JOURNAL OF CHROMATOGRAPHIC SCIENCE
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2022
·
IF 1.555
Zhang Jing,Yang Junqing,Luo Ying,Li Jiansha,Gong Tao,Huang Suqiong,Xiong Yan,Jiang Xinhui
Using 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate as a pre-column derivatization reagent, optimized derivatization and chromatography parameters, a simple high-performance liquid chromatography fluorescence detector (HPLC–FLD) method was developed and validated to determine 23 related amines in plasma and cortex of C57BL/6 mice with cerebral ischemia–reperfusion injury. The prepared samples were separated on a ZORBAX SB-C18 column (4.6 mm × 250 mm, 5 μm) with 60% acetonitrile (ACN) and 20 mM sodium acetate solution (pH adjusted to 5.0 by phosphoric acid). All analytes achieved good separation within 1.2 h at a flow rate of 1 mL/min. The limits of detection and limits of detection quantitation of the method were ranged from (0.1–9.2) to (0.3–30.6) ng/mL, respectively. The analytical method was apt for simultaneously determining 23 amino acids in plasma and cortex. Our results revealed that the relevant amino acids were significantly altered (P < 0.05) in C57BL/6 mice.
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PubMed
高影响因子
BIOMEDICAL CHROMATOGRAPHY
·
2022
·Vol. 36
·期 10
·e5435
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IF 1.911
Jing Zhang,Jun-qing Yang,Ying Luo,Jian-sha Li,Tao Gong,Su-qiong Huang,Yan Xiong,Xin-hui Jiang
The study of brain diseases has long been of interest to researchers worldwide, and stroke is the third leading cause of death that threatens human health. At the same time, cerebral ischemia–reperfusion injury is closely associated with high rates of disability and mortality. The conditions of the 6-aminoquinolyl N -hydroxysccinimidyl carbamate method for the derivatization of amino acids in the bone marrow fluid and hippocampus of C57BL/6 mice with cerebral ischemia–reperfusion injury were explored and optimized, such as the column temperature, concentration of derivatization reagents and mobile phase concentration. The mobile phase consisted of 20 m m sodium acetate solution (phosphoric acid to adjust pH 5.0) and 60% acetonitrile solution at a flow rate of 1 ml min −1 . The 23 analytes were separated and determined in a gradient elution procedure; the correlation coefficient r was >0.9990 in the range 0.1–8.0 μg ml −1 . The results showed that the content of relevant analytes was significantly changed in the cerebral ischemia–reperfusion injury model, and the method was suitable for the simultaneous determination of 23 amino acids in the bone marrow fluid and hippocampus of C57BL/6 mice.
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BIORESOURCE TECHNOLOGY
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2021
·
IF 9.642
Yu Zhang,Minhua Wei,Guihong Zhao,Wenjie Zhang,Yingzi Li,Beibei Lin,Yanjun Li,Qingyang Xu,Ning Chen,Chenglin Zhang
l -Homoserine is a valuable non-proteinogenic amino acid used in the synthesis of various important compounds. Microbial fermentation has potential value for producing l -homoserine on a large scale, but suffers from a low yield and the need for expensive additives. In this study, a non-induced, non-auxotrophic, plasmid-free Escherichia coli chassis for the high-efficiency production of l -homoserine was constructed. Initially, the l -homoserine degradation pathway was dynamically attenuated. Subsequently, systems metabolic engineering strategies were employed, including reinforcing the synthetic flux, improving NADPH generation, and elevating l -homoserine efflux. The constructed strain HOM-14, produced 60.1 g/L l -homoserine without additional supplements or inducers, which achieved the highest fermentative production efficiency of l -homoserine till date. Moreover, common byproducts, such as acetate, did not accumulate. The strategies presented here can be applied in the further engineering of chassis for the scale-up production of l -homoserine and derivatives.
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高影响因子
Frontiers in Pharmacology
·
2019
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IF 3.845
Wei Xia,Zhu Qingfen,Liu Na,Xu Lihua,Wei Sheng,Fan Zhiyun,Sun Changhua,Zhao Yan,Qiao Mingqi,Wu Jibiao,Hu Defu,Wang Yang,Sun Peng
Zhenlong Xingnao Capsule (ZXC) is a Tibetan medicine used to treat ischemic stroke. In this study, we determined the in vitro and in vivo effects of ZXC on reactive oxygen species (ROS) in a mouse BV-2 microglial cell hypoxia-reoxygenation and rat middle cerebral artery occlusion infarction models. We aimed to clarify the role of ZXC in cerebral ischemia protection; reveal amino acid neurotransmitter changes in the frontal cortex after drug intervention; determine mRNA and protein expression changes in Bcl-2, Bax, caspase-3, P38, and nuclear factor (NF)-кB in the frontal cortex and changes in antioxidant indices in the brain; and elucidate the mechanisms underlying ZXC action. After hypoxia-reoxygenation, ROS levels were significantly increased in BV-2 cells, and their levels decreased after treatment with ZXC. ZXC had protective effects on ischemic/anoxic injury in vitro and in vivo by downregulating the expressions of caspase-3 and NF-кB mRNA during ischemia and reperfusion and that of p38 and caspase-3 during acute ischemia and reperfusion as well as the steady-state levels of excitatory amino acids/inhibitory amino acids and by improving the total antioxidant capacity and total superoxide dismutase activities during ischemia. These findings provide new molecular evidence for the mechanisms underlying ZXC action.
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高影响因子
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