FEMS MICROBIOLOGY ECOLOGY
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2023
·Vol. 99
·期 12
·
IF 4.2
Guo Zhonghui,Li Jieming,Luo Di,Zhang Mingxia
Microcystin (MC)-producing (MC+) and MC-free (MC−) Microcystis always co-exist and interact during Microcystis-dominated cyanobacterial blooms (MCBs), where MC+Microcystis abundance and extracellular MC-content (EMC) determine the hazard extent of MCBs. The current study elucidated intraspecific interaction between MC+ and MC−Microcystis at various nitrogen (N) levels (0.5–50 mg/L) and how such N-mediated interaction impacted algicidal and EMC-inhibiting effect of luteolin, a natural bioalgicide. Conclusively, MC+ and MC−Microcystis were inhibited mutually at N-limitation (0.5 mg/L), which enhanced the algicidal and EMC-inhibiting effects of luteolin. However, at N-sufficiency (5–50 mg/L), MC−Microcystis promoted MC+ ecotype growth and dominance, and such intraspecific interaction induced the cooperative defense of two ecotypes, weakening luteolin's algicidal and EMC-inhibiting effects. Mechanism analyses further revealed that MC+Microcystis in luteolin-stress co-culture secreted exopolymeric substances (EPSs) for self-protection against luteolin-stress and also released more EMC to induce EPS-production by MC−Microcystis as protectants, thus enhancing their luteolin-resistance and promoting their growth. This study provided novel ecological implications of MC−Microcystis toward MC+ ecotype in terms of assisting the dominant establishment of MC+Microcystis and cooperative defense with MC+ ecotype against luteolin, which guided the application of bioalgicide (i.e. luteolin) for MCBs and MCs pollution mitigation in different eutrophication-degree waters.
研究领域:
生态学
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环境科学
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水生生物学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF FOOD PROTECTION
·
2025
·
IF 2.8
Yaoyao Su,Jun Huang,Xiaoman Chen,Gang Yang,Kewei Chen,Muying Du,Zsolt Zalán,Ferenc Hegyi,Sameh Awad,Jianquan Kan
The contamination of spices with aflatoxin (AF) raises concerns regarding its health risks. In this study, 51 samples of dried red chili peppers (including 10 varieties collected from three regions) were used to investigate the AF contamination of dried red chili peppers sold in China, and the toxigenic characteristics of Aspergillus flavus strains isolated from chili peppers. AFs were identified using immunoaffinity column purification, derivatization, and high-performance liquid chromatography with fluorescence detection. The AF content in various types of dried red chili peppers sold in the Chinese market was generally low (≤ 7.19 µg/kg), below the limit of the relevant standard (10 µg/kg). The frequency of suspected A. flavus strains isolated from chili peppers was high (24/51), with a high toxigenic strain ratio of 29.17%. Further investigation revealed that 25–30 ℃ was the optimal temperature for toxin production by these toxigenic strains. This indicated that dried chilled peppers have a significant risk of AF contamination. Therefore, the findings of this study suggest that long-term storage of dried chili peppers should be conducted at temperatures below 25 ℃ or above 37 ℃ to mitigate the problem of AF contamination exceeding the levels allowed by the standards, providing new insights for the prevention and control of AF contamination of dried red chili peppers.
研究领域:
食品科学
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微生物学
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毒理学
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农业科学
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分析化学
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DOI
PubMed
高影响因子
EUROPEAN FOOD RESEARCH AND TECHNOLOGY
·
2014
·Vol. 240
·期 3
·627-634
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IF 1.387
Ma Huihui,Zhang Niya,Sun Lvhui,Qi Desheng
Aflatoxin contamination levels vary from crop to crop, suggesting that it is of great significance to explore the effects of different substrates on aflatoxins production. In this study, the effects of corn, wheat, peanut, and soybean on aflatoxin B 1 (AFB 1 ) production by Aspergillus parasiticus were investigated, and the effects of corn germ, wheat germ, soybean, and peanut oils on the production of AFB 1 by A . parasiticus in the corresponding defatted substrates were evaluated at the rates of 2, 5, 10, and 15 g/100 g of substrate. The effects of the combinations of different oils with different defatted substrates on the accumulation of AFB 1 by A . parasiticus were also studied. AFB 1 concentration was determined by HPLC. The results indicated that high-lipid substrates of soybean and peanut had significantly higher AFB 1 production than low-fat substrates of wheat and corn throughout the entire incubation period (15 days) in both autoclaved and non-autoclaved grains. Corn germ, wheat germ, soybean, and peanut oils with different doses could effectively stimulate AFB 1 accumulation, and AFB 1 production was determined by the oil content of the substrates. Our results suggest that the oil content of substrates is one of the factors affecting AFB 1 production by A . parasiticus and that the composition and content of the substrates may also play a role.
研究领域:
食品科学
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微生物学
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产品关联
DOI
高影响因子
JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE
·
2021
·Vol. 102
·期 9
·3522-3534
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IF 3.639
Wenbo Wang,Xin Yang,Junfeng Li,Zhihao Dong,Jie Zhao,Tao Shao,Xianjun Yuan
BACKGROUND This study aims to reveal the effects of hexanoic acid on the microbial communities, fermentation, and the hygienic quality of corn silages with or without fungal infection. Fungal-infested (FI) and non-infested (NFI) whole-crop corn samples were separately ensiled without (control, CON) or with hexanoic acid (Hex, 90% purity) at 0.2 g·kg −1 fresh weight (FW). RESULT The addition of Hex accelerated the pH decline during the first 5 days of ensiling regardless of fungal infestation. The lactic acid (LA) concentration in Hex silages was lower than that in CON during 45 days of ensiling; however the FI-Hex silage had the highest LA concentration among treatments on day 90. The Hex silage showed lower aflatoxin B 1 (AFB 1 ), zearalenone (ZEA), and deoxynivalenol (DON) concentrations than CON for FI silages. On day 5, the addition of Hex decreased the relative abundance of Klebsiella , Pantoea , and Enterobacter compared with CON, regardless of fungal infestation. This inhibitory effect lasted until day 90 for NFI silages but disappeared for FI silages on day 90. The fungal infestation resulted in the accumulation of Candida (34.05%) and Wickerhamomyces (19.46%). Hex decreased the relative abundance of Asperigillus , Issatchenkia, and Penicillium for NFI silages on day 5; however, its inhibitory effects were not observed in FI silages on day 5. CONCLUSION Fungal infestation was associated with poor fermentation and hygienic quality of corn silage. Adding Hex accelerated the pH decline and maintained the antifungal activity until 90 days of ensiling, attenuating adverse effects of fungal infestation on the fermentation and preventing the accumulation of mycotoxins in corn silages. © 2021 Society of Chemical Industry.
研究领域:
农业
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微生物学
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食品科学
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动物营养
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DOI
PubMed
高影响因子
Frontiers in Immunology
·
2017
·
IF 6.429
Ren Wenkai,Yin Jie,Xiao Hao,Chen Shuai,Liu Gang,Tan Bie,Li Nengzhang,Peng Yuanyi,Li Tiejun,Zeng Benhua,Li Wenxia,Wei Hong,Yin Zhinan,Wu Guoyao,Hardwidge Philip R.,Yin Yulong
Intestinal microbiota has critical importance in pathogenesis of intestinal infection; however, the role of intestinal microbiota in intestinal immunity during enterotoxigenic Escherichia coli (ETEC) infection is poorly understood. The present study tested the hypothesis that the intestinal microbiota is associated with intestinal interleukin-17 (IL-17) expression in response to ETEC infection. Here, we found ETEC infection induced expression of intestinal IL-17 and dysbiosis of intestinal microbiota, increasing abundance of γ-aminobutyric acid (GABA)-producing Lactococcus lactis subsp. lactis. Antibiotics treatment in mice lowered the expression of intestinal IL-17 during ETEC infection, while GABA or L. lactis subsp. lactis administration restored the expression of intestinal IL-17. L. lactis subsp. lactis administration also promoted expression of intestinal IL-17 in germ-free mice during ETEC infection. GABA enhanced intestinal IL-17 expression in the context of ETEC infection through activating mechanistic target of rapamycin complex 1 (mTORC1)-ribosomal protein S6 kinase 1 (S6K1) signaling. GABA–mTORC1 signaling also affected intestinal IL-17 expression in response to Citrobacter rodentium infection and in drug-induced model of intestinal inflammation. These findings highlight the importance of intestinal GABA signaling in intestinal IL-17 expression during intestinal infection and indicate the potential of intestinal microbiota-GABA signaling in IL-17-associated intestinal diseases.
研究领域:
微生物学
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免疫学
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病理学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
Toxins
·
2025
·Vol. 17
·期 12
·
IF 4
Hui Zhang,Yuying Su,Xinnan Wang,Ying Ren,Jinfeng Li,Jianping Han
Polygalae Radix, a traditional Chinese medicine for insomnia and memory disorders, is highly susceptible to fungal contamination and mycotoxin production (especially byAspergillus flavus) during storage, compromising its safety and efficacy. Therefore, in this study, high-throughput sequencing was employed to evaluate the dynamic changes in fungal communities during the storage of Polygalae Radix and to analyze common mycotoxin-producing genera. Furthermore, the inhibitory effects of peppermint essential oil (PEO) onA. flavuswere assessed through fumigation treatments, combined with colony counting and quantification of aflatoxins. Results showed the following: (1) Storage for 1–3 months significantly altered the fungal structure, promoting saprophytic and pathogenic fungi (e.g.,Wallemia,Paraphoma,Didymella,Cladosporium…) and increasing the relative abundance of mycotoxin producers likePenicillium,Aspergillus, andFusarium(notably,Penicilliumincreased from 0.28–2.33% to 5.39–80.43%). Additionally,A. flavus, capable of producing aflatoxins, was detected in samples stored for two months (RM2). (2) Antifungal tests demonstrated that PEO significantly inhibited the common fungi in Polygalae Radix. At 10 μL/g, it suppressed fungal growth and significantly reduced aflatoxin B1(AFB1) and total aflatoxins (AFT, including AFB1, AFB2, AFG1, and AFG2) levels (p< 0.05). At 10 μL/g, AFB1and AFT were reduced to undetectable levels. PEO can serve as a green and effective protective strategy to inhibitA. flavusduring the storage of Polygalae Radix and control aflatoxin contamination.
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DOI
PubMed
高影响因子
Food Additives and Contaminants Part A-Chemistry Analysis Control Exposure & Risk Assessment
·
2022
·
IF 3.549
Jiachang Feng,Jianpeng Dou,Wenfu Wu
The competitive inhibition of aflatoxigenic fungi by non-aflatoxigenic Aspergillus flavus has proved to be an effective method to prevent and control peanut aflatoxin contamination, and most of the currently used inoculum carriers are grains. In this study, the reliability and efficiency of replacing grain kernels with novel chitosan-coated alginate-poly(N-isopropylacrylamide) (PNIPAAm) beads impregnated with biochar (CSACB) were evaluated. Characterisation of the beads was performed by SEM, thermogravimetry analysis (TGA), and swelling properties analyses. The optimised CSACB beads had good physical stability, shelf life, and entrapment efficiency. In addition, the water-holding capacity and porous structure were excellent, as the biochar provided a beneficial microenvironment for the attachment and microbial growth of the biocontrol fungus. The effect of reducing aflatoxin in peanuts was verified experimentally. Collectively, the novel CSACB beads are suitable carriers of non-aflatoxigenic A. flavus for the biocontrol of peanut aflatoxin.
研究领域:
农业科学
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食品科学
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生物技术
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微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）