Alfalfa root rot is one of the devastating soil-borne diseases caused by complex pathogenic microorganisms. It has severely limited the stable and high-yielding, as well as the forage quality of alfalfa. It is often required to identify the regionally dominant pathogenic strains and then screen highly efficient biocontrol agents with targeted suppression, particularly for the eco-friendly control of the destructive disease. This study aimed to explore the region-specific biocontrol solution in the typical high-incidence area of alfalfa root rot in Pingluo County, Ningxia Hui Autonomous Region, China. High-throughput sequencing was employed to compare the rhizosphere microbial communities in the rhizosphere soils of healthy and diseased alfalfa plants. A systematic investigation was also conducted to characterize the rhizosphere microbial imbalance during the progression of alfalfa root rot. According to the microbial community analysis, the pathogenic fungus, Paraphoma rhaphiolepidis, which was highly associated with the occurrence of alfalfa root rot, was successfully isolated and accurately identified for the first time in this specific region. Furthermore, a highly efficient antagonistic bacterium strain, designated as ARF-SR2, was isolated and then screened from the rhizosphere soil of healthy alfalfa plants, ultimately identified as Bacillus velezensis after molecular and physiological-biochemical identification. In vitro antagonism tests demonstrated that Bacillus velezensis ARF-SR2 exhibited remarkably significant antagonistic activity against the target pathogen P. rhaphiolepidis, indicating an inhibition rate of 68.81%, while the minimum inhibitory concentration (MIC) of its fermentation supernatant was determined to be 1 mg/mL. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations further confirmed that the fermentation supernatant of ARF-SR2 significantly disrupted the mycelial morphology and cellular ultrastructure of P. rhaphiolepidis, eventually leading to the dissolution of the pathogen’s cell wall, condensation of cytoplasmic contents, and disintegration of internal organelles. Functional characterization assays indicated that the ARF-SR2 also shared multiple beneficial functional traits, including nitrogen fixation, phosphorus solubilization, secretion of various hydrolytic enzymes, siderophore production, and indoleacetic acid (IAA) synthesis. A strong performance was coupled to form biofilms. There was a strain with the excellent rhizosphere colonization and substantial potential for plant growth. Pot experiments further validated that the biocontrol efficacy of ARF-SR2 achieved a control efficiency of 64.90% against alfalfa root rot. Notably, the strain significantly alleviated the growth inhibition of alfalfa induced by P. rhaphiolepidis stress, as key growth indicators, such as plant height, root length, fresh weight, and dry weight, increased by 36.87%-93.44% (P<0.05), compared with the pathogen-infected control group. Simultaneously, ARF-SR2 treatment significantly elevated the soluble protein content and antioxidant enzyme activities (including SOD and CAT) in alfalfa plants, thereby enhancing the plant's stress tolerance and disease resistance. In summary, the strain Bacillus velezensis ARF-SR2 exhibited extremely promising prospects in the green control of alfalfa root rot in Ningxia. A synergistic combination of multiple mechanisms included the targeted disease suppression, efficient plant growth promotion, and stable rhizosphere colonization. This strain can serve as the functional microorganism for the engineered microbial agents, thereby integrating “disease control and growth promotion”.

Low-molecular-mass chondroitin sulfate (CS) have attracted wide attention due to their better bioavailability and biological activity than highmolecular-mass CS. To obtain low-molecular-mass sulfate chondropolysaccharides with higher anti-colorectal cancer activity, sturgeon chondroitin sulfate (SCS) from the hybrid sturgeon Acipenser schrenckii × Huso dauricus was enzymatically depolymerized. Response surface methodology was used to optimize the enzymatic process based on inhibitory activity against the proliferation of HT-29 cells. The optimal enzymatic conditions were determined as 0.103 IU/mg, 1.005 mg/mL and 87 min for enzyme dosage, substrate concentration, and enzymatic digestion time, respectively. Furthermore, SCS-F2 with low molecular mass and high anticancer activity was prepared by ultrafiltration. In order to explore its safety for consumption, the acute toxicity of SCS-F2 was evaluated by using an animal model. The experimental results showed that SCS-F2 has no adverse effects on body mass, food intake, blood biochemical indexes or visceral tissues while reducing the number of aberrant colonic crypts, indicating that SCS-F2 has inhibitory and preventive effects on colorectal cancer and meets the safety requirements of food and health products. Therefore, SCS-F2 is safe and non-toxic, and has anti-colorectal cancer activity.

Tomatoes are one of the most widely cultivated vegetables in China and are popular among consumers. In recent years, as the demand for healthy food has grown, the quality of tomatoes has aroused increasing attention. While tomatoes are generally uniform in shape, there are significant differences in size, fruit type and color among tomato varieties, and tomatoes contain a variety of nutrients with complex chemical structures, so its quality is difficult to assess. The traditional tomato quality testing methods are subjective, destructive, time-consuming and laborious, and thus cannot meet the demand of large-scale quality testing. Recently, with the development of non-destructive testing technologies, new detection methods such as machine learning, multispectral techniques, and electronic nose/electronic tongue have been developed and applied for the rapid and non-destructive testing of tomato quality. This paper provides a summary of the development and application of artificial intelligence based on image recognition, electronic nose technology and spectroscopic technologies for the non-destructive testing of tomatoes in order to provide a reference for future research and development of tomato quality inspection.

Chondroitin sulfate (CS) is one of the main bioactive compounds in animal cartilage. In this study, the anti-inflammatory activity of sturgeon-derived chondroitin sulfate (SCS) was evaluated in the dextran sulfate sodium (DSS)-induced BALB/c mice model. Orally administration of SCS significantly alleviated the DSS-induced colitis symptoms, including the reduction of crypt depth, inhibition of the abnormal crypt foci formation, down-regulation of the proinflammatory biomarkers (NO, interleukin (IL)-6, IL-1β and tumor necrosis factor-α) and up-regulation of the anti-inflammatory biomarkers (IL-10 and IL-4). The gut microbiota analysis revealed that SCS alters the intestinal microbiota composition in colitis mice, especially the increase of the relative abundance of Ruminococcaceae and Lachnospiraceae. This alternation further induced primary bile acids convert into secondary bile acids. With SCS administration, the levels of deoxycholic acid (DCA) and litho cholic acid (LCA) were increased by 1.5- and 2.5-fold, respectively. The stimulated secretion of DCA and LCA showed further activation of the NF-κB signaling pathway, thereby suppressing the inflammatory response and attenuating inflammatory bowel disease (IBD) in mice. This study provided a valuable strategy for colitis prevention and treatment with sturgeon cartilage by-products.

Sea buckthorn (Hippophae rhamnoides L.) is a natural homologous substance of medicine and food. Polysaccharide, as one of its primary active components, has very superior biological activity and can be used as a dietary supplement for functional foods, with good commercial prospects. Although initial progress has been made in the study of sea buckthorn polysaccharides, related studies have been fragmented and lacked systematic and generalization. This manuscript presents a critical analysis and systematic summary of the extraction and purification methods, structural characterization and physicochemical properties, biological activity and potential mechanisms, and structure-activity relationships of sea buckthorn polysaccharides. Accumulating evidence has indicated that sea buckthorn polysaccharides, which were widely prepared by water extraction and column chromatography purifications, exhibited exhibit superior biological activities in vitro and in vivo, including antioxidant, immunomodulatory, anti-inflammatory, hepatorenal protective, antibacterial, antiviral, and prebiotic activities. After analysis, it was concluded that there is a correlation between the relevant activities of sea buckthorn polysaccharides and that the structure of sea buckthorn polysaccharides has a great influence on their biological activity. We reviewed the challenges and limitations of sea buckthorn polysaccharides, summarized the critical aspects, and provided suggestions for potential breakthroughs in the research and application of sea buckthorn polysaccharide.

Weizmannia coagulans (formerly Bacillus coagulans) is a spore-forming and lactic acid-producing bacterium. It has recently attracted much attention from researchers and food manufacturers due to its probiotic functions and stability in processing and storage. W. coagulans is capable of improving gut health through the regulation of gut microbiota, modulation of immunity, and improving digestibility and metabolism. Spores, germinated cells and metabolites of W. coagulans modulate the gut micro-environment and further affect other organs. W. coagulans is an environment-friendly probiotic since it can contribute to the host by reconstructing the balance of gut microbiota and only temporarily resides in the intestine after administration. W. coagulans has been generally recognized as safe (GRAS) by the US Food and Drug Administration (FDA), thus it is an ideal probiotic for improving gut health. The merit of its stability in processing and storage provides W. coagulans spores many possibilities for its use in various types of functional foods. This review presents an overview of the characteristics of W. coagulans that make it an ideal probiotic candidate and highlights the proposed health benefits with scientific evidence conferred by the administration of W. coagulans.