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1.
Sci Rep ; 14(1): 1848, 2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38253668

ABSTRACT

In the sugar industry, eliminating side impurities throughout the manufacturing process is the most significant obstacle to clarifying sugar solutions. Herein, magnetic chitosan (MCS) nanocomposite was Fabricated to be used as a biodegradable, environmentally friendly clarifying agent throughout the cane juice and sugar refining processes. Fe3O4 was synthesized using the coprecipitation procedure, and then MCS was combined using a cross-linking agent. Furthermore, 14.76 emu g-1 was the maximum saturation magnetization (Ms) value. Because MCS is magnetically saturated, it may be possible to employ an external magnetic field to separate the contaminant deposited on its surface. Additionally, zeta potential analysis showed outstanding findings for MCS with a maximum value of (+) 20.7 mV, with improvement in color removal % up to 44.8% using MCS with more than 24% in color removal % compared to the traditional clarification process. Moreover, utilizing MCS reduced turbidity from 167 to 1 IU. Overall, we determined that MCS nanocomposite exhibits considerable effectiveness in the clarifying process for different sugar solutions, performing as an eco-friendly bio-sorbent and flocculating material.

2.
BMC Chem ; 17(1): 77, 2023 Jul 15.
Article in English | MEDLINE | ID: mdl-37454143

ABSTRACT

Modifying the metal surface is one solution to the industry's growing corrosion problem. Thus, via threading approach and insertion of copolymers (CoP5-7) containing polyarylidenes through the internal cavity beta-cyclodextrin ß-CD, novel pseudopolyrotaxanes copolymers (PC5-7) are developed, resulting in mild steel corrosion inhibition. Inhibitors of corrosion based on ß-CD molecules adsorb strongly to metal surfaces because of their many polar groups, adsorption centers, many linkages of side chains, and benzene rings. The corrosion inhibition efficiencies IE % statistics have been revised via the Tafel polarization method and Spectroscopy based on the electrochemical impedance (EIS), with PC7 achieving the highest 99.93% in 1.0 M H2SO4; they are mixed-type inhibitors. The chemical composition of the resulting PCs is determined with Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) is utilized to examine the morphological structure of the produced polymers, and X-ray diffraction is employed to identify crystallinity. Encapsulating CoP5-7 with ß-CD changes the morphological structures and increases the generated PCs' crystallinity. The thermal stability of PCs is studied, indicating the presence of these CoPs within the ß-CD cavities enhances their thermal stability. This research will be a stepping stone for developing high-efficiency anti-corrosion coatings and various industrial applications.

3.
Chem Asian J ; 18(10): e202300215, 2023 May 16.
Article in English | MEDLINE | ID: mdl-37010444

ABSTRACT

1,3-Dipolar cycloaddition through in situ generation of azomethine ylide provides a straightforward and critically important sustainable approach for access to diverse pyrrolidine chemical space. Herein, we developed a metal-free AcOH-activated 1,3-dipolar cycloaddition protocol that permits the synthesis of uncommon pyrrolidine cycloadducts with excellent diastereoselectivity. The challenging substrates of 3-formylchromone, glycine ester.HCl and arylidene dipolarophile were reacted in the presence of AcONa, which played a dual role as a base and AcOH source, to deliver firstly endo-cycloadduct. Under prolonged reaction time at room temperature or heating; the endo-adduct underwent diastereodivergent via a sequence of retro-cycloaddition, stereomutation of the generated syn-dipole into anti-dipole and recycloaddition; to furnish the scarcely known exo'-cycloadduct with high diastereodivergency. The reaction worked well with a broad range of substrates and the stereochemistry of the obtained cycloadducts was determined without ambiguity using NMR- and X-ray analysis. Experimental and theoretical DFT calculation studies were performed to support the proposed reaction mechanism and elucidate the key role of AcOH in the process which seems more beneficial than other transition metal-catalyzed processes.

4.
Food Chem ; 415: 135603, 2023 Jul 30.
Article in English | MEDLINE | ID: mdl-36870210

ABSTRACT

The present paper aims to use natural biodegradable polymers of chitosan (CS) and cellulose (CEL) to synthesize green chitosan-cellulose (CS-CEL) nanocomposite as a new clarifying agent. This is the cutting-edge of the sugar industry's clarification process. The CS-CEL nanocomposite showed outstanding results in zeta potential analysis, with a maximum value (+) 57.73 mV, leading to remarkableresults in coloradsorption via electrostatic attraction. It was also observed that CS-CEL has high mechanical stability. When CS and CS-CEL nanocomposite were used in the clarification of sugarcane (MJ), the findings demonstrated an improvement in colorremoval of up to 8.7% using CS and 18.1%using CS-CEL nanocomposite compared to currently phosphotation clarification process. Also, Turbidity decreased using CS-CEL nanocomposite compared to the traditional phosphotation clarification process. Overall, we can conclude that CS-CEL nanocomposite has considerable efficiency in sugarcane juice clarification process as a green biodegradable adsorbent and flocculating material to produce sulfur-free sugar.


Subject(s)
Chitosan , Nanocomposites , Cellulose , Sugars
5.
Int J Biol Macromol ; 219: 1062-1079, 2022 Oct 31.
Article in English | MEDLINE | ID: mdl-35944757

ABSTRACT

In this paper, chitosan (Chi) was successfully reacted with natural mono ketone namely, camphor (Cam), through a condensation reaction to obtain a novel Chi-Cam polymer. The encapsulation of Chi-Cam polymer into the cavity of ß-cyclodextrin biopolymer by inclusion complex method, and the immobilization of TiO2 NPs into Chi-Cam matrix by metal complex method were performed. A set of characterizations (XRD, FTIR, SEM, UV-Vis., optical band gap, Urbach energy, refractive index, and thermogravimetric analysis) were implemented to incorporate their properties with applications. It was not observed the existence of any strange peaks in diffractogram patterns of all prepared samples, confirming the proper preparation and high purity polymers. The crystalline index was found to be 69.41, 41.58, 58.25 and 44.2 % for Chi, Chi-Cam, polyrotaxane, and nanocomposite, respectively. High surface area, lowest pores size, and lowest pores volume were confirmed the micropores of composite, which also could provide more reactive sites, and enhancing the bioactivity. The tested Chi-Cam/TiO2 NPs possessed the highest antimicrobial impact, followed by the Chi-Cam/ß-CD towards pathogenic microbes. The highest % inhibition of biofilm formation by Chi-Cam, Chi-Cam/ß-CD, and Chi-Cam/TiO2 NPs was noted for S. aureus (40.05 %, 80.21 %, and 87.49 %), E. coli (38.56 %, 74.32 % and 83.32 %), P. aureginosa (32.12 %, 58.80 %, and 74.53 %), and C. albicans (13.69 %, 27.89 % and 70.89 %), respectively. The obtaining findings pave the route towards useful utilization of potential materials for biomedical applications.


Subject(s)
Anti-Infective Agents , Chitosan , Nanoparticles , Rotaxanes , beta-Cyclodextrins , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Biofilms , Camphor/pharmacology , Cellulose , Chitosan/chemistry , Chitosan/pharmacology , Cyclodextrins , Escherichia coli , Nanoparticles/chemistry , Polymers/pharmacology , Staphylococcus aureus , Titanium/chemistry , Titanium/pharmacology , beta-Cyclodextrins/pharmacology
6.
Polymers (Basel) ; 14(2)2022 Jan 06.
Article in English | MEDLINE | ID: mdl-35054634

ABSTRACT

Polymers and their composites have recently attracted attention in both pharmaceutical and biomedical applications. Polyethylene glycol (PEG) is a versatile polymer extensively used in medicine. Herein, three novel PEG-based polymers that are pseudopolyrotaxane (PEG/α-CD) (1), titania-nanocomposite (PEG/TiO2NPs) (2), and pseudopolyrotaxane-titania-nanocomposite (PEG/α-CD/TiO2NPs) (3), were synthesized and characterized. The chemical structure, surface morphology, and optical properties of the newly materials were examined by FT-IR, 1H-NMR, SEM, and UV-Vis., respectively. The prepared polymers were used as drug carriers of sulfaguanidine as PEG/α-CD/Drug (4), PEG/TiO2NPs/Drug (5), and PEG/α-CD/TiO2NPs/Drug (6). The influence of these drug-carrying formulations on the physical and chemical characteristics of sulfaguanidine including pharmacokinetic response, solubility, and tissue penetration was explored. Evaluation of the antibacterial and antibiofilm effect of sulfaguanidine was tested before and after loading onto the prepared polymers against some Gram-negative and positive bacteria (E. coli, Pseudomonas aeruginosa, and Staphylococcus aureus (MRSA)), as well. The results of this work turned out to be very promising as they confirmed that loading sulfaguanidine to the newly designed polymers not only showed superior antibacterial and antibiofilm efficacy compared to the pure drug, but also modified the properties of the sulfaguanidine drug itself.

7.
Acta Chim Slov ; 65(4): 787-794, 2018 Dec.
Article in English | MEDLINE | ID: mdl-33562943

ABSTRACT

Reaction of isonicotinaldehyde with 2-cyanoacetohydrazide afforded (E)-2-cyano-N'-(pyridin-4-ylmethylene)acetohydrazide (1). Compound 1 was used as the precursor for the synthesis of novel pyridine derivatives by reaction with different arylidene malononitriles, malononitrile and acetylacetone to give pyridine derivatives 5a-e, 6 and 7, respectively. 4,4'-Bipyridine derivatives 9a-d were synthesized by a three-component reaction of isonicotinaldehyde, 2-cyanoacetohydrazide and activated nitriles 8a-d. Treatment of compound 9a with different aromatic aldehydes gave [1,2,4]triazolo[1,5-a]pyridine derivatives 11a-c. All reaction products were characterized by analytical and spectral data. For the novel compounds their bioactivity as antitumor agents was examined for in vitro cytotoxicity against HepG-2 and MCF-7. It was found that compounds 9a and 9b have high cytotoxic activity against both HepG-2 and MCF-7.

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