The current values for metabolizable energy of macronutrients were proposed in 1910. Since then, however, efforts to revise these values have been practically absent, creating a crucial need to carry out a critical analysis of the experimental methodology and results that form the basis of these values. Presented here is an exhaustive analysis of Atwater’s work on this topic, showing evidence of considerable weaknesses that compromise the validity of his results. These weaknesses include the following: (1) the doubtful representativeness of Atwater’s subjects, their activity patterns, and their diets; (2) the extremely short duration of the experiments; (3) the uncertainty about which fecal and urinary excretions contain the residues of each ingested food; (4) the uncertainty about whether or not the required nitrogen balance in individuals was reached during experiments; (5) the numerous experiments carried out without valid preliminary experiments; (6) the imprecision affecting Atwater’s experimental measurements; and (7) the numerous assumptions and approximations, along with the lack of information, characterizing Atwater’s studies. This review presents specific guidelines for establishing new experimental procedures to estimate more precise and/or more accurate values for the metabolizable energy of macronutrients. The importance of estimating these values in light of their possible dependence on certain nutritional parameters and/or physical activity patterns of individuals is emphasized. The use of more precise values would allow better management of the current overweight and obesity epidemic.

The current medical need to respond to different diseases has sparked great interest in extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) due to their great regenerative potential and as drug carriers by playing a critical role in cell–cell communication. However, due to their heterogeneity, there is no standardized universal method for their identification and characterization, which limits their clinical application. This study, following the recommendations and methodologies proposed by MISEV2023 for the characterization of EVs, shows for the first time a detailed morphological, protein, and biochemical comparison between EVs derived from three different MSCs sources (placenta, endometrium, and dental pulp). The information obtained from the different applied assays suggests that there are substantial differences between one EVs source and another. It also offers valuable insights that provide the guidelines to ease their profiling and therefore improve their selection, in order to speed up their use and clinical application; additionally, the knowledge obtained from each characterization test could facilitate new researchers in the field to choose a specific cell source to obtain EVs and select the appropriate methods that provide the necessary information according to their requirements.

Biosynthesized silver nanoparticles (AgNPs) are widely used in varied applications, which are morphology dependent. Consequently, a morphology-controlled synthesis is mandatory. Although there are several studies focused on the plant extract-based biosynthesis of metallic nanoparticles, the use of extracts obtained from agro-wastes is scant. Furthermore, information regarding morphology modification through the use of additional agents is even more scarce. Thus, in this study, AgNPs were synthesized using a malt extract (ME) obtained from an artisanal beer brewing process residue. Additionally, sodium chloride (NaCl), gum arabic (GA), and talc (T) were used in an attempt to modify the morphology of AgNPs. XRD, DLS, SEM, and TEM results demonstrate that stable AgNPs of different sizes and shapes were synthesized. FTIR, HPLC analysis, and the quantification of total proteins, free amino acids, reducing sugars, and total polyphenols before and after AgNPs synthesis showed that ME biomolecules allowed them to act as a source of reducing and stabilizing agents. Therefore, this study provides evidence that ME can be successfully used to biosynthesize AgNPs. Additionally, the antibacterial activity of AgNPs against Gram-negative and Gram-positive bacteria was evaluated. Results indicate that AgNPs show a higher antibacterial activity against Gram-positive bacteria.

There is little scientific evidence for many of the medical benefits attributed to aromatherapy and neurocosmetics; however, they have been shown to be useful in the management of symptoms such as pain, nausea, general well-being, anxiety, depression, stress, and insomnia through various mechanisms, including the olfactory pathway and activation of TRPV and CBD receptors. This review therefore aims to compile the most relevant literature on active ingredients proven effective in neurocosmetics and aromatherapy, as well as the mechanisms responsible for their function, in order to highlight how they can be synergistically integrated into a new generation of multifunctional formulations forming the basis of neuro-functional skin care.

This work reports the biosynthesis of silver nanoparticles (AgNPs) using an autoclave method with Tagetes erecta extract (TEE) as a source of reducing agents, silver nitrate (AgNO₃) as the metal precursor, and a nucleating agent (i.e., sodium chloride [S]) or a structure director agent (i.e., gum Arabic [G] or hydrous magnesium silicate/talc powder [T]) to tailor the morphology of AgNPs. Since the properties and potential applications of AgNPs depend on their size and shape, these additives were employed to achieve morphological control. Phytochemical screening tests and UPCL-Qtof-MS/MS profiling of TEE were performed to identify the compounds present in the extract, indicating that highly polar phenolic compounds such as saponins, tannins, and flavonoids are present in TEE, allowing it to act as a source of reducing/stabilizing agents. The biosynthesized AgNPs exhibited different morphologies (i.e., spheres, rods, ribbons, and wires) depending on the modifying agent used (i.e., S, G, or T). Characterization techniques including scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet–visible spectroscopy (UV–vis), and X-ray diffraction (XRD) confirmed the successful use of S, G, and T in modulating AgNP morphology. The results of the antibacterial activity evaluation demonstrated that both TEE and AgNPs possess bacteriostatic activity against Escherichia coli and Enterococcus faecalis, with the use of S as a nucleating agent increasing the inhibitory effect of AgNPs.