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In this study, the extraction and characterization of alginic acid, the most abundant compound among brown algae were investigated. The used algae were Sargassum angustifolium from the family of brown algae native to the coasts of the Persian Gulf. The effect of temperature, time, algae mass to solvent volume ratio, and ultrasonic power on the extraction yield and ratio of monomers (M/G) was investigated using the central composite design method. Moreover, the effect of the mentioned parameters on the poly dispersity index and cytotoxic effects against breast cancer cells were also investigated. The maximum obtained extraction yield was 46 %, which was higher than those reported for algae in tropical climates. This shows the effectiveness of ultrasound in facilitating the extraction process. In addition, the minimum monomer ratio was 0.45, the minimum poly dispersity index was 2.5 and the maximum cytotoxicity for using the extract on breast cancer cell line (MCF-7) was 20.3 % (with alginic acid concentration of 250 micrograms per milliliter).

A novel imprinted biocomposite and its non-imprinted form were developed by melaminating and crosslinking of chitosan coated onto a bio-based activated carbon and characterized using FTIR, BET, FESEM-EDS and XRD. Nickel, 4-Toluenesulfonyl chloride, and glutaraldehyde were used as a template, converter of hydroxyl and amine groups to good leaving groups, and cross-linker, respectively. The factors affecting adsorptivity and imprinting factor were optimized by using the Taguchi method for the subsequent comparative adsorptivity, kinetics, isotherms, selectivity, and reusability studies of imprinted biocomposite with its non-imprinted one. The pseudo-first-order and Langmuir models were best fitted to the experimental kinetics and equilibrium isotherm data, respectively. The maximum Ni (II)) adsorptivity of 109.86 mg/g, the imprinting factor (I·F) of 5.45 and Ni (II) selectivity coefficients values of 3.13, 4.48, 3.72, 2.51 for Ni (II) toward Zn (II), Cd (II), Cu (II) and Pb (II), respectively, were obtained at optimum conditions. After five consecutive adsorption-desorption cycles, the biocomposites still presented a high adsorptivity (>83%), indicating their excellent reusability.

Heterocyclic compounds are among the most prestigious and valuable chemical molecules with diverse and magnificent applications in various sciences. Due to the remarkable and numerous properties of the heterocyclic frameworks, the development of efficient and convenient synthetic methods for the preparation of such outstanding compounds is of great importance. Undoubtedly, catalysis has a conspicuous role in modern chemical synthesis and green chemistry. Therefore, when designing a chemical reaction, choosing and or preparing powerful and environmentally benign simple catalysts or complicated catalytic systems for an acceleration of the chemical reaction is a pivotal part of work for synthetic chemists. Chitosan, as a biocompatible and biodegradable pseudo-natural polysaccharide is one of the excellent choices for the preparation of suitable catalytic systems due to its unique properties. In this review paper, every effort has been made to cover all research articles in the field of one-pot synthesis of heterocyclic frameworks in the presence of chitosan-based catalytic systems, which were published roughly by the first quarter of 2020. It is hoped that this review paper can be a little help to synthetic scientists, methodologists, and catalyst designers, both on the laboratory and industrial scales.

The aim of this study was to the production of an active film based on Prangos ferulacea root gum, using its leaf's essential oil (PFEO) (0-3 %) and bismuth oxide nanoparticles (Bi

This study examines the effect of the chemical modification of alginate (ALG) by octenyl succinic anhydride (OSA) on the physical, mechanical, and barrier properties of the alginate-zein blend film. To reach this goal, the effect of the degree of substitution (DS) of the modified-ALG (OS-ALG) was assessed on the physical, mechanical, and barrier properties of the fabricated composite films. As confirmed by FTIR and XRD, the hydrophobic nature of OS-ALG facilitated the miscibility of OS-ALG-zein than ALG-zein. Moreover, scanning electron microscope (SEM) images confirmed the FTIR and XRD results. Furthermore, the substitution of ALG with OS-ALG in the blend films can significantly improve the water resistance and mechanical strength of the samples. The OSA-modification of ALG increased the water contact angle while decreasing the solubility, moisture content, extensibility, and water vapor permeability. Finally, the OS-ALG (DS = 0.034) and zein would be considered as a new source for the fabrication of biodegradable composite films with excellent structural and barrier properties.

The effects of dielectric-barrier discharge (DBD) plasma treatment (20 s to 120 s treatment time with 40 kV, 12 kHz) induced mild oxidation on the gelling properties, and related structural changes of glycinin were investigated. The gelling ability of glycinin was improved by the mild oxidation induced by the plasma treatment. Treated glycinin gels exhibited a continuous and uniform network microstructure. Samples treated for 120 s had a 2.07-, 3.99- and 2.03-fold increase in hardness, chewiness, and resilience compared to the 20 s treated samples. Structural analyses showed that primary and secondary structures of glycinin were unaffected. The tertiary structure was shifted, accompanied by a decrease in free sulfhydryl (-SH) content. At the same time, carbonyl content and average particle diameter were increased by DBD treatment. The DBD treatment facilitated the generation/exchange of intermolecular disulfide bonds and enhanced gelling properties of glycinin. It is concluded that controlled plasma-induced protein oxidation can improve protein functionality.

Kappa-carrageenan (KC) esterification reaction with octenyl succinic anhydride was optimized using response surface methodology, leading to the production of a food-based emulsifier. Modified kappa-carrageenan (KC-OSA) with different degrees of substitution (DS) (0.023 and 0.045) was produced, and their functional and structural properties were investigated. The results from FTIR and

Although therapeutic effect of quercetin (Quer) was reported on non-alcoholic fatty liver disease (NAFLD), destructive effects have been shown on male fertility due to its pro-oxidative properties. On the other hand, NAFLD impairs germ cells to produce sperm and leads to male infertility. Herein, a biocompatible and green bigel was designed for Quer delivery to prevent infertility induced by NAFLD as the increasing complications. Bigels were prepared using cottonseed oil/cannabis oil/alginate/ferula gum and optimized by the mixture design method. NAFLD was induced by 58% of dietary calorie as lard and 42 g/l fructose for 16 weeks in Sprague-Dawley rats. So on animals received 2 mg/kg Quer loaded on bigels, free bigels, or free Quer for 45 days as daily gavage. Semen was analyzed, followed by the assessment of DNA integrity. Count, motility, and normal morphology reached the healthy control group at the bigel-Quer-treated one. Moreover, all of these parameters were significantly higher in the bigel-Quer group than the Quer and bigel, alone. The percent of sperms with head and tail abnormality decreased considerably in the bigel-Quer group compared with the Quer, free bigel, and NAFLD groups. Serum testosterone levels significantly increased and reached the healthy control group in the bigel-Quer group. DNA fragmentation of sperm significantly decreased in the bigel-Quer group (p0.05). The bigel showed synergistic effects with Quer for treating infertility in rats with NAFLD.

In this study, kefiran was esterified with octenyl succinic anhydride (OSA). The esterification reaction variables including pH (8.5), kefiran concentration (5% (w/w)), OSA concentration (12% (w/w)), temperature (~38 °C) and reaction time (~80 min) were found as optimum points to achieve the maximum degree of substitution (DS) (0.041 ± 0.002). Kefiran-OSA samples with DS of 0.021 (FDA suggested DS) and 0.041 (maximum DS) were prepared and compared with unmodified kefiran in all experiments. FTIR and 1H NMR spectroscopies proved the grafting of OSA on kefiran structure. XRD analysis revealed that with increase in DS, the physical state of kefiran to be more amorphous. In addition, the esterification modification led to a decrease in the degradation temperature and an increase in the apparent viscosity based on the obtained data from thermal analysis and viscosity measurement. The results of the foaming and emulsifying properties confirmed the improvement in surface properties of the modified kefiran. The frequency sweep test illustrated that with an increase in DS, the viscoelastic behavior of the kefiran cryogels to be more viscous. It can finally be stated that the modification with OSA was a high potential strategy to extend the industrial applications of the kefiran.

Pullulan (PU) is an exo-polysaccharide used in the food and pharmaceutical industries. However, the use of PU in different industries is limited due to its highly hydrophilic nature and consequently weakness in surface properties which can be remedied by its chemical modification with octenyl succinic anhydride (OSA). For this purpose, PU modification with OSA was optimized and the results showed that the maximum degree of substitution (0.061 ± 0.003) was obtained under pH of 9.0, pullulan concentration of 40% (w/w), temperature of ~40.90 °C, reaction time of ~101.21 min and OSA concentration of 14.96% (w/w). Also, the grafting of OSA on pullulan structure was confirmed by FTIR, 1H NMR and zeta-potential analyzes. Although this modification had no significant effect on the amorphousity of pullulan, it led to an increase in viscosity and a decrease in decomposition temperature and surface tension. Improvement of emulsifying properties of PU-OSA sample was proved by the evaluation of emulsifying capacity of un- and modified samples and also, zeta-potential, particle size and viscosity of the prepared emulsions. In line with surface characteristic results, an increase in foam capacity of modified samples was observed with decreasing the interfacial tension.

Herein, for the first time, the adsorption mechanism of HCrO4− and CrO42− (as models of Cr(VI)) by bacterial cellulose (BC), polyaniline (PANI), and BC/PANI was performed using Density Functional Theory (DFT) in both acidic and neutral pH. For this purpose, three forms of neutral, partially (pp), and fully protonated (fp) were assumed for PANI in neutral and acidic media to elucidate the influence of pH. The results indicated that the formation of hydrogen bonds (H-bond) had the main contribution in the adsorption of CrO42− and HCrO4− onto both BC and PANI. Besides, the adsorption energy of PANI was nearly 3 times as much as BC in both acidic and neutral pH. The design of the BC/PANI complex improved the stability of PANI by increasing in HOMO-LUMO energy gap from 1.1 eV to 1.97 eV. The establishment of more H-bonds, and the appearance of two different types of H-bonds, O⋯H and N⋯H, and their smaller distances (average 1.5 A), were observed in HCrO4−/BC-fp-PANI complexes, while one type of hydroxyl H-bond (average 2 A) was detected in CrO42−/BC-pp-PANI. It proved the adsorption of Cr(VI) is more favorable in acidic pH. The small value of charge transferred (−0.001–0.01) showed that interfacial interaction was governed by physisorption.

The present study synthesized a new kind of pH-responsive active targeting glycodendrimer (ATGD) for doxorubicin delivery to cancerous cells. First, the glycodendrimer was synthesized based on the cultivation of chitosan dendrons on amine-functionalized, silica-grafted cellulose nanocrystals. Afterward, glycodendrimer was conjugated with folic acid to provide a folate receptor-targeting agent. The response surface method was employed to obtain the optimum conditions for the preparation of doxorubicin-loaded ATGD. The effect of doxorubicin/ATGD ratio, temperature, and pH on doxorubicin loading capacity was evaluated, and high loading capacity was achieved under optimized conditions. After determining doxorubicin release pattern at acidic and physiological pH, ATGD cytotoxicity was surveyed by MTT assay. Based on the results, the loading behavior of doxorubicin onto ATGD was in good agreement with monolayer-physisorption, and drug release was Fickian diffusion-controlled. ATGD could release the doxorubicin much more at acidic pH than physiological pH, corresponding to pH-responsive release behavior. Results of MTT assay confirmed the cytotoxicity of doxorubicin-loaded ATGD in cancer cells, while ATGD (without drug) was biocompatible with no tangible toxicity. These results suggested that ATGD has the potential for the treatment of cancer.

A novel active LDPE/TPS nanocomposite films containing date palm seed extracts (Kabkab variety) were developed using D-optimal mixture design. 20 different blends of components including LDPE, TPS, Cloisite 20A, PE-g-MA, EDTA and date palm seed extract in different proportions were prepared. Using trace and counter plots the effects of each component on the mechanical and antibacterial properties of the composites were studied. The results showed that the films containing a mixture of date seed extract and EDTA had notable antibacterial activity against E. coli and S. aureus; however, these components weakened the mechanical properties of the prepared films. At the same time Cloisite 20A nanoparticles strengthened the films mechanical properties. The optimized formulation for the overall best antibacterial and mechanical properties was 67.5 wt% for LDPE, 4.1 wt% for date seed extract, 2.8 wt% for Cloisite 20A and 2.5 wt% for EDTA. The studied properties of the manufactured film samples were close to the values predicted by the model.

In the present study, the polymer obtained from Cydonia oblonga Miller seeds (quince seed mucilage (QSM)) in combination with polycaprolactone (PCL) was used for producing hybrid electrospun scaffolds as three-dimensional (3D) cell culture platforms. Various PCL/QSM ratios were tested to obtain a uniform product with an appropriate mean fiber diameter for cell growth. The chemical structures of the scaffolds were studied by FT-IR spectroscopy and their crystallinity was investigated by XRD. Fiber morphology studies by SEM revealed that the fiber mean diameters decrease upon increasing the QSM component of the electrospun compound. The PCL/QSM ratio of 60/40 exhibited desirable uniform bead-free nanofibers. The hydrophilicity of the scaffolds were explored by contact angle measurements, which indicated that more hydrophilic fibers are produced as the PCL/QSM ratio is decreased. Porosity and strength of the scaffolds were also studied, which showed the key role of PCL in mechanical strength of the nanofibers. The results of cell culture experiments using epithelial Vero cells on the scaffolds displayed their high capacity in cell growth and proliferation. It was revealed that the electrospun PCL/QSM based scaffolds with 3D structures and 75–150 nm mean fiber diameters are able to maximize adhesion and growth of Vero cells.

Herein, polyaniline (PANI) with tuning morphology was in-situ synthesized within bacterial cellulose (BC)/silver nanoparticles hydrogels (AgNPs) that were prepared by green hydrothermal reduction method in different molarity of 0.01 and 0.25 of HCl solution along with the presence of polyethylene glycol (PEG). The synthesis of PANI in the presence of PEG in 0.01 M HCl led to the formation of rose-like morphology within nanocomposite aerogels with a size of 1.5–5.2 μm. All aerogels had the porosity and shrinkage of higher than 80% and lower than 10%, respectively. Rheology results showed a higher value of storage modulus (G′) than that of loss modulus (G″) for all samples over the whole frequency regime. It confirmed by the loss factor (tan δ) value of less than 1 for all hydrogel samples. The synthesis of PANI within BC/Ag in 0.25 M of HCl solution resulted in a substantial rise of G′ to nearly 1.5 × 104 Pa that was one order of magnitude higher than that of other hydrogels. However, the synthesis condition of PANI did not influence the antibacterial activity. In spite of unfavorable cell attachment onto nanocomposite aerogels, the cell proliferation increased steadily over the whole period of incubation.

Bacillus licheniformis LMG 7559, which is capable of producing extracellular poly gamma- (glutamic acid) (PGA), was provided for the biopolymer synthesis. Using a modified PGA medium for PGA production, the isolated biopolymer, undergone dialysis process mainly for desalination and removal of other impurities. The bacteria produced high molecular weight biopolymers with a weight average molecular weight (Mn) of 1.6 × 105 g/mole identified by gel permeation chromatography (GPC). Furthermore, GPC analysis was utilized to determine the poly-dispersity of PGA as well as molecular weight variation by cultivation time. The heavy weight fraction of 1.85 × 105 g/mole with poly-dispersity index of 7.42 was distinguished. For the extracted and dialyzed biopolymer, thermal properties were studied using DSC/TGA by which a mass loss of 36 percent was observed. Eventually, the biopolymer solution was injected into the oil saturated heterogeneous porous medium to evaluate the recovery factor enhancement by PGA flooding. It was found that 31.45% of oil in place was recovered by biopolymer flooding, whereas only 16.6% of oil in place was obtained by water flooding.

Given the great demand for biopolymer and protein-based products from renewable resources, synthesis of a keratin-based hydrogel is presented herein. In this work, a novel hydrogel of poly(γ-glutamic acid) (γ-PGA) and keratin was synthesized through facile EDC·HCl/HOBt chemistry. Since keratin main chain is rich in amino side groups, carboxyl groups in γ-PGA were crosslinked with multi terminated amine groups in keratin. In the following, the hydrogel characteristics, including swelling ratio (2010% at molar ratio of HOBt/EDC = 0.105), in vitro degradation and mass loss (about 20% at day 21 for the aforementioned sample), chemical decomposition and the rheological properties were investigated. The chemical activator agents, enhanced the elastic modulus of swollen hydrogel from around 1000 to 4000 Pa by increasing the crosslinking degree. Despite good biocompatibility for cell growth, some kind of self-assembled keratin hydrogels are not suitable for microscopic observation while the γ-PGA-Keratin hydrogel in our study is transparent. The γ-PGA-Keratin hydrogels possess significant features of rapid hydrogel formation in seconds, maximum swelling ratio of about 2500% maximum elastic modulus (stiffness) of about 4.5 kPa (for the swollen sample) with controllable matrix pore size. For further application, the biocompatibility of the γ-PGA-Keratin hydrogel was assessed by live/dead assay. Recent studies have demonstrated the effect of hydrogel porosity, water absorbing and stiffness on cell spreading, proliferation and differentiation of mesenchymal stem cells. Bone marrow mesenchymal stem cells could be differentiated into various cell fates depending on the elastic modulus of materials they are cultured on. We carried out a statistical study (to skip the cell work labor) to predetermine the proper working span in which we can gain a hydrogel to cover all features needed to be applied for some application like cartilage repair.