2020 Vol. 10, No. 4

Display Method:
JPA Prize in 2020
2020, 10(4)
Abstract(62) PDF(2)
Plant-derived secondary metabolites as the main source of efflux pump inhibitors and methods for identification
Armel Jackson Seukep, Victor Kuete, Lutfun Nahar, Satyajit D.Sarker, Mingquan Guo
2020, 10(4): 277-290.
Abstract(127) PDF(21)
The upsurge of multiple drug resistance (MDR) bacteria substantially diminishes the effectiveness of antibiotic arsenal and therefore intensifies the rate of therapeutic failure. The major factor in MDR is efflux pump-mediated resistance. A unique pump can make bacteria withstand a wide range of struc-turally diverse compounds. Therefore, their inhibition is a promising route to eliminate resistance phenomenon in bacteria. Phytochemicals are excellent alternatives as resistance-modifying agents. They can directly kill bacteria or interact with the crucial events of pathogenicity, thereby decreasing the ability of bacteria to develop resistance. Numerous botanicals display noteworthy efflux pumps inhibi-tory activities. Edible plants are of growing interest. Likewise, some plant families would be excellent sources of efflux pump inhibitors (EPIs) including Apocynaceae, Berberidaceae, Convolvulaceae, Cucur-bitaceae, Fabaceae, Lamiaceae, and Zingiberaceae. Easily applicable methods for screening plant-derived EPIs include checkerboard synergy test, berberine uptake assay and ethidium bromide test. In silico high-throughput virtual detection can be evaluated as a criterion of excluding compounds with efflux substrate-like characteristics, thereby improving the selection process and extending the identification of EPIs. To ascertain the efflux activity inhibition, real-time PCR and quantitative mass spectrometry can be applied. This review emphasizes on efflux pumps and their roles in transmitting bacterial resistance and an update plant-derived EPIs and strategies for identification.
<p>Polysaccharide-based chromatographic adsorbents for virus purification and viral clearance</p>
Guy-Alain Junter, Laurent Lebrun
2020, 10(4): 291-312.
Abstract(198) PDF(3)
<p>Viruses still pose a significant threat to human and animal health worldwide. In the fight against viral infections, high-purity viral stocks are needed for manufacture of safer vaccines. It is also a priority to ensure the viral safety of biopharmaceuticals such as blood products. Chromatography techniques are widely implemented at both academic and industrial levels in the purification of viral particles, whole viruses and virus-like particles to remove viral contaminants from biopharmaceutical products. This paper focuses on polysaccharide adsorbents, particulate resins and membrane adsorbers, used in virus purification/removal chromatography processes. Different chromatographic modes are surveyed, with particular attention to ion exchange and affinity/pseudo-affinity adsorbents among which commercially available agarose-based resins (Sepharose?) and cellulose-based membrane adsorbers (Sartobind?) occupy a dominant position. Mainly built on the development of new ligands coupled to conventional agarose/cellulose matrices, the development perspectives of polysaccharide-based chromatography media in this antiviral area are stressed in the conclusive part.</p>
Structural basis of SARS-CoV-23CLpro and anti-COVID-19 drug discovery from medicinal plants
Muhammad Tahir ul Qamar, Safar M.Alqahtani, Mubarak A.Alamri, Ling-Ling Chen
2020, 10(4): 313-319.
Abstract(566) PDF(25)
The recent pandemic of coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 has raised global health concerns. The viral 3-chymotrypsin-like cysteine protease (3CLpro) enzyme controls coronavirus replication and is essential for its life cycle. 3CLpro is a proven drug discovery target in the case of severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV). Recent studies revealed that the genome sequence of SARS-CoV-2 is very similar to that of SARS-CoV. Therefore, herein, we analysed the 3CLpro sequence, constructed its 3D homology model, and screened it against a medicinal plant library containing 32,297 potential anti-viral phytochemicals/traditional Chinese medicinal compounds. Our analyses revealed that the top nine hits might serve as potential anti- SARS-CoV-2 lead molecules for further optimisation and drug development process to combat COVID-19.
Structural elucidation of SARS-CoV-2 vital proteins: Computational methods reveal potential drug candidates against main protease, Nsp12 polymerase and Nsp13 helicase
Muhammad Usman Mirza, Matheus Froeyen
2020, 10(4): 320-328.
Abstract(322) PDF(10)
Recently emerged SARS-CoV-2 caused a major outbreak of coronavirus disease 2019 (COVID-19) and instigated a widespread fear, threatening global health safety. To date, no licensed antiviral drugs or vaccines are available against COVID-19 although several clinical trials are under way to test possible therapies. During this urgent situation, computational drug discovery methods provide an alternative to tiresome high-throughput screening, particularly in the hit-to-lead-optimization stage. Identification of small molecules that specifically target viral replication apparatus has indicated the highest potential towards antiviral drug discovery. In this work, we present potential compounds that specifically target SARS-CoV-2 vital proteins, including the main protease, Nsp12 RNA polymerase and Nsp13 helicase. An integrative virtual screening and molecular dynamics simulations approach has facilitated the identifi-cation of potential binding modes and favourable molecular interaction profile of corresponding com-pounds. Moreover, the identification of structurally important binding site residues in conserved motifs located inside the active site highlights relative importance of ligand binding based on residual energy decomposition analysis. Although the current study lacks experimental validation, the structural infor-mation obtained from this computational study has paved way for the design of targeted inhibitors to combat COVID-19 outbreak.
Rapid detection of high-risk HPV16 and HPV18 based on microchip electrophoresis
Zhaoxuan Fan, Xiao Feng, Weifei Zhang, Xueji Zhang, Jin-Ming Lin
2020, 10(4): 329-333.
Abstract(93) PDF(2)
Researches on detection of human papillomavirus (HPV) high-risk samples were carried out by poly-merase chain reaction (PCR) coupled with microchip electrophoresis (MCE). Herein, we introduced a simple, rapid, automated method for detecting high-risk samples HPV16 and HPV18. In this research, general primers were initially selected to obtain sufficient detectable yield by PCR to verify feasibility of MCM method for HPV detection, then type-specific primers were further used to evaluate the specificity of MCE method. The results indicated MCE method was capable of specifically detecting high-risk HPV16 and HPV18, and also enabled simultaneous detection of multiplex samples. This MCE method described here has been successfully applied to HPV detection and displayed excellent reliability demonstrating by sequencing results. The inherent capability of MCE facilitated HPV detection conducted in a small chip with automated, high throughput, massive parallelized analysis. We envision that MCE method will definitely pave a way for clinical diagnosis, and even on-site screening of cervical cancer.
Solid and liquid state characterization of tetrahydrocurcumin using XRPD, FT-IR, DSC, TGA, LC-MS, GC-MS, and NMR and its biological activities
Mahendra Kumar Trivedi, Parthasarathi Panda, Kalyan Kumar Sethi, Mayank Gangwar, Sambhu Charan Mondal, Snehasis Jana
2020, 10(4): 334-345.
Abstract(73) PDF(5)
Tetrahydrocurcumin (THC) is one of the major metabolites of curcumin (CUR), an ancient bioactive natural polyphenolic compound. This research article describes both the solid and liquid state charac-terization of THC using advanced spectroscopic and thermo-analytical techniques. Anti-inflammatory, anti-oxidant, and neuroprotective activities of THC were investigated using in vitro cell lines. Liquid chromatography-mass spectrometry analysis revealed that our sample comprised 95.15% THC, 0.51% tetrahydrodemethoxycurcumin (THDC), 3.40% hexahydrocurcumin, and 0.94% octahydrocurcumin. Gas chromatography-mass spectrometry analysis indicated the presence of 96.68% THC and 3.32% THDC. THC in solution existed as keto-enol tautomers in three different forms at different retention time, but the enol form was found to be dominant, which was also supported by nuclear magnetic resonance analysis. THC was thermally stable up to 335.55 ℃. THC exhibited more suppression of cytokines (TNF-α, IL-1β, and MIP-1α) than CUR in a concentration-dependent manner in mouse splenocytes, while NK-cell and phagocytosis activity was increased in macrophages. THC showed a significant reduction of free radicals (LPO) along with improved antioxidant enzymes (SOD and catalase) and increased free radical scav-enging activity against ABTS+ radicals in HepG2 cells. THC displayed higher protection capability than CUR from oxidative stress and neuronal damage by improving cell viability against H2O2 induced HepG2 cells and MPP+ induced SH-SY5Y cells, respectively, in a concentration-dependent manner. Thus, a variation of the biological activities of THC might rely on its keto-enol form and the presence of other THC analogs as impurities. The present study could be advantageous for further research on THC for better understanding its physicochemical properties and biological variation.
Identification of impurities in nafamostat mesylate using HPLC-IT-TOF/MS: A series of double-charged ions
Yuxin Zhang, Lufan An, Lin Zhang, Rulin Wang, Yuan Tian, Zunjian Zhang
2020, 10(4): 346-350.
Abstract(71) PDF(4)
Nafamostat mesylate is a serine protease inhibitor used in the treatment of acute pancreatitis. The im-purities in nafamostat mesylate, the active pharmaceutical ingredient (API), were profiled via high performance liquid chromatography tandem ion trap coupled with time-of-flight mass spectrometer (HPLC-IT-TOF/MS). The chromatography was performed on an ACE-3 C18 column (200 mm × 4.6 mm, 3μm) using methanol and 0.1% formic acid in purified water as mobile phase at a flow rate of 1.0 mL/min. The ions were detected by IT-TOF/MS with a full-scan mass analysis from m/z 100 to 800. In total, eleven impurities were detected in nafamostat mesylate API. The impurity profile was estimated based on the HPLC-IT-TOF/MS data, including accurate masses, MSn fingerprints of fragmentation pathways and a series of double-charged ions. Finally, seven impurities were identified and reported for the first time. The results will provide technical support for the quality control and clinical safety of nafamostat mesylate.
TGA/Chemometrics addressing innovative preparation strategies for functionalized carbon nanotubes
Roberta Risoluti, Giuseppina Gullifa, Elena Carcassi, Andrea Masotti, Stefano Materazzi
2020, 10(4): 351-355.
Abstract(78) PDF(2)
In this work, functionalized carbon nanotubes (CNTs) using two polyamine polymers, polyethyleneimine (PEI) and polyamidoamine dendrimer (PAMAM), were investigated by thermal analysis in order to address preparation strategies to obtain low cytotoxic compounds with the ability to conjugate micro-RNAs and, at the same time, to transfect efficiently endothelial cells. Thermogravimetric analysis (TGA) was coupled to chemometrics as a novel analytical strategy to characterize functionalized CNTs from different preparation conditions. In particular, two starting materials were considered:very small CNTs and carboxylated CNTs (CNT-COOH) in order to examine the affinity with polymers. Chemometrics permitted to compare results from TGA and to investigate the effect of a number of factors affecting the synthesis of coated nanotubes including a different amount of involved polymer and the time required for the suspension for a satisfactory and reproducible preparation procedure. The results demonstrated the effectiveness of TGA as a tool able to address synthesis of coated CNTs to be employed as efficient drug delivery vectors in biomedical applications.
An integrated spectroscopic strategy to trace the geographical origins of emblic medicines:Application for the quality assessment of natural medicines
Luming Qi, Furong Zhong, Yang Chen, Shengnan Mao, Zhuyun Yan, Yuntong Ma
2020, 10(4): 356-364.
Abstract(69) PDF(2)
Emblic medicine is a popular natural source in the world due to its outstanding healthcare and therapeutic functions. Our preliminary results indicated that the quality of emblic medicines might have an apparent regional variation. A rapid and effective geographical traceability system has not been designed yet. To trace the geographical origins so that their quality can be controlled, an integrated spectroscopic strategy including spectral pretreatment, outlier diagnosis, feature selection, data fusion, and machine learning algorithm was proposed. A featured data matrix (245 × 220) was successfully generated, and a carefully adjusted RF machine learning algorithm was utilized to develop the geographical traceability model. The results demonstrate that the proposed strategy is effective and can be generalized. Sensitivity (SEN), specificity (SPE) and accuracy (ACC) of 97.65%, 99.85% and 97.63% for the calibrated set, as well as 100.00% predictive efficiency, were obtained using this spectroscopic analysis strategy. Our study has created an integrated analysis process for multiple spectral data, which can achieve a rapid, nondestructive and green quality detection for emblic medicines originating from seventeen geographical origins.
Magnetic metal organic framework for pre-concentration of ampicillin from cow milk samples
Ahmad Reza Bagheri, Mehrorang Ghaedi
2020, 10(4): 365-375.
Abstract(80) PDF(1)
The aim of this study is a present of a simple solvothermal synthesis approach to preparation of Cu-based magnetic metal organic framework (MMOF) and subsequently its application as sorbent for ultrasound assisted magnetic solid phase extraction (UAMSPE) of ampicillin (AMP) from cow milk samples prior to high performance liquid chromatography-Ultraviolet (HPLC-UV) determination. Characteristics of pre-pared MMOF were fully investigated by different techniques which showed the exclusive properties of proposed sorbent in terms of proper functionality, desirable magnetic property and also high specific surface area. Different influential factors on extraction recovery including sorbent dosage, ultrasonic time, washing solvent volume and eluent solvent volume were assessed using central composite design (CCD) based response surface methodology (RSM) as an operative and powerful optimization tool. This is the first report for determination of AMP using MMOF. The proposed method addressed some drawbacks of other methods and sorbents for determination of AMP. The presented method decreases the extraction time (4 min) and also enhances adsorption capacity (250 mg/g). Moreover, the magnetic property of presented sorbent (15 emu/g) accelerates the extraction process which does not need filtration, centrifuge and precipitation procedures. Under the optimized conditions, the proposed method is applicable for linear range of 1.0-5000.0μg/L with detection limit of 0.29μg/L, satisfactory recoveries (≥95.0%) and acceptable repeatability (RSD less than 4.0%). The present study indicates highly promising perspectives of MMOF for highly effective analysis of AMP in complicated matrices.
Electrochemical and in silico approaches for liver metabolic oxidation of antitumor-active triazoloacridinone C-1305
Agnieszka Pot(e)ga, Dorota (Z)elaszczyk, Zofia Mazerska
2020, 10(4): 376-384.
Abstract(74) PDF(1)
5-Dimethylaminopropylamino-8-hydroxytriazoloacridinone (C-1305) is a promising antitumor com-pound developed in our laboratory. A better understanding of its metabolic transformations is still needed to explain the multidirectional mechanism of pharmacological action of triazoloacridinone de-rivatives at all. Thus, the aim of the current work was to predict oxidative pathways of C-1305 that would reflect its phase Ⅰ metabolism. The multi-tool analysis of C-1305 metabolism included electrochemical conversion and in silico sites of metabolism predictions in relation to liver microsomal model. In the framework of the first approach, an electrochemical cell was coupled on-line to an electrospray ioni-zation mass spectrometer. The effluent of the electrochemical cell was also injected onto a liquid chromatography column for the separation of different products formed prior to mass spectrometry analysis. In silico studies were performed using MetaSite software. Standard microsomal incubation was employed as a reference procedure. We found that C-1305 underwent electrochemical oxidation pri-marily on the dialkylaminoalkylamino moiety. An unknown N-dealkylated and hydroxylated C-1305 products have been identified. The electrochemical system was also able to simulate oxygenation re-actions. Similar pattern of C-1305 metabolism has been predicted using in silico approach. Both proposed strategies showed high agreement in relation to the generated metabolic products of C-1305. Thus, we conclude that they can be considered as simple alternatives to enzymatic assays, affording time and cost efficiency.
Comparative pharmacokinetics of six major compounds in normal and insomnia rats after oral administration of Ziziphi Spinosae Semen aqueous extract
Chenhui Du, Yan Yan, Chenxi Shen, Xiaofang Cui, Xiangping Pei, Xuemei Qin
2020, 10(4): 385-395.
Abstract(51) PDF(6)
Ziziphi Spinosae Semen (ZSS), a traditional Chinese medicine, is used in clinics for the treatment ofinsomnia in China and other Asian countries. Herein, we described for the first time a comparative pharmacokinetics study of the six major compounds of ZSS in normal control (NC) and para-chlor-ophenylalanine (PCPA)-induced insomnia model (IM) rats that were orally administered the aqueous extract of ZSS. An ultra-high-performance liquid chromatography coupled with quadrupole orbitrap mass (UHPLC-Q-Orbitrap-MS) method was developed and validated for the simultaneous determination of coclaurine, magnoflorine, spinosin, 6'''-feruloylspinosin, jujuboside A (JuA), and jujuboside B (JuB) in ZSS in rat plasma. The established approach was successfully applied to a comparative pharmacokinetic study. The systemic exposures of spinosin and 6'''-feruloylspinosin were decreased in the IM group compared to the NC group, while plasma clearance (CL) was significantly increased. The Tmax values of JuA and JuB in IM rats were significantly lower than those in NC rats. The T1/2 of JuA in the IM group was significantly accelerated. The pharmacokinetic parameters of coclaurine and magnoflorine were not evidently affected between the two groups. These results indicate that the pathological state of insomnia altered the plasma pharmacokinetics of spinosin, 6'''-feruloylspinosin, JuA, and JuB in the ZSS aqueous extract, providing an experimental basis for the role of ZSS in insomnia treatment. The comparative pharmacokinetics-based UHPLC-Q-Orbitrap-MS using full-scan mode can therefore provide a reliable and suitable means for the screening of potentially effective substances applied as quality markers of ZSS.