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Katharigatta N Venugopala, 1, 2 Christophe Tratrat, 1 Melendhran Pillay, 3 Sandeep Chandrashekharappa, 4 Omar Husham Ahmed Al-Attraqchi, 5 Bandar E Aldhubiab, 1 Mahesh Attimarad, 1 Osama I Alwassil, 6 Anroop B Nair, 1 Nagaraja Sreeharsha, 1 Rashmi Venugopala, 7 Mohamed A Morsy, 1, 8 Michelyne Haroun, 1 Hezekiel M Kumalo, 9 Bharti Odhav, 2 Koleka Mlisana 3 1Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Kingdom of Saudi Arabia; 2Department of Biotechnology and Food Technology, Durban University of Technology, Durban 4001, South Africa; 3Department of Microbiology, National Health Laboratory Services, KZN Academic Complex, Inkosi Albert Luthuli Central Hospital, Durban 4001, South Africa; 4Institute for Stem Cell Biology and Regenerative Medicine, NCBS, TIFR, Bangalore 560 065, India; 5Department of Pharmaceutical Sciences, Faculty of Pharmacy, Philadelphia University, Amman 19392, Jordan; 6Department of Pharmaceutical Sciences, College of Pharmacy, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia; 7Department of Public Health Medicine, University of KwaZulu-Natal, Howard College Campus, Durban 4001, South Africa; 8Department of Pharmacology, Faculty of Medicine, Minia University, El-Minia 61511, Egypt; 9Department of Medical Biochemistry, School of Laboratory Medicine and Medical Sciences, University of KwaZulu-Natal, Medical School, Durban 4001, South AfricaCorrespondence: Katharigatta N VenugopalaDepartment of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, P.o. Box-400, Al-Ahsa 31982, Kingdom of Saudi ArabiaTel +96613 589 8842Email kvenugopala@kfu.edu.saSandeep ChandrashekharappaInstitute for Stem Cell Biology and Regenerative Medicine, National Center for Biological Sciences, Tata Institute of Fundamental Research, GKVK, Bellary Road, Bangalore 560 065, IndiaTel +9194486 39413Email sandeepc@instem.res.inBackground and Purpose: Tuberculosis has been reported to be the worldwide leading cause of death resulting from a sole infectious agent. The emergence of multidrug-resistant tuberculosis and extensively drug-resistant tuberculosis has made the battle against the infection more difficult since most currently available therapeutic options are ineffective against these resistant strains. Therefore, novel molecules need to be developed to effectively treat tuberculosis disease. Preliminary docking studies revealed that tetrahydropyrimidinone derivatives have favorable interactions with the thymidylate kinase receptor. In the present investigation, we report the synthesis and the mycobacterial activity of several pyrimidinones and pyrimidinethiones as potential thymidylate kinase inhibitors.Methods: The title compounds ( 1a–d) and ( 2a–b) were synthesized by a one-pot three-component Biginelli reaction. They were subsequently characterized and used for whole-cell anti-TB screening against H37Rv and multidrug-resistant (MDR) strains of Mycobacterium tuberculosis (MTB) by the resazurin microplate assay (REMA) plate method. Molecular modeling was conducted using the Accelry’s Discovery Studio 4.0 client program to explain the observed bioactivity of the compounds. The pharmacokinetic properties of the synthesized compounds were predicted and analyzed.Results: Of the compounds tested for anti-TB activity, pyrimidinone 1a and pyrimidinethione 2a displayed moderate activity against susceptible MTB H37Rv strains at 16 and 32 μg/mL, respectively. Only compound 2a was observed to exert modest activity at 128 μg/mL against MTB strains with cross-resistance to rifampicin and isoniazid. The presence of the trifluoromethyl group was essential to retain the inhibitory activity of compounds 1a and 2a. Molecular modeling studies of these compounds against thymidylate kinase targets demonstrated a positive correlation between the bioactivity and structure of the compounds. The in-silico ADME (absorption, distribution, metabolism, and excretion) prediction indicated favorable pharmacokinetic and drug-like properties for most compounds.Conclusion: Pyrimidinone 1a and pyrimidinethione 2a were identified as the leading compounds and can serve as a starting point to develop novel anti-TB therapeutic agents.Keywords: thymidylate kinase inhibitors, tetrahydropyrimidinones, tetrahydropyrimidinethiones, multidrug resistance, Mycobacterium tuberculosis, molecular modeling

Katharigatta N Venugopala,1,2 Reshme Govender,2 Mohammed A Khedr,1,3 Rashmi Venugopala,4 Bandar E Aldhubiab,1 Sree Harsha,1 Bharti Odhav2 1Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa, Kingdom of Saudi Arabia; 2Department of Biotechnology and Food Technology, Durban University of Technology, Durban, South Africa; 3Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Helwan University, Ein Helwan, Cairo, Egypt; 4Department of Public Health Medicine, University of KwaZulu-Natal, Howard College Campus, Durban, South Africa Abstract: Dihydropyrimidine scaffold has a wide range of potential pharmacological activities such as antiviral, antitubercular, antimalarial, anti-inflammatory, and anticancer properties. 5-Lipoxygenase enzyme is an enzyme responsible for the metabolism of arachidonic acid to leukotrienes. The elevated levels of this enzyme and its metabolites in cancer cells have a direct relation on the development of cancer when compared to normal cells. The development of novel lipoxygenase inhibitors can have a major role in cancer therapy. A series of substituted 1,4-dihydropyrimidine analogues were synthesized and characterized by 1H-NMR, 13C-NMR, and HRMS. Molecular docking against lipoxygenase enzyme (protein data bank code =3V99) was done using Molecular Operating Environment 2013.08 and Leadit 2.1.2 softwares and showed high affinities. The synthesized compounds were tested for their lipoxygenase inhibitory activity and showed inhibition ranging from 59.37%±0.66% to 81.19%±0.94%. The activity was explained by a molecular docking study. The title compounds were also tested for cytotoxic activity against two human cancer cell lines Michigan Cancer Foundation-7 and human melanoma cells and a normal peripheral blood mononuclear cell line. Keywords: 1,4-dihydropyrimidines, synthesis and characterization, molecular docking study

In this study, Fusarium species isolated from 29 patients with mycotic keratitis were identified and tested for their ability to produce mycotoxins. Members of the F. solani species complex ( Fs complex) were the predominant species isolated, followed by F. verticillioides, F. dimerum, members of the F. oxysporum species complex Fo complex), F. incarnatum, F. chlamydosporum and F. lateritium. Of these, 76% of the Fusarium isolates produced fusaric acid, moniliformin or fumonisin B1. Many of the fusaria isolated are common aetiological agents of mycotic keratitis infections. However, F. incarnatum, F. chlamydosporum and F. lateritium have previously not been found in this infection. These findings indicate that a greater variety of fusarial species are becoming associated with mycotic keratitis infections. This paper further demonstrates the mycotoxin-producing ability of these clinical isolates and assesses cellular cytotoxicity. [ABSTRACT FROM AUTHOR]

An externally unskinned polysulfone ultrafiltration capillary membrane was used as an immobilisation matrix for the white rot basidiomycete Phanerochaete chrysosporium ME446. In this study, different membrane bioreactor configurations, scanning electron microscopy, atomic force microscopy and enzyme assays were used to characterise the spatial distribution of spores after immobilisation by reverse filtration and document the subsequent growth phases. A single capillary membrane bioreactor was also used to develop and evaluate a spore immobilisation technique by modifying conventional bioreactor configurations for reverse filtration onto the external surface of the membrane. Results indicate that spore immobilisation was dependent on a differential pressure across the tube wall and the fluid flow pattern in the tube, thus influencing the spatial distribution of spores along the surface and within the microvoids in the membrane wall. The resultant radial and lateral biofilm development using this reverse filtration approach promoted uniform biomass development, which favoured manganese peroxidase production. [Copyright &y& Elsevier]

Novel series of diversely substituted indolizines were designed, synthesized, and evaluated for their in vitro anti-mycobacterial activity against H37Rv and multi-drug-resistant (MDR) strains of Mycobacterium tuberculosis (MTB). Many compounds exhibited significant inhibitory activity against MTB H37Rv strains. Indolizines 2d, 2e, and 4 were also found to be active against MTB clinical isolates with multi-resistance to rifampicin and isoniazid. Indolizine 4 was identified as the most promising anti-mycobacterial agent, displaying minimum inhibitory concentration (MIC) values of 4 and 32 μg/mL against H37Rv and MDR strains, respectively. Furthermore, an in silico study was carried out for prospective molecular target identification and revealed favorable interactions with the target enzymes CYP 121, malate synthase, and DNA GyrB ATPase. None of the potent molecules presented toxicity against peripheral blood mononuclear (PBM) cell lines, demonstrating their potentiality to be used for drug-sensitive and drug-resistant tuberculosis therapy.

The cyclooxygenase-2 (COX-2) enzyme is considered to be an important target for developing novel anti-inflammatory agents. Selective COX-2 inhibitors offer the advantage of lower adverse effects that are commonly associated with non-selective COX inhibitors. In this work, a novel series of methyl 3-(substituted benzoyl)-7-substituted-2-phenylindolizine-1-carboxylates was synthesized and evaluated for COX-2 inhibitory activity. Compound 4e was identified as the most active compound of the series with an IC 50 of 6.71 M, which is comparable to the IC 50 of indomethacin, a marketed non-steroidal anti-inflammatory drug (NSAID). Molecular modeling and crystallographic studies were conducted to further characterize the compounds and gain better understanding of the binding interactions between the compounds and the residues at the active site of the COX-2 enzyme. The pharmacokinetic properties and potential toxic effects were predicted for all the synthesized compounds, which indicated good drug-like properties. Thus, these synthesized compounds can be considered as potential lead compounds for developing effective anti-inflammatory therapeutic agents., Competing Interests: The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

Indolizines are heteroaromatic compounds, and their synthetic analogues have reportedly showed promising pharmacological properties. In this study, a series of synthetic 7-methoxy-indolizine derivatives were synthesised, characterised and evaluated for in vitro whole-cell anti-tuberculosis (TB) screening against susceptible (H37Rv) and multi-drug-resistant (MDR) strains of Mycobacterium tuberculosis (MTB) using the resazurin microplate assay method. The cytotoxicity was evaluated using the MTT assay. In silico molecular-docking study was conducted for compounds 5a-j against enoyl-[acyl-carrier] protein reductase, a key enzyme of the type II fatty acid synthesis that has attracted much interest for the development of novel anti-TB compounds. Thereafter, molecular dynamic (MD) simulation was undertaken for the most active inhibitors. Compounds 5i and 5j with the methoxy functional group at the meta position of the benzoyl group, which was at the third position of the indolizine nucleus, demonstrated encouraging anti-TB activity against MDR strains of MTB at 16 μg/mL. In silico studies showed binding affinity within the range of 7.07-8.57 kcal/mol, with 5i showing the highest binding affinity. Hydrogen bonding, π-π- interactions, and electrostatic interactions were common with the active site. Most of these interactions occurred with the catalytic amino acids (Pro193, Tyr158, Phe149, and Lys165). MD simulation showed that 5j possessed the highest binding affinity toward the enzyme, according to the two calculation methods (MM/PBSA and MM/GBSA). The single-crystal X-ray studies of compounds 5c and 5d revealed that the molecular arrangements in these two structures were mostly guided by C-H···O hydrogen-bonded dimeric motifs and C-H···N hydrogen bonds, while various secondary interactions (such as π···π and C-H···F) also contributed to crystal formation. Compounds 5a, 5c, 5i, and 5j exhibited no toxicity up to 500 μg/mL. In conclusion, 5i and 5j are promising anti-TB compounds that have shown high affinity based on docking and MD simulation results., Competing Interests: The authors have declared that no competing interests exist.

Biotin is very important for the survival of Mycobacterium tuberculosis. 7,8-Diamino pelargonic acid aminotransaminase (DAPA) is a transaminase enzyme involved in the biosynthesis of biotin. The benzothiazole title compounds were investigated for their in vitro anti-tubercular activity against two tubercular strains: H37Rv (ATCC 25,177) and MDR-MTB (multidrug-resistant M. tuberculosis, resistant to isoniazid, rifampicin, and ethambutol) by an agar incorporation method. The possible binding mode and predicted affinity were computed using a molecular docking study. Among the synthesized compounds in the series, the title compound {2-(benzo[d]thiazol-2-yl-methoxy)-5-fluorophenyl}-(4-chlorophenyl)-methanone was found to exhibit significant activity with minimum inhibitory concentrations of 1 μg/mL and 2 μg/mL against H37Rv and MDR-MTB, respectively; this compound showed the highest binding affinity (-24.75 kcal/mol) as well.

Background: Benzothiazole derivatives are known for anti-TB properties. Based on the known anti-TB benzothiazole pharmacophore, in the present study, we described the synthesis, structural elucidation, and anti-tubercular screening of a series of novel benzothiazole (BNTZ) derivatives (BNTZ 1-7 and BNTZ 8-13)., Objective: The study aims to carry out the development of benzothiazole based anti-TB compounds., Methods: Title compounds are synthesized by microwave method and purified by column chromatography. Characterization of the compounds is achieved by FT-IR, NMR (1H and 13C), LCMS and elemental analysis. Screening of test compounds for anti-TB activity is achieved by Resazurin Microplate Assay (REMA) Plate method., Results: It was noted that the BNTZ compound with an isoquinoline nucleus (BNTZ 9) exhibited remarkable anti-tubercular activity at 8 µg/mL against both the susceptible strain H37Rv and the multi-drug resistant tuberculosis strains of Mycobacterium tuberculosis. On the other hand, the BNTZ compound with a naphthalene nucleus (BNTZ 2) revealed anti-tubercular activity at 6 µg/mL and 11 µg/mL against both the susceptible strain H37Rv and the multi-drug resistant tuberculosis strains of M. tuberculosis, respectively. One of the selected BNTZ derivatives BNTZ 13 was used for single crystal X-ray studies., Conclusion: To identify the appropriate target for potent BNTZ compounds from the series, molecular modeling studies revealed the multiple strong binding of several BNTZs with mycobacterium lysine-ɛ-aminotransferase and decaprenyl-phosphoryl-β-D-ribose 2'-oxidase. The interaction is derived by forming favorable hydrogen bonds and stacking interactions. This new class of BNTZ compounds gave promising anti-tubercular actions in the low micromolar range, and can be further optimized on a structural basis to develop promising, novel, BNTZ pharmacophore-based anti-tubercular drugs., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

A series of methyl or ethyl 4-(substitutedphenyl/pyridyl)-6-methyl-2-oxo/thioxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate (HPM) analogues 4a-g were synthesized and evaluated for larvicidal activity against Anopheles arabiensis. These newly synthesized compounds were characterized by spectral studies such as FT-IR, NMR ( 1 H and 13 C), LC-MS, and elemental analysis. The conformational features and supramolecular assembly of molecules 4a, 4b, and 4e were further analyzed from single crystal X-ray study. The larvicidal activity of these tetrahydropyrimidine pharmacophore series was analyzed based on their relative substituents. Among the synthesized HPM analogous from the series, compounds 4d and 4e both having electron withdrawing chlorine group on phenyl ring at the fourth position of the tetrahydropyrimidine pharmacophore exhibited the most promising larvicidal activity., (© 2018 John Wiley & Sons A/S.)

Introduction: The traditional method of producing instant foods involves producing a gelatinised paste from the preferred grain flour and proceeding to dry it using a drum drier. This produced a flaked product, which can be used as is or ground and sieved to obtain the desired particle size. With the advent of extrusion cooking technology and diverse production processes associated with the technology, food products including instant foods from cereals were developed., Objectives: The primary objective of this study was to produce a nutritious and acceptable pearl millet instant beverage powder (PMIBP) using combination processing., Methods: The effect of different processing methods (malting, extrusion, and a combination of both processes) on the nutritional, biochemical, and sensory characteristics of beverage powders and beverages made from two varieties of pearl millet (Pennisetum glaucum) were evaluated., Results: Combination processing led to a significant (p ≤ 0.05) decrease in total fat and total dietary fibre (TDF) (3.85 and 22.99 g/100 g, respectively) of AgriGreen (AgG) extruded malted pearl millet (EMPM) and extruded raw pearl millet-malted pearl millet mix (ERPMMPM). Combination processing also led to a decrease in the ash, total fat, TDF, Fe and Zn content (1.76, 3.48, 14.26 g/100 g, 7.78 and 4.74 mg/100 g, respectively) of Babala (Ba) EMPM and Ba ERPMMPM (1.88, 4.22, 21.71 g/100 g, 7.24 and 4.14 mg/100 g, respectively). Beverages of 10% total solids were prepared from the samples and offered to an untrained consumer panel. The beverages were rated on appearance, colour, aroma, flavour, texture and overall acceptability on a nine-point hedonic scale. In general, Ba raw pearl millet was rated 4 (like slightly), AgG malted pearl millet was rated 6 (dislike slightly), and all other pearl millet samples from both varieties were rated 5 (neither like nor dislike)., Conclusion: Although combination processing led to an increase in carbohydrates, Ca, energy, Fe content, and 12 of the 15 amino acids measured as well as protein and starch digestibility and no change in the other nutrients measured, this did not significantly impact on the acceptability of the beverages.

A series of trisubstituted indolizine analogues has been designed as a result of a fragment-based approach to target the inhibition of mycobacterial enoyl-acyl carrier protein reductase. Anti-tuberculosis (TB) screening of the characterized compounds by a resazurin microplate assay method revealed that ethyl group at second position of indolizine nucleus exhibited activity against susceptible and multidrug-resistant strains of Mycobacterium tuberculosis at concentration of 5.5 and 11.3 μg/mL, respectively. A molecular docking study was also conducted to evaluate the stability of the active compounds, and compound with ethyl substitution at second position of indolizine nucleus showed the highest free binding energy of ΔG -24.11 (kcal/mol), a low clash score of 3.04, and high lipo score of -13.33. Indolizine analog with ethyl substitution at second position demonstrated Molecular Mechanics/Generalized Born Surface Area (-23.85 kcal/mol). Two molecular dynamics studies were computed (100 ps and 50 ns) to calculate the relationship between the potential and kinetic energies of the active anti-TB compound with time and temperature. The discovery of this lead may have a positive impact on anti-TB drug discovery.

The new-fangled bis(4-substituted benzyl) 4-(4-substitued phenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate derivatives were synthesized by the union of substituted aryl aldehyde, tert-butyl acetoacetate, ammonium carbonate with 4-substituted benzyl alcohol via Hantzsch ester synthesis in aqueous medium under catalyst-free conditions. The newly synthesized compounds were characterized by spectroscopic techniques such as IR, NMR ( 1 H and 13 C), ESI mass, elemental analysis, and single-crystal X-ray diffraction. The characterized title compounds were evaluated for the larvicidal activity against Anopheles arabiensis by standard WHO larvicidal assay method using Temephos as standard at 4 μg/ml. The title compounds bis(4-methoxybenzyl) 2,6-dimethyl-4-(4-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate and bis(4-chlorobenzyl) 2,6-dimethyl-4-(4-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate exhibited promising larvicidal activity at 65.6% and 72.2%, respectively, when compared with the standard compound at 98.9%., (© 2017 John Wiley & Sons A/S.)

Buddleja saligna (family Buddlejaceae) is a medicinal plant endemic to South Africa. Two isomeric pentacyclic triterpenes, oleanolic acid and ursolic acid, were isolated from the leaves of B. saligna using silica gel column chromatography. Compounds oleanolic acid and ursolic acid were subjected to derivatization with acetic anhydride in the presence of pyridine to obtain oleanolic acid-3-acetate and ursolic acid-3-acetate, respectively. The structures of these compounds were fully characterized by detailed nuclear magnetic resonance (NMR) investigations, which included 1 H and 13 C NMR. Molecular docking studies predicted the free binding energy of the four triterpenes inside the steroid binding pocket of Mycobacterium tuberculosis fadA5 thiolase compared to a reported inhibitor. Thus, their ability to inhibit the growth of M. tuberculosis was predicted and was confirmed to possess significant antimycobacterial activity when tested against Mycobacterium smegmatis, M. tuberculosis H 37 Rv (ATCC 25177), clinical isolates of multi-drug-resistant M. tuberculosis (MDR-TB) and extensively drug-resistant M. tuberculosis (XDR-TB) using the Micro Alamar Blue Assay. Ursolic acid was isolated from this plant for the first time.

Two recently synthesized dihydropyrimidines (DHPMs) analogues have demonstrated larvicide and repellent activity against Anopheles arabiensis. DHPMs high lipophilicity suggests that these compounds may interact directly with the membrane and modify their biophysical properties. The purpose of the present study was to characterize the interaction of both compounds with artificial membranes. Changes on the properties of DPPC films were studied using Langmuir monolayers. The presence of DHPMs in the subphase modified the interfacial characteristics of DPPC compression isotherms, causing the expansion of the monolayer, inducing the disappearance of DPPC phase transition and increasing the molecular packing of the film. Moreover, both compounds showed ability to penetrate into the lipid monolayers at molecular pressures comparable to those in biological membranes. The effects of both DHPMs on the molecular organization of DPPC liposomes were measured by fluorescence anisotropy. The results indicate that their presence between lipid molecules would induce an increasing intermolecular interaction, diminishing the bilayer fluidity mainly at the polar region. Finally, we performed free diffusion MD simulations and obtained spatially resolved free energy profiles of DHPMs partition into a DPPC bilayer through Potential of Mean Force (PMF) calculations. In agreement with the experimental assays, PMF profiles and MD simulations showed that DHPMs are able to partition into DPPC bilayers, penetrating into the membrane and stablishing hydrogen bonds with the carbonyl moiety. Our results suggest that DHPMs bioactivity could involve their interaction with the lipid molecules that modulate the supramolecular organization of the biological membranes and consequently the membrane proteins functionality., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: Coumarins are naturally occurring plant metabolites and several synthetic coumarin analogues are known for their various pharmacological properties such as anticoagulant, antimicrobial, anticancer, antioxidant, anti-inflammatory and antiviral properties. Objective; Keeping this promising pharmacological properties in mind, in the present investigation, mono/dihalogenated coumarin analogues CMRN1-CMRN7 have been synthesized and evaluated for their anticancer activity., Method: The cytotoxicity potential of the test compounds was evaluated against UACC-62, MCF-7 and PBM (Peripheral Blood Mononuclear) cell lines using MTT assay. The apoptotic potential of the coumarin compounds was evaluated against UACC-62 cell by assessing membrane change, mitochondria membrane potential, pro-apoptotic changes were investigated using the AnnexinV-PI staining, JC-1, caspase-3 enzyme kits respectively on flow cytometer., Results: The test compounds CMRN1, CMRN2, CMRN4 and CMRN5 have strongly suppressed the cell proliferation of UACC-62 and MCF-7 cancer cell lines. Furthermore the test compounds CMRN1, CMRN2, CMRN4 and CMRN5 exerted antiproliferative effects through apoptosis induction against UACC-62., Conclusion: Compounds CMRN1, CMRN2, CMRN4 and CMRN5 can be considered as lead compounds to arrive at a promising anticancer agents.

Greener synthesis of a series of novel indolizine analogues have been achieved by the cyclization of aromatic cycloimmonium ylides with electron-deficient alkynes in the presence of water as the base and solvent at 80 °C. Yield of the title compounds was good and reactions performed were eco-friendly. The structures of these newly synthesized compounds have been confirmed by spectroscopic techniques such as FTIR, NMR, LC-MS, and elemental analysis. Characterized title compounds were evaluated for larvicidal activity against Anopheles arabiensis by standard WHO larvicidal assay using Temefos as standard at 4 μg/mL. Title compounds 2e, 2f, and 2g emerged as promising larvicidal agents., (© 2016 John Wiley & Sons A/S.)