Abstract:The nutritional and functional components in human breast milk play a crucial role in the healthy growth and development of infants. As the research on human breast milk deepens, more and more functional components are extracted and added into infant formula. The author reviewed the functional proteins, functional lipids, oligosaccharides, and probiotics of human breast milk in terms of their types, content, and effects on infant health. Furthermore, the preparation and application of core ingredients of infant formula were summarized. This review has guiding significance for solving the bottleneck problems in the production of core ingredients for infant formula and achieving the healthy development of China's infant formula industry.

Abstract:Lysozyme, a natural antibacterial enzyme widely existing in nature, can selectively hydrolyze the bacterial cell wall to make it inactive. Lysozyme could be used as a safe food preservative in the food industry. Lysozyme was introduced from physicochemical properties, antibacterial mechanism, and influences of various factors on the antibacterial activity. The application progress of lysozyme in the fresh-keeping and storage of various food products, as well as the application progress of lysozyme in combination with high-pressure ultrasonic treatment, controlled release packaging, and air-conditioned packaging, was reviewed, which provided a basis for the development of new, green, and safe preservatives.

Abstract:Food safety issues arising from foodborne bacteria are becoming increasingly severe, and the overuse of conventional antimicrobials exacerbates the emergence of drug-resistant bacteria, thereby posing a serious threat to public health. Given the specificity and safety profile, bacteriophage therapy serves as a novel bio-antimicrobial agent for foodborne drug resistant bacteria, demonstrating a promising prospect. However, the narrow antimicrobial spectrum of bacteriophages limits their application. To address this limitation, a synergistic approach that combines bacteriophage therapy with other antimicrobials is being explored. By integrating the specificity of bacteriophages with the broad-spectrum efficacy of antimicrobials, it is possible to effectively overcome the constraints associated with single-agent treatments while also reducing the dosage required for these agents. This strategy can achieve a more efficient and environmentally friendly antimicrobial effect. The recent advancements in research concerning interactions of bacteriophages with antibiotics, essential oils, organic acids, nanoparticles, and antimicrobial peptides for controlling antimicrobial resistance in foodborne bacteria were reviewed. Furthermore, the future trends in development and potential applications of phage-antimicrobial interactions were anticipated, with an aim of providing a reference for further solving the problem of foodborne drug-resistant bacteria and improving antimicrobial efficacy.

Abstract:[Objective] The aim of the study is to investigate the effect of Pueraria thomsonii Benth combined with Lactiplantibacillus plantarum Ali. Plateau. Lp. Ⅷ (APLp. Ⅷ) on acute alcoholic liver injury in mice. [Method] A mouse model of acute alcoholic liver injury was established and treated by APLp. Ⅷ and/or Pueraria thomsonii Benth. The therapeutic effect on acute alcoholic liver injury was compared between the group with APLp. Ⅷ or Pueraria thomsonii Benth and the combination group. [Result] The mice in the combination group showed prolonged clinging and climbing time and an increased distance in the center in the open field test, which indicated that the combination enhanced the motor coordination and spatial exploration abilities of mice. Additionally, the blood of mice in the combination group showed a significant reduction in ethanol mass concentration and a significant increase in the activity of aldehyde dehydrogenase (ALDH). Furthermore, the combination group had significantly weakened activities of alanine aminotransferase (AST) and aspartate aminotransferase (ALT), a declined level of malondiadehyde (MDA), increased activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and enhanced total antioxidant capacity (T-AOC). Histopathological sections of the liver tissue showed significant alleviation of the injury in the combination group. [Conclusion] APLp. Ⅷ combined with Pueraria thomsonii Benth has synergistic effects in preventing alcoholic liver injury in mice.

Abstract:[Objective] To investigate the preventive effect of natural selenium-enriched black soybean protein (SeBSP, selenium mass fraction is 84.00 mg/kg) on the liver injury induced by benzo[a]pyrene (BaP), a harmful product of high-temperature processed food, in BALB/c mice. [Method] This study used normal black bean protein (BSP, selenium mass fraction is 0 mg/kg) as a control. Both SeBSP and BSP, were characterized and used to feed BaP exposed mice by gavage. After 30 d of gavage, the liver tissues of mice were observed histopathologically, and the levels of serum liver function indicators, liver oxidative indicators, BaP metabolism-related indicators and pyroptosis-related inflammatory factors were detected. [Result] Both SeBSP and BSP prevented the liver injury caused by BaP, improved lipid metabolism, reduced the levels of MDA and H₂O₂, and increased the levels of GSH-Px and T-SOD in mice. SeBSP outperformed BSP in inhibiting the formation of the final carcinogen BPDE-DNA by effectively reducing the activity of BaP metabolism-related enzyme AhR and the relative mRNA levels of CYP1A1, CYP1B1 and GSTP1, thus attenuating the hepatotoxicity of BaP. Moreover, SeBSP significantly down-regulated the relative mRNA levels of NLRP3, ASC, Caspase-1, GSDMD and inflammatory factors (TNF-α, IL-1β, IL-18, iNOS and COX-2), thereby ameliorating the BaP-induced pyroptotic injury in the liver. [Conclusion] The results revealed that SeBSP could effectively prevent BaP-induced liver injury by inhibiting BaP-induced oxidative damage to the liver, regulating BaP metabolism-related enzymes and reducing pyroptosis. The findings provide a basis for controlling the hepatotoxicity of BaP and expanding the functions of selenium resources.

Abstract:[Objective] The purpose of this study is to study the antithrombotic effect and composition of peach kernels and provide a theoretical basis for preventing thrombogenesis by peach kernels. [Method] The active components of peach kernels were extracted by ethanol at a volume fraction of 70% and deionized water and separated by multiple chromatography techniques. The antithrombotic components were screened by a rat model of arteriovenous bypass thrombosis and in vitro anti-platelet aggregation test combined with molecular docking. The chemical structures were identified by nuclear magnetic resonance (NMR) spectroscopy. [Result] The 10% ethanol elute of peach kernel water extract separated by MCI column chromatography significantly reduced the thrombus mass in rats (P<0.05). The subsequent separation with ODS column chromatography led to the isolation of five monomer compounds, including mandelate-β-D-glucopyranoside (compound 1), 1-β-D-glucoside phenylidene-2-β-D-glucoside (compound 2), 3-(3-indolyl) butyric acid (compound 3), α-hydroxypropionic acid (compound 4), and dl-mandelic acid (compound 5). Compounds 1, 2, and 5 exhibited inhibitory effects on adenosine diphosphate (ADP)-induced platelet aggregation in vitro (P<0.05). Among them, compound 5 showed the strongest inhibitory effect, with the inhibitory rate reaching 48.67%. [Conclusion] It is proven that dl-mandelic acid is the main active component for the antithrombotic effect of peach kernels.

Abstract:[Objective] The aim of the study is to explore the effects of electron beam irradiation on the sterilization and quality of Auricularia heimuer （A. heimuer) powder and pave a new way for sterilization of the powder. [Method] The A. heimuer powder samples were sterilized by electron beam irradiation at the doses within the range of 0~10 kGy. The effects of irradiation at doses of 2, 4, 6, 8, 10 kGy on the microbial count were studied. The effects of irradiation at doses of 2, 4, 6 kGy on the main components, nutritional value regarding amino acids, antioxidant activity, and sensory quality were also investigated. [Result] Electron beam irradiation killed or inhibited the microorganisms in A. heimuer powder, and the D₁₀ value of the total colony count was 1.77 kGy. When the dose was 4 kGy, the mass fractions of crude polysaccharides (14.80%), protein (13.60%), medicinal amino acids (6.34%), and essential amino acids (4.00%) in A. heimuer powder were the highest, and they all had differences from those in the control group (P<0.05). Moreover, the A. heimuer powder irradiated at 4 kGy showed improvement in the nutritional value regarding amino acids (P<0.05), enhancement in the antioxidant activity (P<0.05), and no significant changes in the mass fraction of total sugar (73.4%) or sensory quality (P>0.05). [Conclusion] Electron beam irradiation could be used for the sterilization of A. heimuer powder. The best effect was achieved at an irradiation dose of 4 kGy, under which the processed A. heimuer powder had the strongest antioxidant activity and the highest nutritional value regarding amino acids without causing quality decline.

Abstract:[Objective] The author aimed to explore the microbial diversity and quality variations of Pu-erh tea at different processing stages (manufacturing, fermentation, and storage). [Method] The microorganisms isolated from tea were cultured and molecularly identified by using plate coating and PCR sequencing technologies. The quality of Pu-erh tea was determined by sensory evaluation, component detection, and electronic nose. [Result] A total of 218 strains of bacteria were isolated and purified, with 77, 59, and 82 strains isolated from sun-dried raw tea (SQ) at the manufacturing stage, fermented ripened Pu-erh tea (SC1) during the fermentation stage, and cellar-aged ripened Pu-erh tea stored for 2 years (SC2) during the storage stage, respectively, and no fungi were isolated. The 16S rRNA gene sequencing revealed that the bacteria mainly classified as Achromobacter, Bacillus, Bacterium, Brachybacterium, Brevibacillus, Chryseobacterium, Staphylococcus, Curtobacterium, Raoultella, Enterobacter, Pantoea, Herbaspirillum, Paenibacillus, Kocuria, Siccibacter, and Xanthomonas. Bacillus was the common dominant bacterium in SQ, SC1, and SC2, with relative isolation frequencies (RDF) of 35.06%, 55.93%, and 36.59%, respectively when incubated at 37 ℃. In addition to Bacillus, the main bacteria in SQ were Chryseobacterium (19.48%), Achromobacter (12.99%), and Curtobacterium (6.49%). The main bacteria in SC1 were Streptomyces (11.86%), Curtobacterium 10.17%), and Kocuria (10.17%). The main bacteria in SC2 were Paenibacillus (15.85%), Enterobacter (12.20%), and Staphylococcus (10.98%). The levels of heavy metals, agricultural residues, pathogenic bacteria, powder, total ash content, crude fiber, tea polyphenol, and water extract of Pu-erh tea all complied with national standards. The mass fractions of total free amino acids, thearubigins, theabrownins, and fluoride, as well as the mass fraction of catechins and other tea polyphenols, were higher than those in SC2, while the mass fractions of caffeine and tea polysaccharides in SC2 were higher than those in SC1. The mass fractions of caffeine and theabrownin in SC1 and SC2 were higher than those in SQ, while the mass fractions of total free amino acid, theanine, thearubigins, and theaflavin as well as the mass fraction of catechins and other tea polyphenols, were all lower than those in SQ. Aroma substances were mainly concentrated in methyl groups, p-sulfide, hydrocarbons, alcohols, aldehydes, ketones, aromatic components, organic sulfide, and benzene. [Conclusion] This study provides a theoretical basis for the development and promotion of the Pu-erh tea industry.

Abstract:[Objective] The aim of the study is to explore the suitable roasting temperature for macadamia nuts. [Method] Macadamia nuts were roasted at 140, 160, and 180 ℃ for 5 min, respectively. The changes in volatile substances, total phenols, total flavonoids, and antioxidant capacity were determined. [Result] Macadamia nuts mainly contained six kinds of fatty acids: arachic acid, arachidonic acid, oleic acid, linoleic acid, palmitic acid, and palmitoleic acid. Unsaturated fatty acids, mainly linoleic acid and palmitoleic acid, accounted for more than 83%. Roasting temperature had no significant effect on the relative content and composition of fatty acids in macadamia nuts. After roasting treatment, the mass fraction of total phenols and the mass concentration of total flavonoids, as well as the antioxidant activity of macadamia nuts were increased, indicating that roasting improved the biological activity and antioxidant activity of macadamia nuts. Higher roasting temperature increased the mass fraction of total phenols and the mass concentration of total flavonoids in macadamia nuts, and improved their antioxidant capacity. Macadamia nuts roasted at high temperatures produced Maillard reaction products and lipid peroxidation products. It was found that roasting at 160 ℃ for 5 min resulted in a higher relative content of aroma substances in macadamia nuts, imparting a desirable roasted aroma. In addition, the relative molecular weights of macadamia protein were about 50 000 and 40 000. The stability of macadamia nut protein was better after roasting at 160 ℃. [Conclusion] Roasting at 160 ℃ for 5 min can better improve the sensory and nutritional qualities of macadamia nuts.

Abstract:[Objective] The aim of the study is to clarify the influences of different sterilization methods on volatile organic compounds of Dendrobium officinale beverage. [Method] Gas chromatography-ion mobility spectrometry (GC-IMS) was employed to determine the composition and relative content changes of volatile organic compounds in Dendrobium officinale beverage under no sterilization, thermosonication, and high-temperature sterilization. [Result] 61 volatile organic compounds were identified in Dendrobium officinale beverage by GC-IMS, including 20 aldehydes, 13 alcohols, 12 ketones, 7 esters, 3 heterocycles, 3 alkenes, 2 ethers, and 1 acid. Thermosonication had little effect on the volatile organic compounds of Dendrobium officinale beverage, and the composition and relative content of volatile organic compounds were similar before and after thermosonication. High-temperature sterilization had great effects on the volatile organic compounds of Dendrobium officinale beverage, and the relative content of compounds such as 2-methyl-3-furanthiol, ethyl pentanoate, 2-heptanone, isovaleraldehyde, and 5-methylfurfural significantly increased. The results of difference analysis showed that Dendrobium officinale beverages treated by thermosonication and high-temperature sterilization had differences in characteristic flavor compounds and could be well distinguished. [Conclusion] Thermosonication is helpful to maintain the original flavor of Dendrobium officinale beverage, while high-temperature sterilization can enrich the aroma of the beverage. The results can provide a basis for the quality identification and sterilization process selection of Dendrobium officinale beverage.

Abstract:[Objective] This study aimed to prepare rabbit anti-Chlamydomonas reinhardtii (C. reinhardtii) Tubby-like protein 2 (TLP2) polyclonal antibodies for the identification of C. reinhardtii tlp2 mutants and to investigate the biological functions of TLP2 of C. reinhardtii. [Method] The tlp2 gene fragment was obtained by polymerase chain reaction (PCR), and the prokaryotic expression vectors pET-28a(+?)?-tlp2 and pMAL-c2x-tlp2 were constructed. The two recombinant plasmids were transferred to Escherichia coli (E. coli) BL21(DE3) by chemical transformation, and the expression of the fusion proteins 6×His-TLP2 and MBP-TLP2 was induced by isopropyl β-D-thiogalactoside (IPTG). New Zealand white rabbits were immunized with the purified 6×His-TLP2. [Result] The antiserum titer determined by indirect ELISA method reached 1:51 200. The antiserum was purified by protein A and antigen affinity chromatography. The TLP2 antibodies specifically recognized TLP2 of C. reinhardtii at a dilution factor of 1:500. [Conclusion] Highly specific and sensitive rabbit polyclonal antibodies against TLP2 of C. reinhardtii were prepared, and a tlp2 mutant was identified. The mutant can be used for subsequent study on the role of TLP2 of C. reinhardtii of in cilium formation and cilium signal transduction.

Abstract:[Objective] To investigate the effects of co-administration of Gastrodia elata (G. elata) and probiotics on the digestive function and intestinal microbiota in rats. [Method] SD rats were utilized to explore the effects of G. elata extract on the digestive function, and the mass fractions of total phenols and polysaccharides in the extract were determined. The extract was then combined with probiotics for gavage in rats. After 30 d of gavage, the body weight, food intake, food utilization rate, pepsin activity, and mass concentrations of gastrin (GAS) and somatostatin (SS) were measured. The intestinal microbiota structure was analyzed by 16S rRNA sequencing. [Result] The co-administration group showed increases in body weight, food intake, pepsin activity, pepsin excretion, and GAS level compared with the control group (P<0.05), with a decrease in SS level (P<0.05). Additionally, the co-administration of G. elata and probiotics adjusted the intestinal microbiota structure by increasing the relative abundance of beneficial bacteria such as Lactobacillaceae, Ruminococcaceae, and Lachnospiraceae. [Conclusion] The co-administration of G. elata and probiotics positively affects the digestive function in rats and holds the potential for development.

Abstract:[Objective] To enhance the stress resistance of lactic acid bacteria in seabuckthorn juice by inducing the adaptive evolution of the bacteria under the stress of main organic acids. [Method] First, two strains of lactic acid bacteria suitable for fermenting seabuckthorn juice were selected from eight strains isolated from Jiangshui collected from Ningxia. Adaptive evolution was induced under L-malic acid and quinic acid stress, and the two strategies were compared regarding the performance in improving stress resistance of the strains. Subsequently, strain LP-1 was subjected to L-malic acid stress for 125 d. [Result] The fermentation of seabuckthorn juice with the modified strain LP-1-679 showed a lactic acid yield of 0.4 g/L and a malic acid consumption rate of 88.24%, which were 2.67 and 6.60 times those of the original strain, respectively. Moreover, strain LP-1-679 exhibited genetic stability. Compared with the original strain, strain LP-1-679 led to a decrease in the mass fraction of saturated fatty acids (C14:0 and C21:0) and an increase in the mass fraction of unsaturated fatty acids (C16:1, C18:1n9c, and C22:1n9). [Conclusion] A lactic acid bacterial strain with good fermentation performance and strong genetic stability is obtained after acid stress treatment. This strain might resist acid stress by adjusting the composition of fatty acids in the cell membrane.

Abstract:[Objective] To investigate the feasibility of substituting lactose for isopropyl-β-D-1-thiogalactopyranoside (IPTG) in inducing efficient expression of 3-ketosteroid-Δ1-dehydrogenase (KstD) in Escherichia coli (E. coli） BL21(DE3). [Method] Upon the established IPTG-induced protocol for obtaining high yields of soluble and catalytically active recombinant protein SZD-KstD, the lactose induction parameters under shake-flask culture conditions were optimized. Subsequently, high-density fermentation was conducted in a 15 L bioreactor. Critical process parameters influencing expression of the recombinant protein SZD-KstD were evaluated, including addition time, lactose induction method, induction duration, and carbon/nitrogen feeding protocols. [Result] The maximum amounts of SZD-KstD and bacteria were obtained under the induction with lactose at the final concentration of 0.2 mmol/L. Since lactose can be used as a carbon source at the same time, adding lactose in three batches outperformed adding it in one batch. Under lactose induction conditions, SZD-KstD accounted for 39.58% of total soluble protein content, which was not significantly different from that under IPTG induction. [Conclusion] Lactose, as a cheap and efficient inducer, can replace IPTG for the large-scale fermentation of KstD, which solves a major problem for the preparation of steroid drugs by bioenzyme method and provides a reference for the production of other recombinant proteins.

Abstract:[Objective] The aim of this study is to address the insolubility of elastin derived from animals and the aggregation of recombinant elastin-like proteins, and to enhance the elastin potential application in functional foods. [Method] In view of the above problems, resilin 16 (R16) derived from insects, immunoglobulin G domain B1 (GB1) from Streptococcus, and the Ure2 sequence of aa 1~80 Ure2(1-80) from Saccharomyces cerevicae were linked with the RGD sequence (a binding site of cells that promote cell adhesion) to construct the soluble supramolecular elastin. The cytotoxicity of the supramolecular elastin to C2C12 cells as well as its biosafety was evaluated. Furthermore, the supramolecular elastin was compared with hyaluronic acid (HA) and pigskin collagen in terms of the cell proliferation-promoting effect and antioxidant capacity. [Result] The supramolecular elastin had no toxic effect on cells and did not induce obvious inflammation after subcutaneous injection, demonstrating high biosafety. The self-assembled fibril promoted cell proliferation, and it showcased stronger scavenging ability against four kinds of free radicals and protective effect against H₂O₂-induced damage of L929 cells than HA and pigskin collagen. [Conclusion] The obtained supramolecular elastin has high biosafety, cell proliferation-promoting effect, and antioxidant capacity, serving as a new material for the development of functional food.

Abstract:[Objective] To study the effects of different fermentation conditions on the mycelial pellet morphology of Aspergillus terreus (A. terreus) AterHaut1 and aflatoxin B₁ (AFB₁) degradation efficency. [Method] Single factor experiments were carried out to investigate the mycelial pellet morphology and AFB₁ degradation rates under different inoculation volume fractions, fermentation temperatures, and shaker speeds. The fermentation conditions were optimized by Box-Behnken design combined with response surface methodology. [Result] The optimal fermentation conditions were obtained as follows: shaker speed of 145 r/min, inoculation volume fraction of 0.17%, and fermentation temperature of 35 ℃. The actual degradation rate of AFB₁ by the fermentation supernatant obtained under the optimal fermentation conditions reached 96.34%. At this time, the average diameter of mycelial pellets was 1.35 mm, with even distribution between 1.20 mm and 1.50 mm. [Conclusion] Optimizing the fermentation conditions of A. terreus AterHaut1 can improve the degradation rate of AFB₁.

Abstract:[Objective] The aim of the study is to establish a method for the simultaneous detection of residues of two neonicotinoid pesticides (thiacloprid and acetamiprid) in tea. [Method] Firstly, the theoretical Raman spectra of thiacloprid and acetamiprid were calculated with the Gaussian, and the chemical groups corresponding to the peaks of the two pesticides were determined by comparison with the conventional Raman spectra, with Raman peaks at 585 cm^-1 and 626 cm^-1 as the characteristic peaks, respectively. Silver-coated gold nanoparticles (Au@AgNPs) were further prepared as the enhanced substrate for surface-enhanced Raman spectroscopy (SERS). The standard curves for simultaneous detection of thiacloprid and acetamiprid were established. [Result] The optimal coagulant was 1.0 mol/L Na₂SO₄. The limits of detection of thiacloprid and acetamiprid in tea samples were 0.5 mg/kg and 1.0 mg/kg, respectively, which were lower than the residue limit in tea that was specified in the national standard. The recovery rates of thiacloprid and acetamiprid were within 85.0%~106.9%, which met the requirements of the detection method. [Conclusion] The established method achieves the simultaneous detection of thiacloprid and acetamiprid in tea.

Abstract:[Objective] To establish a method for the quantitative detection of residues of hexachlorocyclohexanes (BHCs) and dichlorodiphenyltrichloroethanes (DDTs) in rice by combining QuEChERS with gas chromatography-tandem mass spectrometry (GC-MS/MS). [Method] Rice samples were mixed with water and extracted with acetonitrile-acetic acid solution. The extracts were purified by PSA/C18 solid phase extraction. After high-speed centrifugation and concentration by nitrogen flushing, the samples were detected by GC-MS/MS, and the internal standard method was used for quantitation. [Result] Four BHCs and four DDTs showed excellent linearity within the mass concentration range of 6.25~100.00 ng/mL, with R² greater than 0.999. The limits of detection and quantitation were within the ranges of 0.000 2~0.000 5 mg/kg and 0.000 5~0.002 0 mg/kg, respectively. The average recovery rates of matrix addition were between 92.27% and 98.76%, and the relative standard deviations (RSD) were between 0.44% and 1.88%. Quality control samples for validation were detected by the established method, and the results were within the true value range. The comparison results of the samples participating in the assessment were all satisfactory. [Conclusion] The established method demonstrates high sensitivity, good repeatability, and high accuracy, being suitable for rapid determination of residues of BHCs and DDTs in rice.