Effect of a Dairy Cow's Feeding System on the Flavor of Raw Milk: Indoor Feeding or Grazing.

The flavor of fresh, raw milk is considered to be the key to maintaining the quality of dairy products, and is very crucial in affecting a consumer's choice. To better understand the differences in flavor of fresh milk between feeding patterns, we conducted the following study. Twelve Holstein cows reared in pure grazing mode and twelve reared intensively in medium to large farms were selected from the Xinjiang Uygur Autonomous Regions at the same time, and the flavor of their raw milk was analyzed. Aroma profiles and taste attributes were assessed by electronic nose and electronic tongue, respectively, and volatile flavor compounds were characterized and quantified by Headspace-Solid Phase Microextraction/Gas Chromatography-Mass Spectrometry. Thirteen volatile compounds were identified in the indoor feeding pattern and 12 in the grazing; most of them overlapped. W1S, W2S and W5S were the main contributing sensors of the electronic nose for the overall assessment of the aroma profile. Raw milk from grazing had more intense astringency, bitterness, sourness and richness in taste compared to indoor feeding. Different dietary conditions may contribute to a variety of aroma profiles. Oxime-, methoxy-phenyl-, octadecanoic acid, furfural and dodecanoic acid were the key volatile flavor compounds of grazing. Meanwhile, raw milk from indoor feeding patterns was unique in 2-nonanone, heptanoic acid and n-decanoic acid. All three detection techniques were valid and feasible for differentiating raw milk in both feeding patterns, and the compounds were significantly correlated with the key sensors by correlation analysis. This study is promising for the future use of metabolic sources of volatile organic compounds to track and monitor animal feeding systems.

Impact of Beauveria bassiana on antioxidant enzyme activities and metabolomic profiles of Spodoptera frugiperda.

Spodoptera frugiperda is a pest that poses a serious threat to the production of food and crops. Entomopathogenic fungi, such as Beauveria bassiana, have shown potential for S. frugiperda control. However, the mechanism of this biological control of pathogens is not fully understood, such as how antioxidant enzyme activities and metabolic profiles in S. frugiperda larvae are affected when infected by entomopathogenic fungi. This study assessed the antioxidant enzyme activities and shift in metabolomic profile in the S. frugiperda larvae infected with B.bassiana. The results indicate a pattern of initial increase and subsequent decrease in the activities of superoxide dismutase, catalase, and peroxidase in the B.bassiana-infected larvae. And the enzyme activities at 60 h of infection ended significantly lower than those of the uninfected larvae. A total of 93 differential metabolites were identified in the B.bassiana-infected larvae, of which 41 metabolites were up-regulated and 52 were down-regulated. These metabolites mainly included amino acids, nucleotides, lipids, carbohydrates, and their derivatives. Among the changed metabolites, cystathionine, l-tyrosine, l-dopa, arginine, alpha-ketoglutaric acid, d-sedoheptulose-7-phosphate and citric acid were significantly decreased in B. bassiana-infected larvae. This indicated that the fungal infection might impair the ability of S. frugiperda larvae to cope with oxidative stress, leading to a negative impact of organism fitness. Further analyses of key metabolic pathways reveal that B. bassiana infection might affect purine metabolism, arginine biosynthesis, butanoate metabolism, and phenylalanine metabolism of S. frugiperda larvae. The findings from this study will contribute to our understanding of oxidative stress on immune defense in insects, and offer fundamental support for the biological control of S. frugiperda.

Extraction Optimization, Characterization and Biological Activities of Polysaccharide Extracts from Nymphaea hybrid.

In this study, polysaccharide-rich Nymphaea hybrid extracts (NHE) were obtained using the ultrasound-assisted cellulase extraction (UCE) method optimized by response surface methodology (RSM). The structural properties and thermal stability of NHE were characterized by Fourier-transform infrared (FT-IR), high-performance liquid chromatography (HPLC) and thermogravimetry-derivative thermogravimetry (TG-DTG) analysis, respectively. Moreover, the bioactivities of NHE, including the antioxidant, anti-inflammatory, whitening and scratch healing activities were evaluated by different in vitro assays. NHE conveyed a good ability to scavenge against the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals and inhibit the hyaluronidase activity. NHE can effectively protect the HaCaT cells against oxidative damage by inhibiting the intracellular reactive oxygen species (ROS) production in the H2O2 stimulation assays and promoting the proliferation and migration in the scratch assays. In addition, NHE was proven to inhibit melanin production in B16 cells. Collectively, the above results seem to be the evidence needed to promote the potential of NHE to be regarded as a new functional raw material in the cosmetics or food industries.

Enteric nervous system damage caused by abnormal intestinal butyrate metabolism may lead to functional constipation.

Functional constipation (FC) is a high morbidity gastrointestinal disease for which dysfunction in the enteric nervous system is a major pathogenesis mechanism. To enhance our understanding of the involvement of intestinal microbiota and its metabolites in the pathogenesis of FC, we conducted a shotgun metagenomic sequencing analysis of gut microbiota and serum short-chain fatty acids (SCFAs) analysis in 460 Chinese women with different defecation frequencies. We observed that the abundance ofFusobacterium_varium, a butyric acid-producing bacterium, was positively correlated (P = 0.0096) with the frequency of defecation; however, the concentrations of serum butyric acid was negatively correlated (P = 3.51E-05) with defecation frequency. These results were verified in an independent cohort (6 patients with FC and 6 controls). To further study the effects of butyric acid on intestinal nerve cells, we treated mouse intestinal neurons in vitro with various concentrations of butyrate (0.1, 0.5, 1, and 2.5 mM). We found that intestinal neurons treated with 0.5 mM butyrate proliferated better than those in the other treatment groups, with significant differences in cell cycle and oxidative phosphorylation signal pathways. We suggest that the decreased butyrate production resulting from the reduced abundance of Fusobacterium in gut microbiota affects the proliferation of intestinal neurons and the energy supply of intestinal cells. However, with FC disease advancing, the consumption and excretion of butyric acid reduce, leading to its accumulation in the intestine. Moreover, the accumulation of an excessively high amount of butyric acid inhibits the proliferation of nerve cells and subsequently exacerbates the disease.

Fluorescent Sensor Based on Magnetic Separation and Strand Displacement Amplification for the Sensitive Detection of Ochratoxin A.

Ochratoxin A (OTA) is a common mycotoxin, and it is a significant threat to human health throughout the food chain. In this study, a sensitive and specific fluorescent sensor based on magnetic separation technology combined with chain displacement amplification was developed for fast and easy detection of OTA in food. The designed strand displacement amplification can improve the sensitivity for the detection, and the magnetic nanomaterials can provide a large surface area, thus enhancing the capture efficiency of the target from the sample. Based on those designs, the experimental results showed that the proposed method displayed excellent performance. The linearity range was 0.5-128.0 ng/mL. The detection limit was 0.125 ng/mL; the relative standard deviations were 3.92-7.71%. Additionally, the developed method was satisfactorily applied to determine OTA in wheat, corn, and red wine samples at three spiked levels (1.0, 8.0, and 64.0 ng/mL). The recoveries ranged from 85.45 to 107.8% for wheat flour, 101.34 to 108.35% for corn flour, and 91.15 to 93.80% for red wine, respectively. Compared with high-performance liquid chromatography, the proposed method showed a lower limit of detection and equal recovery. Hence, the designed method is a potential and good detecting tool for OTA residue analysis in complex matrix samples.

Molecular Design of Porous Organic Polymer-Derived Carbonaceous Electrocatalysts for Pinpointing Active Sites in Oxygen Reduction Reaction.

The widespread application of fuel cells is hampered by the sluggish kinetics of the oxygen reduction reaction (ORR), which traditionally necessitates the use of high-cost platinum group metal catalysts. The indispensability of these metal catalysts stems from their ability to overcome kinetic barriers, but their high cost and scarcity necessitate alternative strategies. In this context, porous organic polymers (POPs), which are built up from the molecular level, are emerging as promising precursors to produce carbonaceous catalysts owning to their cost-effectiveness, high electrical conductivity, abundant active sites and extensive surface area accessibility. To enhance the intrinsic ORR activity and optimize the performance of these electrocatalysts, recognizing, designing, and increasing the density of active sites are identified as three crucial steps. These steps, which form the core of our review, serve to elucidate the link between the material structure design and ORR performance evaluation, thereby providing valuable insights for ongoing research in the field. Leveraging the precision of polymer skeletons based on molecular units, POP-derived carbonaceous catalysts provide an excellent platform for in-depth exploration of the role and working mechanism for the specific active site during the ORR process. In this review, the recent advances pertaining to the synthesis techniques and electrochemical functions of various types of active sites, pinpointed from POPs, are systematically summarized, including heteroatoms, surficial substituents and edge/defects. Notably, the structure-property relationship, between these active sites and ORR performance, are discussed and emphasized, which creates guidelines to shed light on the design of high-performance ORR electrocatalysts.

CCR2-overexpressing biomimetic carrier-free nanoplatform for enhanced cascade ferroptosis tumor therapy.

Ferroptosis-based nanoplatforms have shown great potential in cancer therapy. However, they also face issues such as degradation and metabolism. Carrier-free nanoplatforms consisting of active drugs can effectively avoid the security issues associated with additional carrier ingredients. Herein, a biomimetic carrier-free nanoplatform (HESN@CM) was designed to treat cancer by modulating cascade metabolic pathways of ferroptosis. CCR2-overexpressing macrophage membrane-modified HESN can target cancer cells via the CCR2-CCL2 axis. The acidic tumor microenvironment (TME) can disrupt the supramolecular interaction of HESN, releasing hemin and erastin. Then, erastin could induce cancer cells ferroptosis by inhibiting system XC- pathways, while hemin, a vital component of blood to transport oxygen, could be broken down by heme oxygenase-1 (HO-1), increasing the intracellular Fe2+ concentration to induce cancer cells' ferroptosis further. Meanwhile, erastin could enhance the activity of HO-1, further promoting the release of Fe2+ from hemin. As a result, HESN@CM demonstrated superior therapeutic efficacy in both primary and metastatic tumors in vitro and in vivo. The carrier-free HESN@CM provided cascade ferroptosis tumor therapy strategies for potential clinical application. STATEMENT OF SIGNIFICANCE: CCR2-overexpressing biomimetic carrier-free nanoplatform (HESN@CM) was designed for cancer treatment by modulating metabolic pathways of ferroptosis. HESN modified with CCR2-overexpressing macrophage membrane can target tumor cells via the CCR2-CCL2 axis. HESN was composed of hemin and erastin without additional vectors. Erastin could directly induce ferroptosis, while hemin could be broken down by heme oxygenase-1 (HO-1), increasing the intracellular Fe2+ concentration to enhance ferroptosis further. Meanwhile, erastin could improve the activity of HO-1, promoting the release of Fe2+ from hemin. Therefore, HESN@CM with good bioavailability, stability, and simple preparation can realize cascade ferroptosis tumor therapy and have the potential prospect of clinical translation.

Metagenomic and Untargeted Metabolomic Analysis of the Effect of Sporisorium reilianum Polysaccharide on Improving Obesity.

Gut microbiota plays an important role in the pathophysiology of obesity. Fungal polysaccharide can improve obesity, but the potential mechanism needs further study. This experiment studied the potential mechanism of polysaccharides from Sporisorium reilianum (SRP) to improve obesity in male Sprague Dawley (SD) rats fed with a high-fat diet (HFD) using metagenomics and untargeted metabolomics. After 8 weeks of SRP (100, 200, and 400 mg/kg/day) intervention, we analyzed the related index of obesity, gut microbiota, and untargeted metabolomics of rats. The obesity and serum lipid levels of rats treated with SRP were reduced, and lipid accumulation in the liver and adipocyte hypertrophy was improved, especially in rats treated with a high dose of SRP. SRP improved the composition and function of gut microbiota in rats fed with a high-fat diet, and decreased the ratio of Firmicutes to Bacteroides at the phylum level. At the genus level, the abundance of Lactobacillus increased and that of Bacteroides decreased. At the species level, the abundance of Lactobacillus crispatus, Lactobacillus helveticus, and Lactobacillus acidophilus increased, while the abundance of Lactobacillus reuteri and Staphylococcus xylosus decreased. The function of gut microbiota mainly regulated lipid metabolism and amino acid metabolism. The untargeted metabolomics indicated that 36 metabolites were related to the anti-obesity effect of SRP. Furthermore, linoleic acid metabolism, phenylalanine, tyrosine, and tryptophan biosynthesis, and the phenylalanine metabolism pathway played a role in improving obesity in those treated with SRP. The study results suggest that SRP significantly alleviated obesity via gut-microbiota-related metabolic pathways, and SRP could be used for the prevention and treatment of obesity.

Ethnicity and sex-specific 99th percentile upper reference limits of high-sensitivity cardiac troponin I among adults in Xinjiang, China.

OBJECTIVES: To determine the 99th percentile upper reference limit (URL) of high-sensitivity cardiac troponin I (hs-cTnI) in a healthy population in Xinjiang, China, and investigate the impact of ethnicity, sex, and age on this limit. DESIGN AND METHODS: From September 2018 to March 2022, 5,090 Han and Uyghur adults aged 20-79 years were recruited. After questionnaire screening, 2,970 participants with physical and/or laboratory normality were enrolled. Participants recruited between September 2018 and October 2021 (2,109/2,970) were evaluated by ARCHITECTi2000 to determine the 99th percentile URL of hs-cTnI. The results were then validated in 861/2,970 participants recruited from November 2021 to March 2022. A criterion of ≤ 10% of test results falling outside the original determined value was used to determine whether the newly established reference intervals were valid. RESULTS: The hs-cTnI concentration was higher among Uyghurs than among Han participants (p < 0.001). The 99th percentile URLs were 17.52 ng/L for all participants, 18.96 ng/L for Uyghur, and 16.93 ng/L for Han. Hs-cTnI concentration was also correlated with sex and age. In the Han and Uyghur groups, male participants had a higher hs-cTnI concentration than female participants (p < 0.001); the 99th percentile URLs of hs-cTnI among male and female participants were 17.80 vs. 13.67 ng/L and 19.47 vs. 16.52 ng/L, respectively. Stratified by age, hs-cTnI concentrations were higher in participants aged > 60 years than in those of other age categories (p < 0.001), in both the Han and Uyghur groups. Finally, <2% of these test results exceeded the newly established reference, validating the results. CONCLUSIONS: This study established the 99th percentile URLs of hs-cTnI in the Xinjiang. Ethnicity and sex influence the value and should be considered.

Clinical significance of peripheral blood-derived inflammation markers combined with serum eotaxin-2 in human colorectal cancer.

To investigate the value of serum eotaxin-2, neutrophil/lymphocyte ratio (NLR), and platelet/lymphocyte ratio (PLR) in the diagnosis and prognosis of colorectal cancer (CRC). The association between different clinicopathological characteristics and eotaxin-2, NLR, and PLR in different patient groups was evaluated. The combined detection indicator and the combined detection's predictive effect on distant metastasis were examined. The receiver operating characteristic (ROC) curve was drawn to evaluate the efficacy of combined detection. The association between eotaxin-2, inflammation markers, and postoperative complications was assessed. Multivariate analysis to investigate the factors affecting the prognosis of patients with CRC. We detected a marked positive correlation between NLR and PLR (p < 0.05, r= 0.209). The AUC of serum eotaxin-2 combined with inflammation markers was 0.889, which was higher than single diagnosis. Compared with the single eotaxin-2 test, the combined detection of eotaxin-2 and inflammation markers might improve the specificity of CRC assessment. In univariate analysis, age, surgical method, high eotaxin-2, and high NLR were associated with postoperative complications. In multivariate analysis, age (≥ 60 years), high eotaxin-2, and high NLR were independent risk elements influencing postoperative complications of CRC. The distant metastasis, TNM staging -Ⅳ stage, NLR ≥ 3.18, and PLR ≥ 193 were independent factors affecting the prognosis of patients with CRC. The combined detection of eotaxin-2 and inflammatory markers has a particular value in improving the diagnosis of CRC, predicting distant metastasis, and guiding the frequency of reexamination after radical resection of CRC.

Ginsenoside Rd attenuated hyperglycemia via Akt pathway and modulated gut microbiota in streptozotocin-induced diabetic rats.

Ginsenoside Rd is a protopanaxadiol abundant in Panax ginseng and Panax notoginseng. It has been reported that ginsenoside Rd possesses various health benefits, such as anti-diabetic, anti-tumor and anti-inflammatory. This work explored the effects of ginsenoside Rd on hyperglycemia and gut microbiota in streptozotocin-induced diabetic rats. Results showed that 5-week ginsenoside Rd (20 mg/kg) treatment significantly improved hyperglycemia in diabetic rats. Besides, ginsenoside Rd promoted glycogen synthesis via activating Akt pathway. It also inhibited hepatic gluconeogenesis, which was associated with inhibiting phosphoenolpyruvate carboxykinase and glucose-6-phosphatase. We further found that ginsenoside Rd treatment increased the diversity of gut microbiota, increased the abundance of beneficial bacteria, such as SMB53, rc4-4 and Ruminococcus, and reduced the abundance of conditional pathogenic bacteria. These results indicated that ginsenoside Rd has the potential for diabetic intervention.

Whole exome sequencing reveals novel variants associated with diminished ovarian reserve in young women.

Background: Diminished ovarian reserve is one of the most important causes of female infertility. In the etiology study of DOR, besides age, it is known that chromosomal abnormality, radiotherapy, chemotherapy and ovarian surgery can result in DOR. For young women without obvious risk factors, gene mutation should be considered as a possible cause. However, the specific molecular mechanism of DOR has not been fully elucidated. Methods: In order to explore the pathogenic variants related to DOR, twenty young women under 35 years old affected by DOR without definite factors damaging ovarian reserve were recruited as the research subjects, and five women with normal ovarian reserve were recruited as the control group. Whole exome sequencing was applied as the genomics research tool. Results: As a result, we obtained a set of mutated genes that may be related to DOR, where the missense variant on GPR84 was selected for further study. It is found that GPR84Y370H variant promotes the expression of proinflammatory cytokines (TNF-α, IL12B, IL-1ß) and chemokines (CCL2, CCL5), as well as the activation of NF-κB signaling pathway. Conclusion: In conclusion, GPR84Y370H variant was identified though analysis for WES results of 20 DOR patients. The deleterious variant of GPR84 could be the potential molecular mechanism of non-age-related pathological DOR through its role in promoting inflammation. The findings of this study can be used as a preliminary research basis for the development of early molecular diagnosis and treatment target selection of DOR.

Phenothiazine-Based LSD1 Inhibitor Promotes T-Cell Killing Response of Gastric Cancer Cells.

Histone lysine specific demethylase 1 (LSD1) has been recognized as an important epigenetic target for cancer treatment. Although several LSD1 inhibitors have entered clinical trials, the discovery of novel potent LSD1 inhibitors remains a challenge. In this study, the antipsychotic drug chlorpromazine was characterized as an LSD1 inhibitor (IC50 = 5.135 µM), and a series of chlorpromazine derivatives were synthesized. Among them, compound 3s (IC50 = 0.247 µM) was the most potent one. More importantly, compound 3s inhibited LSD1 in the cellular level and downregulated the expression of programmed cell death-ligand 1 (PD-L1) in BGC-823 and MFC cells to enhance T-cell killing response. An in vivo study confirmed that compound 3s can inhibit MFC cell proliferation without significant toxicity in immunocompetent mice. Taken together, our findings indicated that the novel LSD1 inhibitor 3s tethering a phenothiazine scaffold may serve as a lead compound for further development to activate T-cell immunity in gastric cancer.

Recent advances on catalysts for photocatalytic selective hydrogenation of nitrobenzene to aniline.

Selective hydrogenation of nitrobenzene (SHN) is an important approach to synthesize aniline, an essential intermediate with extremely high research significance and value in the fields of textiles, pharmaceuticals and dyes. SHN reaction requires high temperature and high hydrogen pressure via the conventional thermal-driven catalytic process. On the contrary, photocatalysis provides an avenue to achieve high nitrobenzene conversion and high selectivity towards aniline at room temperature and low hydrogen pressure, which is in line with the sustainable development strategies. Designing efficient photocatalysts is a crucial step in SHN. Up to now, several photocatalysts have been explored for photocatalytic SHN, such as TiO2, CdS, Cu/graphene and Eosin Y. In this review, we divide the photocatalysts into three categories based on the characteristics of the light harvesting units, including semiconductors, plasmonic metal-based catalysts and dyes. The recent progress of the three categories of photocatalysts is summarized, the challenges and opportunities are pointed out and the future development prospects are described. It aims to give a clear picture to the catalysis community and stimulate more efforts in this research area.

Analysis of Volatile Organic Compounds in Milk during Heat Treatment Based on E-Nose, E-Tongue and HS-SPME-GC-MS.

Volatile organic compounds (VOCs) make up milk flavor and are essential attributes for consumers to evaluate milk quality. In order to investigate the influence of heat treatment on the VOCs of milk, electronic nose (E-nose), electronic tongue (E-tongue) and headspace solid-phase microextraction (HS-SPME)-gas chromatography-mass spectrometry (GC-MS) technology were used to evaluate the changes in VOCs in milk during 65 °C heat treatment and 135 °C heat treatment. The E-nose revealed differences in the overall flavor of milk, and the overall flavor performance of milk after heat treatment at 65 °C for 30 min is similar to that of raw milk, which can maximize the preservation of the original taste of milk. However, both were significantly different to the 135 °C-treated milk. The E-tongue results showed that the different processing techniques significantly affected taste presentation. In terms of taste performance, the sweetness of raw milk was more prominent, the saltiness of milk treated at 65 °C was more prominent, and the bitterness of milk treated at 135 °C was more prominent. The results of HS-SPME-GC-MS showed that a total of 43 VOCs were identified in the three types of milk-5 aldehydes, 8 alcohols, 4 ketones, 3 esters, 13 acids, 8 hydrocarbons, 1 nitrogenous compound, and 1 phenol. The amount of acid compounds was dramatically reduced as the heat treatment temperature rose, while ketones, esters, and hydrocarbons were encouraged to accumulate instead. Furfural, 2-heptanone, 2-undecanone, 2-furanmethanol, pentanoic acid ethyl ester, 5-octanolide, and 4,7-dimethyl-undecane can be used as the characteristic VOCs of milk treated at 135 °C. Our study provides new evidence for differences in VOCs produced during milk processing and insights into quality control during milk production.

Discovery of acridine-based LSD1 inhibitors as immune activators targeting LSD1 in gastric cancer.

LSD1 is overexpressed in various cancers and promotes tumor cell proliferation, tumor expansion, and suppresses immune cells infiltration and is closely associated with immune checkpoint inhibitors therapy. Therefore, the inhibition of LSD1 has been recognized as a promising strategy for cancer therapy. In this study, we screened an in-house small-molecule library targeting LSD1, an FDA-approved drug amsacrine for acute leukemia and malignant lymphomas was found to exhibit moderate anti-LSD1 inhibitory activity (IC50 = 0.88 µM). Through further medicinal chemistry efforts, the most active compound 6x increased anti-LSD1 activity significantly (IC50 = 0.073 µM). Further mechanistic studies demonstrated that compound 6x inhibited the stemness and migration of gastric cancer cell, and decreased the expression of PD-L1 (programmed cell death-ligand 1) in BGC-823 and MFC cells. More importantly, BGC-823 cells are more susceptible to T-cell killing when treated with compound 6x. Moreover, tumor growth was also suppressed by compound 6x in mice. Altogether, our findings demonstrated that acridine-based novel LSD1 inhibitor 6x may be a lead compound for the development of activating T cell immune response in gastric cancer cells.

Fabricating Uniform TiO2-CeO2 Solid Solution Supported Pd Catalysts by an In Situ Capture Strategy for Low-Temperature CO Oxidation.

Support properties regulation has been a feasible method for the improvement of noble metal catalytic performance. For Pd-based catalysts, TiO2-CeO2 material has been widely used as an important support. However, due to the considerable discrepancy in the solubility product constant between titanium and cerium hydroxides, it is still challenging to synthesize a uniform TiO2-CeO2 solid solution in the catalysts. Herein, an in situ capture strategy was constructed to fabricate a uniform TiO2-CeO2 solid solution as supports for an enhanced Pd-based catalyst. The obtained Pd/TiO2-CeO2-iC catalyst possessed enriched reactive oxygen species and optimized CO adsorption capability, manifesting a superior CO oxidation activity (T100 = 70 °C) and stability (over 170 h). We believe this work provides a viable strategy for precise characteristic modulation of composite oxide supports during the fabrication of advanced noble metal-based catalysts.

Biocontrol Efficacy of Bacillus methylotrophicus TA-1 Against Meloidogyne incognita in Tomato.

Root-knot nematodes (RKNs) are harmful plant-parasitic nematodes of tomatoes, which can cause significant yield losses. Therefore, there is increasing interest in exploring the application of bacterial nematicides. The bacterium Bacillus methylotrophicus TA-1 is a broad-spectrum biocontrol agent; however, its effect on RKNs control remains largely unclear. In this study, the toxicity of B. methylotrophicus TA-1 against Meloidogyne incognita was investigated in vitro and the potential of B. methylotrophicus TA-1 to decrease infection of RKNs in tomato were evaluated in pot and field trials. Results showed that B. methylotrophicus TA-1 exhibited high nematicidal activity against second-stage juveniles (J2s) and eggs of M. incognita with 50% lethal concentration (LC50) values of 5.80 and 7.00 × 108 colony forming units (CFU)/mL, respectively. In the pot experiments and field trials conducted in 2020 and 2021, tomato plants treated with B. methylotrophicus TA-1 soil drench applied once at 3; 6 and 9 × 108 CFU/plant had significantly higher plant height and greater yield compared to the untreated control. Tomato yields of the treated plots with B. methylotrophicus TA-1 in two consecutive years' field trials were between 53.4-66.1 and 52.8-61.5 t/ha, while in the untreated control 49.7 and 48.2 t/ha, for each year respectively. The lowest population densities of M. incognita at 30 and 60 days after treatment were 119 and 135 J2s per 100 g soil in 2020 and 43 and 118 J2s in 2021 in TA-1 treated plots. The lowest gall index of 4.7 and 3.3 in 2020 and 2021, respectively and highest yield were all observed in the TA-1 at 9 × 108 CFU/plant treated plants, with no significant differences with the commercial control abamectin. These results provided a basis for further studies of B. methylotrophicus TA-1 formulations, application doses, frequencies, and mechanisms of action, which are necessary before it could be used as a component of integrated management programs to manage RKNs in tomato production.