Fabrication and characterization of a new eco-friendly sulfonamide-chitosan derivative with enhanced antimicrobial and selective cytotoxicity properties.

Chitosan (CH) exhibits low antimicrobial activity. This study addresses this issue by modifying the chitosan with a sulfonamide derivative, 3-(4-(N,N-dimethylsulfonyl)phenyl)acrylic acid. The structure of the sulfonamide-chitosan derivative (DMS-CH) was confirmed using Fourier transform infrared spectroscopy and Nuclear magnetic resonance. The results of scanning electron microscopy, thermal gravimetric analysis, and X-ray diffraction indicated that the morphology changed to a porous nature, the thermal stability decreased, and the crystallinity increased in the DMS-CH derivative compared to chitosan, respectively. The degree of substitution was calculated from the elemental analysis data and was found to be moderate (42%). The modified chitosan exhibited enhanced antimicrobial properties at low concentrations, with a minimum inhibitory concentration (MIC) of 50 µg/mL observed for B. subtilis and P. aeruginosa, and a value of 25 µg/mL for S. aureus, E. coli, and C. albicans. In the case of native chitosan, the MIC values doubled or more, with 50 µg/mL recorded for E. coli and C. albicans and 100 µg/mL recorded for B. subtilis, S. aureus, and P. aeruginosa. Furthermore, toxicological examinations conducted on MCF-7 (breast adenocarcinoma) cell lines demonstrated that DMS-CH exhibited greater toxicity (IC50 = 225.47 µg/mL) than pure CH, while still maintaining significant safety limits against normal lung fibroblasts (WI-38). Collectively, these results suggest the potential use of the newly modified chitosan in biomedical applications.

Synthesis, characterization, and biological evaluation of new chitosan derivative bearing diphenyl pyrazole moiety.

This work reports the synthesis of a new pyrazole derivative by reacting 5-amino-1,3-diphenyl pyrazole with succinic anhydride and bearing the product chemically on the chitosan chains via amide linkage to achieve a new chitosan derivative (DPPS-CH). The prepared chitosan derivative was analyzed by IR, NMR, elemental analysis, XRD, TGA-DTG, and SEM. As compared with chitosan, DPPS-CH showed an amorphous and porous structure. Coats-Redfern results showed that the thermal activation energy for the first decomposition of DPPS-CH is 43.72 KJ mol-1 lower than that required for chitosan (88.32 KJ mol-1), indicating the accelerating effect of DPPS on the thermal decomposition of DPPS-CH. The DPPS-CH manifested a powerful wide spectrum antimicrobial potential against pathogenic gram-positive and gram-negative bacteria and Candida albicans at minute concentrations (MIC = 50 µg mL-1) compared to chitosan (MIC = 100 µg mL-1). The MTT assay proved the toxic properties of DPPS-CH against a cancer cell line (MCF-7) at a minute concentration (IC50 = 15.14 µg mL-1) while affecting normal cells (WI-38) at seven times this concentration (IC50 = 107.8 µg mL-1). According to the current findings, the chitosan derivative developed in this work appears to be a promising material for use in biological domains.

Exploring the antimicrobial, antioxidant, anticancer, biocompatibility, and larvicidal activities of selenium nanoparticles fabricated by endophytic fungal strain Penicillium verhagenii.

Herein, four endophytic fungal strains living in healthy roots of garlic were used to produce selenium nanoparticles (Se-NPs) via green synthesis. Penicillium verhagenii was found to be the most efficient Se-NPs producer with a ruby red color that showed maximum surface plasmon resonance at 270 nm. The as-formed Se-NPs were crystalline, spherical, and well-arranged without aggregation, and ranged from 25 to 75 nm in size with a zeta potential value of -32 mV, indicating high stability. Concentration-dependent biomedical activities of the P. verhagenii-based Se-NPs were observed, including promising antimicrobial activity against different pathogens (Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, Candida albicans, C. glabrata, C. tropicalis, and C. parapsilosis) with minimum inhibitory concentration (MIC) of 12.5-100 µg mL-1. The biosynthesized Se-NPs showed high antioxidant activity with DPPH-scavenging percentages of 86.8 ± 0.6% at a concentration of 1000 µg mL-1 and decreased to 19.3 ± 4.5% at 1.95 µg mL-1. Interestingly, the Se-NPs also showed anticancer activity against PC3 and MCF7 cell lines with IC50 of 225.7 ± 3.6 and 283.8 ± 7.5 µg mL-1, respectively while it is remaining biocompatible with normal WI38 and Vero cell lines. Additionally, the green synthesized Se-NPs were effective against instar larvae of a medical insect, Aedes albopictus with maximum mortality of 85.1 ± 3.1, 67.2 ± 1.2, 62.10 ± 1.4, and 51.0 ± 1.0% at a concentration of 50 µg mL-1 for I, II, III, and IV-instar larva, respectively. These data highlight the efficacy of endophytic fungal strains for cost-effective and eco-friendly Se-NPs synthesis with different applications.

New thiadiazole modified chitosan derivative to control the growth of human pathogenic microbes and cancer cell lines.

The emergence of multidrug-resistant microbes and the propagation of cancer cells are global health issues. The unique properties of chitosan and its derivatives make it an important candidate for therapeutic applications. Herein, a new thiadiazole derivative, 4-((5-(butylthio)-1,3,4-thiadiazol-2-yl) amino)-4-oxo butanoic acid (BuTD-COOH) was synthesized and used to modify the chitosan through amide linkages, forming a new thiadiazole chitosan derivative (BuTD-CH). The formation of thiadiazole and the chitosan derivative was confirmed by FT-IR, 1H/13C-NMR, GC-MS, TGA, Elemental analysis, and XPS. The BuTD-CH showed a high antimicrobial effect against human pathogens Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, and Candida albicans with low MIC values of 25-50 µg ml-1 compared to unmodified chitosan. The in-vitro cytotoxicity of BuTD-CH was evaluated against two cancer cell lines (MCF-7 and HepG2) and one normal cell (HFB4) using the MTT method. The newly synthesized derivatives showed high efficacy against cancerous cells and targeted them at low concentrations (IC50 was 178.9 ± 9.1 and 147.8 ± 10.5 µg ml-1 for MCF-7 and HepG2, respectively) compared with normal HFB4 cells (IC50 was 335.7 ± 11.4 µg ml-1). Thus, low concentrations of newly synthesized BuTD-CH could be safely used as an antimicrobial and pharmacological agent for inhibiting the growth of human pathogenic microbes and hepatocellular and adenocarcinoma therapy.

Alleviate the Drought Stress on Triticum aestivum L. Using the Algal Extracts of Sargassum latifolium and Corallina elongate Versus the Commercial Algal Products.

Herein, two seaweed extracts (Sargassum latifolium and Corallina elongate), and two commercial seaweed products (Canada power and Oligo-X) with a concentration of 5% were used to alleviate the drought stress on wheat plants. The extract of C. elongate had the highest capacity to ameliorate the deleterious effects of water scarcity followed by S. latifolium and the commercial products. The drought stress reduced wheat shoots length and the contents of pigments (chlorophyll and carotenoids), carbohydrates, and proteins. While the highest increment in the total carbohydrates and protein contents of the wheat shoot after two stages, 37-and 67-days-old, were noted in drought-stressed plants treated with C. elongate extract with values of (34.6% and 22.8%) and (51.9% and 39.5%), respectively, compared to unstressed plants. Decreasing the activity of antioxidant enzymes, peroxidase, superoxidase dismutase, and polyphenol oxidase in drought-stressed plants treated with algal extracts indicated amelioration of the response actions. Analysis of phytohormones in wheat plants exhibited increasing GA3 and IAA contents with percentages of (20.3-13.8%) and (72.7-25%), respectively. Interestingly, all morphological and metabolic characteristics of yield were improved due to the algal treatments compared with untreated drought-stressed plants. Overall, the algal extracts, especially those from seaweed of C. elongate, could represent a sustainable candidate to overcome the damage effects of water deficiency in the wheat plant.

Light enhanced the antimicrobial, anticancer, and catalytic activities of selenium nanoparticles fabricated by endophytic fungal strain, Penicillium crustosum EP-1.

Selenium nanoparticles (Se-NPs) has recently received great attention over owing to their superior optical properties and wide biological and biomedical applications. Herein, crystallographic and dispersed spherical Se-NPs were green synthesized using endophytic fungal strain, Penicillium crustosum EP-1. The antimicrobial, anticancer, and catalytic activities of biosynthesized Se-NPs were investigated under dark and light (using Halogen tungsten lamp, 100 Watt, λ > 420 nm, and light intensity of 2.87 W m-2) conditions. The effect of Se-NPs was dose dependent and higher activities against Gram-positive and Gram-negative bacteria as well different Candida spp. were attained in the presence of light than obtained under dark conditions. Moreover, the viabilities of two cancer cells (T47D and HepG2) were highly decreased from 95.8 ± 2.9% and 93.4 ± 3.2% in dark than those of 84.8 ± 2.9% and 46.4 ± 3.3% under light-irradiation conditions, respectively. Significant decreases in IC50 values of Se-NPs against T47D and HepG2 were obtained at 109.1 ± 3.8 and 70.4 ± 2.5 µg mL-1, respectively in dark conditions than 19.7 ± 7.2 and 4.8 ± 4.2 µg mL-1, respectively after exposure to light-irradiation. The photoluminescence activity of Se-NPs revealed methylene blue degradation efficiency of 89.1 ± 2.1% after 210 min under UV-irradiation compared to 59.7 ± 0.2% and 68.1 ± 1.03% in dark and light conditions, respectively. Moreover, superior stability and efficient MB degradation efficiency were successfully achieved for at least five cycles.

Enhanced Antimicrobial, Cytotoxicity, Larvicidal, and Repellence Activities of Brown Algae, Cystoseira crinita-Mediated Green Synthesis of Magnesium Oxide Nanoparticles.

Herein, the metabolites secreted by brown algae, Cystoseira crinita, were used as biocatalyst for green synthesis of magnesium oxide nanoparticles (MgO-NPs). The fabricated MgO-NPs were characterized using UV-vis spectroscopy, Fourier transforms infrared spectroscopy (FT-IR), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy linked with energy-dispersive X-ray (SEM-EDX), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Data showed successful formation of crystallographic and spherical MgO-NPs with sizes of 3-18 nm at a maximum surface plasmon resonance of 320 nm. Moreover, EDX analysis confirms the presence of Mg and O in the sample with weight percentages of 54.1% and 20.6%, respectively. Phyco-fabricated MgO-NPs showed promising activities against Gram-positive bacteria, Gram-negative bacteria, and Candida albicans with MIC values ranging between 12.5 and 50 µg mL-1. The IC50 value of MgO-NPs against cancer cell lines (Caco-2) was 113.4 µg mL-1, whereas it was 141.2 µg mL-1 for normal cell lines (Vero cell). Interestingly, the green synthesized MgO-NPs exhibited significant larvicidal and pupicidal activity against Musca domestica. At 10 µg mL-1 MgO-NPs, the highest mortality percentages were 99.0%, 95.0%, 92.2%, and 81.0% for I, II, III instars' larvae, and pupa of M. domestica, respectively, with LC50 values (3.08, 3.49, and 4.46 µg mL-1), and LC90 values (7.46, 8.89, and 10.43 µg mL-1), respectively. Also, MgO-NPs showed repellence activity for adults of M. domestica at 10 µg mL-1 with 63.0%, 77.9%, 84.9%, and 96.8% after 12, 24, 48, and 72 h, respectively.

Multifunctional Aspects of the Synthesized Pyrazoline Derivatives for AP1 5L X60 Steel Protection Against MIC and Acidization: Electrochemical, In Silico, and SRB Insights.

The inhibitory impact of low-cost synthesized pyrazoline derivatives named Pz series (Pz1 and Pz2) on the corrosion of API 5L X60 carbon steel in 5 M HCl was inspected to serve as corrosion inhibitors against such a solution for its usage in the oilfield well acidization process. Also, the same compounds were unitized as biocides for sulfate-reducing bacteria (SRBs) to inhibit the microbial-induced corrosion effect. This study was conducted via several electrochemical techniques, namely, electrochemical potentiodynamic polarization (EP) and electrochemical impedance spectroscopy (EIS), in addition to computational density functional theory (DFT). The inhibition efficiency (IE) of Pz series on the corrosion of 5L X60 carbon steel in 5 M HCl was found to increase whenever the Pz series molecule concentration was increased. EP measurements revealed that Pz1 and Pz2 have both cathodic and anodic features (mixed inhibitor) and their corrosion IEs were around 90%. The physicochemical properties of the Pz1 and Pz2 compounds were studied using Langmuir adsorption isotherms, where the equilibrium adsorption data were found to follow it accurately. EIS outputs were found to comply with the values obtained from EP. Scanning electron microscopy was used to examine the topographic anisotropy between the inhibited and uninhibited 5L X60 carbon steel samples to double-check the electrochemical findings. DFT calculations and Monte Carlo simulations were utilized to predict the behavior of inhibitors and to rationalize the experimental results. The serial dilution bioassay technique was used to assess the Pz series as potential biocides to counter the effect of SRBs in compliance with the TM0194-2014-SG standard test method, and the results showed the potency of Pz series in inhibiting such bacterial growth.

Endophytic Streptomyces laurentii Mediated Green Synthesis of Ag-NPs with Antibacterial and Anticancer Properties for Developing Functional Textile Fabric Properties.

Improvement of the medical textile industry has received more attention recently, especially with widespread of microbial and viral infections. Medical textiles with new properties, such as bacterial pathogens self-cleaning, have been explored with nanotechnology. In this study, an endophytic actinomycetes strain of Streptomyces laurentii R-1 was isolated from the roots of the medicinal plant Achillea fragrantissima. This is used as a catalyst for the mediated biosynthesis of silver nanoparticles (Ag-NPs) for applications in the textile industry. The biosynthesized Ag-NPs were characterized using UV-vis spectroscopy, Fourier transform infrared (FT-IR), transmission electron microscopy (TEM), and X-ray Diffraction (XRD), which confirmed the successful formation of crystalline, spherical metal nanoparticles. The biosynthesized Ag-NPs exhibited broad-spectrum antibacterial activity. Our data elucidated that the biosynthesized Ag-NPs had a highly cytotoxic effect against the cancerous caco-2 cell line. The selected safe dose of Ag-NPs for loading on cotton fabrics was 100 ppm, regarding their antibacterial activity and safe cytotoxic efficacy. Interestingly, scanning electron microscope connected with energy dispersive X-ray spectroscopy (SEM-EDX) of loaded cotton fabrics demonstrated the smooth distribution of Ag-NPs on treated fabrics. The obtained results highlighted the broad-spectrum activity of nano-finished fabrics against pathogenic bacteria, even after 5 and 10 washing cycles. This study contributes a suitable guide for the performance of green synthesized NPs for utilization in different biotechnological sectors.

Novel Technique of Pneumatic Posterior Capsulorhexis for Treatment and Prevention of Posterior Capsular Opacification.

PURPOSE: To evaluate a new technique of posterior capsulorhexis using air support to treat primary posterior capsular opacification (PCO) during cataract extraction surgery or to prevent postoperative PCO. SETTING: (1) Ophthalmology department, Faculty of Medicine, Minia University, 61519, El-Minia, Egypt. (2) Security Forces Hospital, Ophthalmology Department, Riyadh, Kingdom of Saudi Arabia. DESIGN: Prospective, randomized, consecutive case comparative non controlled study. METHODS: One hundred eyes of 100 patients with a mean age of 63.3 years with dense cataract were enrolled in the study. Fifty of them (group (1)) were with primary PCO (discovered during the operations) and fifty (group (2)) with clear posterior capsule. All of the patients underwent phacoemulsification and posterior capsulorhexis using the air to support the posterior capsule. Then, IOL implantations were done between the anterior and posterior capsular rims. Postoperatively, each patient was evaluated for the following: visual acuity (UCVA and BCVA), manifest refractive spherical equivalent (MRSE), intraocular pressure, intraocular lens (IOL) stability, visual axis opacification, and posterior segment complications as retinal breaks, retinal detachment, or cystoid macular edema (CME). RESULTS: There were no significant differences in UCVA, BCVA, and MRSE. All cases had a clear visual axis, with stable IOL and normal IOP during the follow-up period without posterior segment complications. The VA improved significantly throughout the follow-up periods in both groups without significant clinical difference. CONCLUSION: Pneumatic posterior capsulorhexis is a new effective technique for the treatment of primary PCO in dense cataract and for prevention of postoperative PCO with the good visual outcomes and minimal complications. This trial is registered with NCT04007965.