Assessing the antimycobacterial activity of the bioactive fractions of the Indian medicinal plant – Justicia adhatoda L.

Justicia adhatoda L. is an Indian medicinal plant traditionally used to treat respiratory ailments in Ayurvedic and Unani medicines.  It is widespread in the Indian subcontinent. The plant leaves are known to have broad range of pharmacological activities including analgesic, anti-inflammatory, antispasmodic and antibacterial properties. Some studies have highlighted the antimicrobial effects of its major bioactive components like vasicine and vasicinone However, not much work has been done to explore the enormous benefits that the bioactive components might hold. Hence, in the present study, we explored the plant for its potential as an effective anti- mycobacterial agent. We aim to investigate the antimycobacterial effect of J. adhatoda L. plant leaf extracts on Mycobacterium smegmatis and Mycobacterium bovis (BCG) and identify, and isolate th bioactive component(s) for the plant leaf extract. The isolated components were also analyzed further for their antimycobacterial activity in synergy with Isoniazid. The leaves of J. adhatoda L. were powdered and extracted with ethanol, water, ethyl acetate, and hexane and antimycobacterial activity was assessed by MABA. The ethanol extract showed >96% and 98% reduction in colony-forming units (CFU) at 100µg/ml on Mycobacterium smegmatis and Mycobacterium bovis (BCG) respectively. Active phytoconstituent from ethanol extract was isolated and further fractionated via Prep-TLC. They were bioassayed against M. smegmatis and M. bovis (BCG) to study cytotoxicity, synergy, and external damage on the bacteria. Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) were carried out on treated bacilli to observe the external and internal cellular damage. The isolated fractions showed strong anti-mycobacterial activity, with low cytotoxicity and synergism when used with isoniazid. When subjected to electron microscopy, the fractions were found to adversely affect the cell wall and membrane of BCG, causing cytoplasmic leakage. Our study demonstrated that the active fractions isolated from J. adhatoda L. could be evaluated further for potentially effective anti-mycobacterial agents.

Chemical Biology Letters

Full text link: https://pubs.thesciencein.org/journal/index.php/cbl/article/view/247

Phytochemical and in vitro analysis of Bornetella oligospora extract as alpha-Glucosidase inhibitor

One of the first-line therapy of diabetes mellitus is alpha-glucosidase inhibitors. Due to side effects caused by synthetic drugs and limited sources, various studies have been conducted on herbal plants and macroalgae consisting of bioactive compounds with alpha-glucosidase inhibitory activity. This study examines the alpha-glucosidase inhibitory activity and phytochemical compounds in ethyl acetate and ethanol extract of Bornetella oligospora, an abundant green alga in eastern Indonesia. The result showed that ethanol and ethyl acetate extract of Bornetella oligospora contained phytochemical components such as flavonoid, glycoside, triterpenoid, and steroid. The thin layer chromatography test showed ethanol extract have five spots with Rf 0.545, 0.527, 0.5, 0.473, and 0.154, while the ethyl acetate extract has two spots with Rf 0.58 and 0.64. The alpha-glucosidase inhibition assay showed IC50 values of the ethanol extract was 11.702 ug/mL and ethyl acetate extract was 95.384 ug/mL. In conclusion, Bornetella oligospora extract has the potential as an antidiabetic agent.

Published in Chemical Biology Letters

Siswanto, M. A., Paramita, R. I., Fadilah, F., & Poerwaningsih, E. H. (2021). Phytochemical and in vitro analysis of Bornetella oligospora extract as alpha-Glucosidase inhibitor. Chemical Biology Letters, 8(1), 40–44. https://pubs.thesciencein.org/journal/index.php/cbl/article/view/120

Beneficial impacts of Astaxanthin on Biomarkers of Antioxidant status and oxidative damage in Rats exposed to Ambient air

Effect of astaxanthin from Haematococcus pluvialis on lipid peroxidation and oxidative stress induced by ambient air exposure was studied. Wistar albino rats were exposed to ambient air was administered with astaxanthin in doses varying between 0.5 to 2% of food intake. Various biological parameters like ALT, AST, ALP, malondialdehyde, hydrogen peroxide, superoxide dismutase, catalase and glutathione reductase, were estimated biochemically and the expression of Nrf2 and glutathione peroxidase genes were estimated by reverse transcriptase PCR. Plasma ALT, AST, ALP, MDA and the activity of antioxidant enzymes; SOD, GRd, catalase were found increased significantly in ambient air exposed rats. Ambient air exposure decreased the levels of glutathione, non protein thiols and GPx expression whereas total thiols and expression of Nrf2 increased. However the concurrent administration of astaxanthin was found to reverse these changes in a dose dependent manner. The results of this study revealed the ability of astaxanthin to alleviate liver toxicity and oxidative stress induced by ambient air exposure and points to the possibility of developing astaxanthin as a dietary supplement that reduce the ill effect of toxic chemicals from ambient air.

Published in: Chemical Biology Letters

Johnson, J. P., Renganthan, S., Menon, A., & Pillai, R. G. (2021). Beneficial impacts of Astaxanthin on Biomarkers of Antioxidant status and oxidative damage in Rats exposed to Ambient air. Chemical Biology Letters, 8(1), 1–9. https://pubs.thesciencein.org/journal/index.php/cbl/article/view/158

Treatment of Type 2 diabetes mellitus (T2DM): Can GLP-1 Receptor Agonists fill in the gaps?

Type 2 diabetes mellitus (T2DM) is a chronic metabolic syndrome, which occurs due to increased glucose levels in the human body. There has been lot of work in developing novel approaches to tackle this disease. GLP-1 receptor (GLP-1R), one of the class-B G-protein-coupled receptors (GPCR), is a budding molecular target to design drugs for treating type 2 diabetes. In this review, authors have summarized the physiological actions of Glucagon-like peptide-1 receptor (GLP-1R) and current available drugs based on GLP-1 RAs. Some of the exemplary studies in this area have been examined in detail. Authors conclude that development of degradation-resistant, long-acting GLP-1 receptor agonists is a promising area of research and lot of work needs to be done to understand its mechanism of action.

Published in: Chemical Biology Letters

Link: https://pubs.thesciencein.org/journal/index.php/cbl/article/view/132

1,3,4 Oxadiazole: An emerging scaffold to target different growth factors and kinases

Five member heterocyclic 1,3,4-oxadiazole derivatives were synthesized and evaluated for their anticancer activity. Compounds containing 1,3,4-oxadiazole ring in their structure are characterised by multidirectional biological activity. The important mechanism behind tumor suppression by 1,3,4-Oxadiazole is related with the inhibition of different growth factors, enzymes and kinases etc. The 1,3,4-Oxadiazole scaffold is a five member heterocyclic ring having versatile activities and created interest for synthetic organic and medicinal chemists for the designing of novel compounds having anti- cancer activity. There are great potential in the development of the simple and small 1,3,4-oxadiazole nucleus which is present in various compounds that possess considerable pharmcological properties such as anticancer and aimed to evaluate new products. The main aim of this review article is to highlight the targeted activity of 1,3,4-Oxadiazole derivatives and their structure activity relationship to generate potential anticancer agents.

Published in: Chemical Biology Letters

Link: https://pubs.thesciencein.org/journal/index.php/cbl/article/view/163

Green synthesized Allium cepa nanoparticles with enhanced antiprotozoal activities for E. gingivalis

Allium cepa has phytochemical characteristics well known to be used in our gastronomy. Due to its particle size, low systemic bioavailability is the major disadvantage associated that pose major hurdle for its use for medicinal purpose. These limitations can be overcome by converting the bulk size particles to nanosized particles. The present study was to prepare the nano-particles of Allium cepa with improved aqueous solubility, and to investigate their in-vitro efficacy against Entamoeba gingivalis, a protozoan associated with poor oral hygiene leading to advanced periodontal disease. Allium cepa nanoparticles of the size ranging 85–95 nm with the aqueous solubility of upto 3 mg/mL were prepared, and the anti-amoebic activities were tested in-vitro against Entamoeba gingivalis (ATCC 30927). The trophozoites of Entamoeba gingivalis were cultured in the presence of Allium cepa’s Bulk/nano- particles or metronidazole, the inhibition caused by each particles type at various concentrations was calculated by counting the viable trophozoites under the inverted microscope. Allium cepa nanoparticles showed inhibitory results of more than 80%, which is comparable with that of standard drug Metronidazole against E. gingivalis demonstrating its use as a potential anti-parasitic herbal drug.

Published in: Chemical Biology Letters

Link: https://pubs.thesciencein.org/journal/index.php/cbl/article/view/246

Phytochemical screening, GC-MS analysis and In-vitro Antioxidant potential of Parthenium hysterophorus Stem sequentially extracted fractions

Oxidative stress (OS) is involved in pathophysiological events of different diseases. Antioxidants mitigate and suppress the adverse effect of OS in the body. Due to lesser side effects and cost effectiveness natural antioxidant is a choice of people nowadays. The present study was designed to characterize/analyze phytochemicals and antioxidant potential in Parthenium hysterophorus (Asteraceae) stem (PHS) sequentially extracted fractions. Chemical characterization of PHS samples was carried out using Gas Chromatography-Mass Spectrometry (GC-MS) and Spectrophotometric techniques. Comparative antioxidant potential in PHS fractions was studied using in vitro antioxidant models. Thin layer chromatography (TLC) was performed to show a differential occurrence of phytochemicals in test fractions and related radical scavenging potential. PHS fractions showed differential presence of compounds. Appreciable radical scavenging, reducing power, and metal ion chelation potential was found in PHS fractions. In conclusion, P. hysterophorus stem may be considered a good source of natural antioxidant compounds.

https://pubs.thesciencein.org/journal/index.php/cbl/article/view/162

Novel 5-Nitro Isatin derivatives as DNA Gyrase inhibitors: synthesis, anti-microbial evaluation, molecular docking, ADMET predictions and QSAR studies

Novel series of 5-nitroindoline-2-ones was synthesized starting from 5-nitroindoline-2,3-dione 2 and 2-(5-nitro-2-oxoindolin-3-ylidene)hydrazine-1 carbothioamide 3. Compounds were evaluated for their antimicrobial activities. The data showed that compounds 2 and 6b have excellent antimicrobial activities against the two tested strains of G+ve bacteria Staphylococcus aureus and Streptococcus and E. coli when compared with the standards. Furthermore, in-vitro enzyme assay and molecular docking studies were performed for the compounds 2 and 6b against E. coli DNA gyrase B. Prediction of ADMET properties and QSAR study of compounds was carried out respectively.

Published in: Chemical Biology Letters

Link: https://pubs.thesciencein.org/journal/index.php/cbl/article/view/131

Medicinal applications of Saffron plant in Neurological disorders

Saffron (Crocus sativus L.) has been widely used in traditional or phytomedicine as a treatment of neurological disorders. The saffron is showing great potential to treat various neurological diseases without any apparent side effects. As there are very limited drugs available for the treatment of neurological diseases, saffron provides hope to treat the brain disorders and conditions such as anxiety, depression, Alzheimer’s disease, and Parkinson’s disease. This brief review deals with medicinal applications of saffron plant towards neurological diseases

Design, synthesis, ADME prediction and anti-hyperglycemic evaluation of new alkoxyimino-substituted phenyl carboxylic acids as potent alpha-glucosidase inhibitors

In an attempt to further explore the role of substituted carboxylic acid derivatives as antidiabetic agent, a series of alkoxyimino-substituted carboxylic acid derivatives (101-206) were designed, synthesized and evaluated for their inhibitory potential against a-amylase and a-glucosidase enzyme. Among all the tested compounds, 102 & 105 has displayed the most potent activity against a-glucosidase with the IC50 of 142.21±1.8 mM and 182.83±2.43 mM respectively, as compared to the standard drug acarbose (136.89±1.67 mM). Based on the inhibition percentage, the inhibition activity of 102 and 105 on a-glucosidase had higher potential than a-amylase. The mode of binding interactions between the a-glucosidase enzyme and the compound 102 was established to be uncompetitive using kinetic analysis. The predicted drug-likeness properties (Lipinski parameters and in silico ADME properties) of the compounds revealed their suitability as potential drug candidate.

Published in: Chemical Biology Letters

Link: https://pubs.thesciencein.org/journal/index.php/cbl/article/view/130