Synergistic antimicrobial and antibiofilm activities of piperic acid and 4-ethylpiperic acid amides in combination with ciprofloxacin

Synthesis, characterization, and anti-inflammatory activity of tetrahydropiperine, piperic acid, and tetrahydropiperic acid via down regulation of NF-κB pathway

The present study describes the synthesis, characterization, and evaluation of tetrahydropiperine (THP), piperic acid (PA), and tetrahydropiperic acid (THPA) as anti-inflammatory agents. THPA demonstrated potent anti-inflammatory activity among all the compounds. The anti-inflammatory potential was investigated in both in-vitro and in-vivo experimental models. Our findings demonstrated that THPA effectively suppressed the production of pro-inflammatory mediators, including nitric oxide and pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β) in both in vitro and in vivo. Additionally, THPA attenuated the expression of i-NOS and COX-2 in RAW 264.7 macrophages. The oral administration of THPA significantly reduced carrageenan induced paw edema thickness and alleviated liver, lung, and kidney injury induced by LPS. THPA also reduced the infiltration of inflammatory cells, prevented the occurrence of significant lesions, and mitigated tissue damage. Moreover, THPA significantly improved the survival rate of mice challenged with LPS. Our western blot studies also found that LPS induced NF-κB activation was downregulated by treatment with THPA in an in vivo system. These results collectively illustrated the potential of THPA as a therapeutic agent for treating inflammatory diseases.

A New Method for Discovering Plant Biostimulants

Structurally well-defined compounds have advantages for quality control in plant biostimulant production and application processes. Humic acid (HA) is a biostimulant that significantly affects plant growth, and soil-dwelling Protaetia brevitarsis larva (PBLs) can rapidly convert agricultural waste into HA. In this study, we use PBLs as a model to investigate HA formation and screen for structurally well-defined HA-related plant biostimulant compounds. Dephasing magic angle spinning nuclear magnetic resonance (13C DD-MAS NMR) analysis indicated HA structural changes during PBL digestion; metabolic profiling detected seven HA-related aromatic ring-containing compounds. A total of six compounds that significantly stimulate plant growth were identified through plant experiments, and all six compounds demonstrate the ability to enhance seed germination. It is noteworthy that piperic acid exhibits a remarkable promotion of root growth in plants, a finding reported for the first time in this study. Thus, this study not only provides insights into the insect-mediated transformation of HA but also illustrates a new method for discovering structurally well-defined plant biostimulant compounds.

Synthesis, conformation and cytotoxic activity of short hybrid peptides containing conformationally constrained 1-(aminomethyl)cyclohexanecarboxylic acid and gabapentin

The present work describes the synthesis,conformation and cytotoxic activities of short β/γ hybrid peptides, Boc-β^2,2-Ac₆c-Gpn-NHMe, BG1; Boc-(β^2,2-Ac₆c-Gpn)₂-OMe, BG2; Boc-(β^2,2-Ac₆c-Gpn)₃-OMe, BG3; H-β^2,2-Ac₆c-Gpn-NHMe, BG4; H-(β^2,2-Ac₆c-Gpn)₂-OMe, BG5; H-(β^2,2-Ac₆c-Gpn)₃-OMe, BG6, Boc-β^2,2-Ac₆c-Gpn-OMe, BG7 and H-β^2,2-Ac₆c-Gpn-OMe, BG8. Mixed C₆/C₇ conformations were observed for β/γ hybrid peptides. Further, BG1-BG8 were screened against MCF-7 (Breast cancer), A549 (Lung Cancer), PC-3 (Prostate cancer), HCT-116 (Colon cancer), and MDA-MB-231 (Breast cancer) cell lines. Among all, BG6 exhibited potent cytotoxicity against all cancer cell lines with IC₅₀ ranging from 1.6 μM to 6.3 μM with relatively low cytotoxicity against normal epithelial breast cell line fR-2 and human embryonic kidney cell line HEK-293. Minimal hemolytic activity was observed for BG6 against human erythrocytes. Peptide BG6 displayed anti-migratory and anti-invasive potentials showing strong interactions with intrinsic apoptotic markers Bcl-2, Bax, and cleaved-PARP, as well as the induction of the mitochondria maladjustment mediated apoptosis.

An Overview of Biofilm Formation-Combating Strategies and Mechanisms of Action of Antibiofilm Agents

Biofilm formation on surfaces via microbial colonization causes infections and has become a major health issue globally. The biofilm lifestyle provides resistance to environmental stresses and antimicrobial therapies. Biofilms can cause several chronic conditions, and effective treatment has become a challenge due to increased antimicrobial resistance. Antibiotics available for treating biofilm-associated infections are generally not very effective and require high doses that may cause toxicity in the host. Therefore, it is essential to study and develop efficient anti-biofilm strategies that can significantly reduce the rate of biofilm-associated healthcare problems. In this context, some effective combating strategies with potential anti-biofilm agents, including plant extracts, peptides, enzymes, lantibiotics, chelating agents, biosurfactants, polysaccharides, organic, inorganic, and metal nanoparticles, etc., have been reviewed to overcome biofilm-associated healthcare problems. From their extensive literature survey, it can be concluded that these molecules with considerable structural alterations might be applied to the treatment of biofilm-associated infections, by evaluating their significant delivery to the target site of the host. To design effective anti-biofilm molecules, it must be assured that the minimum inhibitory concentrations of these anti-biofilm compounds can eradicate biofilm-associated infections without causing toxic effects at a significant rate.