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Ghazal F, Farooq S, Wahab AT, Maharjan R, Zafar H, Siddiqui H, Shafi S, Choudhary MI. Identification of quinoline derivatives as growth inhibitors of MDR pathogen Klebsiella pneumoniae. Future Microbiol 2022; 17:843-859. [PMID: 35796056 DOI: 10.2217/fmb-2021-0111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aims: This study was aimed to identify compounds with significant inhibitory potential against multidrug-resistant (MDR), multidrug-sensitive, and clinical isolates of Klebsiella pneumoniae. Materials & methods: Antibacterial activity of the nitroquinoline derivatives was assessed by micro-plate Alamar Blue assay. Results: Nitroquinoline derivatives 9, 11 and 14 showed inhibitory activity against MDR K. pneumoniae. Docking studies of these compounds with topoisomerase IV of K. pneumonia indicated the interactions of these compounds at the active site residues of enzyme near to cofactor (Mg+2). Furthermore, compound 11 was identified as a reactive oxygen species (ROS) inducer. None of the compounds showed hemolytic effect. Conclusion: This study was designed to identify compounds active against MDR K. pneumoniae which causes infections, such as pneumonia and urinary tract infections.
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Affiliation(s)
- Farzeen Ghazal
- HEJ Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, 75270, Pakistan
| | - Saba Farooq
- Dr Panjwani Center for Molecular Medicine and Drug Research, International Center of Chemical and Biological Sciences, University of Karachi, Karachi, 75270, Pakistan
| | - Atia-Tul Wahab
- Dr Panjwani Center for Molecular Medicine and Drug Research, International Center of Chemical and Biological Sciences, University of Karachi, Karachi, 75270, Pakistan
| | - Rukesh Maharjan
- HEJ Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, 75270, Pakistan
| | - Humaira Zafar
- Dr Panjwani Center for Molecular Medicine and Drug Research, International Center of Chemical and Biological Sciences, University of Karachi, Karachi, 75270, Pakistan
| | - Hina Siddiqui
- HEJ Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, 75270, Pakistan
| | - Sara Shafi
- HEJ Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, 75270, Pakistan
| | - M I Choudhary
- HEJ Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, 75270, Pakistan.,Dr Panjwani Center for Molecular Medicine and Drug Research, International Center of Chemical and Biological Sciences, University of Karachi, Karachi, 75270, Pakistan.,Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
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Okoro EE, Osoniyi OR, Jabeen A, Shams S, Choudhary MI, Onajobi FD. Anti-proliferative and immunomodulatory activities of fractions from methanol root extract of Abrus precatorius L. Clin Phytosci 2019. [DOI: 10.1186/s40816-019-0143-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Abrus precatorius possesses various therapeutic properties including anticancer potentials. This study evaluated the anti-proliferative activities of fractions of methanol root extract of A. precatorius on breast and cervical cancer cells and their immunomodulatory effect. Phytochemical screening was done by FTIR and GCMS. In vitro anti-proliferative effect was evaluated on human breast cancer (AU565) and cervical cancer (HeLa) cells and on murine fibroblast (NIH 3 T3) cells. Antioxidant activity was performed via DPPH radical scavenging assay. The immunomodulatory potential of fractions was evaluated by inhibition of phagocytes oxidative burst (ROS), Nitric oxide (NO) and proinflammatory cytokine TNF-α.
Results
A. precatorius fractions showed different chemical groups and were somewhat selective in antiproliferative activity against studied cancer cells. Ethyl acetate fraction showed the most significant antiproliferative activity with IC50 values of 18.10 μg/mL and 11.89 μg/mL against AU565 and HeLa cells respectively. Hexane fraction significantly (p < 0.05) inhibited HeLa cells (IC50 18.24 ± 0.16 μg/mL), whereas aqueous fraction showed mild inhibition (IC50 46.46 ± 0.14 μg/mL) on AU565 cell proliferation. All fractions showed no cytotoxicity against NIH-3 T3 murine fibroblast normal cells. All fractions showed potent and significant (p < 0.001) DPPH radical scavenging activity as well as suppressed phagocytic oxidative burst. Hexane (< 1 μg/mL), ethyl acetate (< 1 μg/mL), and butanol (5.74 μg/mL) fractions potently inhibited the cytokine TNF- α, hexane (< 1 μg/mL) and ethyl acetate (< 1 μg/mL) fractions also potently inhibited NO.
Conclusions
The antiproliferative activities and suppressive effect on the phagocytic oxidative burst, NO and proinflammatory cytokine might be due to the synergistic actions of bioactive compounds especially flavonoids present in the assayed fractions and therefore, suggest chemotherapeutic use of A. precatorius in cancer treatment.
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Waheed H, Moin SF, Choudhary MI. Snake Venom: From Deadly Toxins to Life-saving Therapeutics. Curr Med Chem 2017; 24:1874-1891. [PMID: 28578650 DOI: 10.2174/0929867324666170605091546] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 05/25/2017] [Accepted: 05/30/2017] [Indexed: 11/22/2022]
Abstract
Snakes are fascinating creatures and have been residents of this planet well before ancient humans dwelled the earth. Venomous snakes have been a figure of fear, and cause notable mortality throughout the world. The venom constitutes families of proteins and peptides with various isoforms that make it a cocktail of diverse molecules. These biomolecules are responsible for the disturbance in fundamental physiological systems of the envenomed victim, leading to morbidity which can lead to death if left untreated. Researchers have turned these life-threatening toxins into life-saving therapeutics via technological advancements. Since the development of captopril, the first drug that was derived from bradykininpotentiating peptide of Bothrops jararaca, to the disintegrins that have potent activity against certain types of cancers, snake venom components have shown great potential for the development of lead compounds for new drugs. There is a continuous development of new drugs from snake venom for coagulopathy and hemostasis to anti-cancer agents. In this review, we have focused on different snake venom proteins / peptides derived drugs that are in clinical use or in developmental stages till to date. Also, some commonly used snake venom derived diagnostic tools along with the recent updates in this exciting field are discussed.
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Affiliation(s)
- Humera Waheed
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, 75270-Karachi, Pakistan
| | - Syed F Moin
- National Center for Proteomics, University of Karachi, Karachi- 75270, Pakistan
| | - M I Choudhary
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, 75270-Karachi, Pakistan
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Mabkhot YN, Al-Showiman SS, Barakat A, Yousuf S, Choudhary MI. Regioselective synthesis and crystal structure of ethyl-4-acetyl-5-((2- ethoxy-2-oxoethyl)thio)-3-hydroxythiophene-2-carboxylate, C13H16O6S2. Z KRIST-NEW CRYST ST 2015. [DOI: 10.1515/ncrs-2015-0007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract C13H16O6S2, triclinic, P1̅ (no. 2), a = 7.979(1) Å, b = 9.189(1) Å, c = 10.263(1) Å, ɑ = 72.876(2)°, β = 71.485(2)°, γ = 76.655(2)°, V = 674.0 Å3, Z = 2, Rgt(F) = 0.0360, wRref(F2) = 0.0962, T = 273 K.
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Affiliation(s)
- Y. N. Mabkhot
- 1Department of Chemistry, College of Science, King Saud University, P. O. Box 2455, Riyadh-11451, Saudi Arabia
| | - S. S. Al-Showiman
- 1Department of Chemistry, College of Science, King Saud University, P. O. Box 2455, Riyadh-11451, Saudi Arabia
| | - A. Barakat
- 1Department of Chemistry, College of Science, King Saud University, P. O. Box 2455, Riyadh-11451, Saudi Arabia
- 2Department of Chemistry, Faculty of Science, Alexandria University, P.O. Box 426, Ibrahimia- 21321 Alexandria, Egypt
| | - S. Yousuf
- 3H.E.J. Research Institute of Chemistry, International Center for Chemical Sciences, University of Karachi, Karachi-75270, Pakistan
| | - M. I. Choudhary
- 1Department of Chemistry, College of Science, King Saud University, P. O. Box 2455, Riyadh-11451, Saudi Arabia
- 3H.E.J. Research Institute of Chemistry, International Center for Chemical Sciences, University of Karachi, Karachi-75270, Pakistan
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Kazeem MI, Akanji MA, Hafizur RM, Choudhary MI. Antiglycation, antioxidant and toxicological potential of polyphenol extracts of alligator pepper, ginger and nutmeg from Nigeria. Asian Pac J Trop Biomed 2012; 2:727-32. [PMID: 23570003 PMCID: PMC3609371 DOI: 10.1016/s2221-1691(12)60218-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2012] [Revised: 03/03/2012] [Accepted: 04/23/2012] [Indexed: 02/05/2023] Open
Abstract
OBJECTIVE To evaluate the antioxidant and antiglycation potential of polyphenols from three spices; alligator pepper, ginger and nutmeg. METHODS Polyphenol extracts of these spices were subjected to brine-shrimp lethality assay, phytotoxicity test, DPPH and superoxide anion radical scavenging as well as BSA-glucose antiglycation assay. RESULTS Results obtained showed that polyphenol extract of ginger has the highest antioxidant potential with IC50 0.075 and 0.070 mg/mL for DPPH and superoxide anion radical scavenging assay while alligator pepper displayed highest antiglycation activity with IC50 0.125 mg/mL. However, nutmeg extract exhibited weakest cytotoxic and phytotoxic potential with LD50 4359.70 and 1490 µg/mL respectively. CONCLUSIONS It can be concluded that the polyphenol extracts of alligator pepper, ginger and nutmeg displayed good antioxidant as well as antiglycation potential and are safe for consumption.
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Affiliation(s)
- MI Kazeem
- Department of Biochemistry, University of Ilorin, PMB 1515, Ilorin, Nigeria
- Department of Biochemistry, Lagos State University, PMB 0001, Ojo, Lagos, Nigeria
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi-75270, Pakistan
| | - MA Akanji
- Department of Biochemistry, University of Ilorin, PMB 1515, Ilorin, Nigeria
| | - Rahman M Hafizur
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi-75270, Pakistan
| | - MI Choudhary
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi-75270, Pakistan
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Iqbal S, Akrem A, Buck F, Perbandt M, Banumathi S, Choudhary MI, Betzel C. Crystallization and structure determination of a Crocus sativuscysteine protease. Acta Crystallogr A 2012. [DOI: 10.1107/s010876731209678x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023] Open
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Khan KM, Shah Z, Ahmad VU, Ambreen N, Khan M, Taha M, Rahim F, Noreen S, Perveen S, Choudhary MI, Voelter W. 6-Nitrobenzimidazole derivatives: potential phosphodiesterase inhibitors: synthesis and structure-activity relationship. Bioorg Med Chem 2011; 20:1521-6. [PMID: 22264761 DOI: 10.1016/j.bmc.2011.12.041] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2011] [Revised: 12/19/2011] [Accepted: 12/19/2011] [Indexed: 11/17/2022]
Abstract
6-Nitrobenzimidazole derivatives (1-30) synthesized and their phosphodiesterase inhibitory activities determined. Out of thirty tested compounds, ten showed a varying degrees of phosphodiesterase inhibition with IC(50) values between 1.5±0.043 and 294.0±16.7 μM. Compounds 30 (IC(50)=1.5±0.043 μM), 1 (IC(50)=2.4±0.049 μM), 11 (IC(50)=5.7±0.113 μM), 13 (IC(50)=6.4±0.148 μM), 14 (IC(50)=10.5±0.51 μM), 9 (IC(50)=11.49±0.08 μM), 3 (IC(50)=63.1±1.48 μM), 10 (IC(50)=120.0±4.47 μM), and 6 (IC(50)=153.2±5.6 μM) showed excellent phosphodiesterase inhibitory activity, much superior to the standard EDTA (IC(50)=274±0.007 μM), and thus are potential molecules for the development of a new class of phosphodiesterase inhibitors. A structure-activity relationship is evaluated. All compounds are characterized by spectroscopic parameters.
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Affiliation(s)
- K M Khan
- H.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan.
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Yousuf S, Musharraf SG, Iqbal N, Adhikari A, Choudhary MI. 3α-Dimethylamino-20-( N-methylacetamido)pregn-5-ene. Acta Crystallogr Sect E Struct Rep Online 2011; 67:o2918. [PMID: 22219950 PMCID: PMC3247332 DOI: 10.1107/s160053681103964x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Accepted: 09/27/2011] [Indexed: 11/17/2022]
Abstract
The title compond, C26H44N2O, is an steroidal alkaloid isolated from the medicinally important plant Sarcococca saligna. The molecule consists of four fused rings (A–D), having chair, half-chair, chair and envelope conformations, respectively. The dimethylamino group is axially oriented on ring A, whereas the (N-methylacetamido)ethyl group is attached equatorially on ring D. The crystal structure is stabilized only by van der Waals forces.
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Rauf A, Ahmed F, Qureshi AM, Aziz-ur-Rehman, Khan A, Qadir MI, Choudhary MI, Chohan ZH, Youssoufid MH, Haddad TB. Synthesis and Urease Inhibition Studies of Barbituric and Thiobarbituric Acid Derived Sulphonamides. J CHIN CHEM SOC-TAIP 2011. [DOI: 10.1002/jccs.201190017] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Yousuf S, Bibi M, Choudhary MI. 21-Hydroxypregna-1,4-diene-3,20-dione. Acta Crystallogr Sect E Struct Rep Online 2011; 67:o2122. [PMID: 22091140 PMCID: PMC3213563 DOI: 10.1107/s1600536811028674] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2011] [Accepted: 07/17/2011] [Indexed: 11/23/2022]
Abstract
The title compound, C21H28O3, is a fungal transformed metabolite of decoxycorticosterone acetate, consisting of four fused rings A, B, C and D. Ring A is nearly planar, with a maximum deviation of 0.010 (3) Å from the least-squares plane, while the trans-fused rings B and C adopt chair conformations. The five-membered ring D is in an envelope conformation. The orientation of the side chain is stabilized by an intramolecular O—H⋯O hydrogen bond. In the crystal, adjecent molecules are linked by C—H⋯O hydrogen bonds into extended zigzag chains along the a axis.
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Khan KM, Iqbal S, Lodhi MA, Maharvi GM, Perveen S, Choudhary MI, Chohan ZH, Supuran CT. Synthesis and Urease Enzyme Inhibitory Effects of Some Dicoumarols. J Enzyme Inhib Med Chem 2011; 19:367-71. [PMID: 15558955 DOI: 10.1080/14756360409162452] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
Dicoumarols 1-10 with substituted phenyl residues at C-11 were synthesized and screened for their urease inhibition effects. All synthesized compounds showed varying degree of urease inhibitory activity ranging from IC50 = 74.30-91.35 microM.
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Affiliation(s)
- Khalid M Khan
- H.E.J. Research Institute of Chemistry, International Center for Chemical Sciences, University of Karachi, Karachi, Pakistan.
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Yousuf S, Latif A, Arfan M, Choudhary MI. 1,2,4-Trimethoxydibenzo[ b, d]furan-3-ol. Acta Crystallogr Sect E Struct Rep Online 2010; 66:o3066. [PMID: 21589376 PMCID: PMC3011800 DOI: 10.1107/s1600536810044417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Accepted: 10/30/2010] [Indexed: 12/03/2022]
Abstract
The title compound, C15H14O5, is a natural product, isolated from Sorbus lanata Syn. Pyrus lanata (D. Don) found in Pakistan. The compound is composed of three spiro-fused rings. The dihedral angle between the mean planes of the benzene rings is 4.81 (13)°. The methoxy groups are oriented at dihedral angles of 74.44 (14), 83.0 (2) and 66.3 (2)° with respect to the planes of the benzene rings to which they are attached. The molecule is consolidated by three intramolecular O—H⋯O and C—H⋯O hydrogen bonds. In the crystal, molecules are linked by intermolecular O—H⋯O hydrogen bonds, forming infinite chains along the b axis.
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Khan R, Malik A, Qadir MI, Adhikari A, Choudhary MI. Phenolic substances of Caragana conferta and their superoxide scavenging activity. Chem Nat Compd 2010. [DOI: 10.1007/s10600-010-9725-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Ali NW, Abouzid S, Nasib A, Khan S, Qureshi J, Choudhary MI. RP-HPLC analysis of withanolides in the flowers, leaves, and roots ofWithania somnifera. ACTA CHROMATOGR 2010. [DOI: 10.1556/achrom.22.2010.3.10] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Abbasi MA, Lodhi MA, Ahmad VU, Choudhary MI. Kinetics studies on the lignan class of natural compounds that inhibits alpha-chymotrypsin. J Asian Nat Prod Res 2009; 11:933-939. [PMID: 20183256 DOI: 10.1080/10286020903321539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The mechanism of inhibition of the alpha-chymotrypsin enzyme by two lignans of the fused bistetrahydrofuran series, epiexcelsin (1) and 5'-demethoxyepiexcelsin (2), which were isolated from the Commiphora mukul Engl., was investigated. Lineweaver-Burk and Dixon plots and their secondary replots showed that these compounds were noncompetitive inhibitors of the enzyme. K(i) values for 1 and 2 were found to be 22.29 +/- 0.015 and 336.30 +/- 0.053 microM, respectively.
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Affiliation(s)
- M A Abbasi
- Department of Chemistry, Center for Natural Product Drug Development, Government College University, Lahore, Pakistan.
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Falodun A, Siraj R, Choudhary MI. GC-MS Analysis of Insecticidal Leaf Essential Oil of Pyrenacantha Staudtii Hutch and Dalz (Icacinaceae). TROP J PHARM RES 2009. [DOI: 10.4314/tjpr.v8i2.44522] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Abouzid S, Elshahaat A, Ali S, Choudhary MI. Antioxidant activity of wild plants collected in Beni-Sueif governorate, Upper Egypt. Drug Discov Ther 2008; 2:286-288. [PMID: 22504722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Antioxidant activity of a selection of commonly occurring wild plants growing in Beni-Sueif governorate, Upper Egypt, has been tested. The plants selected are Tamarix nilotica, Ambrosia maritima, Zygophyllum coccenium, Conyza dioscoridis, Chenopodium ambrosioides, and Calotropis procera. The in vitro antioxidant assays used in this study were 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activity, superoxide anion scavenging activity and iron chelating activity. Extracts prepared from the leaves and flowers of Tamarix nilotica have shown the highest antioxidant activity in the three kinds of assay.
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Affiliation(s)
- S Abouzid
- Department of Pharmacognosy, Faculty of Pharmacy, Beni-Sueif University, Beni-Sueif, Egypt
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Avula B, Begum S, Ahmed S, Choudhary MI, Khan IA. Quantitative determination of vasicine and vasicinone in Adhatoda vasica by high performance capillary electrophoresis. Pharmazie 2008; 63:20-22. [PMID: 18271297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A new method of capillary electrophoresis was developed for the quantitative determination of vasicine and vasicinone from Adhatoda vasica (L.) Nees. The electrophoretic separation was performed using a 47 cm x 50 microm ID (38.5 cm effective length) fused silica capillary. The samples were injected by pressure for 3 s at 50 mbar and the running voltage was 19 kV at the injector end of the capillary. The capillary temperature was maintained at 40 degrees C. The separation of the two alkaloids has been achieved within 11 min with good repeatability. The method was validated in terms of reproducibility, linearity, accuracy and applied for the quantitative determination of vasicine and vasicinone in A. vasica plant samples/extracts. Parameters affecting the resolution such as pH, temperature, organic modifier, buffer concentration and capillary dimensions were reported.
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Affiliation(s)
- B Avula
- National Center for Natural Products Research, University of Mississippi, MS 38677, USA.
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Mbouangouere RN, Tane P, Ngamga D, Djemgou P, Choudhary MI, Ngadjui BT. Piptaderol from Piptadenia africana. Afr J Tradit Complement Altern Med 2007; 4:294-298. [PMID: 20161892 PMCID: PMC2816483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A new glyceryl derivative (Glyceryl-1-hexacosanoate) and a flavone derivative (methyletherapigenin) were isolated from the stem bark extract of Piptadenia africana, a western Cameroonian plant species. Common terpenes like sitosterol, beta-amyrin and eicosane were also isolated. These compounds were identified using physical and spectroscopic methods including mp, IR, (1)H and (13)C-NMR, DEPT, COSY, HMQC, HMBC, EI MS, HREI MS as well as some chemical transformations. The antibacterial activity of the extract, the fractions and the pure compounds is also discussed.
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Affiliation(s)
- R N Mbouangouere
- Department of Chemistry, Faculty of Science, University of Dschang, Box 67 Dschang, Cameroon.
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Wansi JD, Wandji J, Kamdem WAF, Ndom JC, Ngeufa HE, Chiozem DD, Chi Shirri J, Choudhary MI, Tsabang N, Tillequin F, Fomum ZT. Triterpenoids fromDrypetes chevalieriBeille (euphorbiaceae)‡‡. Nat Prod Res 2006; 20:586-92. [PMID: 16835092 DOI: 10.1080/14786410500185451] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The CH2Cl2/CH3OH (1/1) extract of the dried stem of Drypetes chevalieri Beille afforded two new triterpenoïds named drypechevalin A (11-oxo-beta-amyrin-3beta-ylcaffeate) and drypechevalin B (3,7-dioxo-D:A-friedooleanan-24-al) along with five known compounds: lupeol, lupeone, erythrodiol, putranjivadione, friedelin. Their structures were established on the basis of spectroscopic analysis and chemical evidence.
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Affiliation(s)
- J D Wansi
- Faculty of Science, Department of Chemistry, University of Douala, P.O. Box 24157, Douala, Cameroon.
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Malik A, Khan MTH, Khan SB, Ahmad A, Choudhary MI. Tyrosinase inhibitory lignans from the methanol extract of the roots of Vitex negundo Linn. and their structure-activity relationship. Phytomedicine 2006; 13:255-60. [PMID: 16492528 DOI: 10.1016/j.phymed.2004.09.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2004] [Accepted: 09/29/2004] [Indexed: 05/06/2023]
Abstract
Phytochemical investigation of the methanol extract of Vitex negundo afforded eight lignans; negundin A 1, negundin B 2, 6-hydroxy-4-(4-hydroxy-3-methoxy)-3-hydroxymethyl-7-methoxy-3,4-dihydro-2-naphthaledehyde 3, vitrofolal E 4, (+)-lyoniresinol 5, (+)-lyoniresinol-3alpha-O-beta-d-glucoside 6, (+)-(-)-pinoresinol 7, and (+)-diasyringaresinol 8. The structures of these compounds were elucidated unambiguously by spectroscopic methods including 1D and 2D NMR analysis and also by comparing experimental data with literature data. The tyrosinase inhibitory potency of these compounds has been evaluated and attempts to justify their structure-activity relationships have been made in the present work. The compound 5 was found to be the most potent (IC(50)=3.21 microM) while other compounds demonstrated moderate to potent inhibitions. It was found that the substitution of functional group(s) at C-2 and C-3 positions and the presence of the -CH(2)OH group plays a vital role in the potency of the compounds. The compound 5 can act as a potential lead molecule to develop new drugs for the treatment of hyperpigmentation associated with the high production of melanocytes.
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Ghayur MN, Gilani AH, Khan A, Amor EC, Villaseñor IM, Choudhary MI. Presence of calcium antagonist activity explains the use ofSyzygium samarangense in diarrhoea. Phytother Res 2006; 20:49-52. [PMID: 16397921 DOI: 10.1002/ptr.1801] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Syzygium samarangense (Family; Myrtaceae) or 'makopa', as it is commonly known, is native to Malaysia, some islands of Indonesia and to Far East in general. This study was undertaken to rationalize the use of this plant in hypermotility states of the gut. The hexane extract of S. samarangense (Ss.Hex) was found to dose-dependently (10-3000 microg/mL) relax the spontaneously contracting isolated rabbit jejunum. When tested for a possible calcium channel blocking (CCB) activity, the extract (10-1000 microg/mL) relaxed the high K+-induced contractions and also decreased the Ca++ dose-response curves in a dose-dependent manner (30-100 microg/mL), confirming the CCB activity. Four flavonoids isolated from the hexane extract were tested for a possible spasmolytic activity. All flavonoids, identified as: 2'-hydroxy-4',6'-dimethoxy-3'-methylchalcone (SS1), 2',4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone (SS2), 2',4'-dihydroxy-6'-methoxy-3'-methylchalcone (SS3) and 7-hydroxy-5-methoxy-6,8-dimethylflavanone (SS4), showed dose-dependent (10-1000 microg/mL) spasmolytic activity with SS2 being the most potent. These results indicate that the presence of compounds with spasmolytic and calcium antagonist activity may be responsible for the medicinal use of the plant in diarrhoea.
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Affiliation(s)
- M N Ghayur
- Department of Biological and Biomedical Sciences, The Aga Khan University Medical College, Karachi 74800, Pakistan
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Hasan A, Khan KM, Sher M, Maharvi GM, Nawaz SA, Choudhary MI, Supuran CT. Synthesis and inhibitory potential towards acetylcholinesterase, butyrylcholinesterase and lipoxygenase of some variably substituted chalcones. J Enzyme Inhib Med Chem 2005; 20:41-7. [PMID: 15895683 DOI: 10.1080/14756360400015231] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
A series of variably substituted chalcones were synthesized by condensation of substituted acetophenones with mono-, di- or trisubstituded benzaldehydes. It was observed that some of these compounds have the potential to inhibit acetylcholinesterase, whereas others show activity against butyrylcholinesterase, depending on the substitution pattern at the two aromatic rings of these chalcones. Similarly, lipoxygenase was inhibited by two of these compounds. It has been observed that inhibition of the three enzymes was concentration dependent with the IC50 values ranging from 28.2-134.5 microM against acetylcholinesterase, 16.0-23.1 microM against butyrylcholinesterase and 57.6-71.7 microM against lipoxygenase, respectively.
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Affiliation(s)
- Aurangzeb Hasan
- Department of Chemistry, Quaid-i-Azam University, Islamabad-45320, Pakistan
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Choudhary MI, Musharraf SG. Microbial Transformation of Natural Products- A Tool for the Synthesis of Novel Analogues of Bioactive Substances. ACTA ACUST UNITED AC 2005. [DOI: 10.2174/1574089054583830] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Orhan I, Sener B, Choudhary MI, Khalid A. Acetylcholinesterase and butyrylcholinesterase inhibitory activity of some Turkish medicinal plants. J Ethnopharmacol 2004; 91:57-60. [PMID: 15036468 DOI: 10.1016/j.jep.2003.11.016] [Citation(s) in RCA: 164] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2003] [Revised: 10/23/2003] [Accepted: 11/21/2003] [Indexed: 05/24/2023]
Abstract
The chloroform:medianol (1:1) extracts of a number of the plant species belonging to eight families, namely Corydalis solida (L.) Swartz subsp. solida and Glaucium corniculatum (L.) J. H. Rudolph (Papaveraceae), Rhododendron ponticum L. subsp. ponticum and Rhododendron luteum Sweet. (Ericaceae), Buxus sempervirens L. (Buxaceae), Vicia faba L. (Fabaceae), Robinia pseudoacacia L. (Caeselpiniaceae), Tribulus terrestris L. and Zygophyllum fabago L. (Zygophyllaceae), Lycopodium clavatum L. (Lycopodiaceae), Fumaria vaillantii Lois., Fumaria capreolata L., Fumaria kralikii Jordan, Fumaria asepala Boiss., Fumaria densiflora DC., Fumaria flabellata L., Fumaria petteri Reichb. subsp. thuretii (Boiss.) Pugsley, Fumaria macrocarpa Boiss. ex Hausskn., Fumaria cilicica Hauskkn., Fumaria parviflora Lam. and Fumaria judaica Boiss. (Fumariaceae) were screened for their anticholinesterase activity on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes by in vitro Ellman method at 10 microg/ml and 1 mg/ml concentrations. The extracts did not show any noticeable inhibitory activity against both of the enzymes at 10 microg/ml. The extracts of Rhododendron ponticum subsp. ponticum, Rhododendron luteum, Corydalis solida subsp. solida, Glaucium corniculatum, and Buxus sempervirens showed remarkable inhibitory activity above 50% inhibition rate on AChE at 1 mg/ml. Among them, Rhododendron ponticum subsp. ponticum, Corydalis solida subsp. solida and Buxus sempervirens were the most active extracts against BChE having 95.46 +/- 1.03%, 93.08 +/- 0.97%, and 93.45 +/- 0.88% inhibition rates, respectively. Among the extracts screened, all of the Fumaria extracts displayed highly potent inhibition against both of the enzymes at 1 mg/ml concentration compared to the standard.
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Affiliation(s)
- I Orhan
- Department of Pharmacognosy, Faculty of Pharmacy, Gazi University, 06330 Ankara, Turkey.
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Raza M, Shaheen F, Choudhary MI, Sombati S, Rahman AU, DeLorenzo RJ. Inhibition of sustained repetitive firing in cultured hippocampal neurons by an aqueous fraction isolated from Delphinium denudatum. J Ethnopharmacol 2004; 90:367-374. [PMID: 15013203 DOI: 10.1016/j.jep.2003.10.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2002] [Revised: 09/28/2002] [Accepted: 10/20/2003] [Indexed: 05/24/2023]
Abstract
In this report we investigated the effects of the aqueous fraction (AF) isolated from Delphinium denudatum on sustained repetitive firing in cultured neonatal rat hippocampal pyramidal neurons. Blockade of SRF is one of the basic mechanisms of antiepileptic drugs (AED) at the cellular level. The effects of aqueous fraction (0.2-0.6 mg/ml) were compared with the prototype antiepileptic drug, phenytoin (PHT). Using the whole cell current-clamp technique, sustained repetitive firing was elicited in neurons by a depolarizing pulse of 500 ms duration, 0.3 Hz and 0.1-0.6 nA current strength. Similar to phenytoin, aqueous fraction reduced the number of action potentials (AP) per pulse in a concentration-dependent manner until no action potentials were elicited for the remainder of the pulse. There was a corresponding use-dependent reduction in amplitude and Vmax (velocity of upstroke) of action potentials. The Vmax and amplitude of the first action potential was not affected by phenytoin, while aqueous fraction exhibited concentration-dependent reduction. At 0.6 mg/ml aqueous fraction reduced Vmax to 58-63% and amplitude to 16-20% of the control values. The blockade of sustained repetitive firing by aqueous fraction was reversed with hyperpolarization of membrane potential (-65 to -75 mV) while depolarization of membrane potential (-53 to -48 mV) potentiated the block. The results suggest that aqueous fraction blocks sustained repetitive firing in hippocampal neurons in a use-dependent and voltage-dependent manner similar to phenytoin. However, unlike phenytoin, which interacts preferably with the inactive state of the Na+ channel, the compounds present in aqueous fraction apparently also interact with the resting state of the Na+ channels as suggested by dose-dependent reduction of Vmax and amplitude of first AP. We conclude that aqueous fraction contains potent anticonvulsant compounds.
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Affiliation(s)
- Mohsin Raza
- Department of Neurology, Medical College of Virginia, Virginia Commonwealth University, Richmond 23298-599, USA.
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Abstract
One of the most widely used herbs in Ayurvedic medicine is Ashwaghanda, Withania somnifera, a shrub commonly found on the Indian subcontinent. As this plant is increasingly becoming a popular adaptogenic in the western world, analytical methods for its identification and quality control are in demand. Thus, a HPLC method for the determination of withaferin A and withanolide D was developed. The system was successfully used to investigate the presence of the markers in different W. somnifera plant parts as well as to analyze their content in market products.
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Affiliation(s)
- M Ganzera
- Department of Pharmacognosy, University of Innsbruck, Innsbruck 6020, Austria.
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Raza M, Shaheen F, Choudhary MI, Rahman AU, Sombati S, Suria A, Rafiq A, DeLorenzo RJ. Anticonvulsant effect of FS-1 subfraction isolated from roots of Delphinim denudatum on hippocampal pyramidal neurons. Phytother Res 2003; 17:38-43. [PMID: 12557245 DOI: 10.1002/ptr.1072] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The effects were investigated of a partially purified subfraction (FS-1) isolated from Delphinium denudatum on sustained repetitive firing (SRF) of cultured neonatal rat hippocampal pyramidal neurons. The blockade of sustained repetitive firing is one of the basic mechanisms of antiepileptic drugs at the cellular level. Using the whole cell current-clamp technique, sustained repetitive firing was elicited in pyramidal neurons under study by a depolarizing pulse of 500 ms duration, 0.3 Hz and 0.1-0.6 nA current strength. FS-1 (0.01-0.06 mg/mL) reduced the number of action potentials per pulse in a dose-dependent manner until no action potentials were elicited for the remainder of the pulse. There was a corresponding use-dependent reduction in amplitude and Vmax of action potentials. The Vmax of action potential 1 exhibited a dose-dependent reduction. At a dose of 0.06 mg/mL FS-1 reduced Vmax to 29%-38% and amplitude to 16%-20 % of the control values. The blockade of sustained repetitive firing by FS-1 was reversed by hyperpolarization of the membrane potential (-65 to -75 mV) while depolarization of the membrane potential (-53 mV to -48 mV) potentiated the block. The results suggest that FS-1 blocks sustained repetitive firing in hippocampal neurons in a use-dependent and voltage-dependent manner similar to the prototype anticonvulsant drug, phenytoin. However, unlike phenytoin, which binds preferably to the inactive state, the compounds present in FS-1 also interacted with the resting state of the Na+ channels by reducing Vmax of action potential 1. The results indicate that the partially purified FS-1 subfraction of Delphinium denudatum contains a potent anticonvulsant compound.
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Affiliation(s)
- Mohsin Raza
- Department of Neurology, Medical College of Virginia, Virginia Commonwealth University, PO Box 980599, Richmond, VA 23298-0599, USA
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Raza M, Shaheen F, Choudhary MI, Rahman AU, Sombati S, DeLorenzo RJ. In vitro inhibition of pentylenetetrazole and bicuculline-induced epileptiform activity in rat hippocampal pyramidal neurons by aqueous fraction isolated from Delphinium denudatum. Neurosci Lett 2002; 333:103-6. [PMID: 12419491 DOI: 10.1016/s0304-3940(02)01027-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Roots of Delphinium denudatum W. are used for the treatment of epilepsy by traditional healers in subcontinent. Aqueous fraction (AF) isolated from D. denudatum has previously shown significant anticonvulsant activity in in vivo and in vitro models of seizures. We investigated anticonvulsant effects of AF on pentylenetetrazole (PTZ) and bicuculline (BIC)-induced epileptiform activity in primary hippocampal neuronal cultures. Electrophysiological studies on single pyramidal neurons were carried out by using whole-cell current clamp technique. Introduction of AF (0.6 mg/ml) in perfusate blocked PTZ (10 mM) and BIC (100 micro M)-induced epileptiform activity comprising of paroxysmal depolarization shifts (PDS). The PDS were elicited again when AF was removed from perfusate. We conclude that AF contains anticonvulsant compounds that possibly interact with GABA(A) receptor to produce blockade of epileptiform activity. Further studies on isolation of compounds from AF may lead to discovery of new class of anticonvulsants.
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Affiliation(s)
- Mohsin Raza
- Department of Neurology, Medical College of Virginia, Virginia Commonwealth University, P O Box 980599, Richmond, VA 23298-0599, USA.
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Abstract
Studies on enzyme inhibition remain an important area of pharmaceutical research since these studies have led to the discoveries of drugs useful in a variety of physiological conditions. The enzyme inhibitors can interact with enzymes and block their activity towards natural substrates. Urease inhibitors have recently attracted much attention as potential new anti-ulcer drugs. Ironically, urease was the first enzyme crystallized but its mechanism of action is still largely misunderstood. This chapter therefore reviews comprehensive developments in the field of urease inhibitors. Inhibitors of urease can be broadly classified into two categories: (1) active site directed (substrate-like), (2) mechanism-based directed. We present here the examples of selected inhibitors along with their mechanisms of action to characterize their mode of urease inhibition. The observations that urease due to its high substrate (urea) specificity can only bind to a few inhibitors with a similar binding mode as urea is also discussed. Several non-covalent interactions including hydrogen bonds and hydrophobic contacts stabilize the enzyme-inhibitor complex. Regardless of the class of compound, it is reported that only a few functional groups with electronegative atoms such as oxygen, nitrogen and sulfur act either as bidentate (mostly), tridentate (rarely), or as ligand-chelator to form octahedral complexes with two slightly distorted octahedral Ni ions of the enzyme. Bulky groups attached to the pharmacophore were found to decrease the activity of inhibitors, since the lack of a bulky attachment makes it easier for urease inhibitors to enter the substrate-binding pocket as well as avoid unfavorable steric interactions with amino acid residues in its vicinity. This review is intended to provide highlights of the inhibition of urease by hydroxamic acids (HXAs), phosphorodiamidates (PPDs), imidazoles, phosphazene and related compounds. These compounds are compared to previously reported urease inhibitors for the catalytic models proposed for urease activity. The differences in inhibition of urease activities from plants and of bacterial origin by various inhibitors and physiological implications of urease inhibition are discussed.
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Affiliation(s)
- Z Amtul
- HEJ Research Institute of Chemistry, International Center for Chemical Sciences, University of Karachi, Karachi, 75720, Pakistan
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Jayasinghe UL, Kumarihamya BM, Nadeemb M, Choudhary MI, Weerasooriya A. Iso-N-formyl-5-en-chonemorphine, a steroidal alkaloid from Sarcococca zeylanica. Nat Prod Lett 2002; 15:151-5. [PMID: 11858546 DOI: 10.1080/10575630108041274] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Chemical investigation of the non-quaternary alkaloidal fraction of the aerial parts of Sarcococca zeylanica of the family Buxaceae furnished a steroidal alkaloid iso-N-formyl-5-en-chonemorphine, which has not been previously reported as a natural product. The structure of this alkaloid was established on the basis of spectroscopic evidence.
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Sultanova N, Makhmoor T, Abilov ZA, Parween Z, Omurkamzinova VB, ur-Rahman A, Choudhary MI. Antioxidant and antimicrobial activities of Tamarix ramosissima. J Ethnopharmacol 2001; 78:201-205. [PMID: 11694365 DOI: 10.1016/s0378-8741(01)00354-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The ethylacetate and water-acetone extracts of Tamarix ramosissima were screened for their antioxidant, antibacterial, antifungal and DNA damaging activities through in vitro experiments. All fractions as well as precipitates showed significant antioxidant activity. A known compound tamarixetin (1) was isolated which showed significant DNA damaging activity in mutant yeast bioassay. Results revealed that antioxidant and antibacterial activities were associated with the presence of polyphenolic substances.
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Affiliation(s)
- N Sultanova
- Department of Chemistry, Al-Farabi, Kazakh State National University, Karasay Batir-95.A, Almaty, Kazakhstan
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Abstract
The 1.8 A crystal structure of 7-hydroxycoumarin (7-HC) bound to chymotrypsin reveals that this inhibitor forms a planar cinnamate acyl-enzyme complex. The phenyl ring of the bound inhibitor forms numerous van der Waals contacts in the S1 pocket of the enzyme, with the p-hydroxyl group donating a hydrogen bond to the main-chain oxygen atom of Ser217, and the o-hydroxyl group forming a water-mediated hydrogen bond with the carbonyl oxygen of Val227. The structure of the acyl-enzyme complex suggests that the mechanism of inhibition of 7-HC involves nucleophilic attack by the Ser195 O(gamma) atom on the carbonyl carbon atom of the inhibitor, accompanied by the breaking of the 2-pyrone ring of the inhibitor, and leading to the formation of a cinnamate acyl-enzyme derivative via a tetrahedral transition state. Comparisons with structures of photoreversible cinnamates bound to chymotrypsin reveal that although 7-HC interacts with the enzyme in a similar fashion, the binding of 7-HC to chymotrypsin takes place in a productive conformation in contrast to the photoreversible cinnamates. In summary, the 7-HC-chymotrypsin complex provides basic insight into the inhibition of chymotrypsin by natural coumarins and provides a structural basis for the design of more potent mechanism-based inhibitors against a wide range of biologically important chymotrypsin-like enzymes.
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Affiliation(s)
- U Ghani
- International Centre for Chemical Sciences, H. E. J. Research Institute of Chemistry, University of Karachi, Karachi, 75270, Pakistan
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Raza M, Shaheen F, Choudhary MI, Sombati S, Rafiq A, Suria A, Rahman A, DeLorenzo RJ. Anticonvulsant activities of ethanolic extract and aqueous fraction isolated from Delphinium denudatum. J Ethnopharmacol 2001; 78:73-78. [PMID: 11585691 DOI: 10.1016/s0378-8741(01)00327-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Dried roots of Delphinium denudatum Wall. are a popular folk remedy for the treatment of epilepsy in the traditional Unani system of medicine in the sub-continent. We carried out anticonvulsant screening of the ethanolic extract (EE) and aqueous fraction (AF) of this plant utilising the maximal electroshock (MEST) and subcutaneous pentylenetetrazole (scPTZ), bicuculline (scBIC), picrotoxin (scPTX) and strychnine (scSTN) tests for anticonvulsant activity. EE had weak dose-dependent anticonvulsant effects on seizures induced by PTZ and BIC. AF exhibited dose-dependent activity against hind limb tonic extension phase (HLTE) of MEST and comparatively stronger anticonvulsant activity against seizures induced by PTZ and BIC. The results suggest the presence of potent anticonvulsant compounds in AF of D. denudatum and deserve further investigation for isolation of active compounds and elucidation of the mechanism of anticonvulsant action.
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Affiliation(s)
- M Raza
- Department of Neurology, Medical College of Virginia, Virginia Commonwealth University, P.O. Box 980599, Richmond, VA 23298-0599, USA
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Parveen S, Khalid A, Farooq A, Choudhary MI. Acetyl and butyrylcholinesterase-inhibiting triterpenoid alkaloids from Buxus papillosa. Phytochemistry 2001; 58:963-968. [PMID: 11684196 DOI: 10.1016/s0031-9422(01)00332-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Three triterpenoid alkaloids, buxakashmiramine [(20S)-20-dimethylamino-4',6'-dimethoxy-5'-hydroxybenzoylamino-3beta-methyl-buxan-31-ol] (1), buxakarachiamine [(20S)-20-dimethylamino-2'-hydroxy-3beta-methyl-3'-methyl-butanoylamino-9,10-seco-buxa-9(11), 10(19)-dien-31-ol] (2) and buxahejramine [(20S)-20-dimethylamino-2'-hydroxy-3beta-methyl-3'-methyl-pentanoylamino-9,10-seco-buxa-9(11), 10(19)-dien-31-ol] (3) were isolated from the leaves of Buxus papillosa. Four known bases, cycloprotobuxine-C (4), cyclovirobuxeine-A (5), cyclomicrophylline-A (6) and semperviraminol (7) were isolated for the first time from this species. Their structures were established through extensive spectroscopic studies. Most of these compounds exhibited anticholinesterase activity.
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Choudhary MI, Nur-E-Alam M, Akhtar F, Ahmad S, Baig I, Ondögnii P, Gombosurengyin P. Five new peltogynoids from underground parts of Iris bungei: a Mongolian medicinal plant. Chem Pharm Bull (Tokyo) 2001; 49:1295-8. [PMID: 11605657 DOI: 10.1248/cpb.49.1295] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Five new peltogynoids, irisoids A-E (1-5), have been isolated from the underground parts of Iris bungei. The structures of the new compounds were established on the basis of spectroscopic methods and were found to be 1,8,10-trihydroxy-9-methoxy-[1]benzopyrano-[3,2-c][2]-benzopyran-7(5H)-one (1), 1,8-dihydroxy-9,10-dimethoxy-[1]benzopyrano-[3,2-c][2]-benzopyran-7(5H)-one (2), 1,10-dihydroxy-8,9-dimethoxy-[1]benzopyrano-13,2-c][2]-benzopyran-7(5H)-one (3), 1,8-dihydroxy-9,10-methylenedioxy-[1]benzopyrano-[3,2-c][2]-benzopyran-7(5H)-one (4), and 1,8,11-trihydroxy-9,10-methylenedioxy-[1]benzopyrano-[3,2-c][2]-benzopyran-7(5H)-one (5). The structure of irisoid B (2) was established unambiguously by X-ray diffraction study.
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Affiliation(s)
- M I Choudhary
- HEJ Research Institute of Chemistry, University of Karachi, Pakistan.
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Raza M, Shaheen F, Choudhary MI, Suria A, Rahman AU, Sombati S, DeLorenzo RJ. Anticonvulsant activities of the FS-1 subfraction isolated from roots of Delphinium denudatum. Phytother Res 2001; 15:426-30. [PMID: 11507736 DOI: 10.1002/ptr.792] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Delphinium denudatum Wall. (Ranunculaceae) is a medicinal herb used for the treatment of epilepsy in the subcontinent. The present study reports the anticonvulsant activities in the maximal electroshock test (MEST) and subcutaneous pentylenetetrazole (PTZ), bicuculline (BIC), picrotoxin (PIC)-induced seizures of the FS-1 subfraction (FS-1) that was obtained by purification of an aqueous fraction isolated from the roots of D. denudatum. In CF 1 mice, FS-1 (600 mg/kg i.p.) exhibited very potent anticonvulsant activity that was comparable to the effects of the well-known antiepileptic drug phenytoin (20 mg/kg) in MEST and protected 100% animals from hind limb tonic extension phase of this model. FS-1 also suppressed PTZ-induced threshold seizure and the loss of the righting reflex with tonic fore and hind limb extension by 100%, similar to the antiepileptic drug valproic acid (350 mg/kg). BIC-induced seizures were suppressed in 80% of the animals. FS-1 exhibited weak anticonvulsant effect on PIC-induced seizures, however, it significantly reduced mortality and delayed the onset of seizures. FS-1 had no effect on strychnine (STN)-induced extensor seizures. The results demonstrate the broad and potent anticonvulsant activity of the compounds in FS-1 of D. denudatum.
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Affiliation(s)
- M Raza
- Department of Neurology, Medical College of Virginia, Virginia Commonwealth University, PO Box 980599, Richmond, VA 23298-0599, USA
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Choudhary MI, Nur-e-Alam M, Baig I, Akhtar F, Khan AM, Badarchiin T, Purevsuren G, Nahar N. Four new flavones and a new isoflavone from Iris bungei. J Nat Prod 2001; 64:857-860. [PMID: 11473411 DOI: 10.1021/np000560b] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Four new irisflavones A-D (1-4) and irilin D (5) have been isolated from the underground parts of Iris bungei along with known isoflavones, irilins A-B (6-7) and tlatancuayin (8). The structures of the new compounds were determined using NMR and mass spectroscopic methods and were found to be 2',5,7-trihydroxy-3,6-dimethoxyflavone (1), 2',5-dihydroxy-3,6,7-trimethoxyflavone (2), 2',5,6'-trihydroxy-3,6,7-trimethoxyflavone (3), 3,3',5-trihydroxy-2',7-dimethoxyflavone (4), and 3',4',5,7-tetrahydroxy-6-methoxyisoflavone (5). The structures of irisflavones 1, 3, and 4 were confirmed by single-crystal X-ray diffraction studies.
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Affiliation(s)
- M I Choudhary
- H. E. J. Research Institute of Chemistry, International Center for Chemical Sciences, University of Karachi, Karachi-75270, Pakistan.
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Kalauni SK, Choudhary MI, Shaheen F, Manandhar MD, Gewali MB, Khalid A. Steroidal alkaloids from the leaves of Sarcococca coriacea of Nepalese origin. J Nat Prod 2001; 64:842-844. [PMID: 11421762 DOI: 10.1021/np000466v] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Two new steroidal alkaloids, (-)-vaganine D (1) [(20S)-20-(N,N-dimethylamino)-3 beta-(senecioylamino)-5 alpha-pregn-16-en-4 beta-yl acetate], and (+)-nepapakistamine A (2) [(20S)-20-(N-methylamino)-3 beta-(tigloylamino)-5 alpha-pregn-16-en-2 beta,4 beta-diacetate], were isolated from the leaves of Sarcococca coriacea. Their structures were elucidated on the basis of their spectral properties. Compounds 1 and 2 were found to be cholinesterase inhibitors.
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Affiliation(s)
- S K Kalauni
- Central Department of Chemistry, Tribhuvan University, Kirtipur, Kathmandu, Nepal
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Ngounou FN, Choudhary MI, Malik S, Makhmoor T, Nur-E-Alam M, Zareen S, Lontsi D, Ayafor JF, Sondengam BL. New antioxidant and antimicrobial ellagic acid derivatives from Pteleopsis hylodendron. Planta Med 2001; 67:335-339. [PMID: 11458450 DOI: 10.1055/s-2001-14306] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Bioassay-guided isolation of two new compounds, 3,4-methylenedioxy-3'-O-methyl-4'-O-glucoside ellagic acid (1) and the pteleoellagic acid derivative (2), from the stem bark of Pteleopsis hylodendron is reported along with 3,4-methylenedioxy-3'-O-methyl ellagic acid (3), 3,3'-di-O-methyl ellagic acid (4) and 3,3',4'-tri-O-methyl ellagic acid (5), which were obtained for the first time from this plant. The structures of these compounds were elucidated with the help of spectroscopic studies. Compounds 1 and 4 were found to have significant antioxidant activity, while compounds 1-4 showed antibacterial activity against different pathogenic bacteria.
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Abstract
Two new aurones, 4'-chloro-2-hydroxyaurone (1) and 4'-chloroaurone (2) were isolated from Spatoglossum variabile. The structures of these compounds were elucidated by modern spectroscopic techniques.
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Affiliation(s)
- Atta-ur-Rahman
- International Center for Chemical Sciences, H. E. J. Research Institute of Chemistry, University of Karachi, Pakistan.
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Abstract
The roots of Aconitum falconeri have yielded two new norditerpenoid alkaloids, faleoconitine (1) and 3'-methoxyacoforestinine (2) along with the known compounds, karakoline, 3-hydroxy-2-methyl-4H-pyran-4-one, and 3,4-dimethoxymethylbenzoate, which have been isolated for the first time from this plant. The previously reported pseudaconitine (3) was also isolated. Compounds 1 and 3 were found to be moderate inhibitors of the enzyme acetylcholinesterase.
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Abstract
Five new pregnane-type steroidal alkaloids (1-5) have been isolated from Sarcococca saligna. A combination of UV, IR, MS, and 1D and 2D NMR spectroscopic studies established their structures as salignarine A [(20S)-2beta-hydroxy-4beta-acetoxy-5alpha, 6alpha-epoxy-20-(dimethylamino)-3beta-(tigloylamino)pregnane ] (1), salignarine B [(20S)-2beta-hydroxy-20-(dimethylamino)-3beta-(tigloylamino) -pregn-5- ene] (2), salignarine C [(20S)-2beta-hydroxy-20-(dimethylamino)-3beta-(senecioylamino++ +)-pregn- 5-ene] (3), salignarine D [(20S)-20-(dimethylamino)-3beta-(senecioylamino)-5alpha-preg n-16-ene] (4), and salignarine E [(20S)-20-(dimethylamino)-3beta-(tigloylamino)-pregn-4-ene] (5), respectively.
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Jayasinghe ULB, Nadeem M, Atta-Ur-Rahman, Choudhary MI. 11-Hydroxyepipachysamine-E, A New Steroidal Alkaloid fromSarcococca brevifolia. ACTA ACUST UNITED AC 2000. [DOI: 10.1080/10575630008041245] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Ahmad VU, Yasmeen S, Ali Z, Khan MA, Choudhary MI, Akhtar F, Miana GA, Zahid M. Taraxacin, a new guaianolide from Taraxacum wallichii. J Nat Prod 2000; 63:1010-1. [PMID: 10924189 DOI: 10.1021/np990495+] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
A new guaianolide, taraxacin (1), and a known sesquiterpene ketolactone (2) have been isolated from an ethyl acetate-soluble part of a methanolic extract of Taraxacum wallichii. The structure of 1 was established using NMR, MS, and X-ray crystallographic methods. The (13)C NMR data of 2 is also being reported for the first time.
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Affiliation(s)
- V U Ahmad
- H.E.J. Research Institute of Chemistry, University of Karachi, Karachi-75270, Pakistan.
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