This paper comprehensively reviews whey, a by-product of cheese production, as a raw material for various biotechnological applications. It addresses its unique composition, the environmental impact of its inadequate disposal, and the opportunities it offers to develop high-value products in line with circular economy and sustainability principles. Using the PRISMA methodology, a systematic search was conducted in various databases (Science Direct, Scopus, and Google Scholar) with specific inclusion and exclusion criteria. Studies from the last five years were considered, focusing on food applications, the production of bioproducts (such as lactic acid, biopolymers, bioethanol, biomass, and enzymes), and the use of whey as a culture medium for the expression of recombinant proteins. It is concluded that the use of whey in biotechnological applications mitigates the environmental impact associated with its disposal and represents an economic and sustainable alternative for the industrial production of bioproducts. The integration of pretreatment technologies, experimental designs, and improvements in producing strains brings these processes closer to competitive conditions in the industry, opening new perspectives for innovation in the fermentation sector.

Gibberellic acid (GA₃) is a tetracyclic diterpenoid carboxylic acid synthesized by the secondary metabolism of Fusarium fujikuroi. This phytohormone is widely studied due to the advantages it offers as a plant growth regulator, such as growth stimulation, senescence delay, flowering induction, increased fruit size, and defense against abiotic or biotic stress, which improve the quality and yield of crops. Therefore, GA₃ has been considered as an innovative strategy to improve agricultural production. However, the yields obtained at large scale are insufficient for the current market demand. This low productivity is attributed to the lack of adequate parameters to optimize the fermentation process, as well as the complexity of its regulation. Therefore, this article describes the latest advances for potentializing the GA₃ production process, including an analysis of its origins from crops, the benefits of its application, the related biosynthetic metabolism, the maximum yields achieved from production processes, and their association with genetic engineering techniques for GA₃ producers. This work provides a new perspective on the critical points of the production process, in order to overcome the limits surrounding this modern line of bioengineering.

After the first visible photoluminescence (PL) from porous silicon (pSi), continuous efforts are made to fabricate Si‐based compound nanomaterials embedded in matrices such as oxide, nitride, and carbide to improve optical performance and industrial acceptability. These nanomaterials’ functional and desired properties (nanoparticles and quantum dots embedded in matrices) can vary significantly when embedded in technologically relevant matrices. However, exploring the exact emission mechanisms is one of the remaining challenges from the past few decades. To cover this gap, this review discusses the morphological and optoelectronic properties of Si‐based compound nanomaterials and their correlation with the quantum confinement effect and different surface states to find precise emission mechanisms. One of the biggest challenges of using silicon nanomaterials in the biological sector is the development of sensitive materials of low/acceptable toxicity for identifying target analytes either inside/outside the biological platforms. In this scenario, silicon‐based compound matrices can offer different characteristics and advantages depending on their size configurations and PL emission mechanisms. On the other hand, a proper understanding of these multifaceted silicon nanomaterials’ optical properties (emission mechanisms) can be exploited for pathogen detection and in situ applications in cells and tissues, embarking on a new era of bioimaging technology.

Anxiety and depression disorders are highly prevalent neurological disorders (NDs) that impact up to one in three individuals during their lifetime. Addressing these disorders requires reducing their frequency and impact, understanding molecular causes, implementing prevention strategies, and improving treatments. Cyclic nucleotide monophosphates (cNMPs) like cyclic adenosine monophosphate (cAMP), cyclic guanosine monophosphate (cGMP), cyclic uridine monophosphate (cUMP), and cyclic cytidine monophosphate (cCMP) regulate the transcription of genes involved in neurotransmitters and neurological functions. Evidence suggests that cNMP pathways, including cAMP/cGMP, cAMP response element binding protein (CREB), and Protein kinase A (PKA), play a role in the physiopathology of anxiety and depression disorders. Plant and mushroom-based compounds have been used in traditional and modern medicine due to their beneficial properties. Bioactive compound metabolism can activate key pathways and yield pharmacological outcomes. This review focuses on the molecular mechanisms of bioactive compounds from plants and mushrooms in modulating cNMP pathways. Understanding these processes will support current treatments and aid in the development of novel approaches to reduce the prevalence of anxiety and depression disorders, contributing to improved outcomes and the prevention of associated complications. Graphical abstract

The unprecedented SARS-CoV-2 pandemic has opened huge opportunities for nanomaterial-based biosensors focused on timely detection of emerging respiratory viruses, where challenges must address actions for fast response and massive application. Accordingly, we provide a comprehensive perspective on critical aspects, including nanomaterials, biofunctionalization strategies, and bioreceptors engineering to increase accuracy, emphasizing optical nanobiosensors. The first biosensing prototype performance reveals the need to consider crucial factors for improvement, such as handling detection in complex matrices, standardization for commercial purposes, portability, integration with artificial intelligence, sustainability, and economic feasibility. By achieving these goals, biosensors would foster a prepared global healthcare landscape.