Brewers’ spent grain (BSG), the major by-product of the brewery industry, has high nutritional value, making it suitable for upcycling into products such as healthy, and sustainable cookies. Nonetheless, the incorporation of BSG in cookies can impact their quality, given the increased fiber and protein content. This work explored the effect of replacing wheat flour with BSG at 50% and 75% in cookie formulations, focusing on physical, chemical, and sensory properties. The dietary fiber, lipid, and protein content of cookies improved considerably with the highest incorporation of BSG, increasing from 6.37% to 15.54%, 9.95% to 13.06%, and 9.59% to 12.29%, respectively. Conversely, moisture and water activity decreased from 11.03% to 3.37% and 0.742 to 0.506, respectively, forecasting a lower risk of microbial contamination and increased shelf-life. The incorporation of BSG in cookies resulted in decreased brightness and increased hardness, from 40 N to 97 N. Moreover, colorimetric shifts among the control cookies and the two BSG-rich formulations could be easily identified by an untrained observer. Sensory evaluation showed that cookies with 50% BSG retained acceptable sensory characteristics, suggesting potential for further development. Overall, BSG enhances the nutritional profile of cookies with no excessive detrimental impact on sensory features.

The growing demand for sustainable and efficient synthetic methodologies has brought nanocatalysis to the forefront of modern organic chemistry, particularly in the construction of heterocyclic compounds through multicomponent reactions (MCRs). Among various nanocatalysts, calcium oxide nanoparticles (CaO NPs) have gained significant attention because of their strong basicity, thermal stability, low toxicity, and cost-effectiveness. This review provides a comprehensive account of the recent strategies using CaO NPs as heterogeneous catalysts for the green synthesis of nitrogen- and oxygen-containing heterocycles through MCRs. Key reactions such as Biginelli, Hantzsch, and pyran annulations are discussed in detail, with emphasis on atom economy, reaction conditions, product yields, and catalyst reusability. In many instances, CaO NPs have enabled solvent-free or aqueous protocols with high efficiency and reduced reaction times, often under mild conditions. Mechanistic aspects are analyzed to highlight the catalytic role of surface basic sites in facilitating condensation and cyclization steps. The performance of CaO NPs is also compared with other oxide nanocatalysts, showcasing their benefits from green metrics evaluation like E-factor and turnover frequency. Despite significant progress, challenges remain in areas such as asymmetric catalysis, industrial scalability, and catalytic stability under continuous use. To address these gaps, future directions involving doped CaO nanomaterials, hybrid composites, and mechanochemical approaches are proposed. This review aims to provide a focused and critical perspective on CaO NP-catalyzed MCRs, offering insights that may guide further innovations in sustainable heterocyclic synthesis.

Interest is growing in the antimicrobial potential of the non-psychoactive cannabinoids, such as cannabidiolic acid (CBDA) and cannabigerolic acid (CBGA), and their metal systems. The present study follows on from previous potentiometric and ESI-MS studies confirming the formation of stable zinc(II) species with cannabinoid acids in an alcohol–water environment under physiological conditions. The antibacterial action of the compounds was assessed against reference Gram-negative strains (Pseudomonas aeruginosa, Escherichia coli, Proteus mirabilis) and Gram-positive strains (Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis) using minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) assays. Their cytotoxicity was also evaluated in vitro using mouse fibroblasts. The tested compounds were found to demonstrate pronounced selectivity against Gram-positive bacterial strains compared to Gram-negative bacteria. The antibacterial efficacy of the free ligands was enhanced by the presence of Zn(II) in the solution: the equilibrium mixtures exhibited greater inhibitory activity against E. faecalis and S. epidermidis, with MIC and MBC values being non-cytotoxic toward L929 fibroblasts under the tested in vitro conditions. However, Gram-negative bacteria were only found to be susceptible at elevated concentrations, which also induced cytotoxic effects. Among the free ligands, CBGA exhibited slightly stronger antibacterial activity than CBDA.