BIODEGRADATION
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2020
·Vol. 31
·期 4
·275-288
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IF 2.805
Wang Yuanshan,Gong Meihua,Wang Xianlin,Peng Xiaolun,Wang Yuwei,Guan Jiahui,Cheng Dongyuan,Weng Chunyue,Zheng Yuguo
Ivermectin (IVM) is a widely used antiparasitic agent and acaricide. Despite its high efficiency against nematodes and arthropods, IVM may pose a threat to the environment due to its ecotoxcity. In this study, degradation of IVM by a newly isolated bacterium Aeromonas taiwanensis ZJB-18,044 was investigated. Strain ZJB-18,044 can completely degrade 50 mg/L IVM in 5 d with a biodegradation ability of 0.42 mg/L/h. Meanwhile, it exhibited high tolerance (50 mg/L) to doramectin, emamectin, rifampicin, and spiramycin. It can also efficiently degrade doramectin, emamectin, and spiramycin. The IVM degradation of strain ZJB-18,044 can be inhibited by erythromycin, azithromycin, spiramycin or rifampicin. However, supplement of carbonyl cyanide m -chlorophenylhydrazone, an uncoupler of oxidative phosphorylation, can partially recover the IVM degradation. Moreover, strain ZJB-18,044 cells can pump out excess IVM to maintain a low intracellular IVM concentration. Therefore, the IVM tolerance of strain ZJB-18,044 may be due to the regulation of the intracellular IVM concentration by the activated macrolide efflux pump(s). With the high IVM degradation efficiency, A. taiwanensis ZJB-18,044 may serve as a bioremediation agent for IVM and other macrolides in the environment.
研究领域:
环境科学
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微生物学
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生物修复
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Nan Wang,Chi Zhang,Houxier Li,Jiahui Wu,Dachuan Zhang,Yan Li,Li Yang,Nan Zhang,Xueyong Wang
This study investigated the in vitro fermentation characteristics of different structural types of Canna edulis resistant starch (RS). RS3 was prepared through a double enzyme hydrolysis method, and RS4 (OS-starch and cross-linked starch) was prepared using octenyl succinic anhydride and sodium trimetaphosphate/sodium tripolyphosphate, respectively. The RS3 and RS4 samples were structurally analyzed using scanning electron microscopy, Fourier-transform infrared spectroscopy, differential scanning calorimetry, and X-ray diffraction analysis. This was followed by in vitro fermentation experiments. The results revealed microstructure differences in the two groups of starch samples. Compared to native starch, RS3 and RS4 exhibited a lower degree of order and endothermic energy, with lower crystallinity (RS3: 29.59 ± 1.11 %; RS4 [OS-starch]: 28.01 ± 1.32 %; RS4 [cross-linked starch]: 30.44 ± 1.73 %) than that in native starch (36.29 ± 0.89 %). The RS content was higher in RS3 (63.40 ± 2.85 %) and RS4 (OS-starch: 71.21 ± 1.28 %; cross-linked starch: 74.33 ± 0.643 %) than in native starch (57.71 ± 2.95 %). RS3 and RS4 exhibited slow fermentation rates, promoting the production of short-chain fatty acids. RS3 and cross-linked starch significantly increased the production of acetate and butyrate. Moreover, RS3 significantly promoted the abundance of Lactobacillus , while OS-starch and cross-linked starch significantly enhanced the abundance of Dorea and Coprococcus , respectively. Hence, the morphological structure and RS content of the samples greatly influenced the fermentation rate. Moreover, the different varieties of RS induced specific gut microbial regulation. Hence, they show potential applications in functional foods for tailored gut microbiota management.
研究领域:
食品科学
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微生物学
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营养学
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生物技术
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Tong Zhao,Sining Liu,Yutong Shuai,Xinyi Zhang,Min Chen,Sijie Pei,Yuxi Duan,Shukai Wang,Yu Lu,Zhongfu Wang,Guiping Gong,Linjuan Huang
Pectin is a structurally complex heteropolysaccharide that affects intestinal microorganisms and mucin O -glycans. The present study employed an in vitro model to investigate dynamic changes in microbiota during pectin fermentation. Residual pectin fragments arising from its fermentation were applied to HT29-MTX cells to study the effect of pectin structure on mucin O -glycosylation. Prevotella , Bacteroides , and Parabacteroides were found to preferentially degrade galactose, arabinose, and on the rhamnogalacturonan RG-I side chain region and methyl esterification groups of pectin. Bifidobacterium , Enterococcus , Megamonas , and Dorea metabolized the galacturonic HG region on pectin to produce butyrate. All pectin fragments were found to up-regulate total O -glycans (1.55–2.73 fold) and neutral O -glycans (1.11–1.49 fold) on HT29-MTX mucins. The large HG fragment (81.04 kDa) increased significantly the amount of non-fucosylated glycans (by 2.46-fold); whereas the small HG fragment (16.02 kDa) promoted fucosylated (by 9.25 fold), and especially di-fucosylated O -glycans. Collectively, these results demonstrate that gut microorganisms degrade pectin fragments in the following order of utilization: RG-I, RG-II, and HG. The small fragment of HG improves the expression of fucosylated O -glycans in HT29-MTX cells, mainly owing to an increase in di-fucosylated O -glycans.
研究领域:
微生物学
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胃肠病学
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细胞生物学
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营养科学
✓ 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）