Critical Reviews in Biotechnology最新文献

Fungal diseases threaten the forest ecosystem, impacting tree health, productivity, and biodiversity. Conventional approaches to combating diseases, such as biological control or fungicides, often reach limits regarding efficacy, resistance, non-target organisms, and environmental impact, enforcing alternative approaches. From an environmental and ecological standpoint, an RNA interference (RNAi) mediated double-stranded RNA (dsRNA)-based strategy can effectively manage forest fungal pathogens. The RNAi approach explicitly targets and suppresses gene expression through a conserved regulatory mechanism. Recently, it has evolved to be an effective tool in combating fungal diseases and promoting sustainable forest management approaches. RNAi bio-fungicides provide efficient and eco-friendly disease control alternatives using species-specific gene targeting, minimizing the off-target effects. With accessible data on fungal disease outbreaks, genomic resources, and effective delivery systems, RNAi-based biofungicides can be a promising tool for managing fungal pathogens in forests. However, concerns regarding the environmental fate of RNAi molecules and their potential impact on non-target organisms require an extensive investigation on a case-to-case basis. The current review critically evaluates the feasibility of RNAi bio-fungicides against forest pathogens by delving into the accessible delivery methods, environmental persistence, regulatory aspects, cost-effectiveness, community acceptance, and plausible future of RNAi-based forest protection products.

Recently, bioactive peptides, from natural resources, have attracted remarkable attention as nutraceutical treasures and the health benefits of their consumption have extensively been studied. Therapies based on bioactive peptides have been recognized as an innovative and promising alternative method for dangerous diseases such as cancer. Indeed, there has been enormous interest in nutraceuticals and bioactive-based chemopreventive molecules as a potential opportunity to manage chronic diseases, including cancer at different stages, rather than the traditionally used therapies. The relative safety and efficacy of these peptides in targeting only the tumor cells without affecting the normal cells make them attractive alternatives to existing pharmaceuticals for the treatment, management, and prevention of cancer, being able to act as potential physiological modulators of metabolism during their intestinal digestion. Novel bioactive peptides derived from food sources can be beneficial as anticancer nutraceuticals and provide a basis for the pharmaceutical development of food-derived bioactive peptides. Bioactive peptides can be generated through different protein hydrolysis methods and purified using advanced chromatographic techniques. Moreover, establishing bioactive peptides' efficacy and mechanism of action can provide alternative methods for cancer prevention and management. Most of the research on anticancer peptides is carried out on cell lines with very limited research being investigated in animal models or human clinical models. In this context, this review article comprehensively discusses anticancer peptides': production, isolation, therapeutic strategies, mechanism of action, and application in cancer therapy.

Muconic acid (MA) is a valuable dicarboxylic acid with three isomers that are extensively utilized in textile and chemical industries. Traditionally, the chemical synthesis of MA consumes nonrenewable petrochemical raw materials and causes significant environmental problems. With the rapid increase in demand for MA, eco-friendly biosynthetic technologies with renewable sources are becoming ideal alternative solutions. This paper systematically reviews recent advances in the biosynthesis of MA isomers, describing not only the mechanism for MA biosynthesis in different microorganisms, including wild and engineered strains, but also focuses on MA production from various renewable resources, especially lignin hydrolysate and lignin-derived aromatics hydrocarbons, such as: benzoic acid, isoeugenol, vanillic acid and phenol. Moreover, cis,cis-muconic acid production from xylose, PET, methane, and glycerol are discussed in detail, providing a much broader substrate spectra and further possibilities for MA large scale industrialization economically. Challenges facing biosynthesis of cis, trans muconic acid and trans, trans muconic acid are discussed finally.

An increasing trend toward harnessing nutraceuticals as food supplements rather than pharmaceuticals as curative and preventive agents against various ailments has been observed. Owing to their health benefits, prebiotics have received notable attention from the pharmaceutical and food industries. Among the different prebiotic oligosaccharides, xylooligosaccharides (XOS) exhibited a remarkable capacity to stimulate the growth of the gut microbiota and benefit individuals with metabolic abnormalities. Additionally, XOS can be produced from various renewable agricultural wastes, which supports their economic feasibility for use as prebiotics at the industrial level. This review explains gut microbiome modulation based on in vivo, in vitro, and clinical findings. Gut microbiome modulation leads to the production of postbiotics that stimulate various beneficial health effects. The current review entails the mechanisms of different health-promoting activities mediated by XOS, including immunomodulation and anticancer effects. Additionally, the concept of converting prebiotics to synbiotics using XOS has been established for nutraceutical applications. Synbiotics based on XOS and probiotics may be good alternatives to nutraceuticals for improving human health.

G-quadruplex structures (GQSes) are the intricate molecular knots or marvels that play diverse roles in various cellular processes, such as replication, transcription, and translation, which regulate gene expression. Even though GQSes can be found throughout the genome, they are more prevalent in certain genomic regions like promoters and 5'-UTRs. This review discusses the functionality of GQSes across various regions of the genome and draws attention to the intriguing world of DNA and RNA GQSes. We highlight the uniqueness and similarities of GQSes in DNA and RNA. The functional roles of various proteins that interact with GQSes are also discussed. In addition, the role of GQSes in the context of plant development has been elaborated. The approaches for detecting GQSes using different methods and their influence in regulating gene regulation are also described. We provide insights into how GQSes can be used as potential game changers in plant biotechnology by utilizing them as regulatory switches to control various aspects of transcriptional and post-transcriptional processes depending on the arrangement of GQSes.

Gluconobacter oxydans have been widely used in industrial compound production for their incomplete oxidation ability. However, they are often subjected to a wide variety of severe environmental stresses, such as extreme pH, high temperature, osmotic pressure, and organic solvents, which greatly repress microbial growth viability and productivity. As typical biocatalysis chassis cells with a high tolerance to external environmental stresses, it is extremely important to construct highly tolerant chassis cells and understand the tolerance mechanisms of G. oxydans and how different stresses interact with the cell: membranes, phospholipid bilayers, transporters, and chaperone proteins. In this review, we discuss and summarize the mechanisms of environmental stress tolerance in G. oxydans, and the promising strategies that can be used to further construct tolerant strains are prospected.

Nicotinamide mononucleotide (NMN) presents significant therapeutic potential against aging-related conditions, such as Alzheimer's disease, due to its consistent and strong pharmacological effects. Aside from its anti-aging effect, NMN is also an emerging noncanonical cofactor for orthogonal metabolic pathways in the field of biomanufacturing. This has significant advantages in the field of metabolic engineering, allowing cells to produce unnatural chemicals without disrupting the natural cellular processes. NMN is produced through both the chemical and biological methods, with the latter being more environmentally sustainable. The primary biological production pathway centers on the enzyme nicotinamide phosphoribosyltransferase, which transforms nicotinamide and phosphoribosyl pyrophosphate to NMN. Efforts to increase NMN production have been explored in microorganisms, such as: Escherichia coli, Bacillus subtilis, and yeast, serving as biocatalysts, by rewiring their metabolic processes. Although most researchers are focusing on genetically and metabolically manipulating microorganisms to act as biocatalysts, a growing number of studies on cell-free synthesis are emerging as a promising strategy for producing NMN. This review explores the different biological production techniques of NMN employing microorganisms. This article, in particular, is essential to those who are working on NMN production using microbial strain engineering and cell-free systems.

CRISPR-based diagnostics (CRISPR/Dx) have revolutionized the field of molecular diagnostics. It enables home self-test, field-deployable, and point-of-care testing (POCT). Despite the great potential of CRISPR/Dx in diagnoses of biologically complex diseases, preamplification of the template often is required for the sensitive detection of low-abundance nucleic acids. Various amplification-free CRISPR/Dx systems were recently developed to enhance signal detection at sufficient sensitivity. Broadly, these amplification-free CRISPR/Dx systems are classified into five groups depending on the signal enhancement strategies employed: CRISPR/Cas12a and/or CRISPR/Cas13a are integrated with: (1) other catalytic enzymes (Cas14a, Csm6, Argonaute, duplex-specific nuclease, nanozyme, or T7 exonuclease), (2) rational-designed oligonucleotides (multivalent aptamer, tetrahedral DNA framework, RNA G-quadruplexes, DNA roller machine, switchable-caged guide RNA, hybrid locked RNA/DNA probe, hybridized cascade probe, or "U" rich stem-loop RNA), (3) nanomaterials (nanophotonic structure, gold nanoparticle, micromotor, or microbeads), (4) electrochemical and piezoelectric plate biosensors (SERS nanoprobes, graphene field-effect transistor, redox probe, or primer exchange reaction), or (5) cutting-edge detection technology platforms (digital bioanalysis, droplet microfluidic, smartphone camera, or single nanoparticle counting). Herein, we critically discuss the advances, pitfalls and future perspectives for these amplification-free CRISPR/Dx systems in nucleic acids detection. The continued refinement of these CRISPR/Dx systems will pave the road for rapid, cost-effective, ultrasensitive, and ultraspecific on-site detection without resorting to target amplification, with the ultimate goal of establishing CRISPR/Dx as the paragon of diagnostics.

The development and commercialization of bio-based and biodegradable polyhydroxyalkanoates (PHAs) biopolymers could be crucial for the transition toward a sustainable circular economy. However, despite potential traditional and novel applications in the packaging, textiles, agriculture, automotive, electronics, and biomedical industries, the commercialization of PHAs is limited by their current market competitiveness. This review provides the first critical assessment of the current pure culture pilot-scale PHA literature, which could be crucial in translating promising laboratory-scale developments into industrial-scale commercial PHA production. It will also complement reviews of mixed microbial cultures currently dominating pilot-scale PHA literature. Pure culture fermentations could provide advantages, such as ease of characterizing microbial producers' behavior, higher PHA productivities, and better alignment with existing PHA commercialization and industrial biotechnology approaches. Key aspects, including producer organisms, fermentation volumes and schemes, control schemes, optimization, and properties of the polymers produced, are discussed in-depth, to elucidate important trends, achievements, and knowledge gaps. Furthermore, specific ways for future pilot-scale studies to help address current PHA commercialization challenges are also identified. The insights, and recommendations provided will be extremely beneficial for the future development of PHA production, at both pilot and commercial scales, whilst also being beneficial to the production of other microbial polymers and industrial biotechnology as a whole.

Vibrational spectroscopy is a nondestructive analysis technique that depends on the periodic variations in dipole moments and polarizabilities resulting from the molecular vibrations of molecules/atoms. These methods have important advantages over conventional analytical techniques, including (a) their simplicity in terms of implementation and operation, (b) their adaptability to on-line and on-farm applications, (c) making measurement in a few minutes, and (d) the absence of dangerous solvents throughout sample preparation or measurement. Food safety is a concept that requires the assurance that food is free from any physical, chemical, or biological hazards at all stages, from farm to fork. Continuous monitoring should be provided in order to guarantee the safety of the food. Regarding their advantages, vibrational spectroscopic methods, such as Fourier-transform infrared (FTIR), near-infrared (NIR), and Raman spectroscopy, are considered reliable and rapid techniques to track food safety- and food authenticity-related issues throughout the food chain. Furthermore, coupling spectral data with chemometric approaches also enables the discrimination of samples with different kinds of food safety-related hazards. This review deals with the recent application of vibrational spectroscopic techniques to monitor various hazards related to various foods, including crops, fruits, vegetables, milk, dairy products, meat, seafood, and poultry, throughout harvesting, transportation, processing, distribution, and storage.