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Rhizoctonia solani Kühn and Sclerotium rolfsii Sacc. are the primary soil-borne plant diseases responsible for significant reductions in global crop yields. The primary goal of this study was to investigate the antifungal potentials of clove essential oil (CEO), nanoemulsion form (CEONE) and chitosan/nanoemulsion nanocomposite (CS/CEONE) against R. solani and S. rolfsii through in vitro and in vivo trials. Both CEONE and CS/CEONE were prepared and investigated for their physical chemical and morphological characterization. The poisoned medium method was utilized to evaluate the inhibitory effects of CEO, CEONE and CS/CEONE on the mycelial growth and enzymatic activity of R. solani and S. rolfsii. The changes of hyphae of R. solani and S. rolfsii in response to treating with CEONE and CS/CEONE were observed with scanning electron microscope (SEM). The results revealed that CEONE have larger size 86 ± 3 nm and a broader range of PDI 0.121 ± 0.011 on the average. While, CS/CEONE has smaller size of 49 ± 4 nm and narrower PDI of 0.099 ± 0.009. Both nanoemulsions had uniform spherical nanodroplets form and exhibited acidic nature. Fourier Transform Infrared Spectroscopy (FTIR) and UV-Visible Spectroscopy (UV-Vis) verified the successful incorporation of both CS and CEO within the nanoemulsion system. The results demonstrated a sustained and prolonged release profile from CS/CEONE for up to 4 days. The inhibitory effect of CEONE and CS/CEONE showed dose-dependent activity against mycelial growth of both fungi. CEONE and CS/CEONE at concentration 500 µL/L exhibited the strongest inhibition with a significant (p < 0.05) variation among them with value ranging from 56.11% to 71.94% and 52.2% to 79.2%, respectively. Comparing to control, CS/CEONE revealed the highest inhibitory effect against S. rolfsii after 96 h followed by CEONE with value reached 50.6% and 44.1%, respectively. The antifungal activity of the nanoemulsion showed strain–dependent behavior, where S. rolfsii was the most affected. SEM images showed changes in the hyphal structure of S. rolfsii and R. solani resulting from the impact of CEONE and CS/CEONE. Activity of pectinase and cellulase secreted by both fungi was also negatively affected by CEO, CEONE and CS/CEONE at all tested concentrations. Greenhouse trials revealed that increasing the concentrations of CEO, CEONE, and CS/CEONE from 50 to 500 μL/L gradually increased their effectiveness in reducing the DI% and DS% of black scurf, stem canker, pre-damping off, and post-damping off diseases on potato. The results suggest that incorporation of CS to CEONE enhanced its activity and can be utilized as a secure and non-toxic nanocomposite. Supplementary Material Supplementary Material File [ABSTRACT FROM AUTHOR]

A significant number of deaths are reported annually worldwide due to microbial and viral infections. The development of protective medical textiles for patients and healthcare professionals has attracted many researchers' attention. Therefore, this study aims to develop smart drug-eluting nanofibrous matrices to be used as a basic material for medical textile fabrication. First, chitosan/gelatin nanofibers were selected as the basic material owing to the wide antimicrobial activity of chitosan and the capability of gelatin to be hydrolyzed in the abundance of the papain-like protease (PLpro) enzyme secreted by SARS-CoV-2. Daclatasvir (DAC), an NS5A inhibitor, was selected as the model drug based on in silico studies where it showed high anti-SARS-CoV-2 potential compared to FDA-approved references. Due to their reported antimicrobial and antiviral activities, ZnO NPs were successfully prepared and incorporated with daclatasvir in chitosan/gelatin nanofibrous matrices through electrospinning. Afterward, an in vitro release study in a simulated buffer revealed the controlled release of DAC over 21 days from the nanofibers compared to only 6 h for free DAC. On the other hand, the abundance of PLpro induced the complete release of DAC from the nanofibers in only 4–8 h. Finally, the nanofibers demonstrated a wide antimicrobial activity against S. aureus, E. coli, and C. albicans. [ABSTRACT FROM AUTHOR]

This study aims at preparing propranolol-loaded trehalosomes (a trehalose-coated liposome) to be used as an antiproliferative agent for treating skin cancer. A factorial design was used to select the optimum formula, where trehalose, lecithin, and Tween 80 levels were studied. A total of 24 runs were prepared and characterized according to size, charge, entrapment efficiency, and release after 3 h to select the optimum formula. The optimized formula was investigated using TEM, DSC, and FTIR. Cell studies were carried out against the human melanoma cell line to measure cytotoxicity, apoptosis/necrosis, and cell cycle arrest. In silico studies were conducted to understand the interaction between propranolol and the influential receptors in melanoma. The results showed the selected formula consisted of trehalose (175 mg), lecithin (164 mg), and Tween 80 (200 mg) with a size of 245 nm, a charge of −9 mV, an EE% of 68%, and a Q3 of 62%. Moreover, the selected formula has good cytotoxicity compared to the free drug due to the synergistic effect of the drug and the designed carrier. IC50 of free propranolol and the encapsulation of propranolol were 17.48 μg/mL and 7.26 μg/mL, respectively. Also, propranolol and the encapsulation of propranolol were found to significantly increase early and late apoptosis, in addition to inducing G1 phase cell cycle arrest. An in silico virtual study demonstrated that the highest influential receptors in melanoma were the vitamin D receptor, CRH-R1, VEGFR 1, and c-Kit, which matches the results of experimental apoptotic and cell cycle analysis. In conclusion, the selected formula has good cytotoxicity compared to the free drug due to the synergistic effect of the drug and the designed carrier, which make it a good candidate as an antiproliferative agent for treating skin cancer. [ABSTRACT FROM AUTHOR]

Ferrocenylamine complexes have found increasing applications in the fields of catalysis in various organic reactions, industry, medical treatments and enzyme–activity determinations. Therefore, information related to the thermal and thermo-oxidative stability of these compounds is important for such applications; however, this information is currently limited. Twenty previously prepared palladium and platinum ferrocenylamine complexes with systematic structural variations are examined for their thermal (under nitrogen) and thermo-oxidation stability (under atmospheric air) using thermogravimetry (TG), differential thermal analysis (DTG), and differential scanning calorimetry (DSC) techniques. Degradation products are identified by comparing thermogravimetric analysis and theoretical calculations. Structure–stability studies are also discussed. The results show that all the compounds have high thermal and thermo-oxidative stabilities of up to 265 and 173 °C, respectively. Electron–donating substituents enhance the thermal and thermo-oxidative stabilities of the palladium complexes (t -Bu, selenide electrophiles and dielectrophiles), while those with destabilizing effects are aromatic substituents (Ph and tolyl). Most platinum ferrocenylamine sulfides and selenides show higher thermal and thermo-oxidative stabilities than their corresponding palladium analogs. All the prepared compounds show high thermal and thermo-oxidative stability which reinforces their catalytic and industrial applications. However, their thermal stability is higher than their thermo-oxidative stability. [ABSTRACT FROM AUTHOR]

DFT calculations were performed on nine flavones and flavonols to explain their high antioxidant activity and variations in their activity. Conformational analysis showed that only flavonols with 3-OH directed toward the B-ring are nonplanar; however, flavones and resulted radicals are planar. Hydroxyl group eligible for dissociation is the one with ortho OH directed toward it; otherwise, one of B-ring (in 2′ or 4′-position) hydroxyl group. There are two main factors responsible for stabilizing the resulted radicals and lowering the bond dissociation energy and hence there were found well correlated with the experimental activity. First, driving force resulted from the conversion of nonplanar flavonols to planar radicals accompanied by resonance toward the carbonyl group and H-bond formation with 3-OH and second, radical stabilization by H-bond with ortho hydroxyl group with resonance toward carbonyl or pyrone oxygen. All resonance and H-bonds were confirmed by spin density, bond length, and molecular orbital calculations. [ABSTRACT FROM AUTHOR]

Aim: This study involves, for the first time, the development of mucoadhesive biodegradable polymeric-multilayered nanoparticles-in-nanofibers (NPs-in-NFs) matrix as an innovative single-dose noninvasive ocular-insert that could substitute conventional ocular dosage-forms. Materials & methods: Azithromycin-loaded poly(lactic-co-glycolic acid) copolymer/pluronic NPs were developed then incorporated into electrospun polyvinylpyrrolidone NFs, and tested for their efficient treatment of ocular bacterial infection. Results: Release and permeation studies proved the ability of the insert to control drug release over 10 days. Conclusion: The incorporation of NPs into NFs achieved several other benefits like increasing ocular residence and contact time with conjunctival tissue, accurate dose delivery, sustaining drug release with constant rate, reducing frequency of administration, improving bioavailability along with decreasing incidence of visual and systemic side effects. [ABSTRACT FROM AUTHOR]

Antioxidant activity of anthocyanidins is greatly affected by the 3-hydroxyl group and/or a catecholic moiety. The two-hydrogen atom donation process is frequently used to explain the high antioxidant activity of polyphenolic compounds leading to the formation of stable diketones e.g. 1,2-quinones. Thermodynamic parameters, HOMO and spin density were computed to identify the favoured path, either through the 3-hydroxyl group or through the catecholic moiety in a series of catecholic and non-catecholic 3-oxy- (and deoxy)-anthocyanidins. DFT calculations showed that the donation process in non-catecholic anthocyanidins depended on the substituents on ring B. Anthocyanidins with 3′,5′-diOMe groups showed donation through 3,4′-OH or, otherwise, through 3,5-OH groups. Catecholic 3-oxyanthocyanidins, on the other hand, showed donation through the 3,4′-OH path rather than the catecholic path (4′,3′-path). The 3,4′-path was favoured by the formation of planar 3-radicals in the first step and the stabilization of 4′-radicals in the second step by H-bonding with the 3′-OH group. [ABSTRACT FROM AUTHOR]