期刊文献+
共找到1,927篇文章
< 1 2 97 >
每页显示 20 50 100
A Pair of New Spirocyclic Alkaloid Enantiomers with TrxR Inhibitory Activities Were Isolated from Marine-Derived Aspergillus ruber TX-M4-1 被引量:1
1
作者 WANG Cong WANG Yufei +4 位作者 SUN Jian WANG Shiyi DU Weisheng ZHOU Liman KONG Fandong 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第6期1677-1682,共6页
One new spirocyclic alkaloid,5-isopentenyl-cryptoechinuline D(1),along with 11 known compounds(2–12),were iso-lated from a marine fungus Aspergillus ruber TX-M4-1.The structures of compounds 1–12 were elucidated by ... One new spirocyclic alkaloid,5-isopentenyl-cryptoechinuline D(1),along with 11 known compounds(2–12),were iso-lated from a marine fungus Aspergillus ruber TX-M4-1.The structures of compounds 1–12 were elucidated by spectroscopic evi-dences.Compound 1 was initially isolated as an enantiomer,and further separation of 1 by chiral HPLC afforded a pair of enantio-mers,including(-)-5-isopentenyl-cryptoechinuline D(1a)and(+)-5-isopentenyl-cryptoechinuline D(1b).Their absolute configura-tions were elucidated by ECD spectroscopic data.Compounds 1a,5 and 10 could inhibit thioredoxin reductase(TrxR)activity with IC50 values of 6.2,36.3 and 18.6μmol L^(-1),respectively.Surface plasmon resonance(SPR)study also demonsrated the interactions between compounds 6,8 and Niemann-Pick C1 Like 1(NPC1L1)respectively,which indicate that compounds 6 and 8 are potential NPC1L1 inhibitors. 展开更多
关键词 Aspergillus ruber TX-M4-1 spirocyclic alkaloid TrxR inhibitory activity
下载PDF
QSAR Studies on the Inhibitory Activityof Levofloxacin-thiadiazole HDACi Conjugates to Histone Deacetylases 被引量:23
2
作者 王超 冯长君 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第11期1679-1688,共10页
A molecular electronegativity distance vector(M)based on 13 atomic types has been used to describe the structures of 19 conjugates(LHCc)of levofloxacin-thiadiazole HDAC inhibitor(HDACi)and related inhibitory activitie... A molecular electronegativity distance vector(M)based on 13 atomic types has been used to describe the structures of 19 conjugates(LHCc)of levofloxacin-thiadiazole HDAC inhibitor(HDACi)and related inhibitory activities(pH,i=1,2,6)of LHCc against histone deacetylases(HDACs,such as HDAC1,HDAC2 and HDAC6).The quantitative structure-activity relationships(QSAR)were established by using leaps-and-bounds regression analysis for the inhibitory activities(pH)of 19 above compounds to HDAC1,HDAC2 and HDAC6 along with M.The correlation coefficients(R~2)and the leave-one-out(LOO)cross validation Rfor the pH,pHand pHmodels were 0.976 and 0.949;0.985 and 0.977;0.976 and 0.932,respectively.The QSAR models had favorable correlations,as well as robustness and good prediction capability by R~2,F,R~2,A,Fand Vtests.Validated by using 3876 training sets,the models have good external prediction ability.The results indicate that the molecular structural units:–CH–(g=1,2),–NH,–OH,=O,–O–and–S–are the main factors which can affect the inhibitory activity of pH,pHas well as pHbioactivities of these compounds directly.Accordingly,the main interactions between HDACs inhibitor and HDACs are hydrophobic interaction,hydrogen bond,and coordination with Znto form compounds,which is consistent with the results in reports. 展开更多
关键词 levofloxacin-thiadiazole HDACi conjugates(LHCc) histone deacetylases(HDACs) inhibitory activity(pHi i = 1 2 6) molecular electronegativity distance vector quantitative structure-activity relationship(QSAR)
下载PDF
Moving fast, thinking fast:The relations of physical activity levels and bouts to neuroelectric indices of inhibitory control in preadolescents 被引量:3
3
作者 Dominika M.Pindus Eric S.Drollette +9 位作者 Lauren B.Raine Shih-Chun Kao Naiman Khan Daniel R.Westfall Morgan Hamill Rebecca Shorin Emily Calobrisi Dinesh John Arthur F.Kramer Charles H.Hillman 《Journal of Sport and Health Science》 SCIE 2019年第4期301-314,共14页
Background:Structured vigorous physical activity(VPA)can improve cognitive control in children,but studies relating daily physical activity(PA)to cognitive control have yielded conflicting findings.While objectively m... Background:Structured vigorous physical activity(VPA)can improve cognitive control in children,but studies relating daily physical activity(PA)to cognitive control have yielded conflicting findings.While objectively measured daily PA summarizes all occurrences of PA within a registered period,a minimum duration of continuous PA is required for registration of a PA bout.Because brief bouts of high-intensity PA can account for a large proportion of children’s daily activity-related energy expenditure,this study assessed whether daily and bouted VPA were selectively related to cognitive control in preadolescents relative to other PA intensities.Methods:A total of 75 children between the ages of 8 and 10 years(49%girls)wore an ActiGraph wGT 3 X+on the hip for 7 days.The acceleration signal from the vertical axis was summarized over 1 s,5 s,and 15 s epochs.Daily and boutecd modercate PA,moderate-to-vigorous PA,and VPA were measured.PA bouts were expressed as the frequency and time spent in 2 different continuous PA bouts,one lasting≥10 s and the other lasting≥30 s at a given intensity.Inhibitory control was assessed using behavioral responses to a modified flanker task(mean reaction time(RTmean)and accuracy).Attentional resource allocation and co gnitive processing speed were measured using the amplitude and latency of the P3 component of event-related brain potentials,respectively.Associations between PA,behavioral indices of inhibitory control,P3 amplitude,and latency were assessed using hierarchical regression models.Results:Daily VPA was not related to RTmean or accuracy on either congruent or incongruent trials.In contrast,more time spent in VPA bouts lasting≥30 s predicted shorter P3 latency across epochs and flanker congruencies(allβ≤-0.24,all p≤0.04).The associations between shorter P3 latency and the time spent in moderate-to-vigorous PA bouts lasting≥30 s were less consistent and largely limited to congruent trials(congruent:β(-0.3 1,-0.34)).No significant associations were observed upon correction for false discovery rate.Conclusion:The pattern of uncorrected associations aligns with the dose-response literature and suggests that brief VPA bouts may yield the greatest benefits to cognitive processing speed in preadolescents.Future studies using measures of brain structure and function are needed to understand the mechanisms linking bouted VPA to neurocognitive function during childhood. 展开更多
关键词 ACCELEROMETRY Bouts Children ERPS inhibitory control P3 Physical activity
下载PDF
Lipase inhibitory activity of Lagenaria siceraria fruit as a strategy to treat obesity 被引量:3
4
作者 Maria Maqsood Dildar Ahmed +1 位作者 Iqra Atique Wajeeha Malik 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2017年第3期285-290,共6页
Objective:To explore pancreatic lipase inhibitory activity under different extraction conditions in order to track the most potent extract.Methods:The methanolic extract and its fractions in solvents of increasing pol... Objective:To explore pancreatic lipase inhibitory activity under different extraction conditions in order to track the most potent extract.Methods:The methanolic extract and its fractions in solvents of increasing polarity,ether,chloroform,ethyl acetate,n-butanol and water,were made through cold maceration.Extracts in ethanol,ethyl acetate,acetone and chloroform were similarly prepared.Aqueous extract was prepared through hot decoction method.A reported method was used to determine lipase inhibitory activity of extracts and fractions over wide ranges of concentrations.Results:The extracts and fractions exhibited concentration dependent activity.The IC50(μg/mL)values of methanolic,ethanolic,chloroform,ethyl acetate,acetone,ethyl acetate(after washing with water)and aqueous decoction were 293.40,266.47,157.59,182.12,352.34,257.00,and 190.00,respectively.The activity of chloroform,ethyl acetate and aqueous extracts were close to that of the drug orlistat(IC50 146μg/mL).Out of the fractions of the methanolic extract,the chloroform fraction was most active(IC50 189.6μg/mL).The order of inhibitory activity of the fractions was as follows:chloroform>ether>n-butanolic>aqueous>ethyl acetate.The GC/MS analysis of the most active chloroform faction showed the presence of hexadecanoic acid,methyl hexadecanoate,isopropyl palmitate,methyl 9,12-octadecadienate,and methyl 9,12,15-octadecatrienoate.Conclusions:The study suggests that Lagenaria siceraria has potential to inhibit pancreatic lipase activity,suppressing lipid digestion and thereby diminishing entry of lipids into the body.Regular intake of aqueous decoction of the fruit may therefore be recommended for control of obesity.Fatty acids and their esters may play role as inhibitors of lipase. 展开更多
关键词 Lagenaria siceraria OBESITY Lipase inhibitory activity Bottle gourd
下载PDF
Phenol content,antioxidant and tyrosinase inhibitory activity of mangrove plants in Micronesia 被引量:2
5
作者 Sung-Suk Suh Jinik Hwang +2 位作者 Mirye Park Heung-Sik Park Taek-Kyun Lee 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2014年第7期531-535,共5页
Objective:To find out and compare the in vitro antioxidant and tyrosinase inhibitory activities of two species of mangrove plants.Methods:Mangrove samples were harvested at the shoreline on the island of Weno,Chuuk St... Objective:To find out and compare the in vitro antioxidant and tyrosinase inhibitory activities of two species of mangrove plants.Methods:Mangrove samples were harvested at the shoreline on the island of Weno,Chuuk State in Micronesia.The phenol content,antioxidant activity(based on DPPH-free radical scavenging)and tyrosinase inhibitory activity in different tissues(leaves,barks and roots)of Rhizophora stylosa(R.stylosa)and Sonneratia alba(S.alba),collected from the island of Weno.Results:Total phenol content ranged from 4.87 to 11.96 mg per g of freeze dried samples.The highest antioxidant activity was observed in R.styiosa bark(85.5%).The highest tyrosinase inhibitory activity was found in S.alba bark.Also,total phenol content and antioxidant activity were higher in methanol extracts than in aqueous extracts.Conclusions:Taken together,the results of this study proved that mangroves can be excellent sources of antioxidant compounds. 展开更多
关键词 RHIZOPHORA stylosa SONNERATIA alba Phebolics ANTIOXIDANT activity Tyrosinase inhibitory activity
下载PDF
In vitro Inhibitory Activity of Shisandra chinensis and Polygonatum sibiricum against Vibrio harveyi and Its Biofilms 被引量:4
6
作者 Zhifeng HUANG Huanying PANG +3 位作者 Yang HUANG Yucong HUANG Yishan LU Jichang JIAN 《Agricultural Biotechnology》 CAS 2016年第4期57-60,共4页
[Objective] This study aimed to analyze the in vitro inhibitory activity of Shisandra chinensis and Polygonatum sibiricum against Vibrio harveyi and its biofilms. [Result] By agar diffusion test, in vit... [Objective] This study aimed to analyze the in vitro inhibitory activity of Shisandra chinensis and Polygonatum sibiricum against Vibrio harveyi and its biofilms. [Result] By agar diffusion test, in vitro inhibitory activity of 5. chinensis and P. sibiricum against V. harveyi was investigated. The minimal inhibitory concentration ( MIC) and minimal bactericidal concentration (MBC) of 5. chinensis and P. sibiricum against V. harveyi were determined by doubling dilution meth-od. The inhibitory activity of 5. chinensis and P. sibiricum on the formation of V. harveyi biofilms was evaluated by modified MTT assay. [ Result ] Both 5. chinen-sis and P. sibiricum had inhibitory activity against V. harveyi. The inhibition zone diameter of 5. chinensis against V. harveyi was 17. 95 mm; MIC and MBC of 5. chinensis were both 3.125 mg/ml. The inhibition zone diameter of P. sibiricum against V. harveyi was 12. 22 mm; MIC and MBC of P. sibiricum were 3.125 and 6.250 mg/ml, respectively. When the concentration was higher than 6. 25 mg/ml, 5. chinensis decoction had extremely significant inhibitory activity against V. harveyi (P 〈 0. 01) ; when the concentration was higher than 3. 125 mg/ml, P. sibiricum had extremely significant inhibitory activity against V. harveyi (P 〈0. 01). [ Conclusion] 5. chinensis and P. sibiricum could significantly inhibit V. harveyi and its biofilms. 展开更多
关键词 Shisandra chinensis Polygonatum sibiricum Vibrio harveyi In vitro inhibitory activity BIOFILM
下载PDF
Identification and dipeptidyl peptidase Ⅳ(DPP-Ⅳ) inhibitory activity verification of peptides from mouse lymphocytes 被引量:3
7
作者 Juan Wang Yujia Xie +4 位作者 Yuanyuan Luan Tingting Guo Shanshan Xiao Xingxing Zeng Shaohui Zhang 《Food Science and Human Wellness》 SCIE 2022年第6期1515-1526,共12页
The objective of this study was to isolate and identify the intracellular bioactive peptides from mouse lymphocytes before and after lipopolysaccharide(LPS)stimulation,to explore novel peptides and to research the bio... The objective of this study was to isolate and identify the intracellular bioactive peptides from mouse lymphocytes before and after lipopolysaccharide(LPS)stimulation,to explore novel peptides and to research the bioactive function.Mouse spleen lymphocytes were isolated and cultured with LPS stimulation(experimental group)or not(control group)to collect intracellular peptides.Totally 385 peptides were analyzed by nanoliter liquid phase-Q Exactive quadrupole ultra-high resolution orbitrap mass spectrometer(Nano LC-Q Exactive Plus)and identifi ed by PEAKS X software.After compared with peptides reported,131 novel peptides were discovered,which then were predicted bioactivity by Peptide Ranker and 6 peptides with high bioactivity were predicted function by BIOPEP-UMW database.Prediction data showed that they may have dipeptidyl peptidase IV(DPP-IV)inhibitory activity.Finally,two peptides showed better potent inhibition were verifi ed with competitive and noncompetitive modes. 展开更多
关键词 LYMPHOCYTES PEPTIDES LIPOPOLYSACCHARIDE Dipeptidyl peptidaseⅣ(DPP-Ⅳ)inhibitory activity
下载PDF
The influence of Lactobacillus plantarum fermentation in selenium-enriched Brassica napus L.:changes in the nutritional constituents,bioactivities and bioaccessibility
8
作者 Wen Wang Zhixiong He +3 位作者 Ruiying Zhang Min Li Zhenxia Xu Xia Xiang 《Oil Crop Science》 CSCD 2024年第2期81-90,共10页
Selenium(Se)-enriched Brassica napus L.is a valuable organic Se supplement.In this study,the fermentation broth enriched with organic Se(FFS)was prepared using Lactobacillus plantarum to ferment the substrate of Se-en... Selenium(Se)-enriched Brassica napus L.is a valuable organic Se supplement.In this study,the fermentation broth enriched with organic Se(FFS)was prepared using Lactobacillus plantarum to ferment the substrate of Se-enriched Brassica napus L.Significant increases were observed after fermentation in total sugars,reducing sugars,soluble proteins,total phenolic content(TPC),and total flavonoid content(TFC).The organic Se was retained at a concentration of 54.75 mg/g in the freeze-dried sample.Principal component analysis and cluster analysis showed good separation between the FFS and unfermented(FS)groups.Fragrant 2-ethyloxetane had the highest content among all volatiles,while sinapine had the highest content among all phenolic compounds.The fermentation process showed remarkable improvement in the abundance and concentration of volatile compounds and phenolic contents,making FFS exhibit strong antioxidant activity and inhibitory capacity againstα-glucosidase activity.The bioaccessibility of phenolic compounds was significantly greater in FFS compared to FS.ADMET analysis revealed that the majority of phenolic compounds contained in FFS did not exhibit mutagenicity toxicity,hepatotoxicity,skin sensitization,or blood-brain barrier penetration,indicating a favorable level of biosafety.Overall,our study provides a new insight into the further utilization of Se-enriched Brassica napus L.in foods. 展开更多
关键词 Se-enriched Brassica napus L. FERMENTATION Antioxidant activity inhibitory activity BIOACCESSIBILITY
下载PDF
Crystal Structure and Inhibitory Activity against Xanthine Oxidase of Bis(μ_2-chloro)-chloro-(μ-N,N'-(2-pyridylmethylene) Furanmethanoamine Copper(II) Complex
9
作者 方瑞琴 史大华 +1 位作者 石磊 朱海亮 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第3期345-349,共5页
A chloro-bridged dinuclear copper(H) complex with ligand 2-pyridylme-thylene- furfurylamine has been synthesized and characterized by single-crystal X-ray diffraction, and its inhibitory activity on xanthine oxidase... A chloro-bridged dinuclear copper(H) complex with ligand 2-pyridylme-thylene- furfurylamine has been synthesized and characterized by single-crystal X-ray diffraction, and its inhibitory activity on xanthine oxidase (XO) was also evaluated. It crystallizes in the triclinic system, space group P 1 with a = 8.0441(16), b = 8.5663(17), c = 10.060(2)A, α = 77.52(3), β = 72.04(3), γ = 70.12(3)°, V = 615.3(2)A^3, Z = 1, Dc = 1.731 g/cm^3, F(000) = 322, the final R = 0.0401 and wR = 0.0934 for 1971 observed reflections with I 〉 2σ(I). X-ray analysis reveals that the Cu(II) cation is five-coordinated by two N atoms of Schiff base and three Cl anions. The C-H…Cl intermolecular and intramolecular hydrogen bonds connect the molecules to form a three-dimensional network. This copper(II) complex shows more potent inhibitory activity against XO with IC50 = 3.48μM than the standard inhibitor allopurinol. 展开更多
关键词 dinudear copper(II) complex 2-pyridineaidehyde FURFURYLAMINE Schiff base inhibitory activity against XO
下载PDF
Development and assessment of tyrosinase inhibitory activity of liposomes of Asparagus racemosus extracts
10
作者 Narin Therdphapiyanak Montree Jaturanpinyo +2 位作者 Neti Waranuch Lalana Kongkaneramit Narong Sarisuta 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2013年第2期134-142,共9页
The purpose of this study was to develop liposomal formulations of Asparagus racemosus root extract(AR1-6)as well as evaluate the physicochemical properties and in vitro tyrosinase inhibitory activity.Liposomes compos... The purpose of this study was to develop liposomal formulations of Asparagus racemosus root extract(AR1-6)as well as evaluate the physicochemical properties and in vitro tyrosinase inhibitory activity.Liposomes composed of AR1-6 to lipid weight ratio of 1:10 and lecithin(LEC)or Phospholipon90G(PC90G)as structural phospholipid at 7:3 molar ratio to CHOL were prepared by various methods,i.e.chloroform-film(CF),reverse-phase evaporation(REV),polyol dilution(PD),and freeze-drying of monophase solution(MFD)methods.The results revealed that vesicles prepared by CF and MFD were multilamellar whereas those prepared by REV and PD were oligolamellar in nature with particle sizes ranging from 0.26 to 13.83 mm.The zeta potentials were in the range of1.5 to39.3 mV.AR1-6 liposomes with LEC possessed significantly higher entrapment than those with PC90G.The highest entrapment efficiency and in vitro tyrosinase inhibitory activity of 69.08%and 25%,respectively,were obtained from liposomes having LEC and prepared by PD method.The tyrosinase inhibitory activity were in the rank order of LEC>PC90G,and PD>CF>REV>MFD.It could be concluded that the mechanism of vesicle forming in each method of preparation was the key factor influencing physicochemical properties,particularly vesicle type,size,surface charge,and entrapment,which were well correlated with the biological activity. 展开更多
关键词 Asparagus racemosus Liposomes Lipid composition Method of preparation Tyrosinase inhibitory activity
下载PDF
<i>In-Vitro</i>Inhibitory Effect of Methanol Extracts of Chinese Herbal Drugs on Supercoiling Activity of Bacterial DNA Gyrase
11
作者 Hui Xu Huizhi Chen +2 位作者 Pan Yao Guodong Lin Weiwen Chen 《Chinese Medicine》 2013年第1期19-23,共5页
A large number of Chinese herbal drugs (CHDs) exhibit antibacterial activities both in vivo and in vitro, but until now little is known regarding their inhibitory mechanisms. Bacterial DNA gyrase is a proven target fo... A large number of Chinese herbal drugs (CHDs) exhibit antibacterial activities both in vivo and in vitro, but until now little is known regarding their inhibitory mechanisms. Bacterial DNA gyrase is a proven target for antibacterial agents. Aim of this study was to investigate the in-vitro inhibitory effect of methanol extracts of CHDs against supercoiling activity of bacterial DNA gyrase. Fifteen CHDs were selected and extracted with methanol, respectively. Inhibitory effect of the extracts on DNA gyrase was tested using gel-based DNA supercoiling assay. Among fifteen CHDs tested, methanol extracts of Lonicerae Japonicae Flos (S2), Taraxaci Herba (S7), Glycyrrhizae Radix et Rhizoma Praeparata cum Melle (S8) demonstrated an obvious inhibitory effect against supercoiling activity of DNA gyrase, and the others were either less active or could not be determined with the present method. Moreover, it was likely that S7 and S8 inhibit gyrase in a concentration-dependent manner. In conclusion, DNA supercoiling assay is a promising method to study the inhibitory activity of CHDs on bacterial DNA gyrase. Some CHDs do have gyrase-inhibitory activity as proposed. Further investigations are needed to elucidate the inhibition mechanism of these CHDs on supercoiling activity of gyrase. 展开更多
关键词 CHINESE Herbal Drugs BACTERIAL DNA GYRASE SUPERCOILING activity inhibitory Effect
下载PDF
Exploring QSARs for Inhibitory Activity of Cyclic Urea and Nonpeptide-Cyclic Cyanoguanidine Derivatives HIV-1 Protease Inhibitors by Artificial Neural Network
12
作者 Omar Deeb Mohammad Jawabreh 《Advances in Chemical Engineering and Science》 2012年第1期82-100,共19页
Quantitative structure–activity relationship study using artificial neural network (ANN) methodology were conducted to predict the inhibition constants of 127 symmetrical and unsymmetrical cyclic urea and cyclic cyan... Quantitative structure–activity relationship study using artificial neural network (ANN) methodology were conducted to predict the inhibition constants of 127 symmetrical and unsymmetrical cyclic urea and cyclic cyanoguanidine derivatives containing different substituent groups such as: benzyl, isopropyl, 4-hydroxybenzyl, ketone, oxime, pyrazole, imidazole, triazole and having anti-HIV-1 protease activities. The results obtained by artificial neural network give advanced regression models with good prediction ability. The two optimal artificial neural network models obtained have coefficients of determination of 0.746 and 0.756. The lowest prediction’s root mean square error obtained is 0.607. Artificial neural networks provide improved models for heterogeneous data sets without splitting them into families. Both the external and cross-validation methods are used to validate the performances of the resulting models. Randomization test is employed to check the suitability of the models. 展开更多
关键词 QSAR MLR PC ANN inhibitory activity CYCLIC UREA and Nonpeptide-Cyclic Cyanoguanidine DERIVATIVES HIV-1 Protease
下载PDF
Cantharidin and Its Analogues:Anticancer and Ser/Thr Protein Phosphatase Inhibitory Activities 被引量:5
13
作者 史清华 王玉玲 +1 位作者 宋宏锐 程卯生 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第4期250-256,共7页
This paper mainly describes the anticancer activities and Ser/Thr protein phosphatase inhibitory activities of cantharidin and its analogues.
关键词 cantharidin analogues anticancer activity Ser/Thr protein phosphatase inhibitory activity
下载PDF
Acarbose glycosylation by AcbE for the production of acarstatins with enhancedα-amylase inhibitory activity
14
作者 Xin Zhang Qungang Huang +3 位作者 Ziyue Guo Feifei Cai Qianjin Kang Linquan Bai 《Synthetic and Systems Biotechnology》 SCIE CSCD 2024年第2期359-368,共10页
Acarbose is a potent glycosidase inhibitor widely used in the clinical treatment of type 2 diabetes mellitus(T2DM).Various acarbose analogs have been identified while exploring compounds with improved pharmacological ... Acarbose is a potent glycosidase inhibitor widely used in the clinical treatment of type 2 diabetes mellitus(T2DM).Various acarbose analogs have been identified while exploring compounds with improved pharmacological properties.In this study,we found that AcbE from Actinoplanes sp.SE50/110 catalyzes the production of acarbose analogs that exhibit significantly improved inhibitory activity towardsα-amylase than acarbose.Recombinant AcbE mainly catalyzed the formation of two new compounds,namely acarstatins A and B,using acarbose as substrate.Using high-resolution mass spectrometry,nuclear magnetic resonance,and glycosidase hydrolysis,we elucidated their chemical structures as O-α-d-maltosyl-(1→4)-acarbose and O-α-d-maltotriosyl-(1→4)-acarbose,respectively.Acarstatins A and B exhibited 1584-and 1478-fold greater inhibitory activity towards human salivaryα-amylase than acarbose.Furthermore,both acarstatins A and B exhibited complete resistance to microbiome-derived acarbose kinase 1-mediated phosphorylation and partial resistance to acarbose-preferred glucosidase-mediated hydrolysis.Therefore,acarstatins A and B have great potential as candidate therapeutic agents for T2DM. 展开更多
关键词 Acarbose analogs α-amylase inhibitory activity Actinoplanes sp. Transglycosylase
原文传递
Combined antibacterial activity of stingless bee(Apis mellipodae)honey and garlic(Allium sativum)extracts against standard and clinical pathogenic bacteria 被引量:4
15
作者 Berhanu Andualem 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第9期725-731,共7页
Objective:To investigate the synergic antibacterial activity of garlic and tazma honey against standard and clinical pathogenic bacteria.Methods:Antimicrobial activity of tazma honey,garlic and mixture of them against... Objective:To investigate the synergic antibacterial activity of garlic and tazma honey against standard and clinical pathogenic bacteria.Methods:Antimicrobial activity of tazma honey,garlic and mixture of them against pathogenic bacteria were determined.Chloramphenicol and water were used as positive and negative controls,respectively.Minimum inhibitory concentration(MIC)and minimum bactericidal concentration of antimicrobial samples were determined using standard methods.Results:Inhibition zone of mixture of garlic and tazma honey against all tested pathogens was significantly(P≤0.05)greater than garlic and tazma honey alone.The diameter zone of inhibition ranged from(18±1)to(35±1)mm for mixture of garlic and tazma honey,(12±1)to(20±1)nun for tazma honey and(14±1)to(22±1)mm for garlic as compared with(10±1)to(30±1)mm for chloramphenicol.The combination of garlic and tazma honey(30-35 mm)was more significantly(P≤0.05)effective against Salmonella(NCTC 8385),Staphylococcus aureus(ATCC 25923),Lyesria moncytogenes(ATCC 19116)and Streptococcus pneumonia(ATCC 63).Results also showed considerable antimicrobial activity of garlic and tazma honey.MIC of mixture of garlic and tazma honey at 6.25%against total test bacteria was 88.9%.MIC of mixture of garlic and tazma honey at6.25%against Gram positive and negative were 100%and 83.33%,respectively.The bactericidal activities of garlic,tazma honey,and mixture of garlic and tazma honey against all pathogenic bacteria at 6.25%concentration were 66.6%,55.6%and 55.6%,respectively.Conclusions:This finding strongly supports the claim of the local community to use the combination of tazma honey and garlic for the treatment of different pathogenic bacterial infections.Therefore,garlic in combination with tazma honey can serve as an alternative natural antimicrobial drug for the treatment of pathogenic bacterial infections.Further in vivo study is recommended to come up with a comprehensive conclusion. 展开更多
关键词 GARLIC HONEY Antimicrobial activity BACTERICIDAL activity Inhibition zone Minimum inhibitory CONCENTRATION Minimum BACTERICIDAL CONCENTRATION
下载PDF
Inhibitory effect of Houttuynia cordata Thunb on LPS-induced retinal microglial activation 被引量:4
16
作者 Ying-Hui Zhang Le-Meng Ren Xiao-Yun Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第7期1095-1100,共6页
AIM: To identify the effect of Houttuynia cordata Thunb(HCT) on lipopolysaccharide(LPS)-induced microglial activation and investigate its possible molecular mechanisms. METHODS: The primary retinal microglial cells we... AIM: To identify the effect of Houttuynia cordata Thunb(HCT) on lipopolysaccharide(LPS)-induced microglial activation and investigate its possible molecular mechanisms. METHODS: The primary retinal microglial cells were cultured from the retinas of newborn Sprague-Dawley rats and exposed to LPS, and/or HCT with different concentrations. The survival ability of retinal microglia cells was tested by standard MTT method. BrdU cell proliferation assay was used to evaluate the proliferation of retinal microglia. Inflammatory factors in the culture supernatants, including TNF-α, iNOS and IL-1β, were measured using ELISA. Microglia cells’ migration was determined with Transwell migration assay. The total p38-MAPK and phosphorylation of p38-MAPK(p-p38-MAPK) were detected with Western blot.RESULTS: Primary retinal microglia in culture exposed to LPS to induce microglia activation. Pretreatment with HCT significantly inhibited the LPS-induced cell proliferation, but not the cell viability. LPS induced inflammatory reaction in microglia and cell migration. HCT significantly reduced LPS-stimulated release of pro-inflammatory factors and decreased the number of migrating cells substantially in a concentration-dependent manner. Moreover, the protein levels of p-p38 MAPK were identified as the up regulation and co-treatment with HCT obviously inhibited the upregulation of p-p38 MAPK, but had no effect on the levels of total p38-MAPK.CONCLUSION: The data suggest that HCT inhibits LPSinduced retinal microglial activation via suppression of the p-p38-MAPK. HCT may be used for the treatment of ocular diseases characterized by over-activated microglia. 展开更多
关键词 Houttuynia cordata THUNB MICROGLIA activation RETINA inhibitory effect
下载PDF
Anti Cervix Cancer Activity of Co-immobilized Tumor Necrosis Factor-α and Interferon-γ 被引量:7
17
作者 Yanqing GUAN Limei HE +1 位作者 Shumei CAI Tianhong ZHOU 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2006年第2期200-204,共5页
Tumor necrosis factor α (TNF-α) and interferon-γ (IFN-γ) are cytokines with strong antitumor activities. They were reacted with a photoactive arylazide-4-azidobenzoic acid, resulting in photoactive TNF-α and ... Tumor necrosis factor α (TNF-α) and interferon-γ (IFN-γ) are cytokines with strong antitumor activities. They were reacted with a photoactive arylazide-4-azidobenzoic acid, resulting in photoactive TNF-α and IFN-γ. The infrared (IR) spectra of these products showed the characteristic absorption of an azido group at 2127 cm^-1. By photo-immobilization, this modified TNF-α and IFN-γ were immobilized on polystyrene membranes for cell culture to prepare biomaterials. The micro-morphology of photoactive cytokines was observed with a scanning electron microscope (SEM). The inhibitory effect on growth of Hela cells and inducing apoptosis activity of these two cytokines were analyzed by growth curve, transmission electron microscope (TEM) and fluorescence active cell sorter (FACS). The results showed that co-immobilization of IFN-γ and TNF-α had significant inhibitory effect on growth of Hela cells, inhibitory rate up to 82%, and IFN-γ had obviously synergistic action. 展开更多
关键词 Tumor necrosis factor (TNF-α) Interferon-γ (IFN-γ) Cervix cancer cell line Photo-immobilization POLYSTYRENE inhibitory activity
下载PDF
Evaluation of cytotoxic and anti-tumor activity of partially purified serine protease isolate from the Indian earthworm Pheretima posthuma 被引量:3
18
作者 Mahendra Kumar Verma Francies Xavier +1 位作者 Yogendra Kumar Verma Kota Sobha 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第11期896-901,共6页
Objective:To isolate,partially purify and evaluate the cytotoxic and antitumor activity of a serine protease from the chosen Indian earthworm Pheretima posthuma.Methods:Whole animal extract was prepared and purified i... Objective:To isolate,partially purify and evaluate the cytotoxic and antitumor activity of a serine protease from the chosen Indian earthworm Pheretima posthuma.Methods:Whole animal extract was prepared and purified its protein constituents by size and charge based chromatographic separation techniques using Sephadex G-50 and DEAE-Cellulose resin respectively.Average molecular weight of the protein isolate was determined and analyzed for its cytotoxic property against Vero cells in different dilutions(1:20 and 1:40)and anti-tumor activity by MTT assay(a colorimetric assay)using breast cancer cell line MCF-7,with tamoxifen as standard.Results:One of the protein constituents after purification was characterized as serine protease by Caseinolytic plate diffusion assay.Average molecular weight of this purified isolate was determined,by SDS-PAGE analysis with standard protein ladder,as of 15 kDa.The performed tests suggested that the 15kDa fraction has potent cytotoxic activity and satisfactory antitumor activity as well in vitro.Conclusions:Exact molecular mechanism of the cytotoxic and antitumor activities is yet to be explored and currently we are working on ultra-purification and biophysical characterization of this fraction.Further investigation into the mechanism(s)of cytotoxic and antitumor activities at molecular level would be useful in treatment of various classes of cancer and viral infections in future. 展开更多
关键词 EARTHWORM FIBRINOLYTIC enzyme Cytotoxicity Antitumor activity SERINE PROTEASE Minimum inhibitory concentration
下载PDF
Evaluation of anti-resistant activity of Auklandia(Saussurea lappa) root against some human pathogens 被引量:2
19
作者 Sidgi Syed Anwer Hasson Mohammed Saeed Al-Balushi +8 位作者 KhazinaAlharthy JumaZaidAl-Busaidi MunaSulimanAldaihani Mohammed Shafeeq Othman Elias Antony Said Omar Habal Talal Abdullah Sallam Ali Abdullah Aljabri Mohamed AhmedIdris 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第7期557-562,共6页
Objective:The antimicrobial activity of the ethanol extract of the Auklandia(Saussurea lappa)root plant was investigated to verify its medicinal use in the treatment of microbial infections.Methods:The antimicrobial a... Objective:The antimicrobial activity of the ethanol extract of the Auklandia(Saussurea lappa)root plant was investigated to verify its medicinal use in the treatment of microbial infections.Methods:The antimicrobial activity of the ethanol extract was tested against clinical isolates ofsome multidrug-resistant bacteria using the agar well diffusion method.Commercial antibioticswere used as positive reference standards to determine the sensitivity of the clinical isolates.Results:The extracts showed significant inhibitory activity against clinical isolates of methicillinresistantStaphylococcus aureus,Pseudomonas aeruginosa,Escherichia coli,Klebsiella pneumonia,Extended Spectrum Beta-Lactemase,Acinetobacter baumannii.The minimum inhibitory concentration values obtained using the agar dilution test ranged from 2.0μg/μL-12.0μg/μL.In the contrary the water extract showed no activity at all against the tested isolates.Furthermore,theresults obtained by examining anti-resistant activity of the plant ethanolic extract showed thatat higher concentration of the plant extract(12μg)all tested bacteria isolates were inhibited with variable inhibition zones similar to those obtained when we applied lower extract concentrationusing the well diffusion assay.Conclusion:The results demonstrated that the crude ethanolicextract of the Auklandia(Saussurea lappa)root plant has a wide spectrum of activity suggestingthat it may be useful in the treatment of infections caused by the above clinical isolates(humanpathogens). 展开更多
关键词 Auklandia SAUSSUREA lappa Ethanol EXTRACT ANTIMICROBIAL activity Anti-resistant activity Minimum inhibitory concentration(MIC)
下载PDF
Antifungal activity of Ocimum sanctum Linn.(Lamiaceae) on clinically isolated dermatophytic fungi 被引量:3
20
作者 Balakumar S Rajan S +1 位作者 Thirunalasundari T Jeeva S 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第8期654-657,共4页
Objective:To assess antifungal activity of Ocimum sanctum leaves against dermatophytic fungi. Methods:Antifungal activity of Ocimum sanctum leaves was measured by 38 A NCCLS method. Minimum inhibitory concentration(MI... Objective:To assess antifungal activity of Ocimum sanctum leaves against dermatophytic fungi. Methods:Antifungal activity of Ocimum sanctum leaves was measured by 38 A NCCLS method. Minimum inhibitory concentration(MIC) and minimum fungicidal concentration(MFC) of various extracts and fractions of Ocimum sanctum leaves were also determined.Results:Ocimum sanctum leaves possessed antifungal activity against clinically isolated dermatophytes at the concentration of 200μg/mL.MIC and MFC were high with water fraction(200μg/mL) against dermatophytic fungi used.Conclusions:Ocimum sanctum has antifungal activity,and the leaf extracts may be a useful source for dermatophytic infections. 展开更多
关键词 Antifungal activity DERMATOPHYTOSIS Epidermophyton floccosum Minimum fungicidal CONCENTRATION MICROSPORUM SP Minimum inhibitory CONCENTRATION OCIMUM sanctum TRICHOPHYTON SP
下载PDF
上一页 1 2 97 下一页 到第
使用帮助 返回顶部