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Effect of acute alcoholism on hepatic enzymes and oxidation/antioxidation in rats 被引量:3
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作者 You-Ming Li, Shao-Hua Chen, Chao-Hui Yu, Yu Zhang and Gen-Yun Xu Hangzhou, China Department of Digestive Medicine, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003 . Chi- na 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2004年第2期241-244,共4页
BACKGROUND: Around the world more and more people suffer from acute alcoholism. The purpose of this study was to determine hepatic enzymes and oxidation/antioxidation in rats with acute alcoholism. METHODS: Rats were ... BACKGROUND: Around the world more and more people suffer from acute alcoholism. The purpose of this study was to determine hepatic enzymes and oxidation/antioxidation in rats with acute alcoholism. METHODS: Rats were randomly divided into three groups; control, low-dose alcohol, and high-dose alcohol. Each al- cohol group ( n = 12) was intravenously infused with etha- nol at a dose of 0.3 or 0.7 g/kg body weight respectively. The control group (n =11) was intravenously infused with normal saline at a dose of 0.5 g/kg body weight. Blood was collected for detection of hepatic enzymes and index of oxidation/antioxidation. RESULTS: The ratio of AST to ALT was 2.44±0.46, 2.57± 0.60 and 3.03 ±0.46 in the three groups, and the difference was significant between the control and high-dose alcohol groups (P^0.05). No significant changes were observed in the levels of serum alanine aminotransferase (ALT), aspar- tate aminotransferase (AST), total protein (Tp), albumin (Alb), alkaline phosphatase (ALP), cholinesterase (ChE), total bilirubin (TB), C-reactive protein (CRP) and amy- lase. The levels of serum nitric oxide (NO) in the 3 groups were 39.2 ±73.25 mol/L, 42.30 ±4.60 mol/L and 47.86± 4.66 mol/L, and significant difference was seen between the control group and the high-dose alcohol group (P < 0.01). No significant difference was found in the levels of serum superoxide dismutase (SOD), glutathione (GSH), malondiethylaldehyde (MDA), and CRP in the 3 groups. CONCLUSION: The ratio of AST to ALT appears to be a useful index for acute alcohol intoxication. NO is involved in the mechanism of acute alcohol intoxication. 展开更多
关键词 ALCOHOLISM INFUSION nitric oxide oxidation/antioxidation animal model hepatic enzyme
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Marine fungal metabolite butyrolactone Ⅰ improves Aβ_(1-42)-induced cognitive impairment in mice via gut-brain axial microbiota remodeling,anti-inflammation,and antioxidation
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作者 Fuyan YANG Longjian ZHOU +5 位作者 Jiahang DENG Yuan WANG Zhiyou YANG Yongping ZHANG Yayue LIU Yi ZHANG 《Journal of Oceanology and Limnology》 2026年第1期386-405,共20页
Alzheimer’s disease(AD)is a complex neurodegenerative disorder associated with changes in inflammation,oxidative stress,and gut microbiota composition.Butyrolactone Ⅰ(BTL-Ⅰ),a fungal metabolite,has shown anti-infla... Alzheimer’s disease(AD)is a complex neurodegenerative disorder associated with changes in inflammation,oxidative stress,and gut microbiota composition.Butyrolactone Ⅰ(BTL-Ⅰ),a fungal metabolite,has shown anti-inflammatory,microbiota regulating,and memory-improving potentials in previous in vitro and AlCl3-induced zebrafish studies.However,its effects of memory-improving and gutbrain axis regulating on Aβ-induced mammalian AD models have not been explored.In this study,intragastric administrated BTL-Ⅰ ameliorated cognitive deficits related to recognition and spatial memory impaired by Aβ_(1-42)intracerebroventricular injection in mice.BTL-Ⅰ maintained gut microbiota balance by increasing the abundance of Blautia,Muribaculaceae,Bacteroides,Akkermansia,etc.,and decreasing CAG-352,Clostridia UCG-014,different Lachnospiraceae groups,etc.,and Firmicutes/Bacteroidota ratio and elevated the levels of short-chain fatty acids.Additionally,it alleviated intestinal oxidative stress,inflammatory responses,and pathological damage.Furthermore,BTL-I reversed Aβ_(1-42)-induced activation of microglia and astrocytes in the hippocampus and inhibited the elevated oxidative stress and proinflammatory cytokines in both plasma and brain.The correlation analysis between the regulated taxa and biomarkers supports the role of gut microbiota in adjusting inflammation,oxidative stress,and memory.In conclusion,BTL-I may serve as a valuable drug lead for treating Alzheimer’s disease by systematically inhibiting microbiota imbalance,inflammation,and oxidative stress along the gut-brain axis. 展开更多
关键词 Alzheimer’s disease butyrolactoneⅠ cognitive deficit microbiota composition oxidative stress NEUROINFLAMMATION
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Hypidone hydrochloride(YL-0919)ameliorates functional deficits after traumatic brain injury in mice by activating the sigma-1 receptor for antioxidation 被引量:2
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作者 Yafan Bai Hui Ma +5 位作者 Yue Zhang Jinfeng Li Xiaojuan Hou Yixin Yang Guyan Wang Yunfeng Li 《Neural Regeneration Research》 SCIE CAS 2025年第8期2325-2336,共12页
Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary injury.In this study,we evaluated hypidone hydrochloride(YL-0... Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary injury.In this study,we evaluated hypidone hydrochloride(YL-0919),a self-developed antidepressant with selective sigma-1 receptor agonist properties,and its associated mechanisms and targets in traumatic brain injury.Behavioral experiments to assess functional deficits were followed by assessment of neuronal damage through histological analyses and examination of blood-brain barrier permeability and brain edema.Next,we investigated the antioxidative effects of YL-0919 by assessing the levels of traditional markers of oxidative stress in vivo in mice and in vitro in HT22 cells.Finally,the targeted action of YL-0919 was verified by employing a sigma-1 receptor antagonist(BD-1047).Our findings demonstrated that YL-0919 markedly improved deficits in motor function and spatial cognition on day 3 post traumatic brain injury,while also decreasing neuronal mortality and reversing blood-brain barrier disruption and brain edema.Furthermore,YL-0919 effectively combated oxidative stress both in vivo and in vitro.The protective effects of YL-0919 were partially inhibited by BD-1047.These results indicated that YL-0919 relieved impairments in motor and spatial cognition by restraining oxidative stress,a neuroprotective effect that was partially reversed by the sigma-1 receptor antagonist BD-1047.YL-0919 may have potential as a new treatment for traumatic brain injury. 展开更多
关键词 antidepressant drug blood-brain barrier cognitive function hypidone hydrochloride(YL-0919) neurological function nuclear factor-erythroid 2 related factor 2 oxidative stress sigma-1 receptor superoxide dismutase traumatic brain injury
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Oxidation behavior of Ti55 alloy and TiBw/Ti55 composites and antioxidation mechanism of TiBw in composites at 960–1000℃
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作者 Guangyu Liu Lian Li Miaoquan Li 《Journal of Materials Science & Technology》 2025年第10期55-68,共14页
The oxidation behavior of Ti55 alloy and TiBw/Ti55 composites at temperatures ranging from 960 to 1000℃ was investigated by characterizing the surface and cross-section microstructure of specimens.Results showed that... The oxidation behavior of Ti55 alloy and TiBw/Ti55 composites at temperatures ranging from 960 to 1000℃ was investigated by characterizing the surface and cross-section microstructure of specimens.Results showed that TiBw reinforcement accelerated the occurrence of Ti_(6O)/Ti_(3O) by dissolving oxygen in titanium in the starting oxidation stage,and the Ti_(6O)/Ti_(3O) transformed into TiO_(2) with the progression of oxidation.Meanwhile,TiBw reinforcement promoted the formation of(101)crystal planes to be beneficial to the growth of TiO_(2) twins.The cross-sectional characterization showed that the oxide layer of Ti55 alloy and TiBw/Ti55 composites from outside to inside was TiO_(2)+Al_(2)O_(3),TiO_(2),Ti-Sn compounds,Ti_(6O)/Ti_(3O) in sequence,which was confirmed by calculating the standard Gibbs free energy of the oxide nucleation.The TiBw reinforcement accelerated the occurrence of suboxides Ti_(6O)/Ti_(3O) by dissolving oxygen in titanium,and promoted the formation of(101)crystal planes which were beneficial to the growth of TiO_(2) twins.The optimal addition of TiBw induced the TiO_(2) twins,promoted the random orientation of oxides and refined the oxide size of the TiBw/Ti55 composites with 3.5%volume fractions of TiBw,resulting in the best resistance against oxidation. 展开更多
关键词 Titanium alloy Titanium matrix composite TiBw oxidation behavior oxidE TWIN
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Phytochemicals, Antioxidation, and Heat Stability of Aqueous Extracts from Cherry (Prunus serrulata) Petals
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作者 Sy-Yu Shiau Shuting Ni +2 位作者 Yanli Yu Songling Cai Wenbo Huang 《Phyton-International Journal of Experimental Botany》 2025年第10期3047-3060,共14页
Consumers are increasingly demanding natural colorants that are safe and offer health benefits.In addition to their ornamental characteristics,Kanzan cherry(KC)blossoms present a promising source of red-hued natural c... Consumers are increasingly demanding natural colorants that are safe and offer health benefits.In addition to their ornamental characteristics,Kanzan cherry(KC)blossoms present a promising source of red-hued natural colorants and functional bioactive substances.This research utilized distilled water to extract KC petals(KCP)and their ground powders(KCPP)under varying temperatures(30℃–90℃)and times(30–180 min).The total monomeric anthocyanins(TMAC)and total phenolics(TPC)in the extracts were evaluated via the pH differential and Folin–Ciocalteu methods.Antioxidant capacities were assessed by DPPH free radical scavenging ability and reducing power.Results indicated that the optimal extraction of TMAC and TPC from KCP occurred at 90℃ for 30 min,and the resulting extracts exhibited the highest antioxidant activities among all tested temperatures and durations.Compared to different particle sizes,the finest KCPP generally produced extracts with the highest TMAC,TPC,and antioxidant activity,due to enhanced mass and heat transfer.When compared with the acidified alcohol method,hot water extraction resulted in 68.23%and 71.41%TMAC yields for petals and powders,respectively,while TPC levels were similar or higher.TMAC or TPC showed a significantly positive correlation(p<0.01)with the antioxidant activities.These findings demonstrate that hot water extraction is a viable and environmentally friendly alternative for phytochemical recovery from KC.Additionally,elevated extraction temperature and pH accelerated anthocyanin degradation and shortened its half-life,while higher pH also lowered the activation energy,enthalpy,entropy,and Gibbs free energy.Thus,red–orange KC extracts with rich bioactivity may serve as promising ingredients for functional foods having acidic pH levels. 展开更多
关键词 Cherry blossom extraction ANTHOCYANIN phenolics antioxidant kinetics thermodynamics
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Corrosion Behavior,Antioxidation Property,Antibacterial Ability,and Osteogenic Activity of Zn/Chitosan-Catechol Coating Prepared on NiTi Alloy
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作者 Shuaiwu Peng Zejun Chen +5 位作者 Runhua Yao Sen Pei Ruiqiang Hang Yonghua Sun Xiaohong Yao Ying Lu 《Acta Metallurgica Sinica(English Letters)》 2025年第11期1909-1925,共17页
NiTi alloy has been widely used as orthopedic implant materials due to its unique shape memory properties and superelasticity.However,implantation failure often occurs because of the poor antibacterial ability,antioxi... NiTi alloy has been widely used as orthopedic implant materials due to its unique shape memory properties and superelasticity.However,implantation failure often occurs because of the poor antibacterial ability,antioxidation property and corrosion resistance of the NiTi alloy.In order to overcome the above problems,we constructed Zn/polydopamine(PDA)/Chitosan-Catechol(CS-C)composite coating on the surface of NiTi alloy in this paper.The surface morphology and wettability of the coating were characterized by scanning electron microscopy(SEM)and optical contact angle measuring instrument,respectively.The results showed that the Zn/CS-C coating was successfully prepared,and exhibited good hydrophilic property,especially the sample Zn/PDA/CS-C-24 h.In addition,the corrosion resistance,antioxidation property and biological properties of the coating were systematically analyzed.The results indicated that the Zn/PDA/CS-C composite coating exhibited good corrosion resistance and antibacterial property,antioxidant property and osteogenic activity,especially sample Zn/PDA/CS-C-24 h.The sample Zn/PDA/CS-C-24 h could effectively protect osteoblasts from reactive oxygen species(ROS)damage and promote cell proliferation and osteoblast differentiation.This study provides a feasible and effective strategy for the surface modification of orthopedic implant. 展开更多
关键词 NiTi alloy Chitosan-catechol Corrosion behavior antioxidation property Antibacterial ability Osteogenic activity
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Study on Antioxidation Effect of Polyphenols from Pomegranate Peel in Vivo 被引量:2
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作者 傅力 徐佳 +2 位作者 包晓玮 赵晓梅 叶凯 《Agricultural Science & Technology》 CAS 2016年第1期164-167,共4页
[Objective] The aim was to study the antioxidant effect of polyphenols from pomegranate peel in vivo. [Method] The Kunming rats were randomly divided into a control group, a low-dose group, a middle-dose group and a h... [Objective] The aim was to study the antioxidant effect of polyphenols from pomegranate peel in vivo. [Method] The Kunming rats were randomly divided into a control group, a low-dose group, a middle-dose group and a high-dose group,n=10; the protein content, the activities of the superoxide dismutase(SOD) and the glutathione peroxidase(GSH-PX), the content of the maleic dialdehyde(MDA) in serum and liver tissue of the rats from different groups were determined. [Result]The polyphenols of pomegranate peel could increase protein content, activities of superoxide dismutase(SOD) and glutathione peroxidase(GSH-PX) in serum and liver tissue, and decrease the maleic dialdehyde(MDA) content simultaneously. [Conclusion] Polyphenols of pomegranate peel have strong antioxidant activity in vivo. 展开更多
关键词 Pomegranate peel POLYPHENOLS antioxidation In vivo
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Comparisons between Phenolic Compounds and Antioxidation of Momordica charantia L. in Different Varieties 被引量:1
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作者 黄龙 邓媛元 +4 位作者 张名位 张雁 魏振承 张瑞芬 唐小俊 《Agricultural Science & Technology》 CAS 2012年第6期1263-1269,共7页
[Objective] The aim was to compare contents of free and bound polyphenol and antioxidation of balsam pear in different varieties. [Method] Fourteen varieties of balsam pear were chosen to analyze total contents of fre... [Objective] The aim was to compare contents of free and bound polyphenol and antioxidation of balsam pear in different varieties. [Method] Fourteen varieties of balsam pear were chosen to analyze total contents of free or bound phenol and components of free phenol. FRAP (Freeic reducing/antioxidant power), DPPH (1,1diphenyl-2-picrylhydrazy), and ABTS +· (2, 2’-azinobis-3-ethylbenzothiazoline-6-sulphonic acid diammonium salt) were used to measure antioxidation and analyze relationship between polyphenol content and antioxidation. [Result] Among the fourteen varieties of balsam pear, free, bound and total phenols were 157.58 -382.92, 6.46 -54 and 175.27 -413.79 mg GAE/100 g DW; coefficients of variance were 23.50% , 61.04% and 21.58%, respectively; free phenol accounted for 91.34% of total phenol and bound phenol accounted for 8.66% ; contents of total flavone for the fourteen varieties were from 8.97 to 18.22 mg CE/100 g DW and the coefficient was at 22.80%; vanillic aldehyde acid, epicatechin and rutin differed in contents among different varieties, which changed in 1.83-9.29, 35.17-114.52 and 0.91-4.53 mg/100 g DW and the coefficients were 43.85%, 26.97% and 33.09%; FRAP antioxidation was at 272.16 -713.32 mg TE/100 g DW and coefficient at 27.67% ; IC 50 of DPPH and ABTS +· clearance were 11.43-34.14 and 21.57-119.71 mg GAE/100 g DW and coefficients were at 35.10% and 63.75% , accordingly; content of total phenol was of extremely positive correlation with FRAP (P0.01) and of extremely negative correlation with IC 50 of DPPH and ABTS + · clearance (P0.01). [Conclusion] Contents of phenolic compounds and antioxidation are of significant genotype differences; and phenolic substance and antioxidation are mainly in free form and phenolic substance is the major basis for antioxidation. 展开更多
关键词 Momordica charantia L. Phenolic compounds antioxidation
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Effect of Substrate Micro-arc Oxidation Pretreatment on Microstructure and High-Temperature Oxidation Resistance of Si-Cr-Ti-Zr Coating on Ta12W Alloy
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作者 Yang Fan Chang Jianxiu +2 位作者 Wang Xin Li Hongzhan Yan Peng 《稀有金属材料与工程》 北大核心 2026年第1期92-104,共13页
To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretre... To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretreatment was employed to construct a Ta_(2)O_(5)ceramic layer on the Ta12W alloy surface.Subsequently,a slurry spraying-vacuum sintering method was used to prepare a Si-Cr-Ti-Zr coating on the pretreated substrate.Comparative studies were conducted on the microstructure,phase composition,and isothermal oxidation resistance(at 1600℃)of the as-prepared coatings with and without the micro-arc oxidation ceramic layer.The results show that the Ta_(2)O_(5)layer prepared at 400 V is more continuous and has smaller pores than that prepared at 350 V.After microarc oxidation pretreatment,the Si-Cr-Ti-Zr coating on Ta12W alloy consists of three distinct layers:an upper layer dominated by Ti_(5)Si_(3),Ta_(5)Si_(3),and ZrSi;a middle layer dominated by TaSi_(2);a coating/substrate interfacial reaction layer dominated by Ta_(5)Si_(3).Both the Si-Cr-Ti-Zr coatings with and without the Ta_(2)O_(5)ceramic layer do not fail after isothermal oxidation at 1600℃for 5 h.Notably,the addition of the Ta2O5 ceramic layer reduces the high-temperature oxidation rate of the coating. 展开更多
关键词 tantalum-tungsten alloy silicide coating micro-arc oxidation reaction formation mechanism high-temperature oxidation
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Recent advances in high-temperature oxidation behavior and underlying mechanisms of Mg-RE alloys:A comprehensive review
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作者 Yu Ma Yu Cao +4 位作者 Yulian Kuang Yajun Wang Yuhao Gong Bin Jiang Jonghyun Kim 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期446-466,共21页
The limited high-temperature oxidation resistance of Mg alloys is a key factor restricting their development and application.The addition of some rare earth elements(REs),owing to their unique physical and chemical pr... The limited high-temperature oxidation resistance of Mg alloys is a key factor restricting their development and application.The addition of some rare earth elements(REs),owing to their unique physical and chemical properties,can significantly enhance the oxidation resistance of Mg alloys.Based on our previous study,we conclude that REs such as Gd,Y,and Ce enhance the oxidation resistance of Mg-RE alloys.This article comprehensively reviews recent research progress on high-temperature oxidation behavior and the potential mechanism in Mg-RE alloys.Based on the thermodynamic and kinetic analyses,the evolution of the complex oxide system formed during the high-temperature oxidation of Mg-RE alloys is first summarized.The diffusion behavior and concentration control mechanisms of REs during the oxidation process and how these mechanisms affect the sustained growth of the oxide film and antioxidant properties were elucidated.Moreover,the different structures of the oxide films were classified,and their properties were discussed.Finally,this paper introduces the applications of commonly used REs in Mg alloys and frontier research on their oxidation mechanisms.Based on the above review,we propose that future research perspectives can be explored in terms of expanding the experimental temperature range for oxidation tests,optimizing the chemical composition by adding trace REs to study their synergistic mechanism,revealing the underlying oxidation mechanism through advanced in situ microscopic characterization methods,and investigating the mechanical properties of oxide films using diverse approaches. 展开更多
关键词 magnesium-rare earth element alloy high-temperature oxidation THERMODYNAMICS oxidation resistance oxide films
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Research Status and Prospects of Platinum Group Metal Coatings with High-Temperature Oxidation Resistance
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作者 Ding Chenxi Liu Zhongyu +3 位作者 Fang Zhen Wang Haoxu Lv Biao Hu Zhenfeng 《稀有金属材料与工程》 北大核心 2026年第2期333-344,共12页
Platinum group metals have high melting points,strong corrosion resistance,stable chemical properties,and low oxygen permeability in high-temperature oxygen-containing environments.As thermal protective coating materi... Platinum group metals have high melting points,strong corrosion resistance,stable chemical properties,and low oxygen permeability in high-temperature oxygen-containing environments.As thermal protective coating materials,they have gained essential applications in the aerospace field and have excellent prospects for application in frontier military fields,such as protecting hot-end components of hypersonic aircraft.This research reviewed the latest research progress of platinum group metal coatings with hightemperature oxidation resistance,including coating preparation techniques,oxidation failure,and alloying modification.The leading preparation techniques of current platinum group metal coatings were discussed,as well as the advantages and disadvantages of various existing preparation techniques.Besides,the intrinsic properties,failure forms,and failure mechanisms of coatings of single platinum group metal in high-temperature oxygen-containing environments were analyzed.On this basis,the necessity,main methods,and main achievements of alloying modification of platinum group metals were summarized.Finally,the future development of platinum group coatings with high-temperature oxidation resistance was discussed and prospected. 展开更多
关键词 platinum group metal coatings preparation technique high temperature oxidation resistance alloying modification
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Study on the Extraction of Flavonoids from Hylocereus undatus(Haw.)Britton&Rose and Their Antioxidant Activity
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作者 Zhao LIU Deyun MA +1 位作者 Rimeng CHEN Meijiao MO 《Agricultural Biotechnology》 2026年第1期65-69,共5页
[Objectives]This study was conducted to investigate the extraction process,content determination,and antioxidant properties of flavonoids from Hylocereus undatus(Haw.)Britton&Rose.[Methods]Using H.undatus as the r... [Objectives]This study was conducted to investigate the extraction process,content determination,and antioxidant properties of flavonoids from Hylocereus undatus(Haw.)Britton&Rose.[Methods]Using H.undatus as the raw material,the effects of ethanol concentration,ultrasonic temperature,time,and solid-to-liquid ratio on the total flavonoid yield were investigated through single-factor and orthogonal experiments.[Results]All factors had a significant effect on the yield.The optimized conditions were determined as follows:ethanol concentration 75%,ultrasonic temperature 60℃,ultrasonic time 30 min,and solid-to-liquid ratio 1:50(g/ml).Under these conditions,the total flavonoid yield reached 3.08%.Evaluation of antioxidant activity revealed that the extract exhibited superior scavenging rates against both DPPH and hydroxyl radicals compared with the standard reference compound BHT.[Conclusions]This study holds significant importance for elucidating the pharmacological mechanisms of flavonoids in H.undatus and for expanding their application in medicine and health products. 展开更多
关键词 Hylocereus undatus FLAVONOIDS antioxidant activity
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Evaluation of in vitro Antibacterial,Antioxidant,andα-Glucosidase Inhibitory Effects of Pilea peltata Hance
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作者 Zhiying WEI Junqi LI +4 位作者 Xiaojiao PAN Fangchan LI Yaheng QIU Jiao JIANG Xuehuan CAO 《Medicinal Plant》 2026年第1期20-23,29,共5页
[Objectives]To evaluate the in vitro antibacterial,antioxidant,andα-glucosidase inhibitory activities of the ethanol total extract and four different polarity fractions(n-butanol,ethyl acetate,petroleum ether,and wat... [Objectives]To evaluate the in vitro antibacterial,antioxidant,andα-glucosidase inhibitory activities of the ethanol total extract and four different polarity fractions(n-butanol,ethyl acetate,petroleum ether,and water)of Pilea peltata Hance,so as to provide a reference for its further development and research.[Methods]The antibacterial activity of P.peltata was evaluated in vitro by determining the minimum inhibitory concentration(MIC)and minimum bactericidal concentration(MBC)of its ethanol total extract and four different polarity fractions against seven test bacterial strains using the broth microdilution method.The in vitro antioxidant activity was investigated through DPPH radical,hydroxyl radical,and superoxide anion radical scavenging assays,with vitamin C(Vit C)as the positive control and the half maximal scavenging concentration(IC 50)as the evaluation indicator.The in vitroα-glucosidase inhibitory activity was assessed by measuring the peak area of p-nitrophenol(PNP),the hydrolysis product of 4-nitrophenylα-D-glucopyranoside(PNPG),via high-performance liquid chromatography(HPLC),using the half maximal inhibitory concentration(IC 50)as the evaluation indicator.[Results]Both the ethanol total extract and the four different polarity fractions of P.peltata exhibited significant in vitro anti-Streptococcus pneumoniae activity.The DPPH radical scavenging capacities of the ethanol total extract and the various fractions were all weaker than that of VitC,with the order of efficacy being:n-butanol fraction>ethanol total extract>ethyl acetate fraction>petroleum ether fraction>aqueous fraction.For hydroxyl radical scavenging activity,the efficacy order of P.peltata fractions was:n-butanol extract>ethyl acetate extract>ethanol total extract>petroleum ether extract>aqueous extract.Notably,the n-butanol fraction(IC 50=0.068±0.001)demonstrated stronger activity than VitC(IC 50=0.097±0.001).The activity of the ethyl acetate fraction(IC 50=0.096±0.004)was comparable to that of VitC(IC 50=0.097±0.001).The superoxide anion scavenging capacities of the ethanol total extract and different polarity fractions from P.peltata were all weaker than that of VitC,with the order of efficacy being:n-butanol fraction>ethyl acetate fraction>ethanol total extract>petroleum ether fraction>aqueous fraction.The ethanol total extract and aqueous fraction of Pilea peltata showed no significant in vitroα-glucosidase inhibitory activity.Compared with the acarbose group,the IC 50 values of the ethyl acetate fraction and the n-butanol fraction both showed highly significant differences(P<0.01).[Conclusions]This study provides an experimental basis for the pharmacodynamic study and active component study of P.peltata. 展开更多
关键词 Pilea peltata Hance ANTIBACTERIAL antioxidation α-glucosidase inhibition
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Comprehensive review of the pharmacological potential of Passiflora incarnata L.:neuropsychiatric,antioxidant,antimicrobial,and anticancer activities
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作者 Balasubramanian Deepika Koyeli Girigoswami 《Traditional Medicine Research》 2026年第4期11-26,共16页
Passiflora incarnata L.,commonly known as passionflower,is traditionally cultivated as an ornamental plant but has demonstrated diverse therapeutic potential.Its pharmacological effects are attributed to bioactive com... Passiflora incarnata L.,commonly known as passionflower,is traditionally cultivated as an ornamental plant but has demonstrated diverse therapeutic potential.Its pharmacological effects are attributed to bioactive compounds such as flavonoids and alkaloids,which influence multiple biological pathways.This review aims to summarise and critically analyse recent findings on the pharmacological properties of Passiflora incarnata L.,focusing on its neuropsychiatric,antioxidant,antimicrobial,and anticancer activities.A targeted literature search was conducted in PubMed,Scopus,Web of Science,and Google Scholar for peer-reviewed publications between 2000 to 2025.Relevant articles were screened,and a more appropriate article related to the objective of the review was selected.Some classical papers are also cited as per the requirement of the topic.Passiflora incarnata L.showed multifunctional medicinal properties with various applications in neuropsychiatry,oxidative stress management,antimicrobial agent,and as an anticancer agent.The U.S.Food and Drug Administration categorizes passionflower extracts as“generally recognized as safe”.However,most evidence remains preclinical,with methodological variation limiting generalisation.Standardised formulation,robust clinical trials,and in-depth in vivo studies are essential to establish its therapeutic relevance and safety in modern medicine. 展开更多
关键词 Passiflora incarnata L ANTI-DEPRESSANT antioxidant activity antimicrobial activity anti-anxiety activity anticancer activity
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Determining the Effect of Grain Size on the Microstructure and Oxidation of Nuclear Graphite
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作者 Xu Qiao Xinlei Cao +6 位作者 Yuying Zhang Wei Chen Chunzhen Yang Zhengcao Li Xing Zhou Ke Shen Zhou Zhou 《Carbon Energy》 2026年第1期138-152,共15页
Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,... Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,understanding the oxidation behavior of nuclear graphite is essential for reactor safety.The influence of oxidation involves multiple factors,including temperature,sample size,oxidant,impurities,filler type and size,etc.The size of the filler particles plays a crucial role in this study.Five ultrafine-and superfine-grained nuclear graphite samples(5.9-34.4μm)are manufactured using identical raw materials and manufacturing processes.Isothermal oxidation tests conducted at 650℃-750℃ are used to study the oxidation behavior.Additionally,comprehensive characterization is performed to analyze the crystal structure,surface morphology,and nanoscale to microscale pore structure of the samples.Results indicate that oxidation behavior cannot be predicted solely based on filler grain size.Reactive site concentration,characterized by active surface area,dominates the chemical reaction kinetics,whereas pore tortuosity,quantified by the structural parameterΨ,plays a key role in regulating oxidant diffusion.These findings clarify the dual role of microstructure in oxidation mechanisms and establish a theoretical and experimental basis for the design of high-performance nuclear graphite capable of long-term service in high-temperature gas-cooled reactors. 展开更多
关键词 DIFFUSION nuclear graphite oxidation pore structure reaction rate
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Unprecedented diphenyl ether hybrids and spiro-diphenyl ether with antioxidant activity from Aspergillus sp.F1-8A associated with toad venom
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作者 Hai-Ying Yu Yu-Wei Huang +1 位作者 Li-Ping Lin Ren-Xiang Tan 《Chinese Chemical Letters》 2026年第2期352-356,共5页
Asplactones A-E(1-5),five unique diphenyl ether hybrids,along with two rare spiro-diphenyl ethers,aspviolaceols A(6)and B(7),were isolated and characterized from Aspergillus sp.F1-8A,an endophytic fungus associated wi... Asplactones A-E(1-5),five unique diphenyl ether hybrids,along with two rare spiro-diphenyl ethers,aspviolaceols A(6)and B(7),were isolated and characterized from Aspergillus sp.F1-8A,an endophytic fungus associated with the parotoid glands of Bufo gargarizans Cantor.Compounds 1-5 represent the first examples of diphenyl ether hybrids fused with unusual moieties,including conjugatedγ-butyrolactone and cyclopentenone.Compounds 6 and 7 are the first known natural spiro-diphenyl ethers,with 6 featuring an uncommon 6/6/6/6-membered carbon skeleton,and 7 possessing a distinct 6/6/6/6/6/6-membered diphenyl ether spiro-heterodimer carbon framework.Structural elucidation was performed using a combination of spectroscopic techniques,X-ray crystallography,and quantum-chemical calculations,and plausible biosynthetic pathways were proposed.Biologically,compounds 1,2,4,6,and 7 exhibited antioxidant activity comparable to or surpassing that of vitamin C in 1,1-diphenyl-2-picrylhydrazyl(DPPH)and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate)(ABTS),and ferric reducing power assays.They also significantly improved cell viability in H2O2-induced oxidative injury assays using A549 cells. 展开更多
关键词 Diphenyl ether hybrids Spiro-diphenyl ethers Γ-BUTYROLACTONE CYCLOPENTENONE ASPERGILLUS Bufo gargarizans Cantor antioxidant activity
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Spin-state engineering of octahedral Co via tetrahedral Ni in NiCo_(2)O_(4)for electrocatalytic glucose oxidation to formate
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作者 Zihao Wang Xiran Wang +10 位作者 Baoqi Jia Yilin Zuo Lin Zhou Zining Yan Zanyang Zhu Yonghao Xiao Yunfei Zhang Yufan Yang Xin Chen Lizhen Liu Xin Zhao 《Journal of Energy Chemistry》 2026年第1期605-617,I0013,共14页
Electrocatalytic glucose oxidation to high-value chemicals provides a sustainable route for biomass valorization.NiCo-based catalysts have emerged as promising candidates for glucose oxidation reaction owing to the in... Electrocatalytic glucose oxidation to high-value chemicals provides a sustainable route for biomass valorization.NiCo-based catalysts have emerged as promising candidates for glucose oxidation reaction owing to the intrinsic activity of Ni and Co catalytic centers.However,the dynamic evolution and atomic-scale synergy between these centers remain elusive.Herein,we fabricated NiCo_(2)O_(4)nanosheets supported on nickel foam,where Ni preferentially occupies tetrahedral sites to regulate the electronic configuration of octahedral Co.Experimental and theoretical results demonstrate that the incorporation of tetrahedral Ni induces low-to-intermediate spin transition in octahedral Co,thereby optimizing eg orbital occupancy and stabilizing active sites.This spin-state engineering establishes Ni-Co synergistic catalytic centers for the selective oxidation of glucose to formate(FA).At higher potential(≥1.4 V vs.RHE),octahedral Co undergoes reconstruction into excessive active CoOOH and CoO_(2)species,resulting in glucose overoxidation to CO_(2)and intensified competitive oxygen evolution.In contrast,at lower potentials(<1.4 V vs.RHE),tetrahedral Ni facilitates electron delocalization across the Ni–O–Co lattice,thereby stabilizing octahedral Co for glucose adsorption and oxidation.Subsequently,a coupled electrocatalytic system was constructed,achieving 80.7%FA yield with 91.3%Faradaic efficiency(FE)at NiCo_(2)O_(4)anode and H2 evolution rate of 696μmol h^(−1)with 99.9%FE at Pt cathode for 2 h under 1.35 V vs.RHE.This work provides a deep insight into spin-state regulation of the catalytic center,offering valuable guidance for rational catalyst design. 展开更多
关键词 Electrocatalysis Glucose oxidation Biomass valorization Spin-state regulation FORMATE
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Multiscale investigation of oxidation mechanism in AlCrSiN multilayer coatings via experiments and ab initio molecular dynamics
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作者 Ji-yuan LIU Shu-bing HU +6 位作者 Bo PENG Jing-jing TIAN Si-qi ZENG Hai-xin CHANG Hong-ya LI Jin-ke YU Fei GUO 《Transactions of Nonferrous Metals Society of China》 2026年第2期552-570,共19页
An advanced AlCrSiN/AlCrN/CrN/Cr multilayer coating was developed via hybrid multiarc ion plating and high-power impulse magnetron sputtering.The multilayer design enhanced the substrate-coating compatibility,achievin... An advanced AlCrSiN/AlCrN/CrN/Cr multilayer coating was developed via hybrid multiarc ion plating and high-power impulse magnetron sputtering.The multilayer design enhanced the substrate-coating compatibility,achieving a critical load of 87.8 N.Silicon doping induced nanocrystallization and amorphization,increasing the hardness to 26 GPa.At high temperatures,a nanoscale Cr-rich(Cr,Al)_(2)O_(3) layer was formed,effectively inhibiting oxygen diffusion.The coating underwent unique phase transformations,during which Cr_(2)N and amorphous Si3N4 were converted into dispersed SiCr_(3) nanoparticles,which stabilized Cr atoms and suppressed their outward diffusion.Ab initio molecular dynamics simulations revealed that Cr atoms exhibited higher chemical activity and oxygen-capture capability than Al atoms and Si atoms served as diffusion barriers by pinning onto the oxidized surface,considerably improving the oxidation resistance of the coating. 展开更多
关键词 physical vapor deposition AlCrSiN coating oxidation AIMD simulation
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Microenvironment accessibility enables rare oxidation type of triterpenoids by plant P450
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作者 Wentao Sun a b Lin Xiang c +4 位作者 Runming Wang Meilan Huang Bo Lv Youcai Hu Chun Li 《Chinese Chemical Letters》 2026年第2期297-302,共6页
Triterpenoids are valuable medicinal scaffolds,characterized by excellent pharmacological properties and the presence of hydroxyl and carboxyl groups that allow for further structural modifications.Expanding the scope... Triterpenoids are valuable medicinal scaffolds,characterized by excellent pharmacological properties and the presence of hydroxyl and carboxyl groups that allow for further structural modifications.Expanding the scope of oxidative modifications on these molecules is crucial for increasing their synthetic structural diversity and unlocking new potential pharmacological activities.However,the progress has been limited by the scarcity of suitable tailoring enzymes.Here,we reported a break-through in achieving targeted and remote dual-site oxidation of licorice triterpenoids using a single P450 mutant.This approach successfully enabled the selective synthesis of the rare triterpenoid,liquiritic acid and 24-OH-liquiritic acid.Our findings demonstrate that microenvironmental accessibility engineering of triterpenoid substrates within the P450 enzyme is essential for continuous and regioselective oxidation.This study not only sheds light on the mechanistic aspects of P450 catalysis but also expands the enzymatic toolkit for selective oxidative modifications in triterpenoid biosynthesis. 展开更多
关键词 Microenvironment accessibility P450 TRITERPENOID Enzyme engineering Remote oxidation
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Atomically Dispersed Pt-Ru Dual-Atom Catalysts for Efficient Low-Temperature CO Oxidation Reaction
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作者 Yanan Qi Hongqiu Chen +12 位作者 Feng Hong Xiangbin Cai Zhehan Ying Jiangyong Diao Zhimin Jia Jiawei Chen Ning Wang Shengling Xiang Xiaowen Chen Guodong Wen Bo Sun Geng Sun Hongyang Liu 《Nano-Micro Letters》 2026年第5期816-830,共15页
Single-atom catalysts(SACs)have demonstrated excellent performance in heterogeneous catalytic reactions owing to their maximized atomic efficiency,distinctive geometric,and electronic configurations.However,the effica... Single-atom catalysts(SACs)have demonstrated excellent performance in heterogeneous catalytic reactions owing to their maximized atomic efficiency,distinctive geometric,and electronic configurations.However,the efficacy of SACs remains limited for certain reactions requiring simultaneous activation of multiple reactants over metallic active sites.Herein,we report an atomically dispersed Pt1Ru1 dual-atom pair site anchored on nanodiamond@graphene(ND@G)for CO oxidation.The Pt1Ru1 dual-atom catalyst shows an exceptional turnover frequency(TOF)of 17.6.10^(-2)s^(-1)at significantly lower temperature(30℃),achieving a tenfold increase in TOF compared to singleatom Pt1/ND@G catalyst(1.5.10^(-2)s^(-1))and surpassing to previously reported Pt-based catalysts under similar conditions.Moreover,the catalyst demonstrates excellent stability,maintaining its activity for 40 h at 80℃without significant deactivation.The superior catalytic performance of Pt-Ru dual-atom catalysts is attributed to the synergistic effect between Pt and Ru atoms with enhanced metallicity for improving simultaneous adsorption and activation of CO and O_(2),and the tuning of conventional competitive reactant adsorption into a non-competitive pathway over dual-atom pair sites.The present work manifests the advantages of dual-atom pair sites in heterogeneous catalysis and paves the way for precise design of catalysts at the atomic scale. 展开更多
关键词 CO oxidation Atomically dispersed Dual-atom catalysts Pt-Ru Synergistic effect
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