In vitro antimycobacterial and cytotoxic data on medicinal plants used to treat tuberculosis

Eco-Friendly Synthesis of MnO2 Nanorods Using Gmelina arborea Fruit Extract and Its Anticancer Potency Against MCF-7 Breast Cancer Cell Line

Introduction

Cancer disease is known due to its unregulated proliferation of cells that have evolved from the body’s regular cells. The disease develops as a result of epigenetic and genetic modifications, tumor suppressor gene inactivation, and oncogene activation. The present work describes an environmentally benign approach for the synthesis of manganese oxide nanoparticles (MnO₂ NPs) using Gmelina arborea fruit extract (GAE) in an aqueous medium.

Methods

The study evaluated the formation of MnO₂ NPs and their anticancer efficacy against MCF-7 breast cancer cell line.

Results

The formation of MnO₂ NPs was confirmed through powder X-ray diffractometer (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HR-TEM). The crystalline nature of as-prepared MnO₂ NPs was evident from XRD pattern. The morphology of the material was studied using SEM analysis, which suggested a rod-like nature with an average diameter of 50 nm. Further, the TEM and HR-TEM images confirmed the rod shape of the as-prepared MnO2 NPs with an interplanar distance of 0.271 nm. In addition, the concentric rings from selected area electron diffraction (SAED) analysis show the crystalline nature of the as-prepared material, which further supports the obtained XRD pattern. The anticancer efficacy of MnO₂ NPs was evaluated against MCF-7 breast cancer cell line, which showed up to 96% inhibition of the cells at 400 µg/mL concentration.

Conclusion

Bio-conjugation of MnO₂ NPs can provide enough scope for the therapeutic use of Gmelina arborea, assuming appropriate mechanistic evaluations are conducted.

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.

Analysis of Cytotoxicity of Selected Asteraceae Plant Extracts in Real Time, Their Antioxidant Properties and Polyphenolic Profile

Plants from Asteraceae family are widely used for their therapeutic effects in the treatment of gastrointestinal diseases, but the consequences of excessive intake still need to be studied. The aims of this study were the evaluation of cytotoxicity, measurement of antioxidant properties and determination of polyphenolic profile of Tanacetum vulgare L. (tansy), Achillea millefolium L. (yarrow) and Solidago gigantea Ait. (goldenrod) ethanolic extracts. The cytotoxicity of extracts was monitored by xCELLigence system in real time by using porcine intestinal epithelial cell line (IPEC-1) and by measurement of changes in metabolic activity ((3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) (MTS) assay). The antioxidant properties were measured by spectrophotometric methods and polyphenolic profiles were determined by HPLC-DAD for 50% ethanol extracts (10% w/v). Strong cytotoxic effect was recorded for tansy and yarrow extracts (125-1000 µg/mL) by xCELLigence system and MTS assay. Conversely, a supportive effect on cell proliferation was recorded for goldenrod extracts (125 µg/mL) by the same methods (p < 0.001). The antioxidant activity was in good correlation with total polyphenolic content, and the highest value was recorded for goldenrod leaves, followed by tansy leaves, goldenrod flowers and yarrow leaf extracts. The goldenrod extracts were abundant with flavonoids, whereas phenolic acid derivatives predominated in the polyphenolic profile of tansy and yarrow.

Medicinal Plants Used in the Treatment of Mental and Neurological Disorders in Ghana

Ethnopharmacological Relevance

Mental and neurological disorders are a serious public health challenge globally, particularly in developing countries where cultural factors and limited access to standard healthcare have led to a reliance on traditional medicines. However, ethnopharmacological characterization of traditional medicines used to treat these diseases is lacking. In this study, an ethnobotanical description of plant species used in treating mental and neurological disorders in Ghana and an update of their experimentally validated pharmacological relevance are provided.

Materials and Methods

Two hundred herbalists agreed to participate but sixty-six specialized in treating mental and neurological disorders were interviewed on their traditional medical practice. Literature review was conducted to verify the experimentally validated pharmacological importance of the reported plants.

Results

Thirty-two plant species belonging to twenty-eight families were identified. Most plant species had either analgesic (50%), anxiolytic (18.8%), or anticonvulsant (15.6%) properties. Others had reported sedative, anti-Alzheimer's disease, motor coordination, antipsychotic, antidepressant, cognitive enhancement, and neuroprotective properties. While Ageratum conyzoides L. (Asteraceae) and Ocimum gratissimum L. (Lamiaceae) were the most commonly mentioned species with analgesic properties, Lantana camara L. (Verbenaceae) was the most-reported anxiolytic product, with Cymbopogon citratus DC. (Gramineae), Mangifera indica L., Tetrapleura tetraptera Schum Taub. (Fabaceae), and Persea Americana Mill (Lauraceae) being the most studied anticonvulsants.

Conclusions

This study provides the first report specifically on medicinal plants used in treating mental and neurological disorders in Ghana. Most of the identified plants have been scientifically confirmed to possess neuro- and psychopharmacological properties and may serve as templates for drug development.

In vitro antimycobacterial activity and toxicity of eight medicinal plants against pathogenic and nonpathogenic mycobacterial strains

Tuberculosis (TB) caused by Mycobacterium tuberculosis remains a serious public health challenge towards which new hits are urgently needed. Medicinal plants remains a major source of new ligands against global infectious illnesses. In our laboratories, we are currently investigating locally used ethnobotanicals for novel compounds against zoonotic tuberculosis. The microplate alamar blue assay (MABA) was used to study the anti-TB activity while the CellTiter 96® AQ_ueous Assay, which is composed of solutions of a novel tetrazolium compound [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt; MTS] and an electron coupling reagent (phenazine methosulfate) PMS, was used for cytotoxic studies. Correlation coefficients (R²) were used to compare the relationship between antimycobacterial activity of the eight crude extracts against nonpathogenic strains and the pathogenic Mycobacterium bovis. Minimum inhibitory concentration (MICs) values indicated that all the eight tested medicinal plant species had activity against all the three tested mycobacterial strains. Minimum inhibitory concentration value as low as 19.5µg/mL was observed against non-pathogenic strains M. bovis. Activity of the crude extracts against M. aurum was the best predictor of natural product activity against the pathogenic Mycobacterium bovis strain, with a correlation coefficient value (R²) of 0.1371. Results obtained from the current study validate, in part, the traditional utilization of the tested medicinal plants against tuberculosis. The unripe fruits from Solanum torvum are a potential source of safe and efficacious anti-TB crude drugs as well as a source for natural compounds that act as new anti-infection agents, and thus deserve further investigation towards development of a new class of molecules with activity against sensitive and drug resistant strains of M. bovis.