Chromobacterium violaceum (C. violaceum) is a Gram-negative, rod-shaped facultatively anaerobic bacterium implicated with recalcitrant human infections. Here, we evaluated the anti-QS and antibiofilm activities of ethyl acetate extracts of Passiflora edulis (P. edulis) on the likely inactivation of acyl-homoserine lactone (AHL)-regulated molecules in C. violaceum both by in vitro and in silico analyses. Our investigations showed that the sub-MIC levels were 2, 1, and 0.5 mg/mL, and the concentrations showed a marked reduction in violacein pigment production by 75.8, 64.6, and 35.2%. AHL quantification showed 72.5, 52.2, and 35.9% inhibitions, inhibitions of EPS production (72.8, 36.5, and 25.9%), and reductions in biofilm formation (90.7, 69.4, and 51.8%) as compared to a control. Light microscopy and CLSM analysis revealed dramatic reduction in the treated biofilm group as compared to the control. GC-MS analysis showed 20 major peaks whose chemical structures were docked as the CviR ligand. The highest docking score was observed for hexadecanoic acid, 2-hydroxy-1-(hydroxymethyl) ethyl ester bonds in the active site of CviR with a binding energy of -8.825 kcal/mol. Together, we found that hexadecanoic acid, 2-hydroxy-1-(hydroxymethyl) ethyl ester remarkably interacted with CviR to inhibit the QS system. Hence, we concluded that hexadecanoic acid, 2-hydroxy-1-(hydroxymethyl) ethyl ester of P. edulis could likely be evaluated for treating C. violaceum infections.

Inhibition of Quorum Sensing and Biofilm Formation in Chromobacterium violaceum by Fruit Extracts of Passiflora edulis.

Based on the mechanism of action of PKC-θ, the inhibition of this enzyme is considered a potential target for the treatment of autoimmune diseases such as rheumatoid arthritis (RA), inflammatory bowel disease (IBD), and psoriasis. In the present study, 57 structurally diverse tricyclic triazinone analogues as potential PKC-θ inhibitors has been taken into consideration for QSAR analysis through Monte Carlo optimization. QSAR models are developed using the balance of correlation method in the CORAL software with two target functions (TF1 and TF2). The models constructed with IIC are found more robust and authentic. The established QSAR model with best $$ {R}_{\mathrm{calibration}}^2 $$
  = 0.9653 for split 3 is considered the topmost model. The predictabilities of the recommended QSAR model are assessed through various statistical parameters. The outlier of each model is also identified using the applicability domain (AD). The common mechanistic interpretation of the increasing and decreasing attributes has been extracted by evaluating the correlation weights of diverse structural attributes obtained in three Monte Carlo optimization runs from two splits, i.e., split 3 and 4. In the last, the result of mechanistic interpretation is validated by performing the docking studies of compounds PKC03, PKC07, PKC16, PKC25, and PKC56 in the experimental structure of protein kinase C-θ (PDB ID: 4Q9Z). The numerical value of the correlation coefficient between calculated activity and binding affinity is found 0.9597. Hence, the developed QSAR models are descriptive and predictive in nature and the results are in sound agreement with the experimental observations.

Identification of good and bad fragments of tricyclic triazinone analogues as potential PKC-θ inhibitors through SMILES–based QSAR and molecular docking

Nature has provided therapeutic substances for millennia, with many valuable medications derived from plant sources. Multitarget drugs become essential in the management of various disorders, including hepatic disorders, neurological disorders, diabetes, and carcinomas. Ferulic acid is a significant potential therapeutic agent, which is easily available at low cost, possesses a low toxicity profile, and has minimum side effects. Ferulic acid exhibits various therapeutic actions by modulation of various signal transduction pathways such as Nrf2, p38, and mTOR. The actions exhibited by ferulic acid include anti-apoptosis, antioxidant, anti-inflammatory, antidiabetic, anticarcinogenic, hepatoprotection, cardioprotection, activation of transcriptional factors, expression of genes, regulation of enzyme activity, and neuroprotection, which further help in treating various pathophysiological conditions such as cancer, skin diseases, brain disorders, diabetes, Parkinson's disease, Alzheimer's disease, hypoxia, hepatic disorders, H1N1 flu, and viral infections. The current review focuses on the significance of natural products as sources of multitarget compounds, and a primary focus has been made on ferulic acid and its mechanism, role, and protective action in various ailments. 

Natural Products as Sources of Multitarget Compounds: Advances in the Development of Ferulic Acid as Multitarget Therapeutic

Ferulic acid (FA) is one of a common ingredients in Chinese herbal medicine. FA has the interesting property of promoting growth and improving meat quality in livestock, but the mechanism is not understood. This study evaluated both safety and mechanism of efficacy in zebrafish model. At 15 μg/mL or above, FA led to pericardial oedema and delayed growth in zebrafish embryos. Dietary FA promoted growth and feed assimilation in male adult zebrafish. Genes related to myogenic development (myod1, myog and myf5) were significantly upregulated by FA and muscle fibre width in skeletal muscle was increased. At 20 µg/g, FA significantly increased number of goblet cells in zebrafish intestinal tissue, and gut microbiota composition also changed. Based on 16s rRNA gene sequences, 20 μg/g FA decreased Firmicutes and increased Bacteroides. 20 μg/g FA also stimulated the expression of PPAR-α, a gene associated with fat metabolism, and decreased the expression of PPAR-β and PPAR-γ. These gene expression changes were beneficial to fatty acid synthesis and metabolism and decreased fat deposition. Our overall results indicated that FA can be a safe growth promotor in fish particularly in skeletal muscles.

Effects of ferulic acid on muscle development and intestinal microbiota of zebrafish

Bioactive constituents from natural sources are of great interest as alternatives to synthetic compounds for the treatment of various diseases, including diabetes mellitus. In the present study, phytochemicals present in Leucaena leucocephala (Lam.) De Wit leaves were identified by gas chromatography-mass spectrometry and further examined by qualitative and quantitative methods. α-Amylase enzyme activity assays were performed and revealed that L. leucocephala (Lam.) De Wit leaf extract inhibited enzyme activity in a dose-dependent manner, with efficacy similar to that of the standard α-amylase inhibitor acarbose. To determine which phytochemicals were involved in α-amylase enzyme inhibition, in silico virtual screening of the absorption, distribution, metabolism, excretion, and toxicity properties was performed and pharmacophore dynamics were assessed. We identified hexadecenoic acid and oleic acid ((Z)-octadec-9-enoic acid) as α-amylase inhibitors. The binding stability of α-amylase to those two fatty acids was confirmed in silico by molecular docking and a molecular dynamics simulation performed for 100 ns. Together, our findings indicate that L. leucocephala (Lam.) De Wit-derived hexadecanoic acid and oleic acid are natural product-based antidiabetic compounds that can potentially be used to manage diabetes mellitus.

Phytochemical Profiling in Conjunction with In Vitro and In Silico Studies to Identify Human α-Amylase Inhibitors in Leucaena leucocephala (Lam.) De Wit for the Treatment of Diabetes Mellitus.

Peroxisome proliferator-activated receptor gamma (PPARγ), ligand-activated transcription factor, is a key modulator of genes considered in diabetes development as well as treatment. Adipogenesis di...

Manokaran Sakthivel

Papers

Structure-based drug design of peroxisome proliferator-activated receptor gamma inhibitors: ferulic acid and derivatives.