The Antibacterial Efficacy of a Compound Extracted from Marine Sediment Bacterium Enterococcus Lactis (S-2): A Comparative Analysis Through In-Vitro and In-Silico Assessments.

BACKGROUND: Marine sediment bacteria have been generating considerable attention lately due to their potential as valuable reservoirs of novel antimicrobial agents. AIM: In vitro and in silico antibacterial activities of antibacterial compounds isolated from the marine sediment bacterium Enterococcus Lactis (S-2). METHODS: Coastal sediment samples were collected from Rameswaram, Ramnathapuram District, Tamil Nadu, India. Bacteria were isolated using the crowded plate method, and their phenotypic and genotypic characteristics were studied. Purified bacteria were cultured in large volumes, secondary metabolites were extracted, and novel antibacterial agents were isolated from the aqueous extract. Novel compound antibacterial activity was studied through in-silico and invitro. The mechanism activity of antibacterial activity was confirmed by a high-resolution transmission electron microscope. RESULTS: Genotypic analysis confirmed that the isolated S-2 bacteria were Enterococcus lactis, and the aqueous extract showed antibacterial activity against Staphylococcus aureus (17 mm zone of inhibition) and Proteus mirabilis (12 mm zone of inhibition). A bioactive molecule, 13- hydroxy-9-(1-hydroxyethyl)-11-methoxy-2,4dioxapentacyclo[10.7.1.0³,4.05,²¹.0¹³,¹6]icosa- 1(20),5,7,12,14(19), 16-hexane-18-one, was isolated from aqueous extracts of the S-2 bacterium. Chromatography and spectroscopic analysis confirmed the identity of the isolated compound. Novel compound potential antibacterial activity showing against S. aureus (18 mm zone of inhibition) and MIC 250 µg/mL, which was confirmed by tetrazolium staining. The antibacterial activity mechanism was confirmed by transmission electron microscopy. Molecular docking studies show good binding (-9.9 kcal/mol) of the compound with 3U2D, while molecular dynamic simulation studies confirm the conformationally stable structure of the complex between 3U2D and 13-hydroxy-9-(1-hydroxyethyl)-11-methoxy-2,4-dioxapentacyclo [10.7.1.0³,4.05,²¹.0¹³,¹6]icosa-1(20),5,7,12,14(19), 16-hexane-18-one. It has been observed from the docking study of 3U2D with standard drug ciprofloxacin that the lower affinity is compared to the test ligand, which has a docking score of 7.3 kcal/mol. Out of interacting residues of protein 3U2D residue, Thr173 and Ile86 formed conventional hydrogen bonds. CONCLUSION: Marine bacterium E. lactis produces a novel antibacterial compound (13-hydroxy- 9-(1-hydroxyethyl)-11-methoxy-2,4-dioxapentacyclo[10.7.1.0³,4.05,²¹.0¹³,¹6]icosa- 1(20),5,7,12,14(19),16-hexane-18-one), which shows antibacterial activity against clinical S. aureus, confirmed by in vitro and in silico analysis. This molecule can used as a lead molecule for antibacterial activity.

Fungal Diseases Caused by Serious Contamination of Pharmaceuticals and Medical Devices, and Rapid Fungal Detection Using Nano-Diagnostic Tools: A Critical Review.

Fungal-contaminated compounded pharmaceuticals and medical devices pose a public health problem. This review aimed to provide an organized overview of the literature on that critical issue. Firstly, it was found that compounding pharmacies can produce drugs that are contaminated with fungi, leading to outbreaks of severe fungal diseases. Secondly, inadequate sterile compounding techniques or storage conditions, or exceeding the limit of a fungal count, can result in fungal contamination. Lastly, nanotools can be used to rapidly detect fungi, thus improving fungal diagnostic procedures. To achieve this goal, we have reviewed the published data on PubMed, the CDC, and FDA Web sites, and a literature search was undertaken to identify severe fungal infections associated with compounding pharmacies outside of hospitals, limited by the dates 2003 to 2021. The "Preferred Reporting Items for Critical Reviews" were followed in searching, including, and excluding papers. Fungal outbreaks have been documented due to contaminated pharmaceuticals and medical devices. In 2013, 55 people died from fungal meningitis caused by contaminated steroid injections containing methylprednisolone acetate. Additionally, in 2021, Aspergillus penicillioides contamination was reported in ChloraPrep drugs, which was attributed to the storage conditions that were conducive to the growth of this fungus. These incidents have resulted in severe infectious diseases, such as invasive mycoses, cornea infections, Endophthalmitis, and intestinal and gastric mycosis. By implementing preventive measures and policies, it is possible to avoid these outbreaks. Creating Nano-diagnostics presents a major challenge, where promptly diagnosing fungal infections is required to determine the proper corrective and preventive measures.

Differential Pharmacokinetic Interplay of Atorvastatin on Lacosamide and Levetiracetam on Experimental Convulsions in Mice.

BACKGROUND: The beneficial effects of statins, other than their hypocholesterolemia role, have been well documented, however, their use as an adjuvant drug with other antiseizure drugs, in the treatment of epilepsy is poorly understood. OBJECTIVE: This study aimed to investigate the symbiotic effect of ATOR along with either lacosamide (LACO) or levetiracetam (LEVE) on experimentally induced epilepsy (Maximal electro-shock-MES or pentylenetetrazol- PTZ) in mice models. METHODS: Conventional elevated-maze (EPM) and rotarod methods were performed to observe the behavioral effects. RESULTS: In both the animal models, we found that co-administration of ATOR along with LACO showed a significant reduction in hind-limb extension (HLE) and clonic convulsion (CC) responses, respectively, but not in the ATOR+LEVE treated group. Intriguingly, comparable Straub tail response and myoclonic convulsion as the diazepam (DIA) group were observed only in the ATOR+LACO treated group. Moreover, a significant muscle-grip strength was observed in both groups. Also, pharmacokinetic analysis has indicated that the mean plasma concentration of ATOR peaked at 2nd hr in the presence of LACO but marginally peaked in the presence of LEVE. An Insilico study has revealed that ATOR has a higher binding affinity toward neuronal sodium channels. CONCLUSION: This study has demonstrated that the plasma concentration of ATOR was potentiated in the presence of LACO, but not in the presence of LEVE and it has provided significant protection against both the electro and chemo-convulsive models in mice. This could be due to the symbiotic pharmacokinetic interplay of ATOR with LACO, and possibly, this interplay may interfere with sodium channel conductance.

A benzimidazole scaffold as a promising inhibitor against SARS-CoV-2.

The manuscript reports the green-chemical synthesis of a new diindole-substituted benzimidazole compound, B1 through a straightforward route in coupling between indolyl-3-carboxaldehyde and o-phenylenediamine in water medium under the aerobic condition at 75 ºC. The single crystal X-ray structural analysis of B1 suggests that the disubstituted benzimidazole compound crystallizes in a monoclinic system and the indole groups exist in a perpendicular fashion with respect to benzimidazole moiety. The SARS-CoV-2 screening activity has been studied against 1 × 10e4 VeroE6 cells in a dose-dependent manner following Hoechst 33342 and nucleocapsid staining activity with respect to remdesivir. The compound exhibits 92.4% cell viability for 30 h and 35.1% inhibition against VeroE6 cells at non-cytotoxic concentration. Molecular docking studies predict high binding propensities of B1 with the main protease (Mpro) and non-structural (nsp2 and nsp7-nsp8) proteins of SARS-CoV-2 through a number of non-covalent interactions. Molecular dynamics (MD) simulation analysis for 100 ns confirms the formation of stable conformations of B1-docked proteins with significant changes of binding energy, attributing the potential inhibition properties of the synthetic benzimidazole scaffold against SARS-CoV-2. Communicated by Ramaswamy H. Sarma.

Isolation and Identification of Bioactive Compounds with Antimicrobial Activity from Marine Facultative Anaerobe, Bacillus subtilis.

INTRODUCTION: The marine ecosystem contains many microbial species that produce unique, biologically active secondary metabolites with complex chemical structures. We aimed to isolate and identify bioactive compounds with antimicrobial properties produced by a facultative anaerobic strain of Bacillus subtilis (AU-RM-1), isolated from marine sediment. METHODOLOGY: We optimized the AU-RM-1 growth conditions, analyzed its growth kinetics and its phenotypic and genotypic characteristics. Extracts of the isolate were studied for antimicrobial activity against three clinically important microorganisms and the structure of the active compound was identified by spectroscopy. RESULTS: Antimicrobial activity of the AU-RM-1 DMSO extract was evaluated by disc diffusion assay and by serial dilution. The AU-RM-1 DMSO extract showed antimicrobial activity against Candida albicans, Escherichia coli, and Klebsiella pneumoniae. The bioactive fraction of the AURM- 1 DMSO extract was separated by TLC-bioautography at Rf = 0.49. We then used scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to study the morphological changes in the bacterial cells treated with the isolated compound. It was observed that cells seemed to shrink, and the cell walls appeared to be damaged. A bioactive compound was identified, and its structure was examined by spectroscopic analysis: a LC-MS molecular ion peak (ESI) m/z (% of relative abundance) was calculated for C19H22O3: 298.38, and found to be C19H22O3 +1: 299.51 [M+1]. The chemical structure of the compound (2-(2-{8-methoxy-5aH,6H,7H,8H,9H, 9aH-naphtho[2,1-b]furan-7-yl}ethyl)furan) was determined using 1HNMR and 13CNMR, and its purity was confirmed by HPLC. Fifteen known and previously reported compounds were also identified, in addition to the novel compound; these were lipopeptides, antibiotics and chemical moieties. CONCLUSION: The facultative anaerobic marine organism Bacillus subtilis (AU-RM-1) produces a novel bioactive secondary metabolite with antimicrobial and antifungal activity.

Lectins Are the Sparkle of Hope for Combating Coronaviruses and the Global COVID-19.

Today the crisis of coronavirus disease 2019 (COVID-19) pandemic represents a threatworldwide because it is a leading cause of human morbidity and mortality. Besides, it possessesa destroying impact on countries' economies. Therefore, there is an urgent need for hardresearch work and global collaboration to find a potential therapy. In this review, structuralgenomic variations in COVID-19 and further therapeutic options of Coronaviridae family orCOVID-19 are expressed. Lectins are natural proteins, which can exist in algae, higher plants,banana, actinomycetes, fungi, and archaea, and they have antiviral properties. Griffithsin lectin,isolated from red algae, has noteworthy efficacy against lethal SARS-CoV infection, humancoronaviruses, and other animal coronaviruses. Furthermore, all mannose-specific plant lectinshave anti-coronaviruses properties except for garlic lectins. However, lectins from mushroomscan act as immunomodulators by activating T-lymphocyte or stimulating dendrites or cytokines.The lectin may hinder glucans on viral spike protein and prevent entry and the virus's release.Lectin's anti-coronavirus activities include a glimmer of hope to tackle the global COVID-19crisis and inspire more scientific work on carbohydrate-binding agents against SARS-CoV-2.

Mechanisms of Antimicrobial Resistance: Highlights on Current Advance Methods for Detection of Drug Resistance and Current Pipeline Antitubercular Agents.

BACKGROUND: Sir Alexander Fleming accidentally discovered antibiotics in 1928. Antibiotics have played a significant role in treating infectious diseases. The extensive use of antibiotics has enabled the microorganisms to develop resistance against the antibiotics given, which has become a global concern. This review aims to examine some of the mechanisms behind resistance and advanced methods for detecting drug-resistant and antibacterial drugs in the clinical pipeline. METHODS: An extensive search was carried out in different databases, viz. Scopus, Embase, Cochrane, and PubMed. The keywords used in the search were antimicrobial resistance, antibiotic resistance, antimicrobial tolerance, antibiotic tolerance, and methods to reduce antimicrobial resistance. All the studies published in the English language and studies focusing on antibiotic resistance were included in the analysis. RESULTS: The most common mechanisms involved in antimicrobial resistance are reflux pumping, antibiotic inactivation, acquired resistance, intrinsic resistance, mutation, bio-film resistance, etc. Antibacterial medicinal products for multidrug resistance (MDR) infections are active against pathogens, which are registered in the World Health Organization (WHO) priority pathogen list (PPL). CONCLUSION: Furthermore, their innovativeness was assessed by their lack of cross-resistance. Finally, novel antibacterial drugs without pre-existing inter-resistance, especially those with highresistance gram-negative bacteria and tuberculosis (TB), are understated and urgently required.

A hydrated 2,3-diaminophenazinium chloride as a promising building block against SARS-CoV-2.

Phenazine scaffolds are the versatile secondary metabolites of bacterial origin. It functions in the biological control of plant pathogens and contributes to the producing strains ecological fitness and pathogenicity. In the light of the excellent therapeutic properties of phenazine, we have synthesized a hydrated 2,3-diaminophenazinium chloride (DAPH+Cl-·3H2O) through direct catalytic oxidation of o-phenylenediamine with an iron(III) complex, [Fe(1,10-phenanthroline)2Cl2]NO3 in ethanol under aerobic condition. The crystal structure, molecular complexity and supramolecular aspects of DAPH+Cl- were confirmed and elucidated with different spectroscopic methods and single crystal X-ray structural analysis. Crystal engineering study on DAPH+Cl- exhibits a fascinating formation of (H2O)2…Cl-…(H2O) cluster and energy framework analysis of defines the role of chloride ions in the stabilization of DAPH+Cl-. The bactericidal efficiency of the compound has been testified against few clinical bacteria like Streptococcus pneumoniae, Escherichia coli, K. pneumoniae using the disc diffusion method and the results of high inhibition zone suggest its excellent antibacterial properties. The phenazinium chloride exhibits a significant percentage of cell viability and a considerable inhibition property against SARS-CoV-2 at non-cytotoxic concentration compared to remdesivir. Molecular docking studies estimate a good binding propensity of DAPH+Cl- with non-structural proteins (nsp2 and nsp7-nsp-8) and the main protease (Mpro) of SARS-CoV-2. The molecular dynamics simulation studies attribute the conformationally stable structures of the DAPH+Cl- bound Mpro and nsp2, nsp7-nsp8 complexes as evident from the considerable binding energy values, - 19.2 ± 0.3, - 25.7 ± 0.1, and - 24.5 ± 0.7 kcal/mol, respectively.

JAK1/STAT3 regulatory effect of ß-caryophyllene on MG-63 osteosarcoma cells via ROS-induced apoptotic mitochondrial pathway by DNA fragmentation.

Currently, available treatment for osteosarcoma is combinational chemotherapy of doxorubicin, cisplatin, and methotrexate before and after surgery with overall 5-year survival rate of less than 40%. The present study was aimed to assess the anticancer effects of a phytochemical named ß-caryophyllene (BCP) in treating osteosarcoma. We assessed the effect of (BCP) on oxidative stress, proliferation, apoptosis, and inflammation in human bone cancer cells MG-63. Our results showed that BCP induced reactive oxygen species (ROS) generation at 20 µM concentration in MG-63 cells. The same dose was also shown to exhibit proapoptotic and antiproliferative effects in bone cancer cells MG-63. We demonstrated that the treatment of MG-63 cells with BCP prompted mitochondrial apoptosis via upregulation of Bax and caspase-3 and downregulation of Bcl-2 as well as prompted mitochondrial membrane potential. Our results also showed stimulation of Janus kinase 1/signal transducer and activator of transcription 3 (JAK1/STAT3) signaling pathway in bone cancer MG-63 cells upon BCP treatment along with the induction of proinflammatory genes at the messenger RNA level. Overall results suggest that the treatment of MG-63 cells with BCP promotes apoptosis and inflammation via ROS and JAK1/STAT3 signaling pathway.

Fabrication of Iron Oxide/Zinc Oxide Nanocomposite Using Creeper Blepharis maderaspatensis Extract and Their Antimicrobial Activity.

Green nanotechnology has recently had a significant influence on advances in biological applications. The surface manipulation of iron oxide NPs by zinc oxide is increasing attention for biomedical research. Therefore, this work focused on the phytochemicals of creeper Blepharis maderaspantensis (BM) water extract for synthesizing iron oxide NPs and iron oxide/zinc oxide nanocomposite. The UV spectrum analysis showed a wavelength redshift from 294 to 302 nm of iron oxide/ZnO nanocomposite, and the polydispersity index revealed that the perfect preparations of iron oxide NPs were prepared by boiling 0.25 g of the plant in deionized water then the filtrate added to ferric chloride (1:1 v/v). The HRTEM results also illustrated that amorphous iron oxide NPs are spherical and irregular in shape. However, the iron oxide/ZnO nanocomposite showed a rod shape of ZnO with an average length and width of ∼19.25 ± 3.2 × 3.3 ± 0.6 nm surrounding amorphous iron oxide NPs. Furthermore, a high antimicrobial activity with MRSA and E. coli was demonstrated by iron oxide NPs. However, because of instability and negative surface charge of the iron oxide nanocomposite, there was no antimicrobial activity. Future cytotoxic studies of the iron oxide NPs synthesized with polyphenols of BM extract are desirable, and their applications in medical purposes will be recommended.

Antifungal and antiovarian cancer properties of α Fe2O3 and α Fe2O3/ZnO nanostructures synthesised by Spirulina platensis.

Candida albicans (C. albicans) infection shows a growing burden on human health, and it has become challenging to search for treatment. Therefore, this work focused on the antifungal activity, and cytotoxic effect of biosynthesised nanostructures on human ovarian tetracarcinoma cells PA1 and their corresponding mechanism of cell death. Herein, the authors fabricated advanced biosynthesis of uncoated α-Fe2O3 and coated α-Fe2O3 nanostructures by using the carbohydrate of Spirulina platensis. The physicochemical features of nanostructures were characterised by UV-visible, high resolution transmission electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. The antifungal activity of these nanostructures against C. albicans was studied by the broth dilution method, and examined by 2', 7'-dichlorofluorescein diacetate staining. However, their cytotoxic effects against PA1 cell lines were evaluated by MTT and comet assays. Results indicated characteristic rod-shaped nanostructures, and increasing the average size of α-Fe2O3@ZnO nanocomposite (105.2 nm × 29.1 nm) to five times as compared to α-Fe2O3 nanoparticles (20.73nm × 5.25 nm). The surface coating of α-Fe2O3 by ZnO has increased its antifungal efficiency against C. albicans. Moreover, the MTT results revealed that α-Fe2O3@ZnO nanocomposite reduces PA1 cell proliferation due to DNA fragmentation (IC50 18.5 µg/ml). Continual advances of green nanotechnology and promising findings of this study are in favour of using the construction of rod-shaped nanostructures for therapeutic applications.