 ku, respectively. The comparison of the results of zebrafish experiments revealed that PF30 significantly increased the retention time of zebrafish in the new arm and the reward arm, increased the number of times the zebrafish entered the new arm and the reward arm, alleviated the brain neuroinflammation, significantly inhibited the expression of CDK5 and GSK-3β, and ameliorated the cognitive memory impairment in zebrafish. Therefore, PF30 showed the greatest ameliorating effect on cognitive impairment in zebrafish among the three graded polysaccharides of Pseudostellaria heterophylla.

Abstract:In this study, Abalone Visceral Phospholipids (AVP) was used as the research object to study its hypolipidemic effect on high-fat diet mice. The components, fatty acid composition and physicochemical properties of AVP were analyzed. The results showed that AVP was composed of phosphatidylcholine, phosphatidylethanolamine and phosphatidylinositol, with their contents being 80.69%, 3.66% and 5.06%, respectively. There were five saturated fatty acids and nine unsaturated fatty acids (content: 15.97%). AVP was brownish-yellow particles with a phospholipid smell, acetoneinsoluble matter cntent as 88.3%, content of water and volatiles as 0.8%, n-hexane insoluble matter content as 0.1%, acid value as 34.4 mg KOH/g, and peroxide value as 9.45 mmol/kg, all of which met the national standards. Animal experiments were carried out to verify the auxiliary hypolipidemic effect of AVP on mice fed a high-fat diet. The results showed that compared with the high-fat diet group, the serum TG, TC, and LDL levels in the high-dose AVP group decreased by 47.63%, 32.02%, and 44.73%, respectively, the serum HDL increased by 30.78%, and the AI index decreased by 64.85%. In summary, AVP plays a certain role in assisting the reduction of hyperlipidemia, which provides a theoretical basis for the subsequent development and utilization of abalone viscera resources.

Abstract:Five-year-old cultivated ginseng was processed into ginseng products through direct extraction, microbial fermentation, and enzymatic hydrolysis. The antioxidant effects of these ginseng products were investigated and compared by measuring their in vitro antioxidant activities and cytoprotective effects. The results showed that all ginseng products prepared using the three methods of interest could scavenge free radicals, and the highest DPPH, ABTS+, and hydroxyl radical scavenging rates were 97.80%, 93.70%, and 99.46%, respectively. The cell survival rate of HepG2 cells was 52.68% after inducing damage with 600 μmol/L H2O2 for 2 h, which satisfied the modeling requirements. The highest cell survival rates (exceeding 95%) were observed when the cells were treated with 200 mg/L ginseng products, regardless of the production method. All three ginseng products could significantly increase the survival rate of damaged HepG2 cells (P<0.01), reduce the levels of nitric oxide (NO) and malondialdehyde (MDA), and increase the activity of intracellular superoxide dismutase (SOD) and the content of glutathione peroxidase (GSH). In particular, the ginseng products obtained through enzymatic hydrolysis demonstrated the most significant effects, with a cell survival rate of 98.10%. In vitro antioxidant activity and cell experiments demonstrated that ginseng extracts, fermentation products, and hydrolysates prepared using different methods all have apparent antioxidant effects. Among them, ginseng hydrolysates exhibited the most remarkable effects. This study provides a reference for the development of antioxidant ginseng products.

Abstract:The effects of using mixed peptides (fish collagen peptides and mussel peptides) and mixed polysaccharides (Dendrobium officinale polysaccharides and Morinda officinalis polysaccharides) alone and in combination on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) were compared. UC was induced in C57/BL6 mice by allowing them to drink 3% DSS solution ad libitum for 7 days. A total of 40 mice were randomly divided into five groups: normal group, model group, peptide-treated group, polysaccharide-treated group, and combined intervention group. Combined intervention yielded the best ameliorative effect among the three types of intervention. Compared with the model group, the combined intervention group showed an 8.93% increase in body weight change rate and a 57.14% decrease in disease activity index (DAI) score. In mice in the combined intervention group, the length of the colon increased by 29.64%, while splenomegaly and hepatomegaly were reduced by 26.19% and 20.39%, respectively. The pathological score was decreased by 55.43%, and the levels of the serum inflammatory factors interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) decreased by 24.39%, 20.69%, and 26.53%, respectively. Relative expression levels of tight junction proteins ZO-1, occludin, and claudin 1 increased by 132.61%, 79.49%, and 112.77%, respectively. All noted differences were found to be statistically significant (P<0.05). Overall, the combined use of polysaccharides and polypeptides can ameliorate DSS-induced UC in mice and prevent further deterioration due to UC. These findings provide insights into the development of health products to treat UC.

Abstract:Intestinal flora is a key factor influencing human health, and dietary fibers play an important role in regulating the balance of intestinal flora. In this study, based on the in vitro digestion experiment of Qingyi brand resistant dextrin, the effects of resistant dextrin on the in vitro growth of Lactobacillus bulgaricus and Lactobacillus casei were investigated, and the differences between resistant dextrin and other dietary fibers in the in vitro proliferation of the two kinds of probiotics were compared and studied. The results showed that the maximum degrees of hydrolysis of Qingyi brand resistant dextrin in simulated gastric and intestinal fluids were 1.32% and 3.67%, respectively, indicating that the product possessed good gastrointestinal digestion-resistant properties. Although the resistant dextrin could not be used as a sole nutrient carbon source to promote the proliferation of two probiotics, but under the condition of ensuring nutrient source, the addition of a certain amount of resistant dextrin to basal nutrient medium could promote the in vitro growth of the strains, and the better amounts for addition to the basal media were 0.6% and 0.4% (m/m) for Lactobacillus bulgaricus and Lactobacillus casei, respectively. Moreover, compared with the addition of other dietary fibers, such as polydextrose, inulin and fructooligofructose, resistant dextrin enabled a greater extent of proliferation of two probiotics, with the OD600 values at the stable phase reaching 2.0, indicating that the utilization rate of resistant dextrin was greater. The results of this study provide a theoretical support for the effective regulation of intestinal flora by water-soluble resistant dextrin.

Abstract:The antioxidant capacity of Amomum tsao-ko (A. tsao-ko) lipids and their effects on diabetes in mice induced by intraperitoneal injection of alloxan (ALX) (200 mg/kg) were investigated to provide support for both blood glucose reduction and organ damage prevention in diabetes. The antioxidant capacity of A. tsao-ko lipids was evaluated by measuring the scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) ammonium salt (ABTS+) free radicals. Diabetic mice were fed a standard diet supplemented with (ALX+A. tsao-ko group) and without (ALX model group) A. tsao-ko lipids (500 mg/kg) for 28 days, and their body weight, blood glucose levels, and blood lipid parameters were measured. The results showed that A. tsao-ko lipids exhibit ABTS+ and DPPH scavenging rates of 97.21% and 98.13%, respectively, at a concentration of 16 μg/mL. The weight loss in the ALX+A. tsao-ko group was not significant (P>0.05), but a decreasing trend in the blood glucose level was observed from 0 d to 7 d (P<0.05). The high-density lipoprotein (HDL) content in blood lipids in the ALX+A. tsao-ko group increased significantly (P<0.05), while the low-density lipoprotein (LDL) content decreased significantly (P<0.05) at the end of the feeding period (28 d). In conclusion, A. tsao-ko lipids have strong antioxidant activity and can effectively control weight loss in diabetic mice to reduce blood sugar, regulate blood lipids, alleviate organ damage, and support liver metabolism. Therefore, A. tsao-ko lipids can be developed and utilized as a hypoglycemic agent for diabetes and to control its deterioration.

Abstract:The effects of different capsaicin doses on gastrointestinal inflammation and the gut microbiota structure in Escherichia coli O157:H7-infected mice were investigated. A mouse model of E. coli O157:H7 infection was established, and successfully infected mice were randomly divided into control, infected, and capsaicin-treated groups, receiving 15, 7.5, and 3.75 mg/kg capsaicin treatment, respectively, for seven days. The food intake and body weight were recorded. Levels of inflammatory factors, including tumor necrosis factor-α and interleukin-6 in the serum, and the inflammatory marker myeloperoxidase in the intestinal tissue, were determined. Histopathological changes in the colon and gastric tissues were observed. Additionally, changes in the mouse gut microbiota were identified through 16S rDNA sequencing. The results revealed that administration of 15 mg/kg capsaicin substantially reduced the levels of inflammatory factors in the serum and intestinal tissue of E. coli O157:H7-infected mice, improved gastrointestinal barrier damage and inflammation, and increased the abundance of Akkermansia, Anaeroplasma, and Cetobacterium. The relative abundance of Akkermansia increased by 48% compared to that in the control group. In contrast, capsaicin intake substantially reduced the abundance of Alistipes, Enterococcus, and Yokenella. In conclusion, dietary intake of 15 mg/kg capsaicin can improve gastrointestinal inflammation and the gut microbiota structure in mice infected with E. coli O157:H7. These findings provide insights for treatment interventions and dietary strategies for mice with E. coli O157:H7 infection.

Abstract:The effects of aqueous extract of Elsholtzia rugulosa Hemsl. on lipid deposition in high-fat diet-fed mice were studied. C57BL/6J mice were randomly divided into four groups (n=6 each): control (CK), high-fat diet (HFD), metformin hydrochloride (POS) intervention, and aqueous Elsholtzia rugulosa Hemsl. (HFD+Y) intervention. Except for the control group, which received a normal diet, all other groups were fed a high-fat diet for 16 weeks. The mice's body weight, fasting blood glucose, food intake, and water consumption were recorded weekly. Intraperitoneal glucose tolerance test (IPGTT) and intraperitoneal insulin tolerance test (IPITT) were conducted at weeks 14 and 15. At the end of the feeding period, organ indices and serum biochemical parameters were measured, and morphological changes in liver cells and adipocytes were observed. The results showed that aqueous Elsholtzia rugulosa Hemsl. extract could reduce body weight gain and fat accumulation in the body, leading to decreases in inguinal fat by 34.59% and epididymal fat by 45.21%. The aqueous extract improved glucose tolerance and insulin sensitivity while reducing serum triglyceride (15.54%), total cholesterol (24.69%), and alanine aminotransferase (40.78%) levels and hepatic triglyceride (36.14%) and total cholesterol (24.89%) contents. In conclusion, aqueous Elsholtzia rugulosa Hemsl. extract resulted in body weight gain, enhanced insulin sensitivity, and reduced lipid deposition in mice fed a high-fat diet. This study provides a theoretical basis for developing natural compounds to treat lipid metabolism disorders.

Abstract:Cathepsin D plays a potential role in the degradation of muscle proteins, thereby influencing their functional properties and structural integrity. The changes in functional properties and microstructure of muscle proteins in Parapenaeopsis hardwickii treated with cathepsin D were investigated through in vitro simulation. Myofibrillar, actin, and sarcoplasmic proteins were extracted from P. hardwickii muscles and were divided into the experimental (treated with cathepsin D) and control (which received no enzyme treatment) groups. All samples were incubated at 50 ℃ for 30 min. The turbidity, surface hydrophobicity, endogenous fluorescence, free amino acid content, and particle size were measured. Compared with the control groups, the experimental groups exhibited significantly higher turbidity and surface hydrophobicity (P<0.05) but lower endogenous fluorescence, free amino acid content, and particle size. Turbidity values of the three proteins in the experimental groups were 0.45, 0.45, and 0.42, respectively. The amounts of bound bromophenol blue were 9.66, 56.30, and 2.34 μg, respectively, exceeding those noted in the control groups. Furthermore, the particle sizes of the three proteins in the experimental groups were 819.8, 3 230.3, and 1 459.8 nm smaller than those of the control groups. The levels of antioxidant amino acids (such as glycine and alanine) in the three protein types within the experimental groups were also significantly lower than those in the control group. These results indicate that cathepsin D effectively degrades myofibrillar, actin, and sarcoplasmic proteins in the muscles of P. hardwickii, thereby disrupting their functional properties and promoting muscle softening and autolysis. These findings provide a theoretical basis for in vitro simulation of cathepsin D and storage quality control of P. hardwickii.

Abstract:A hypervirulent persistent genotype (HVPG) Yersinia enterocolitica strain Y2844 was selected as the host for the isolation of a novel lytic Y. enterocolitica bacteriophage, vB_YenP_WW1 (WW1), from sewage samples collected from Guangzhou, China. Genome sequencing revealed that phage WW1 possesses a complete genome of 39,589 bp and shares the highest nucleotide sequence similarity (92.77%) with Escherichia phage P483. Phage WW1 exhibited tolerance to a broad range of temperatures (4~50 ℃) and pH values (5~11). Bactericidal assays revealed that WW1 effectively inhibited Y. enterocolitica growth in LB broth at 28 ℃ for up to 8 h. Following 24 h of phage treatment at 4 ℃, WW1 reduced viable Y. enterocolitica counts on raw pork surfaces from 3.82 log CFU/mL to 2.67 log CFU/mL and decreased viable Y. enterocolitica counts in milk from 5.41 log CFU/mL to below the detection limit. Furthermore, phage WW1 significantly inhibited biofilm formation by Y. enterocolitica on polyethylene and stainless steel surfaces. These findings suggest that phage WW1 possesses strong environmental tolerance and considerable potential as an antimicrobial agent for controlling Y. enterocolitica contamination in food matrices and food processing factories.

Abstract:Four different extracts of cinnamon powder were prepared using the solvents water, anhydrous ethanol, petroleum ether, and ethyl acetate. A model of insulin resistance was established using 3T3-L1 preadipocytes to evaluate the hypoglycemic effects of different solvent extracts. Next, α-amylase and α-glucosidase inhibition assays were performed to track and isolate the hypoglycemic components in the extracts. Thereafter, these components were identified. CCK-8 cell viability results showed that all four solvent extracts exhibited low cytotoxicity toward 3T3-L1 cells at concentrations below 100 μg/mL. In addition, the ethyl acetate extract demonstrated good hypoglycemic activity at concentrations of 10, 20, and 50 μg/mL. In contrast, the ethyl acetate extract was less effective at α-glucosidase inhibition than the water extract, but displayed the highest α-amylase inhibitory activity. Based on these observations and our cell-based experiment results, the cinnamon extract in ethyl acetate was selected for further isolation. The F5 fraction obtained by silica gel column chromatography exhibited strong hypoglycemic effects, and the α-amylase and α-glucosidase inhibition rates were 66.08% and 98.21%, respectively. According to mass spectrometry analysis, the main constituents of the F5 fraction were transcinnamaldehyde and 4-methoxycinnamaldehyde, with relative molecular weights of 132.06 and 162.07, respectively. Transcinnamaldehyde and cinnamaldehyde exhibited specific hypoglycemic activities. These findings can serve as a valuable resource for further development and utilization of cinnamon as a hypoglycemic dietary supplement.

Abstract:To promote efficient utilization of chicken bones and development of novel antioxidants, antioxidant peptides were generated from chicken bone meal fermented with Bacillus licheniformis. First, the effect of glucose addition on Bacillus licheniformis growth was examined. Next, fermentation conditions were optimized using single-factor experiments and response surface methodology. Tricine-SDS-PAGE was simultaneously performed on the chicken bone fermentation broth. Finally, the chicken bone peptides in the fermentation broth were separated using an organic membrane, and their antioxidant activities were determined. The addition of glucose inhibited B. licheniformis growth. The optimal fermentation conditions were as follows: 4.2% (m/m) of chicken bone meal, initial pH of 6.0, 4.0% (v/v) of bacterial inoculum, working volume of 50 mL in a 250 mL flask, and fermentation time of 24 h. These conditions yielded 56.29% hydrolysis in the fermentation broth, and the DPPH• scavenging rate reached 57.11%. Tricine-SDS-PAGE results verified that the chicken bone meal was hydrolyzed. Among the antioxidant peptide fractions obtained by organic membrane separation, fraction V (with a molecular weight of 3~5 kDa) exhibited the highest antioxidant activity. Its respective DPPH, superoxide anion, and ABTS+ scavenging activities were 59.08%, >20.21%. and 85%, respectively. This study lays a foundation for increasing the overall utilization value of chicken bones and expands the scope of research and development of functional products.

Abstract:In this study, the biosynthesis pathway and regulatory mechanism of triterpenoids in Rosa roxburghii (R. roxburghii) were systematically investigated through combined use of liquid chromatography-mass spectrometry and transcriptome analysis. The results showed that there were significant differences in triterpenoid content between cultivated and wild R. roxburghii varieties, with the cultivated variety exhibiting an approximately 30 wt.% higher triterpenoid content compared with the wild variety. Such a difference remained constant in the different growth stages of R roxburghii. Through high-throughput transcriptome sequencing technology, five key genes associated closely with the biosynthesis of triterpenoid were successfully identified in this research. These genes had high homology to genes such as CYP716A1, CPY734A1, CPY72A15, UGT74F2, and UGT85A2, suggesting their key roles in the synthesis of triterpenoid in R. roxburghii. In this study, the combined metabolomic and transcriptome analysis not only clarified the differences in the triterpenoid content of R. roxburghii and also successfully identified the key genes participating in the biosynthesis of triterpenoids, which offers fresh insights and potential molecular markers for the quality improvement and molecular breeding of R. roxburghii.

Abstract:The effects of a static magnetic field on germination and biological zinc enrichment of soybeans were investigated. The influences of static magnetic field strength (0, 15, 25, 35, and 45 mT) and treatment time (0.5, 1, 1.5, 2.5, and 3.5 h) on the germination rate, seedling length, fresh weight, and soluble protein content of soybeans were initially assessed. Next, after different concentrations of exogenous zinc sulfate (0, 40, 80, 120, 160, and 200 mg/L) were applied during germination, the effects of a static magnetic field strength and time of application (initial, intermediate, and final stages of germination) on the germination and protein zinc content of soybeans were evaluated. The results showed optimal soybean germination under the following conditions: a static magnetic field strength of 35 mT and a treatment time of 0.5 h. The seedling length (23.54 mm) and soluble protein content (384.28 mg/g) were significantly increased by 15.70% and 19.81%, respectively, compared to those of the control group. However, no significant differences were observed in the germination rate and fresh weight between the groups (P>0.05). In addition, compared with those of the control group, the total zinc content (106.68 mg/kg) and protein zinc content (27.37 mg/kg) of soybeans germinated for 24 h increased by 8.64% and 26.68%, respectively, after exposure to a static magnetic field (field strength, 35 mT; time, 0.5 h; intervention period, anaphase) combined with exogenous zinc sulfate (120 mg/L). In conclusion, an optimal combination of a static magnetic field and exogenous inorganic zinc can promote the germination of soybeans and induce the accumulation of proteintype biological zinc in soybeans. These findings provide a novel technology for the development of natural zinc-rich food ingredients.

Abstract:The physicochemical properties of carrageenan/kudzu starch blends (CK) with varying carrageenan: kudzu starch ratios were investigated to improve the processing performance and edible quality of natural kudzu starch. The results revealed that the viscosity, retrogradation value, yield stress, loss modulus, and storage modulus of CK pastes decreased significantly and the pasting temperature rose significantly after carrageenan was added. Moreover, the CK gel showed a homogeneous porous structure, and the syneresis rate, relative crystallinity, hardness, gumminess, and chewiness decreased significantly, while the resilience increased significantly. At a 10:90 (m/m) ratio, peak viscosity, holding strength, breakdown value, final viscosity, and retrogradation of the blend decreased by 20.30%, 10.12%, 54.60%, 16.96%, and 28.18%, respectively, compared to natural kudzu starch. The pasting temperature increased by 4.00 ℃, and the yield stress, hardness, gumminess, and chewiness decreased by 9.03 Pa, 489.45 g, 422.37 g, and 413.58 g, respectively. The resilience increased by 0.14, while relative crystallinity reduced by 6.04%. In conclusion, carrageenan increased the pasting temperature of CK, enhanced the shear stability and fluidity of the paste, and decreased the viscoelasticity, making the gel texture softer. These findings provide a reference for the processing of kudzu starch products.

Abstract:A post-harvest preservation technology suitable for litchi was investigated and the effects on the low temperature storage quality of ‘Guiwei’ litchi were determined using individual pre-cooling methods and in combination with nano-cinnamaldehyde. The results indicated that litchi treated with iced water pre-cooling is prone to browning and rotting during cold storage, with a significantly higher susceptibility index and browning index than other treatments. The total soluble solids, titratable acid, and vitamin C contents of litchi treated with iced water pre-cooling decreased at a more rapid rate, and the activities of polyphenol oxidase and peroxidase peaked at 5.98 and 91.33 U/g, respectively, on the 8th day. Chilled air pre-cooling was more effective than other cooling methods in delaying pericarp browning and maintaining the nutritional value of litchi. The shelf life of litchi pre-cooled with cold air was extended by more than 6 days compared with iced water pre-cooled litchi. In addition, nano-cinnamaldehyde treatment significantly reduced the presence of diseased litchi pre-cooled with iced water and cold air, by 62.29% and 44.49%, respectively, on the 21st day, compared with iced-water precooling and chilled air pre-cooling, individually. This results indicates that nano-cinnamaldehyde is effective in inhibiting the presence of post-harvest diseases in litchi. Moreover, the browning of iced water pre-cooled litchi was reduced by nano-cinnamaldehyde treatment, resulting in a remarkably lower browning index (2.76 vs. 3.51) on the 15th day. In conclusion, chilled air pre-cooling is more suitable than other cooling methods for ‘Guiwei’ litchi and nano-cinnamaldehyde treatment is effective in inhibiting the presence of post-harvest diseases and improving the post-harvest quality of litchi.

Abstract:The effects of air frying with rapid air circulation on the quality of lightly pre-fried Zhoushan hairtail were studied. The oil content and sensory properties of hairtail after pre-frying at 160, 170, and 180 ℃ for 20, 40, and 60 s were determined. The results revealed that hairtail pre-fried at 170 ℃ for 20 s had a relatively low oil content (8.25%) and the highest sensory score. Following this step, pre-fried hairtail was air-fried at 190 ℃ for 12, 16, and 20 min, and the sensory properties, texture, color difference, moisture content, water activity, free amino acid content, and microstructure were determined. The moisture content and water activity decreased as air-frying time increased. The redness and yellowness values increased, and brightness decreased obviously. The content of free amino acids rose significantly (P<0.05). Hematoxylin and Eosin staining revealed that longer air frying times lead to larger gaps between muscle fibers, muscle fiber breakage, and a significant decline in muscle fiber integrity. The highest sensory scores were obtained at 16 min of air frying. The hairtail had a golden color, good elasticity (0.68 mm) and hardness (791.67 g), and intact and compact muscle fibers. In conclusion, based on the above findings and the sensory evaluation results, pre-frying hairtail at 170 ℃ for 20 s followed by air frying at 190 ℃ for 16 min is recommended. This study can provide insights into different heat treatment methods for hairtail.

Abstract:Zanthoxylum schinifolium Sieb. et Zucc. is a spice and medicinal plant with major regional variations due to differences in environmental conditions. This study aims to assess the overall quality of Z. schinifolium harvested from 15 regions within the same year by measuring color, aroma, flavor, and bioactive compounds. Principal component analysis, partial least squares discriminant analysis, and an entropy weight evaluation model were used to assess the variations. Significant quality differences (P<0.05) were observed among samples from different regions. These variations are primarily attributed to differences in the contents of chlorophyll a, chlorophyll b, and hydroxy-α-sanshool, as well as the browning index and browning degree, with the corresponding degrees of contribution determined to be 2.11, 1.77, 1.60, and 1.31, respectively. Samples from Yunnan, Guizhou, and Sichuan provinces and Chongqing exhibited a more pleasant sensory color and higher concentrations of chlorophyll a (220.02~543.94 μg/g DW), chlorophyll b (123.88~276.54 μg/g DW), volatile oil (2.80~6.25 mL/100 g DW), alkylamides (45.42~81.54 mg/g) DW), total phenols (28.68~43.56 mg GAE/g DW), and total flavonoids (59.26~114.58 mg RE/g DW). Samples from Hanyuan, Luxian, and Jiangjin had the highest overall evaluation scores, reaching 242.06, 202.46, and 179.23, respectively. Due to their superior quality, Z. schinifolium Sieb. et Zucc. from these three regions may be considered ideal ingredients for cooking, seasoning, and functional food development.

Abstract:Pickering emulsions are stabilized by solid particles that act as emulsifiers and are irreversibly adsorbed at the oil-water interface. The low solubility of flavonoids in water provides a theoretical basis for their use as stabilizers in Pickering emulsions. In this study, luteolin, a natural flavonoid, was combined with two polysaccharides, i.e., carboxymethyl chitosan and hyaluronic acid, to form composite particles, which were subsequently used as emulsifiers to obtain antioxidant and stable food-grade Pickering emulsions. The results showed that luteolin could effectively increase the emulsification effect of polysaccharides. The prepared emulsions exhibited a uniform droplet size, with an average size of approximately 660.23 nm, and the droplets were well dispersed with a PDI of approximately 0.10. The emulsions were still stable even under changing environmental conditions and could maintain good physical stability after 15 days of storage. The accelerated oxidation results showed that the primary oxidation products (peroxide value, POV) of the emulsions were significantly reduced during the storage process after the addition of luteolin. Hence, adding luteolin enhanced the oxidative stability of the emulsions. Therefore, by synergizing luteolin with hyaluronic acid-carboxymethyl chitosan to give composite particles and applying them as emulsifiers, luteolin was shown to significantly improve the emulsion stability, delay lipid oxidation while acting as an active ingredient. These findings provide a theoretical basis for using flavonoids in stabilizing Pickering emulsions, which is conducive to the efficient utilization of flavonoids.

Abstract:In the study, taking commercially available pasteurized milk and milk powder from cows, sheep and camels as the research object, the classification and mass fraction of fatty acids (FA) in different types of milk were analyzed by gas chromatography-area normalization method, so as to carry out the differentiation study of different milks with fatty acids as characteristic factors. The result showed that myristic acid (C14:0), palmitic acid (C16:0), stearic acid (C18:0) and oleic acid (C18:1n9c) were the main fatty acid components in goat, bovine and camel milks. The sum of the mass fractions of the above four fatty acids was greater than 70%. The mass fractions of palmitenic acid (C16:1) and stearic acid (C18:0) in camel milk were significantly higher than those in cow milk and goat milk. The mass fractions of palmitic acid (C16:0) and butyric acid (C4:0) in the bovine milk were significantly higher than those of goat and camel milks. The mass fractions of caprylic acid (C8:0) and capric acid (C10:0) in goat milk were significantly higher than those in the bovine milk. A total of 36 fatty acids, 35 fatty acids and 33 fatty acids were detected in camel milk, goat milk and bovine milk, respectively. The principal component analysis revealed that there existed significant differences in the compositions and contents of fatty acids in different milks, and the composition and contents of fatty acids can be used for distinguishing goat milk, camel milk and bovine milk.

Abstract:Starch retrogradation is the main contributor to quality deterioration of chilled rice during storage. To clarify the influence of fructooligosaccharides on the quality of chilled rice, the effects of adding different mass fractions (1%, 2%, 3%, and 4%) of fructooligosaccharide on water absorption by soaking rice, and fraction-dependent effects on the texture, taste value, and iodine blue value of rice after cooking were studied. Rice microscopic morphology was observed through scanning electron microscopy. Differential scanning calorimetry, Fourier transform-infrared spectroscopy (FT-IR), and X-ray diffraction were employed to analyze the mechanism by which fructooligosaccharides influence rice retrogradation. After soaking in 1% (m/m) fructooligosaccharides for 15 min, the water absorption rate of rice reached 17.60%, representing a significant increase of 11.69% compared with that of the control group (P<0.05). After storage for 7 days, the hardness of rice treated with 1% fructooligosaccharides significantly reduced by 13.17% compared with that of the control group. Taste was best preserved with 1% fructooligosaccharide treatment. Compared with those of the control group, the enthalpy of regeneration and relative crystallinity of the 1% fructooligosaccharide treatment group were lower. The FT-IR ratio of 1 047/1 022 cm-1 in the infrared spectrum decreased from 1.07 to 1.02. The treated rice exhibited a more compact and dense microstructure and improved retrogradation resistance compared with the control rice. In short, fructooligosaccharides maintained the quality of chilled rice and inhibited starch recrystallization. This study provides data supporting the application of fructooligosaccharides in delaying the retrogradation of starch-based products.