Search

Over the past five years, there has been growing interest in the design of modified cellulose nanocrystals (CNCs) as nanoscale antimicrobial agents in potential end-user applications such as food preservation/packaging, additive manufacturing, biomedical and water purification. The interest of applying CNCs-based antimicrobial agents arise due to their abilities to be derived from renewable bioresources and their excellent physicochemical properties including rod-like morphologies, large specific surface area, low toxicity, biocompatibility, biodegradability and sustainability. The presence of ample surface hydroxyl groups further allows easy chemical surface modifications for the design of advanced functional CNCs-based antimicrobial materials. Furthermore, CNCs are used to support antimicrobial agents that are subjected to instability issues. The current review summarizes recent progress in CNC-inorganic hybrid-based materials (Ag and Zn nanoparticles, other metal/metal oxide) and CNC-organic hybrid-based materials (polymers, chitosan, simple organic molecules). It focuses on their design, syntheses and applications with a brief discussion on their probable modes of antimicrobial action whereby the roles of CNCs and/or the antimicrobial agents are highlighted. [Display omitted] [ABSTRACT FROM AUTHOR]

The article focuses on the immobilization of antibodies and enzymes on aminopropyltriethoxysilane (APTES)-functionalized bioanalytical platforms for biosensing and diagnostic devices. It discusses the role of immobilization strategies and their impact on sensitivity, detection limit and operational and storage stability. It further reflects on the advantages of APTES biosensors in analytical applications including easy preparation, stable monolayers and uniform immobilization surface.

In recent years, cellulose nanocrystals (CNCs) have emerged as a leading biomass-based nanomaterial owing to their unique functional properties and sustainable resourcing. Sulfated cellulose nanocrystals (sCNCs), produced by sulfuric acid-assisted hydrolysis of cellulose, is currently the predominant form of this class of nanomaterial; its utilization leads the way in terms of CNC commercialization activities and industrial applications. The functional properties, including high crystallinity, colloidal stability, and uniform nanoscale dimensions, can also be attained through carboxylated cellulose nanocrystals (cCNCs). Herein, we review recent progress in methods and feedstock materials for producing cCNCs, describe their functional properties, and discuss the initial successes in their applications. Comparisons are made to sCNCs to highlight some of the inherent advantages that cCNCs may possess in similar applications. [ABSTRACT FROM AUTHOR]

Chitosan is readily available from various biomass waste streams including crustaceans, cephalopods, insects, and fungus. The polymer possesses primary amine groups which are great handles for functionalization. Yet efficient functionalization with high degree of substitution is challenging to achieve via solvothermal methods due to limitations in chitosan solvation properties. Herein we report a mechanochemical and aging-based method directly addressing this point. Working in the solid phase helps stabilize the formation of Schiff bases from chitosan and aldehydes, affording a novel pathway to the green functionalization of chitosan by reductive alkylation, with unprecedentedly high degrees of substitution. The method showed great efficacy and compatibility for chitosan to be functionalized with 21 different aldehyde substrates and a low process mass intensity (PMI) of 36. This work also opens a new avenue for the development of mechanochemical and aging-based reductive amination transformations. [ABSTRACT FROM AUTHOR]

Single-cell protein (SCP) is an evolving biotechnological concept that can potentially align protein production with the global sustainability commitment. This review presents an overview of SCP's current outlook, including production, commercial prospects, and sustainability status. It also elaborates on the potential of the evolving digital twin concept in improving SCP production's efficiency and sustainability performance. An expanding body of work was identified, with well-explored fermentative approaches and varying substrates and microbes. Whereas interest in first-generation substrates such as methane is gradually fading due to their high competitiveness and acquisition cost, second-generation substrates such as lignocellulosic materials and agro-industrial wastes are rapidly evolving due to their availability, low cost, appreciable nutrient density, and alignment with the circular bioeconomy path. Sustainability assessment of current production attaches substantial environmental, mainly global warming and land use offset, and economic savings to SCP production. Moreover, it emphasizes conventional energy use as a hotspot contributor to all impact categories. However, research on life cycle costing, social life cycle assessment, and environmental nutrition concepts is limited. Current trends project rapid market growth for SCP due to expanding feed, food, and nonfood applications. The rapid influx of transformative innovations such as mixed culture biotechnology and the emerging digital twin concept that present catalytic advantages in achieving market growth and sustainability cobenefits are backing these projections. Several sensor and predictive technologies are available to enable an SCP-digital twin path, presenting an opportunity to enhance green and precision SCP production. Despite these innovations, significant efforts are required to overcome limitations concerning toxicity, legislative restrictions, technical constraints, and consumer neophobia to bolster commerce and market value. [Display omitted] • Agro-industrial waste upcycling should frontline circular bioeconomy actions for value recovery. • Single Cell Protein production can align protein supply with global sustainability commitment. • Closing sustainability loop in pulse protein extraction with single cell protein pathway. • Combine environment, economic, social, and nutrition metrics in single cell protein assessment. • Adopt digital twin to for better control and optimization of single cell protein production. [ABSTRACT FROM AUTHOR]

• %Amylose of pea flours had a good correlation with %starch (r = -0.990, p < 0.001). • %Amylose showed positive correlations with %protein and %dietary fiber (p < 0.001). • A higher amylose content increased starch gelatinization temp. of pea flours. • Pea flours with more amylose needed higher heating temp. to give viscosity and gel. • %Amylose increased %resistant starch but did not influence protein digestibility. In this study, ten pea flours covering a broad range of amylose content (37.2–77.6 %, dsb) were characterized for functional and nutritional properties. As the amylose contents increased, the starch contents of the pea flours showed a downward trend (r = -0.990, p < 0.001 in Pearson correlation) but their protein and total dietary fiber contents exhibited an upward trend (r = 0.915, p < 0.001 and r = 0.885, p < 0.001, respectively). A greater amylose content tended to increase starch gelatinization temperatures of the pea flours, which thus required a higher cooking temperature for pasting viscosity development and subsequent gel formation. An increased amylose level reduced in vitro starch digestibility of the cooked pea flours (r = -0.944, p < 0.001) but did not influence in vitro protein digestibility. The insightful findings will be valuable for utilizing the diverse pea lines to create new flour, starch, and protein ingredients. [ABSTRACT FROM AUTHOR]

The world is currently facing a global health crisis due to the rapid increase in antimicrobial-resistant bacterial infections. One of the most concerning pathogens is Acinetobacter baumannii, which is listed as a Priority 1 pathogen by the World Health Organization. This Gram-negative bacterium has many intrinsic antibiotic resistance mechanisms and the ability to quickly acquire new resistance determinants from its environment. A limited number of effective antibiotics against this pathogen complicates the treatment of A. baumannii infections. A potential treatment option that is rapidly gaining interest is "phage therapy", or the clinical application of bacteriophages to selectively kill bacteria. The myoviruses DLP1 and DLP2 (vB_AbaM-DLP_1 and vB_AbaM-DLP_2, respectively) were isolated from sewage samples using a capsule minus variant of A. baumannii strain AB5075. Host range analysis of these phages against 107 A. baumannii strains shows a limited host range, infecting 15 and 21 for phages DLP1 and DLP2, respectively. Phage DLP1 has a large burst size of 239 PFU/cell, a latency period of 20 min, and virulence index of 0.93. In contrast, DLP2 has a smaller burst size of 24 PFU/cell, a latency period of 20 min, and virulence index of 0.86. Both phages show potential for use as therapeutics to combat A. baumannii infections. [ABSTRACT FROM AUTHOR]

Cationic nanomaterials are promising candidates for the development of effective antibacterial agents by taking advantage of the nanoscale effects as well as other exceptional physicochemical properties of nanomaterials. In this study, carboxylated cellulose nanocrystals (cCNCs) derived from softwood pulp were coated with cationic poly(diallyldimethylammonium chloride) of varying molecular weights. The resulting cationic carboxylated cellulose nanocrystals coated with poly(diallyldimethylammonium chloride) (cCNCs–PDDA) nanomaterials were characterized for their structural and morphological properties using Fourier transform infrared spectroscopy, dynamic light scattering, zeta potential, elemental analysis, transmission electron microscopy, and thermogravimetric analysis. Cationic cCNCs–PDDA were investigated for their antibacterial properties against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli 23934 and Pseudomonas aeruginosa using a bacterial lawn growth inhibition assay. cCNC–PDDA materials displayed marked antibacterial activity, particularly against Gram-positive Staphylococcus aureus. Overall, our results indicated that cCNCs–PDDA could be a potential candidate for antibacterial applications such as antibacterial surfaces or coatings. [ABSTRACT FROM AUTHOR]

The consumer demand for starch continues to grow to meet food consumption needs. However, starch producers are increasingly looking towards non-food, industrial applications to access new markets for revenue generation, while aiming for whole crop utilization to meet sustainability metrics. Native starch properties limit its utilization in many industrial applications, therefore, it is modified through different chemical, enzymatic, and physical processes. This review examines innovation in starch transformation processes, and how modified starch and its functional properties can be used in industrial applications beyond the traditional sectors of textiles and papermaking. Currently, the market value of modified starch is 2.7× greater than native starch and is anticipated to increase through next-generation applications (e.g. packaging, energy and regenerative medicine) enabled by emerging technologies in 3D printing and nanotechnology. Opportunities for increasing the use of other botanical starch sources besides industry-leading corn are also presented through the lens of global market trends. [Display omitted] • Non-food, industrial applications are identified as a means for starch producers to access new markets for revenue generation. • The utility of native starch is limited in most industrial applications. • The current market value for modified starch is 2.7× greater than native starch. • Recent advances in chemical, enzymatic, and physical modification of starch are presented. • Traditional and next-generation industrial applications are assessed based on research innovation and global market trends. [ABSTRACT FROM AUTHOR]

To unlock nature's potential for functional biomaterials, many efforts have been devoted to isolating the nanocrystalline domains within the supramolecular structure of polysaccharides. Yet, low reactivity and yield in aqueous systems along with excessive solvent usage hinders its development. In this report, the first solvent‐free pathway to access carboxylated chitin and cellulose nanocrystals with excellent mass balance is described, relying on a new method coined high‐humidity shaker aging (HHSA). The method involves a mild grinding of the polysaccharide with ammonium persulfate followed by an aging phase under high‐humidity and on a shaker plate. Insights into the mechanism were uncovered, which highlighted the unique role of high humidity to afford a gradual uptake of water by the material up to deliquescence when the reaction is complete. This process was then validated for direct synthesis of nanocrystals from biomass sources including crab and soft wood pulp. [ABSTRACT FROM AUTHOR]

To unlock nature's potential for functional biomaterials, many efforts have been devoted to isolating the nanocrystalline domains within the supramolecular structure of polysaccharides. Yet, low reactivity and yield in aqueous systems along with excessive solvent usage hinders its development. In this report, the first solvent‐free pathway to access carboxylated chitin and cellulose nanocrystals with excellent mass balance is described, relying on a new method coined high‐humidity shaker aging (HHSA). The method involves a mild grinding of the polysaccharide with ammonium persulfate followed by an aging phase under high‐humidity and on a shaker plate. Insights into the mechanism were uncovered, which highlighted the unique role of high humidity to afford a gradual uptake of water by the material up to deliquescence when the reaction is complete. This process was then validated for direct synthesis of nanocrystals from biomass sources including crab and soft wood pulp. [ABSTRACT FROM AUTHOR]

Tough bioadhesion has important implications in engineering and medicine but remains challenging to form and control. We report an ultrasound (US)-mediated strategy to achieve tough bioadhesion with controllability and fatigue resistance. Without chemical reaction, the US can amplify the adhesion energy and interfacial fatigue threshold between hydrogels and porcine skin by up to 100 and 10 times. Combined experiments and theoretical modeling suggest that the key mechanism is US-induced cavitation, which propels and immobilizes anchoring primers into tissues with mitigated barrier effects. Our strategy achieves spatial patterning of tough bioadhesion, on-demand detachment, and transdermal drug delivery. This work expands the material repertoire for tough bioadhesion and enables bioadhesive technologies with high-level controllability. [ABSTRACT FROM AUTHOR]

The huge worldwide demand for vaccines targeting SARS-CoV-2 has necessitated the continued development of novel improved formulations capable of reducing the burden of the COVID-19 pandemic. Herein, we evaluated novel protein subunit vaccine formulations containing a resistin-trimerized spike antigen, SmT1. When combined with sulfated lactosyl archaeol (SLA) archaeosome adjuvant, formulations induced robust antigen-specific humoral and cellular immune responses in mice. Antibodies had strong neutralizing activity, preventing viral spike binding and viral infection. In addition, the formulations were highly efficacious in a hamster challenge model reducing viral load and body weight loss even after a single vaccination. The antigen-specific antibodies generated by our vaccine formulations had stronger neutralizing activity than human convalescent plasma, neutralizing the spike proteins of the B.1.1.7 and B.1.351 variants of concern. As such, our SmT1 antigen along with SLA archaeosome adjuvant comprise a promising platform for the development of efficacious protein subunit vaccine formulations for SARS-CoV-2. [ABSTRACT FROM AUTHOR]

Marine biomass waste is a remarkable source of functional molecules and materials. Yet material extraction, conversion and processing are often chemically intensive, preventing the widespread and clean use of these abundant resources for high-end applications. Moreover, current challenges in biomedicine call for the design of novel materials with better functional and mechanical properties. Herein, we present a novel chemical process to afford chitosan nanocrystals (ChsNCs), which uniquely combine a high degree of deacetylation, rod shape and high crystallinity for mechanical robustness. This method is a simple solid-state aging process starting from chitin nanocrystals (ChNCs) and requiring limited chemical and energetic input, which we have quantified using process mass intensity as the sustainability metric. This method, as well as a previously reported solution-based method, afforded a family of novel nanomaterials, which we used to form alginate hydrogels. The resulting materials are the first examples of ChsNC-based hydrogels and featured superior performances in terms of both rheological properties, as well as sustained drug release, as compared to previously reported chitosan/alginate systems. This work opens an avenue for functional soft materials using a green resource via a clean process. [ABSTRACT FROM AUTHOR]

Globally, the demand for protein continues to exceed its supply due to the geometric increase in population. For sustainability reasons, the high demand is leading to a shift in interest from animal-based protein, towards consuming high plant protein, sourced mainly from legumes and pulses. Traditional methods for protein extraction have been deployed to ensure availability and convenient utilization of these novel protein sources. Dry and wet fractionation are the two main categories of traditional protein extraction methods, with dry fractionation being more sustainable and frequently used. However, the repercussions trailing these methods keep encouraging research towards greener extraction pathways to ensure more protein availability and sustainability. The key drivers of this transition are increased yield, quality, uniformity and process eco-friendliness. Microwave, ultrasonic energy, pulse electric field, hydrodynamic cavitation extraction and tribo-electrostatic separation, among other novel technologies, appear to be the most likely techniques to dominate in the next few decades. This prospection hinges on available data of their performance efficiency in pulse / legume protein extraction and observed relatively higher yield potentials, protein quality, demand for less water, solvents and energy. The latter inarguably favors the food-energy-water nexus and could contribute considerably to environmental sustainability. Nonetheless, available knowledge cannot suffice effective and sustainable deployments of these techniques in legume protein extraction. Therefore, the gap on process performance and possible optimization of process parameters of these novel technologies deserves urgent attention. The product-process efficiency is highly critical for better understanding of the chances for process scale-up. This has been identified as the present stage of research in this domain. [Display omitted] • Pulses and legumes play essential roles in tackling food security problems globally. • Conventional legume protein extraction methods impact negatively on the environment. • Paucity of studies on green technologies in protein extraction limit their scale up. • With Green technologies, water-food-energy nexus future projection is achievable. • Ultrasound and dry fractionation offer desirable trade off to sustainability. [ABSTRACT FROM AUTHOR]

Protein extraction from pulses has received significant attention in the food processing industry, and as such, several studies have been conducted to develop new methods and to improve upon the conventional methods. In all these, a broad data synthesis to pool and analyze data from these studies to assess and understand the status quo of the pulse-protein extraction technologies, is still wanting. Therefore, there is the need to synthesize data reported by the extensive collection of studies to inform stakeholders on the right pathways for development, critical understanding, and optimization purposes. A meta-analysis was conducted to assess the efficiency of three main extraction processes under two performance indicators of efficiency -protein purity and protein recovery with data points from 41 published studies. The meta-analysis showed that processing conditions affect purity and recovery levels. Several investigations are still to be conducted to understand critical aspects of the pulse extraction processes. Challenges and hotspots requiring further research for a better understanding of some aspects of the extraction process are also presented. • Meta analysis of pulse protein extraction and its impacts on purity and recovery is conducted. • No significant observable difference in protein purity and recovery exists among different pulses. • Thorough studies on effect of voltage on the protein purity is required for the electrostatic separation method. • There are trade-offs between purity and recovery as values of processing conditions increase or decrease. • Hybrid fractionation, the more sustainable and efficient pathway, has been exploited the least. [ABSTRACT FROM AUTHOR]

Cancer remains a leading cause of morbidity and mortality worldwide. While novel treatments have improved survival outcomes for some patients, new treatment modalities/platforms are needed to combat a wider variety of tumor types. Cancer vaccines harness the power of the immune system to generate targeted tumor-specific immune responses. Liposomes composed of glycolipids derived from archaea (i.e., archaeosomes) have been shown to be potent adjuvants, inducing robust, long-lasting humoral and cell-mediated immune responses to a variety of antigens. Herein, we evaluated the ability of archaeosomes composed of sulfated lactosyl archaeol (SLA), a semi-synthetic archaeal glycolipid, to enhance the immunogenicity of a synthetic long peptide-based vaccine formulation containing the dominant CD8+ T cell epitope, SIINFEKL, from the weakly immunogenic model antigen ovalbumin. One advantage of immunizing with long peptides is the ability to include multiple epitopes, for example, the long peptide antigen was also designed to include the immediately adjacent CD4+ epitope, TEWTSSNVMEER. SLA archaeosomes were tested alone or in combination with the toll-like receptor 3 (TLR3) agonist Poly(I:C). Overall, SLA archaeosomes synergized strongly with Poly(I:C) to induce robust antigen-specific CD8+ T cell responses, which were highly functional in an in vivo cytolytic assay. Furthermore, immunization with this vaccine formulation suppressed tumor growth and extended mouse survival in a mouse melanoma tumor model. Overall, the combination of SLA archaeosomes and Poly(I:C) appears to be a promising adjuvant system when used along with long peptide-based antigens targeting cancer. [ABSTRACT FROM AUTHOR]

Archaeosomes, composed of sulfated lactosyl archaeol (SLA) glycolipids, have been proven to be an effective vaccine adjuvant in multiple preclinical models of infectious disease or cancer. SLA archaeosomes are a promising adjuvant candidate due to their ability to strongly stimulate both humoral and cytotoxic immune responses when simply admixed with an antigen. In the present study, we evaluated whether the adjuvant effects of SLA archaeosomes could be further enhanced when combined with other adjuvants. SLA archaeosomes were co-administered with five different Toll-like Receptor (TLR) agonists or the saponin QS-21 using ovalbumin as a model antigen in mice. Both humoral and cellular immune responses were greatly enhanced compared to either adjuvant alone when SLA archaeosomes were combined with either the TLR3 agonist poly(I:C) or the TLR9 agonist CpG. These results were also confirmed in a separate study using Hepatitis B surface antigen (HBsAg) and support the further evaluation of these adjuvant combinations. [ABSTRACT FROM AUTHOR]