CARBOHYDRATE POLYMERS
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2025
·
IF 12.5
Zhuo Xu,Bin Wu,Chunhua Wu,Qian Chen,Yanfei Niu,Zhengjun Shi,Kun Liang,Xiaoping Rao
In order to the antifungal activity of chitosan (CS) and to obtain a better natural bio-antimicrobial agent, CS was modified with acrylpimaric acid (APA). The grafting sites of APA on CS were controlled by adjusting the reaction time and the ratio of reactants to obtain APA grafted with CS C 2 -NH 2 (NCSAA) and C 6 -OH (CSAA). Intermediates to protect C 2 -NH 2 (PMCSAA) and final sample derivatives (PCSAA) were prepared using phthalic anhydride. The structural and crystal variations of the four derivatives were analyzed and determined by FTIR, 1 H NMR and XRD. The in vitro antifungal activities of the four modified samples against V. mali, C. lunata, A. solani, F. oxysporum f. sp. niveum, and F. graminearum were evaluated by the mycelial growth rate method, and PCSAA was screened for optimal inhibitory effect on V. mali with an EC 50 = 38.66 μg/mL. The SEM and TEM showed that these derivatives cause the loss of mycelial contents by disrupting the ultrastructure of the mycelium, destroying the internal structure of the mycelium, and preventing the cells from carrying out their normal life activities. In vivo experiments showed better curative effect (79.09 % ± 2.00) and protective effect (80.93 % ± 0.03) of PCSAA at 200 μg/mL.
研究领域:
微生物学
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植物病理学
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药剂学
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产品关联
DOI
PubMed
高影响因子
PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY
·
2024
·
IF 4.2
Yanting He,Hua Wang,Weimin Ma,Chengyu Gao,Runze Tian,Xiaozhou Su,Hao Feng,Lili Huang
Apple Valsa canker (AVC), primarily caused by the pathogenic fungus Valsa mali , is a devastating disease of apple. The development and application of high efficiency and low toxicity fungicides are of great significance for disease control. Natural active substances serve as a vital foundation for the development of novel green fungicides. In previous studies, the endophytic fungus Aa-Lcht was confirmed to contain specific inhibitory effect against V. mali . This study confirmed that Aa-Lcht fermentation broth (FB)’s suppression of V. mali growth and conidial germination, exhibiting AVC prevention. Through extraction, isolation, and purification, one active substance with high inhibitory effect on V. mali was obtained and identified as altenusin. Its concentration value for 50 % of maximal effect (EC 50 values) against V. mali mycelium growth was 3.118 μg/mL. Before V. mali infection, the lesion length of apple twigs and lesion area of fruits pretreated with altenusin decreased by 47.27 % and 80.52 %, respectively. Further research revealed that the hyphae of V. mali treated with altenusin exhibited irregular thickening of cell walls, severe vacuolation within the cells, and protoplasmic exudation. Meanwhile, transcriptome analysis indicated that altenusin primarily inhibited V. mali by interfering with the normal hyphal cell metabolism, substance degradation, peptidase activity, and proteolysis functions. Additionally, altenusin could also significantly up-regulate the expression of immunity resistance-related genes MdCYP81F2 , MdPR2 , MdPR4 , and MdPR5 in apple. Summarizing the above, the altenusin provides valuable insights for the development of novel green fungicides for controlling AVC disease, contributing to the safe and healthy development of apple production.
研究领域:
植物病理学
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农药科学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY
·
2018
·
IF 3.44
Yong Wang,Yang Sun,Zi Xiong,Kai He,Juntao Feng,Xing Zhang
In the current study, baseline sensitivity of Valsa mali to propamidine was determined using 80 strains collected from apple orchards in Shaanxi Province, China. The median effective concentration (EC 50 ) values for propamidine inhibiting mycelial growth ranged from 0.086 to 0.852 μg/mL, with a mean of 0.405 ± 0.137 μg/mL. After treated with propamidine, mycelia were contorted with an increased number of branches, loss of fruiting body production, and decreased cell membrane permeability . Moreover, the enzyme activities of the complexes I, II, IV and ATPase in the mitochondrial respiratory chain were increased significantly, while the enzyme activities of complexes III decreased. Importantly, both on detached leaves and branches of apple trees, propamidine applied at 100 μg/mL exhibited over 75% protective and curative efficacies, which were even better than the efficacies obtained by carbendazim at the same concentration. These results indicated that propamidine could be used as an alternative compound in controlling Valsa canker and mitochondrial respiratory chains might be correlated with the action mode of propamidine. This study encourages further investigation for the action mechanism of propamidine against plant pathogens and the information could be valuable for synthesis of new antifungal drugs with novel modes of action.
研究领域:
植物病理学
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真菌生物化学
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农药科学
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抗真菌剂
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农业真菌学
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DOI
高影响因子
Plants-Basel
·
2025
·Vol. 14
·期 1
·120
·
IF 4.1
Fangjie Li,Chen Yang,Maoye Li,Su Liu,Kuo Xu,Xianjun Fu
Valsa mali(V. mali) is a necrotrophic fungus responsible for apple Valsa canker, which significantly diminishes apple production yields and quality in China. Our serendipitous findings revealed that genistein significantly inhibits the mycelial growth ofV. mali, with an inhibition rate reaching 42.36 ± 3.22% at a concentration of 10 µg/mL. Scanning electron microscopy analysis revealed that genistein caused significant changes in the structure ofV. mali, including mycelial contraction, distortion, deformity, collapse, and irregular protrusions. Transmission electron microscopy analysis revealed leakage of cellular contents, blurred cell walls, ruptured membranes, and organelle abnormalities. Genistein has been shown to increase reactive oxygen species levels inV. malimycelia, as demonstrated by 2′,7′-dichlorofluorescin diacetate staining. This increase was associated with a decrease in superoxide dismutase activity alongside increases in catalase and peroxidase activities. These changes collectively disrupted the oxidative equilibrium, leading to the induction of oxidative stress. The transcriptomic analysis revealed 13 genes enriched in this process, linked to unsaturated fatty acid biosynthesis (three downregulated DEGs), saturated fatty acid biosynthesis (three upregulated and six downregulated DEGs), and fatty acid metabolism (four upregulated and nine downregulated DEGs). Additionally, the downregulated DEGs VMIG_07417 and VMIG_08675, which are linked to ergosterol biosynthesis, indicate possible changes in membrane composition. In conjunction with the qRT-PCR results, it is hypothesized that genistein exerts an antifungal effect onV. malithrough ROS-mediated lipid peroxidation. This finding has the potential to contribute to the development of novel biological control agents for industrial crops.
研究领域:
植物病理学
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真菌学
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植物病原学
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生物技术
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农业科学
✓ 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）