Synthesis, Spectroscopic, In-vitro and Computational Analysis of Hydrazones as Potential Antituberculosis Agents: (Part-I)

Non-traditional oils with water-soluble substrate as cell growth booster for the production of mannosylerythritol lipids by Pseudozyma antarctica (ATCC 32657) with their antimicrobial activity

Among glycolipids, mannosylerythritol lipids (MEL), are mild and environmentally friendly surfactants used in various industrial applications. MELs are produced by biofermentation using non-traditional oils with various water-soluble carbon sources as cell growth booster. This substrate affects the production yield and cost of MEL. In this research work, the non-traditional oils jatropha oil, karanja oil and neem oil were used as new substrates along with glucose, glycerol and honey as new water-soluble substrates. All these oils are new feedstocks for the production of MEL using Pseudozyma antarctica (ATCC 32657). Jatropha oil, karanja oil and neem oil with honey as substrates resulted in higher MEL yields of (8.07, 7.75, and 1.86) g/L and better cell growth of (8.07, 7.75, and 1.86) g/L, respectively, than non-traditional oils with glucose and glycerol as substrates. Neem oil gave a lower yield of MEL (1.54 g/L) as well as cell growth (6.06 g/L) compared to jatropha oil and karanja oil (7.03 and 6.17) g/L, respectively. Crude MEL from the fermentation broth was detected by thin-layer chromatography (TLC), Fourier transform infrared spectrommetry (FT-IR), high performance liquid chromatography (HPLC) and proton nuclear magnetic resonance spectroscopy (1H NMR). Purified MEL has been used as an antimicrobial agent in cosmetic products associated with gram-positive and gram-negative bacteria and fungi.

Balanced QSAR and Molecular Modeling to Identify Structural Requirements of Imidazopyridine Analogues as Anti-infective Agents Against Trypanosomiases

Human African trypanosomiasis (HAT), a fatal infection caused by Trypanosoma brucei (T. brucei) is considered as a neglected disease in the tropical areas, and newer agents with unique mechanism of action are urgently needed. In this work, 65 Imidazopyridine analogues from known literature were selected for building statistically robust genetic algorithm (GA) based QSAR models. Furthermore, values for the various cross-validation properties supported its statistical robustness (model 1, [Formula: see text], RMSE[Formula: see text], MAE[Formula: see text], CCC[Formula: see text], and [Formula: see text]). Our in silico ADMET analysis revealed that a designed molecule, S10 may act as potent lead (T. brucei, pEC[Formula: see text] ([Formula: see text]M), [Formula: see text]) with better pharmacokinetics, no carcinogenicity, class III acute oral toxicity, minimal OCT1 and OCT2 inhibitions and no eye corrosion profiles. Our molecular docking analysis (on 42 drug targets) for a dataset and designed molecules demonstrated higher binding affinity of Imidazopyridine analogues with T. brucei farnesyl diphosphate synthase (TbFPPS) (PDB id: 2I19). This observation was further supported by 100[Formula: see text]ns molecular dynamics analysis retaining better stability of complex. Thus, imidazopyridine analogues would provide a promising scaffold for the development of anti-HAT agents.

Synthesis, Molecular Docking, and In vitro Antimycobacterial Studies on N'-arylidene-4-nitrobenzohydrazides

BACKGROUND

Mycobacterium tuberculosis (Mtb) is an organism that causes tuberculosis (TB). In 2019, 10 million individuals worldwide contracted tuberculosis, with 1.4 million people dying from the disease each year (World Health Organization, 2021). Hydrazones- hydrazide-based drugs have been shown to be bactericidal against M. tuberculosis replication.

OBJECTIVES

We herein intended to synthesize a series of acid hydrazones (3a-3l) by condensing 4-nitrobenzohydrazine with substituted aromatic acids in ethanol at room temperature.

MATERIALS AND METHODS

All newly synthesized compounds were characterized by standard spectroscopic techniques. Synthesized compounds were then tested for anti-mycobacterial activity against H37Rv strains. Molecular docking analysis was performed for three crystal structures of 1ENY, 1TED and 2FUM Mycobacterium tuberculosis receptors.

RESULTS

Among all tested molecules, 3i (MIC: 50 μg/mL) and 3b (MIC: 50 μg/mL) were found to be the best ligands for further development of new anti-TB drug. We found that our proposed molecules have higher docking scores, corresponding standard anti-TB agents, such as ciprofloxacin and isoniazid. Synthesized compounds were found to have druglikeness properties when tested with Lipinski's filter for drug-likeness.

CONCLUSION

Our current study proposes N'-arylidene-4-nitrobenzohydrazides as anti-TB agents. Agents with such system can be developed in future for development into active lead molecules.

Identification of Anxiolytic Potential of Niranthin: In-vivo and Computational Investigations

Anxiety is an unpleasant state, which can critically decrease the quality of life is often accompanied by nervous behaviour and rumination. Niranthin is a lignan isolated from various Phyllanthus sources. The literature survey on niranthin highlights wide ranges of the therapeutic potentials. In a present study, based on our previous investigations, we evaluated pure, isolated and characterized niranthin as an anxiolytic agent. The niranthin [6-[(2R,3R)-3-[(3,4-dimethoxyphenyl)methyl]-4-methoxy-2-(methoxymethyl)butyl]-4-methoxy-1,3-benzodioxole] was purchased from commercial source and further subjected for assessment of its anxiolytic potentials using popular animal models including Elevated plus-maze model/test (EPM) and Light & Dark Exploration test (L&D). GABA-A receptor mediation was evaluated by pretreating the mice with the GABA-A receptor antagonist Flumazenil before the EPM task. Molecular docking simulation studies (pdb id: 4COF) carried out by Vlife QSAR software showed that niranthin (docking score: - 62.1714 kcal/mol) have shown comparatively best docking score compared to the standard drug Diazepam (docking score: - 63.1568 kcal/mol). To conclude, Niranthin has probable potential in the management of anxiety disorder. Our in-silico and in-vivo analysis (indirectly) indicated the plausible role of GABA mediation for anxiolytic activity. Although, these studies are preliminary, future in depth experimental explorations will be required to use Niranthin as anti-anxiety drug in near future.

An Insight Into the Anxiolytic Effects of Lignans (Phyllanthin and Hypophyllanthin) and Tannin (Corilagin) Rich Extracts of Phyllanthus amarus : An In-Silico and In-vivo approaches

The extracts and the compounds isolated from Phyllanthus amarus Schumm and Thonn (Family: Euphorbiaceae) have shown a wide spectrum of pharmacological activities including antiviral, antibacterial, antiplasmodial, antimalarial, antimicrobial, anticancer, antidiabetic, hypolipidemic, antioxidant, hepatoprotective, nephroprotective and diurectic properties.

BACKGROUND

This investigation was aimed at exploring the anxiolytic potential of Phyllanthus amarus standardized extracts and predict probable role of marker phyto constitutents.

OBJECTIVE AND METHODS

Three standardized extracts of Phyllanthus amarus plant viz. standardized aqueous extract of Phyllanthus amarus whole plant (PAAE), standardized methanolic extract of P. amarus leaf (PAME) and the standardized hydro-methanolic extract of P. amarus leaf (PAHME) were tested in the classical animal models of anxiety: Elevated plus-maze model and Light & Dark Exploration test.

RESULTS

The lower doses of the tannin rich extract (PAHME) of the P. amarus possess significant anxiolytic activity compared to lignin rich (PAME) and aqueous extracts (PAAE), while at a higher dose (400mg/kg) the results of all three extracts appears to be potentially sedative. While the molecular docking studies support these probable anxiolytic, the sedative effects of the Phyllanthus amarus extracts could be due to the interaction of tannins and lignans with the GABAbenzodiazepine receptor complex.

CONCLUSION

The results of the present study indicate that the tannin-rich extract of the P. amarus may have potential clinical applications in the management of anxiety. It can be further studied for optimum dosage to be used as a future of anti-anxiety drug development or as a standardized Phytomedicine.