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The fabrication of crystalline COF materials with predictable structures and desirable features is one of the crystal engineering strategic goals. Many synthetic factors play an invisible role in the crystallization...

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Beta glucan (β-glucan) has promising bioactive properties. Consequently, the use of β-glucan as a food additive is favored with the dual-purpose potential of increasing the fiber content of food products and enhancing their health properties. Our aim was to evaluate the biological activity of β-glucan (antimicrobial, antitoxic, immunostimulatory, and anticancer) extracted from Saccharomyces cerevisiae using a modified acid-base extraction method. The results demonstrated that a modified acid-base extraction method gives a higher biological efficacy of β-glucan than in the water extraction method. Using 0.5 mg dry weight of acid-base extracted β-glucan (AB extracted) not only succeeded in removing 100% of aflatoxins, but also had a promising antimicrobial activity against multidrug-resistant bacteria, fungi, and yeast, with minimum inhibitory concentrations (MIC) of 0.39 and 0.19 mg/mL in the case of resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa, respectively. In addition, AB extract exhibited a positive immunomodulatory effect, mediated through the high induction of TNFα, IL-6, IFN-γ, and IL-2. Moreover, AB extract showed a greater anticancer effect against A549, MDA-MB-232, and HepG-2 cells compared to WI-38 cells, at high concentrations. By studying the cell death mechanism using flow-cytometry, AB extract was shown to induce apoptotic cell death at higher concentrations, as in the case of MDA-MB-231 and HePG-2 cells. In conclusion, the use of a modified AB for β-glucan from Saccharomyces cerevisiae exerted a promising antimicrobial, immunomodulatory efficacy, and anti-cancer potential. Future research should focus on evaluating β-glucan in various biological systems and elucidating the underlying mechanism of action.

Organic conjugated polymer dots (Pdots) are emerging as a potential photocatalyst for hydrogen evolution from water. In this work, three organic semiconducting polymer dots (Pdots) based on benzo [d][1,2,3]thiadiazole (isoBT) and surfactant-based poly(ethylene oxide) chains (Triton) are presented as photocatalysts for visible-light-driven hydrogen generation in a completely solvent-free organic system. The resulting Pdots exhibit good photocatalytic activity and excellent photocatalytic stability. Achieving high efficiency with long-term photostability is important for the future commercialization of large-scale hydrogen production. Moreover, PG6 Pdots with a 1-chloro-4-fluorobenzene moiety showed high photocatalytic efficiency with high photocatalytic stability over 100 h. Thus, the introduction of a group with high electronegativity on isoBT-based Pdots is very beneficial for promising photocatalysts in terms of efficiency and stability, even though they could be used in a wide absorption range.

N‐arylthiophene‐2‐carboxamidoxime derivatives (a‐e) were synthesized by using two methods and then subjected to thermolysis at 200–250 °C for 2 h under nitrogen atmosphere either alone or in the presence of tetralin and/or naphthalene as radical scavengers yielded imidazole, oxazole, triazine and amide derivatives. The pyrolysates from both reactions were separated with their constituents by column chromatography and analyzed then identified 1H NMR, 13C NMR and GC‐MS. A plausible mechanism is suggested through two competitive pathways involving the homolysis of N‐O and/or C‐N bonds to account for the thermolysis products.

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