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Artemisia vulgaris seeds extrude hydrogel (AVH), which shows extraordinary swelling in water, at pH 6.8, and 7.4, which follows second-order kinetics. AVH exhibits reversible swelling/deswelling in ethanol and normal saline as well at pH 7.4 and pH 1.2. Therefore, AVH shows stimuli-responsiveness in different physiological conditions, solvents, and electrolytes. The superporous nature of AVH in swollen/freeze-dried sculpture is exposed in their SEM micrographs. AVH-based aceclofenac tablet formulations offer sustained-release under simulated conditions of the gastrointestinal tract (GIT) in terms of pH and transit time. Pharmacokinetic studies also show the delay and prolonged plasma concentration with tmax of 8 h, therefore, such formulations can be used to enhance the bioavailability of aceclofenac. The swelling behavior of the AVH tablet is also assessed using MRI. The in vivo fate of the AVH tablet is monitored by X-ray during the transit through the GIT. Acute toxicity studies of AVH indicate the absence of any toxicity which reveals the safety profile of AVH. Therefore, AVH can be used for oral, topical and ophthalmic drug delivery systems. These results establish the potential of AVH as a stimuli sensitive, pH-dependent, and sustained-release biomaterial for targeted drug delivery.

Hydrogel forming polysaccharides are attracting attention for the design of diverse nature silver nanoparticles (Ag NPs) with potential biological applications. Herein, we report the green synthesis of Ag NPs and their antimicrobial activity along with their potential application in wound dressings. Glucuronoxylan (GX) isolated from seeds of Mimosa pudica (MP) was used as a stabilizing/capping agent to prepare the NPs under diffused sunlight using different concentrations of AgNO3. The progress of the reaction was monitored using a UV-visible spectrophotometer and characteristic surface plasmon absorption (SPR) bands were found in the range of 390–465 nm. The morphology and elemental composition of the synthesized Ag NPs were analyzed using scanning electron microscopy equipped with STEM and EDS detectors and the diameter of the Ag NPs was found to be in the range of 2 to 18 nm. The synthesized NPs exhibited antimicrobial potential against Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, Aspergillus niger, Penicillium notatum, Rhizopus stolonifer and Actinomycetes odontolyticus. The minimal inhibitory concentrations (MICs) of the Ag NPs against different pathogenic strains were determined. Moreover, the dressing prepared from Ag NP impregnated GX exhibited a remarkable wound healing potential in rabbits. In situ synthesized Ag NPs were stored in the form of GX thin films and their UV/vis spectra exhibited that the texture of the Ag NPs remained intact after a six month storage period.

Oxidised 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphorylcholine (OxPAPC) induces the production of proinflammatory chemokines has been widely studied for its role in vascular inflammation. There is increasing evidence on the role of chalcones as potential anti-inflammatory agents but less is known about its effects on OxPAPC-induced chemokines production and the involvement of unfolded protein response (UPR) signalling, particularly through XBP1 pathway. The present study sought to investigate the inhibitory potential of synthetic chalcone derivatives on the release of interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1), induced by OxPAPC through XBP1 signalling pathway on differentiated U-937 macrophages. The effects of synthetic chalcone derivatives on the chemokines productions were investigated using enzyme-linked immunosorbent assays, while the inhibitions of XBP1 signalling were detected using western immunoblot. Results show that all the three tested synthetic chalcone derivatives inhibited OxPAPC-induced chemokines production in a concentration-dependent manner. Compound 1.5 exhibited the strongest inhibition of IL-8 and MCP-1 at 61.4 ± 4.23% and 63.8 ± 2.16%, respectively. Compound 1.5 also achieved the lowest IC50 values for both IL-8 (18.33 ± 1.59 μM) and MCP-1 (13.05 ± 1.37 μM) inhibitions. For XBP1 protein expression, both compound 1.4 and 1.5 exhibited significant concentration-dependent suppression of the protein expressions. The results suggest that synthetic chalcone derivatives may serve as potential alternatives for future development of anti-inflammatory agents, particularly in vascular inflammation.

Studies on the discovery of tyrosinase enzyme inhibitors and exploration for better cytotoxic agents remain an important line in drug discovery and development. A series of synthetic chalcones and pyrazoline derivatives was evaluated for their inhibitory effects on the diphenolase activity of mushroom tyrosinase. The effects of these compounds on proliferation and microtubule assembly were also evaluated in seven different cancer cell lines. The results revealed that some of the synthetic compounds showed significant inhibitory activity, with four compounds being more potent tyrosinase inhibitors than the reference standard inhibitor kojic acid. Several compounds were toxic to cancer cell lines. Compound 1a was found to possess the highest anticancer activity towards all cell lines with an IC50 in the range of 0.9–2.2 μM. Seven of the compounds showed considerable tubulin polymerization activity at a concentration of 25 μM. Molecular modeling studies of these synthetic compounds were performed to investigate their interactions with the tyrosinase enzyme. The structure–activity relationship (SAR) study using in-silico analysis matched well with the in vitro tumour cell inhibitory activity.

A hydroxypropylcellulose–succinic anhydride (HPC–SAn) conjugate was synthesized homogeneously at 80 °C for 6 h under N2 in N,N-dimethylacetamide (DMA). The HPC–SAn conjugate was further covalently linked with salicylic acid (SA) drug using the versatile reagent ZrOCl2·8H2O at 80 °C for 6 h. Multiple crosslinking of the benign HPC–SAn–SA conjugate was achieved using oxalyl chloride. The resultant cross-linked prodrug (CL-HPC–SAn–SA conjugate) was characterized using different spectroscopic techniques. UV/Vis analysis of the HPC–SAn–SA conjugate has indicated that it contains 26 mg of SA per 100 mg. CL-HPC–SAn–SA showed reasonably good swelling properties in water and at different physiological pH values (6.8 and 7.4). However, negligible swelling was observed at acidic pH (1.2). Kinetic studies revealed that CL-HPC–SAn–SA followed second order swelling kinetics. Additionally, the CL-HPC–SAn–SA conjugate showed stimuli responsive (pH 7.4/1.2) swelling–deswelling properties. The effect of different pH values (1–10) on the swelling of CL-HPC–SAn–SA was also studied. Thermal analysis revealed that the cross-linked prodrug CL-HPC–SAn–SA was thermally more stable compared to pure SA. This method of multiple crosslinking of drugs with polysaccharides and the resultant prodrugs has a high potential for pharmaceutical and medicinal applications.

Gram-negative members of the ESCAPE family are more difficult to treat, due to the presence of an additional barrier in the form of a lipopolysaccharide layer and the efficiency of efflux pumps to pump out the drugs from the cytoplasm. The development of alternative therapeutic strategies to tackle ESCAPE Gram-negative members is of extreme necessity to provide a solution to the cause of life-threatening infections. The present investigations demonstrated that compounds 17, 20, 25 and 26 possessing the presence of electron donating (OH and OCH3) groups on the phenyl rings are highly potent; whereas compounds 9, 10, 15, 16, 18, 33 and 36 showed moderate activity against Gram-negative bacteria. An excellent dose-dependent antibacterial activity was established compared to that of the standard antibiotic ampicillin. Significant anti-biofilm properties were measured quantitatively, showing optical density (O.D) values of 0.51 ± 015, 0.63 ± 0.20, 0.38 ± 0.07 and 0.62 ± 0.11 at 492 nm and the leakage of cellular components by the compounds, such as 17, 20, 25 and 26, increased the O.D. of respective treated samples compared to the control. In addition, the implication of experimental results is discussed in the light of the lack of survivability of planktonic bacteria and biofilm destruction in vitro. These results revealed the great significance of the development of a new generation of synthetic materials with greater efficacy in anti-biofilm properties by targeting to lock the bio-film associated protein Bap in Gram-negative bacteria.