15 research outputs found
Mechanical Alloying Integrated with Cold Spray Coating for Fabrication Cu<sub>50</sub>(Ti<sub>50−x</sub>Ni<sub>x</sub>), x; 10, 20, 30, and 40 at.% Antibiofilm Metallic Glass Coated/SUS304 Sheets
Antibacterial agents derived from conventional organic compounds have traditionally been employed as a biofilm protective coating for many years. These agents, on the other hand, often include toxic components that are potentially hazardous to humans. Multiple approaches have been investigated over the last two decades, including the use of various metallic and oxide materials, in order to produce a diverse variety of usable coating layers. When it comes to material coating approaches, the cold spray technique, which is a solid-state method that works well with nanopowders, has shown superior performance. Its capacity to produce unique material coating in ways that are not possible with other thermal methods is the primary reason for its importance in contemporary production. The present work has been addressed in part to explore the possibility of employing mechanically alloyed Cu50(Ti50−xNix)x; x = 10, 20, 30, and 40 at.% metallic glass powders, for producing an antibiofilm/SUS304 surface protective coating, using the cold spray approach. In this study, elemental Cu, Ti, and Ni powders were low-energy ball milled for 100 h to fabricate metallic glassy powders with different Ni contents. The as-prepared metallic glassy powders were utilized to coat SUS304 sheets, using the cold spraying process. With high nanohardness values, the as-fabricated coating material, in particular Cu50Ti20Ni30, demonstrated remarkable performance in comparison to other materials in its class. Furthermore, it displayed excellent wear resistance while maintaining a low coefficient of friction, with values ranging from 0.32 to 0.45 in the tested range. E. coli biofilms were formed on 20 mm2 SUS304 sheet coated coupons, which had been injected with 1.5 108 CFU mL−1 of the bacterium. With the use of nanocrystalline Cu-based powders, it is feasible to achieve considerable biofilm inhibition, which is a practical strategy for accomplishing the suppression of biofilm formation
Fluorescent Organic Nanoparticles: New Generation Materials with Diverse Analytical and Biomedical Applications
This book provides a critical review of recent advances in the development of fluorescent organic nanoparticles as materials of choice for the design and fabrication of sensors, bioimaging agents and drug delivery systems. The properties and functions of nanoparticles differ significantly from those of their parent entities or their bulk phases. Two of their most important features are their increased surface-to volume ratio, and the formation of surface structures differing from those in their bulk phases.
In addition, the book discusses the synthesis of fluorescent conjugated polymers, self-assembled fluorescent nanoparticles, polydopamine nanoparticles, and aggregation-induced-emission or aggregation-induced-emission enhancement nanomaterials. In closing, the book provides an outlook on future research and development in fluorescent organic nanoparticles as smart materials with an impressive range of potential applications
Spectroscopic and Molecular Docking Investigation on the Interaction of Cumin Components with Plasma Protein: Assessment of the Comparative Interactions of Aldehyde and Alcohol with Human Serum Albumin
The interaction of the important plasma protein, human serum albumin (HSA), with two monoterpenes found in cumin oil, i.e., cuminaldehyde (4-isopropylbenzaldehyde) and cuminol (4-isopropylbenzyl alcohol), was studied in this paper. Both experimental and computational methods were utilized to understand the mechanism of binding. The UV absorption profile of HSA changes in the presence of both cuminaldehyde and cuminol, due to the interaction between HSA with both monoterpenes. The intrinsic fluorescence intensity of HSA was also quenched on the sequential addition of both ligands, due to change in the microenvironment of the fluorophore present in the former. Quenching of HSA by cuminaldehyde was much higher in comparison to that in the presence of cuminol. Fluorescence quenching data were analyzed using modified Stern-Volmer and Lineweaver-Burk methods, which suggested that the binding mechanism was of a static type for both ligands. In both cases, the binding was favored by the domination of hydrophobic as well as hydrogen bonding/Van der Waals forces. Both ligands partially unfolded the secondary structure of HSA, although the effect of cuminaldehyde was more pronounced, as compared to cuminol. The preferred binding site of cuminaldehyde and cuminol inside HSA was also the same; namely, drug binding site 1, located in subdomain IIA. The study showed that cuminaldehyde binds strongly with albumin as compared to its alcohol counterpart, which is due to the more hydrophobic nature of the former
Chromatographic finger print analysis of anti–inflammatory active extract fractions of aerial parts of Tribulus terrestris by HPTLC technique
Objective: To develop HPTLC fingerprint profile of anti-inflammatory active extract fractions of Tribulus terrestris (family Zygophyllaceae).
Methods: The anti-inflammatory activity was tested for the methanol and its fractions (chloroform, ethyl acetate, n-butanol and aqueous) and chloroform extract of Tribulus terrestris (aerial parts) by injecting different groups of rats (6 each) with carrageenan in hind paw and measuring the edema volume before and 1, 2 and 3 h after carrageenan injection. Control group received saline i.p. The extracts treatment was injected i.p. in doses of 200 mg/kg 1 h before carrageenan administration. Indomethacin (30 mg/kg) was used as standard. HPTLC studies were carried out using CAMAG HPTLC system equipped with Linomat IV applicator, TLC scanner 3, Reprostar 3, CAMAG ADC 2 and WIN CATS-4 software for the active fractions of chloroform fraction of methanol extract.
Results: The methanol extract showed good antiedematous effect with percentage of inhibition more than 72%, indicating its ability to inhibit the inflammatory mediators. The methanol extract was re-dissolved in 100 mL of distilled water and fractionated with chloroform, ethyl acetate and n-butanol. The four fractions (chloroform, ethyl acetate, n-butanol and aqueous) were subjected to anti-inflammatory activity. Chloroform fraction showed good anti-inflammatory activity at dose of 200 mg/kg. Chloroform fraction was then subjected to normal phase silica gel column chromatography and eluted with petroleum ether-chloroform, chloroform-ethyl acetate mixtures of increasing polarity which produced 15 fractions (F1-F15). Only fractions F1, F2, F4, F5, F7, F9, F11 and F14 were found to be active, hence these were analyzed with HPTLC to develop their finger print profile. These fractions showed different spots with different Rf values.
Conclusions: The different chloroform fractions F1, F2, F4, F5, F7, F9, F11 and F14 revealed 4, 7, 7, 8, 9, 7, 7 and 6 major spots, respectively. The results obtained in this experiment strongly support and validate the traditional uses of this Sudanese medicinal plant
A New Cytotoxic Dimeric Sesquiterpene Isolated from Inula racemosa Hook. f. (Root): In Vitro and In Silico Analyses
A new dimeric sesquiterpene named disesquicin (compound 1) was isolated from Inula racemosa roots by normal-phase MPLC (Medium Pressure Liquid Chromatography), and its structure was established by using extensive spectral analysis. Compound 1, when tested on different human cancer cell lines, showed marked cytotoxic activity (IC50 (µg/mL): 5.99 (MDA-MB), 9.10 (HeLa), and 12.47 (A549)). Docking study revealed that it binds at the catalytic domain of PLK-1 and interacts with catalytic site residues Leu59, Gly60, Lys61, Gly62, Cys67, Ala80, Lys82, Leu130, Arg136, Ser137, Leu139, Glu140, Lys178, Gly180, Asn181, Phe183, and Asp194. The binding of compound 1 to PLK-1 is spontaneous in nature as evident by a free energy of—8.930 kcal mol−1, corresponding to a binding affinity of 3.54 × 106 M−1. Results showed that compound 1 exhibited cytotoxic potential that was further confirmed by in vivo investigations
Development and validation of UPLC-PDA method for concurrent analysis of bergenin and menisdaurin in aerial parts of Flueggea virosa (Roxb. ex Willd.)
Bergenin and menisdaurin are biologically active components which are found in plant Flueggea virosa (Phyllanthaceae). Bergenin has pharmacological actions such as chemopreventive and antihepatotoxic while menisdaurin has an anti-viral activity which needs its evaluation by an analytical method (UPLC-PDA method) that can be applied to the quality control of pharmaceutical preparations. The developed UPLC-PDA method was applied for identification and quantification of standards bergenin and menisdaurin in the methanol extract of F. virosa (FVME). The analysis was carried out using Eclipse C18 (4.6 × 100 mm, 3.5 µm) UPLC column. The optimized chromatographic condition was achieved at 0.16 mL/min flow rate using gradient system with acetonitrile and water as mobile phase. Both biomarkers were measured at λmax 235 nm in PDA detector at ambient temperature. The developed method furnished sharp and intense peaks of menisdaurin and bergenin at Rt = 2.723 and 3.068 min, respectively along with r2 > 0.99 for both. The recoveries of bergenin and menisdaurin were found in the range of 99.37–101.49% and 98.20–100.08%, respectively. With other validation data, including precision, specificity, accuracy, and robustness, this method demonstrated excellent reliability and sensitivity. The separation parameters i.e. retention, separation, and resolution factors for resolved standards (bergenin and menisdaurin) were >1, which showed good separation. The quantity of bergenin and menisdaurin in the FVME sample was found as 15.16 and 3.28% w/w, respectively. The developed UPLC-PDA method could be conveniently adopted for the routine quality control analysis. Keywords: Flueggea virosa, Phyllanthaceae, Quantitative analysis, UPLC-PDA, Bergenin, Menisdauri
Antimicrobial Activity of Dihydroisocoumarin Isolated from Wadi Lajab Sediment-Derived Fungus Penicillium chrysogenum: In Vitro and In Silico Study
Antibiotic resistance is considered a major health concern globally. It is a fact that the clinical need for new antibiotics was not achieved until now. One of the most commonly prescribed classes of antibiotics is β-Lactam antibiotics. However, most bacteria have developed resistance against β-Lactams by producing enzymes β-Lactamase or penicillinase. The discovery of new β-Lactamase inhibitors as new antibiotics or antibiotic adjuvants is essential to avoid future catastrophic pandemics. In this study, five dihydroisocoumarin: 6-methoxy mellein (1); 5,6-dihydroxymellein (2); 6-hydroxymellein (3); 4-chloro-6-hydroxymellein (4) and 4-chloro-5,6-di-hydroxymellein (5) were isolated from Wadi Lajab sediment-derived fungus Penicillium chrysogenum, located 15 km northwest of Jazan, KSA. The elucidation of the chemical structures of the isolated compounds was performed by analysis of their NMR, MS. Compounds 1–5 were tested for antibacterial activities against Gram-positive and Gram-negative bacteria. All of the compounds exhibited selective antibacterial activity against Gram-positive bacteria Staphylococcus aureus and Bacillus licheniformis except compound 3. The chloro-dihydroisocoumarin derivative, compound 4, showed potential antimicrobial activities against all of the tested strains with the MIC value between 0.8–5.3 μg/mL followed by compound 5, which exhibited a moderate inhibitory effect. Molecular docking data showed good affinity with the isolated compounds to β-Lactamase enzymes of bacteria; NDM-1, CTX-M, OXA-48. This work provides an effective strategy for compounds to inhibit bacterial growth or overcome bacterial resistance
Utilization of Waste Biomaterial as an Efficient and Eco-Friendly Adsorbent for Solid-Phase Extraction of Pantoprazole Contaminants in Wastewater
The objective of this analysis is to establish the potential of biodegradable agro-industrial waste materials as biosorbents in the solid-phase extraction (SPE) technique for sample preparation. In this regard, waste coffee husk (CH) powder was collected, washed, treated chemically, characterized, and applied as an SPE adsorbent to extract pantoprazole from the wastewater samples. Sample detection was accomplished using the UPLC-MS/MS system. The positive mode of electrospray ionization was exploited for the ionization of the sample, and quantification of the target analyte was performed by the multiple reaction monitoring modes. The precursor to product ion transition of 384.02→1380.05 and 384.02→200.05 was used as qualifiers and quantifiers, respectively. Optimization of the particle size, adsorbent dose, and contact time were evaluated to select the best combination of features. The efficiency and regeneration capability of the CH were compared with respect to a commercially available silica-based C18 SPE adsorbent, and it was found that CH possessed comparable (~50%) extraction, as well as regeneration capacity (~95%). The developed biosorbent was applied in a wastewater sample spiked with the target analyte and recovery studies were performed, which found a range of 93.0 to 102.0% with a %RSD of 3.72 to 12.7%. Thus, CH can be exploited as a ‘greener’ replacement for the commercially available adsorbents for the extraction/retention of active pharmaceutical ingredients present in water/wastewater samples