Table of Content

01 January 2026, Volume 49 Issue 1

Previous Issue   

Basic Research

Comparative Analysis of the miR-26a Delivery Efficacy of Ultrasound-Treated Liposomes and Milk Exosomes

ZHAI Jianing, YUAN Zekun, CHEN Jiahui, LÜ Wenjia, LI Aili, WANG Kaili

2026, 49(1):  1-8.  DOI: 10.7506/rykxyjs1671-5187-20251013-067

Asbtract ( )   HTML ( )   PDF (3104KB) ( )  

References | Related Articles | Metrics

Based on previous research suggesting that milk exosomes specifically express miR-26a, this study optimized the miR-26a encapsulation efficiency of liposomes through ultrasonic treatment, and it also evaluated the in vitro digestion performance of the ultrasonic-treated liposomes and compared its anti-inflammatory activity with that of natural milk exosomes. Single-factor experiments were conducted to optimize the molar charge ratio of cationic liposome vector to nucleic acid (N/P), ultrasonication time, and ultrasonic power for the preparation of miR-26a-encapsulated liposomes. The results demonstrated that when the N/P ratio was 4, ultrasonication time was 15 min, and ultrasonic power was 300 W, the encapsulation efficiency reached its peak of (89.51 ± 1.37)%, with uniform particle size distribution and homogeneous morphology. In vitro simulated digestion experiments showed that the retention rate of miR-26a in the ultrasonic-treated liposomes (58%) was higher than that in the conventional liposomes (24%). Cell function experiments confirmed that the ultrasonic-treated liposomes not only enhanced the viability of normal Caco-2 cells but also effectively inhibited lipopolysaccharide (LPS)-induced inflammatory responses, significantly restoring cell viability under inflammatory conditions. Additionally, it reduced NO release and down-regulated the secretion of the inflammatory cytokines interleukin 6 (IL-6), tumor necrosis factor α, and IL-1β, while effectively controlling the generation of reactive oxygen species. Notably, the ultrasonic-treated liposomes showed no significant differences from milk exosomes in terms of cell viability regulatory and inflammation inhibitory effects. In summary, this study demonstrates that ultrasonic can significantly improve the miR-26a delivery efficiency of liposomes.

Molecular Mechanisms Underlying the Proliferative Effects of ω-3 Polyunsaturated Fatty Acids on Intestinal Epithelial Cells

QUAN Heng, LIN Yingying, WANG Yuqi, ZHANG Yafei, SONG Sijia, GUO Huiyuan

2026, 49(1):  9-15.  DOI: 10.7506/rykxyjs1671-5187-20250917-062

Asbtract ( )   HTML ( )   PDF (3423KB) ( )  

References | Related Articles | Metrics

The proliferation of small intestinal epithelial cells is fundamental to intestinal development and barrier function maintenance in infants and young children. To investigate the effects and mechanisms of ω-3 polyunsaturated fatty acids (docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA)), commonly used in infant formula, on this process, this study employed the rat intestinal epithelial cell line 6 (IEC-6) as a model. After DHA and EPA treatment at different combinations of concentration (1, 10, 50, 100 μmol/L) and duration 12, 24, 36, 48 h, cell viability was assessed using the cell counting kit-8 and 5-ethynyl-2’-deoxyuridine assays, and the mRNA and protein expression of key molecules involved in the Wnt/β-catenin signaling pathways were analyzed via real-time quantitative polymerase chain reaction and Western blot. The results showed that both DHA and EPA significantly promoted the proliferation of IEC-6 cells, with optimal concentrations of 100 and 10 μmol/L, respectively, and an optimal treatment duration of 24 h. Specifically, treatment with 100 μmol/L DHA and 10 μmol/L EPA for 24 h increased cell viability by nearly 4- and 3.5-fold compared to the control group (P < 0.001), respectively. Both DHA and EPA activated the Wnt/β-catenin signaling pathway, significantly upregulating the mRNA and protein expression of cell proliferation-related genes such as cyclin D1 and β-catenin (P < 0.05, P < 0.01, or P < 0.001). These findings indicate that DHA and EPA enhance intestinal epithelial cell proliferation by activating the Wnt signaling pathway.

Biotechnology

Whole Genome Analysis and Functional Prediction of Ligilactobacillus cholophilus BD7642

REN Quanlu

2026, 49(1):  16-22.  DOI: 10.7506/rykxyjs1671-5187-20251020-070

Asbtract ( )   HTML ( )   PDF (2121KB) ( )  

References | Related Articles | Metrics

A novel strain of Ligilactobacillus cholophilus, designated BD7642, was isolated from pickled potherb mustard (Brassica juncea Coss.) in Shanghai. The complete genome sequence of the strain was obtained using a combination of PacBio and Illumina sequencing. To characterize this strain and explore its potential probiotic functions, we performed comprehensive genomic analyses. The results showed that the genome of L. cholophilus BD7642 was 1 587 935 bp in size and encoded 1 530 genes (no plasmids detected). Functional annotation and secondary metabolite synthesis analysis revealed that L. cholophilus BD7642 contained gene clusters for the biosynthesis of the bacteriocin mutacin 1140 and type III polyketide synthases and possessed a great capacity for environmental adaptation. ResFinder analysis indicated the absence of antibiotic resistance genes. Comparative genomics uncovered the genomic uniqueness of L. cholophilus BD7642. This study provides a deep understanding of L. cholophilus BD7642 and offers a reference for exploiting its probiotic potential.

Processing technology

Effects of Different Sterilization Methods on the Stability and Casein Structure in Camel Milk

ZHOU Ying, SUN Wancheng, LUO Yihao

2026, 49(1):  23-32.  DOI: 10.7506/rykxyjs1671-5187-20251013-068

Asbtract ( )   HTML ( )   PDF (5694KB) ( )  

References | Related Articles | Metrics

The effects of heat sterilization and microwave sterilization on the stability and casein structure of fresh camel milk were compared. The microwave sterilization conditions were optimized using single factor experiments and response surface methodology based on Box-Behnken design. Changes in the structure and properties of camel milk casein after sterilization were investigated using a differential scanning calorimeter, a Fourier transform infrared spectrometer, and a scanning electron microscope. The centrifugal sedimentation rate of protein and the total number of colonies were taken as response variables, the optimum conditions were determined as follows: pH 7.0, microwave power 560 W and microwave irradiation time 120 s. After microwave treatment under these conditions, the centrifugal sedimentation rate of protein was 6.96%, and no bacterial colonies were detected. Differential scanning calorimetry (DSC) plot showed that microwave treatment resulted in higher enthalpy of camel milk casein compared with heat sterilization, indicating a lower degree of denaturation and higher stability. The results of scanning electron microscopy showed that both sterilization methods destroyed the micellar structure of casein to varying degrees, resulting in cross-linking and aggregation. However, after microwave sterilization, the casein showed ordered aggregation, forming small aggregates that assembled into an ordered network structure. Appropriately increasing the pH of camel milk before sterilization was conducive to its stability. Different sterilization methods had a significant effect on the secondary structure of camel milk casein. Both microwave and heat sterilization reduced the relative contents of α-helix and β-turn in the casein. The relative content of β-sheet in heat-sterilized camel milk casein was the highest, indicating the most significant change in the secondary structure of the protein.In summary, this study revealed the stability of camel milk and the structural change of camel milk casein under different sterilization conditions, which can help address the poor stability of thermally sterilized camel milk at this stage.

Package & Storage

Effects of Mold-Inhibiting Lactic Acid Bacteria on the Storage Quality of Fresh Cheese

ZI Jiaxin, LI Xiaodong, LIU Lu, ZHANG Xiuxiu, ZHANG Ziyi, DU Xinyu, CHAI Jing

2026, 49(1):  33-40.  DOI: 10.7506/rykxyjs1671-5187-20250928-064

Asbtract ( )   HTML ( )   PDF (2988KB) ( )  

References | Related Articles | Metrics

Fresh cheese is rich in nutrients but is highly susceptible to mold contamination, resulting in a short shelf life and poor long-term storage stability. This study investigated the effects of three lactic acid bacterial (LAB) strains with mold-inhibiting properties, Lactiplantibacillus plantarum HH-LP56 (L1), Lactobacillus acidophilus HH-LA26 (L2), and Limosilactobacillus reuteri PB-LR09, on the quality characteristics of fresh cheese during storage. The results indicated that compared with the nisin supplemented group and the control group without any preservative added, addition of any of the three antifungal strains significantly improved the quality characteristics of fresh cheese during storage. In terms of antibacterial properties, the LAB groups performed excellently. After 60 days of storage, the total colony counts in groups L1 and L2 were significantly lower than those in the L3, nisin, and control groups (P < 0.05), and the mold counts did not exceed the limit stipulated by the Chinese national standard (≤ 50 CFU/g). The mold count in group L1 remained within the limit after 90 days, whereas the mold counts in the L3, nisin, and control groups exceeded the limit after 60 days of storage. With regard to quality characteristic, the LAB groups showed brighter color (higher brightness value, lower redness and yellowness values), superior texture, and richer milky aroma. The abundance of volatile flavor compounds was evidently higher in the LAB groups than in the control group. In total, 66 volatile flavor compounds were detected in group L1, with a richer and mellower flavor. In conclusion, the three LAB strains exhibited stronger antifungal effects than did nisin, with L1 showing the best performance. These strains can effectively extend the shelf life of fresh cheese while maintaining its desirable flavor and texture.

Analysis & Detection

Quantitative Detection of Mold in Fermented Milk Based on Droplet Digital Polymerase Chain Reaction

CHEN Jia, CHEN Linfeng, LI Mengyu, JIANG Shaojia, XIAO Xiao

2026, 49(1):  41-47.  DOI: 10.7506/rykxyjs1671-5187-20251104-079

Asbtract ( )   HTML ( )   PDF (2404KB) ( )  

References | Related Articles | Metrics

To address the issue of the long detection cycle and difficult quantitative analysis of molds in fermented milk, this study developed a systematic method for the detection of molds in commercial fermented milk by using droplet digital polymerase chain reaction (ddPCR) to absolutely quantify the copy number of target sequences in samples. The optimal ddPCR reaction system and amplification program were determined. The proposed method performed well in terms of specificity, sensitivity and quantitative accuracy. It specifically amplification target molds (Aspergillus niger, Penicillium citrinum, and Penicillium chrysogenum), with no cross-reactivity with yeasts, lactic acid bacteria, or pathogenic bacteria. Sensitivity tests indicated that at the minimum detectable concentration (0.625 ng/μL), the positive copy number was 9 copies/μL. In addition, this method established linear equations between bacterial suspension concentration and DNA concentration, as well as between DNA concentration and gene copy number, with correlation coefficients greater than 0.99, and based on them, a linear equation between bacterial suspension concentration and gene copy number was developed. The results of the ddPCR method for artificially contaminated samples were consistent with those of the national standard method (GB 4789.15-2016). Moreover, the method enables absolute quantification without the need for a standard curve, effectively shortening the detection cycle.

Reviews

Recent Progress in Enzymatic Preparation of Immunomodulatory Peptides from Milk

HONG Qing, YONG Jingyi, WANG Guojiao, YANG Yang, JIA Xiangfei

2026, 49(1):  48-54.  DOI: 10.7506/rykxyjs1671-5187-20251104-076

Asbtract ( )   HTML ( )   PDF (1589KB) ( )  

References | Related Articles | Metrics

Immunomodulatory peptides from milk (IPM) are a class of polypeptides with various biological activities such as immunomodulatory, antibacterial, and antioxidant properties. Compared to microbial fermentation, enzymatic hydrolysis offers distinct advantages including high specificity for cleavage sites, defined product structures, and superior process controllability, making it the preferred strategy for producing high-potency, standardized IPMs. This review summarizes recent advances in the enzymatic preparation of IPMs, focusing on enzyme selection strategies and the structure-activity relationship of IPMs regarding charge, hydrophobicity, and peptide chain length. Furthermore, it discusses the bidirectional mechanisms of IPMs in modulating innate and adaptive immunity, and highlights core industrial challenges such as debittering, membrane fouling control, and low oral bioavailability. Future research should integrate artificial intelligence assisted virtual screening and nano-encapsulation technologies to overcome bottlenecks in the application of IPMs.

Recent Progress in Analytical Techniques for the Detection of Flavor Compounds in Dairy Products

YUAN Xuefeng, LIU Shishen, MA Shangchao, LI Fen, JIA Yiming, ZHANG Zuoli, NIU Xiyue, LI Jie, XU Qian

2026, 49(1):  55-61.  DOI: 10.7506/rykxyjs1671-5187-20251020-071

Asbtract ( )   HTML ( )   PDF (1369KB) ( )  

References | Related Articles | Metrics

Dairy flavor is a product of the synergistic interaction between microbial metabolism and processing techniques, with its unique sensory characteristics being critical determinants of product competitiveness and quality control. This review systematically summarizes the formation mechanism of dairy flavor and the principles and applications of major identification, screening, and quality evaluation technologies, with a focus on the advantages, limitations, and complementary relationships of gas chromatography-mass spectrometry, liquid chromatography-mass spectrometry, near-infrared (NIR) spectroscopy, nuclear magnetic resonance, and intelligent sensory technologies. Based on a systematic comparison of existing techniques, a “technology characteristic-detection objective-application scenario” matching framework is proposed, aiming to shift the current research paradigm from reliance on “single-technology identification” toward an integrated approach based on “multi-technology fusion perception”. This shift provides a theoretical foundation and technical support for establishing a standardized and intelligent dairy flavor evaluation system. Future developments are expected to focus on the construction of multi-technology collaborative platforms, in-depth interpretation of complex data using artificial intelligence algorithms, and online quality control enabled by miniaturized devices.

A Review on the Dynamic Changes and Influencing Factors of Immunoglobulin Contents in Human Milk

JIA Hongxin, SU Miya, CHEN Wenliang

2026, 49(1):  62-69.  DOI: 10.7506/rykxyjs1671-5187-20250909-059

Asbtract ( )   HTML ( )   PDF (1588KB) ( )  

References | Related Articles | Metrics

Human milk provides adequate nutrition for infants’ early development and is rich in immunologically active substances, protecting infants against diseases before their own immune systems mature. Secretory immunoglobulin A (sIgA), IgM, and IgG, the major immunologically active substances in human milk, have been most extensively studied. The concentration and composition of Igs in human milk change with the lactation period, which is influenced not only by lactation stages (colostrum, transitional and mature milk) but also by the lactating mother’s living environment, dietary nutrition, gestational age, and other factors. This paper systematically reviews the concentrations and influencing factors of Igs in human milk from different countries and regions, with the aim of providing references for the in-depth research and application development of active components in human milk.

Comparative Analysis of Nutrient Indicators and Limits Specified in Domestic and International Standards for Infant and Young Child Formulae

SHI Ying, LU Jiaojiao

2026, 49(1):  70-83.  DOI: 10.7506/rykxyjs1671-5187-20250826-056

Asbtract ( )   HTML ( )   PDF (1591KB) ( )  

References | Related Articles | Metrics

The standards for infant and young child formulae of China, the Codex Alimentarius Commission (CAC), the European Union (EU), Australia and New Zealand (ANZ), and the United States were compared with respect to energy, protein, fat, and optional ingredients to identify differences in nutritional requirements. It was found?that China has established stringent standards for infant, follow-on, and young child formulae. The Chinese and CAC standards for infant and follow-on formulae are highly consistent, with nearly identical limits set for essential nutrients such as energy, total fat, total carbohydrates, protein, and vitamins. The major difference between them is that the addition of inositol and L-carnitine is mandated by the CAC, while these compounds are classified as optional ingredients in China. The limits set by China for essential ingredients such as energy, fat, and carbohydrates are consistent with those from the EU standards, while the limits for 13 nutrients including vitamins A and D are higher than those from the EU standards. Additionally, the EU has mandated the addition of inositol, L-carnitine, and docosahexaenoic acid, and has approved seven human milk oligosaccharides (HMOs) for use in infant formula. In contrast, only two HMOs have been approved in China. These variations can be attributed to differences in breast milk composition data, infant dietary patterns, nutritional deficiency status, and regulatory philosophies among countries. This paper clarifies the similarities and differences in the nutritional requirements of domestic and international standards for infant and young child formulae, providing crucial insights for refining China’s regulatory revisions and guiding consumers in selecting products that meet the nutritional needs of local infants and young children.