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Traditional packaging materials feed the growing global food protection. However, these packaging materials are not conducive to environment and have not the ability to kill bacteria. Herein, a green and simple strategy is reported for food packaging protection and long-term antibacterial using carboxymethylcellulose-based photothermal film (CMC@CuS NPs/PVA) that consists of carboxymethyl cellulose (CMC) immobilized copper sulfide nanoparticles (CuS NPs) and polyvinyl alcohol (PVA). With satisfied oxygen transmittance (0.03 cc/m 2 /day) and water vapor transmittance (163.3 g/m 2 /day), the tensile strength, tear strength and burst strength reached to 3401.2 N/m, 845.7 mN and 363.6 kPa, respectively, which could lift 4.5 L of water. The composite film had excellent photothermal conversion efficiency and photothermal stability. Under the irradiation of near infrared (NIR), it can rapidly heated up to 197 °C within 25 s. The antibacterial analysis showed that the inhibition rate of composite film against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) could all reach >99 %. Furthermore, the synthesized CuS NPs was well immobilized and the residual rate of copper kept 98.7 % after 10 days. Noticeably, the composite film can preserve freshness of strawberries for up to 6 days. Therefore, the composite film has potential application for food antibacterial protection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Butelase-1, the fastest known Asn/Asp-specific peptide ligase capable of catalyzing peptide ligation and cyclization, holds promising application prospects in the fields of food and biology. However, limited research exists on its recombinant expression and potential applications in peptide drugs. In this study, the activity of recombinantly-produced butelase-1 was enhanced by co-expressing it with a molecular chaperone in the SHuffle T7 strain. By introducing single or multiple synonymous rare codons at the beginning of the coding regions of beta-strand or alpha-helix, in combination with ribosomal binding site engineering, the activity of butelase-1 could be further improved. Consequently, the butelase-1 with a specific activity of 386.93 U/mg and a catalytic efficiency of 11,048 M -1  s -1 was successfully prepared in E. coli, resulting in a total activity of 8183.54 U/L and a yield of about 100 mg/L. This optimized butelase-1 was then used to efficiently cyclize the redesigned anti-cancer peptide lunasin, leading to enhanced bioavailability and anti-cancer effects. Overall, this study not only provided valuable biotechnology strategies for improving the recombinant expression of butelase-1 but also demonstrated a successful application for enhancing the biological efficacy of anti-cancer peptides., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Given the widespread prevalence of viruses, there is an escalating demand for antimicrobial composites. Although the composite of dialdehyde cellulose and silver nanoparticles (DAC@Ag1) exhibits excellent antibacterial properties, its weak mechanical characteristics hinder its practical applicability. To address this limitation, cellulose nanofibers (CNFs) were initially ammoniated to yield N-CNF, which was subsequently incorporated into DAC@Ag1 as an enhancer, forming DAC@Ag1/N-CNF. We systematically investigated the optimal amount of N-CNF and characterized the DAC@Ag1/N-CNF using FT-IR, XPS, and XRD analyses to evaluate its additional properties. Notably, the optimal mass ratio of N-CNF to DAC@Ag1 was found to be 5:5, resulting in a substantial enhancement in mechanical properties, with a 139.8% increase in tensile elongation and a 33.1% increase in strength, reaching 10% and 125.24 MPa, respectively, compared to DAC@Ag1 alone. Furthermore, the inhibition zones against Escherichia coli and Staphylococcus aureus were significantly expanded to 7.9 mm and 15.9 mm, respectively, surpassing those of DAC@Ag1 alone by 154.8% and 467.9%, indicating remarkable improvements in antimicrobial efficacy. Mechanism analysis highlighted synergistic effects from chemical covalent bonding and hydrogen bonding in the DAC@Ag1/N-CNF, enhancing the mechanical and antimicrobial properties significantly. The addition of N-CNF markedly augmented the properties of the composite film, thereby facilitating its broader application in the antimicrobial field.

Sustainable composite hydrogel materials with harsh environmental adaption and tolerance capability have received considerable interests but still remain as challenges. In this work, biomimetic strategy was adapted for construction of three-dimensional galactomannan (GM) hydrogels with intercalation of flexible polymer chains polyethyleneimine (PEI), biomacromolecules tannin acid (TA) and CeO2 nanoparticles (NPs). The hydrogels cross-linked with double-networks (DN) present not only pH-responsive water absorption property, but also boosted mechanical strength with highest toughness of 326 kJ/m 3 and Young's modulus of 220 kPa. Self-healing and anti-freezing capabilities were revealed for the hydrogels by maintaining of fracture elongation (23 %) and fracture strength (250 kPa). TA, CeO2 NPs as well as the amide groups in PEI of the hydrogels introduced excellent bacterial prohibition performance on both Bacillus subtilis (B. subtilis) and Escherichia coli (E. coli). Also, due to the existence of the free ions, the hydrogels exhibited electric conductive properties, with wide-range high sensitivity and long-time conductive stability. In addition, various tensile strain degrees were related to the conductive resistance values, and the great recovery performance was proved by cyclic tensile-conductive tests for 3000 times. Therefore, the proposed GM-based hydrogels displayed great potentials as strain sensors that are adaptable and tolerant to various environmental conditions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

As advances are made toward the industrial feasibility of mass-producing biofuels and commodity chemicals with sugar-fermenting microbes, high feedstock costs continue to inhibit commercial application. Hydrolyzed lignocellulosic biomass represents an ideal feedstock for these purposes as it is cheap and prevalent. However, many microbes, including Escherichia coli , struggle to efficiently utilize this mixture of hexose and pentose sugars due to the regulation of the carbon catabolite repression (CCR) system. CCR causes a sequential utilization of sugars, rather than simultaneous utilization, resulting in reduced carbon yield and complex process implications in fed-batch fermentation. A mutant of the gene encoding the cyclic AMP receptor protein, crp* , has been shown to disable CCR and improve the co-utilization of mixed sugar substrates. Here, we present the strain construction and characterization of a site-specific crp* chromosomal mutant in E. coli BL21 star (DE3). The crp* mutant strain demonstrates simultaneous consumption of glucose and xylose, suggesting a deregulated CCR system. The proteomics further showed that glucose was routed to the C5 carbon utilization pathways to support both de novo nucleotide synthesis and energy production in the crp* mutant strain. Metabolite analyses further show that overflow metabolism contributes to the slower growth in the crp* mutant. This highly characterized strain can be particularly beneficial for chemical production by simultaneously utilizing both C5 and C6 substrates from lignocellulosic biomass.IMPORTANCEAs the need for renewable biofuel and biochemical production processes continues to grow, there is an associated need for microbial technology capable of utilizing cheap, widely available, and renewable carbon substrates. This work details the construction and characterization of the first B-lineage Escherichia coli strain with mutated cyclic AMP receptor protein, Crp*, which deregulates the carbon catabolite repression (CCR) system and enables the co-utilization of multiple sugar sources in the growth medium. In this study, we focus our analysis on glucose and xylose utilization as these two sugars are the primary components in lignocellulosic biomass hydrolysate, a promising renewable carbon feedstock for industrial bioprocesses. This strain is valuable to the field as it enables the use of mixed sugar sources in traditional fed-batch based approaches, whereas the wild-type carbon catabolite repression system leads to biphasic growth and possible buildup of non-preferential sugars, reducing process efficiency at scale., Competing Interests: The authors declare no conflict of interest.

Graphene oxide (GO), TiO 2 -NPs, HPMC, and shellac are environmentally green polymers and nanocomposites. This work aimed to create biodegradable composite films made of HPMC/shellac, HPMC/shellac-GO, and HPMC/shellac-GO/TiO 2 -NPs by film casting. TiO 2 -HPMC/shellac-GO matrix's dispersibility and mixing ability were characterized and observed using FTIR and XRD. XRD analysis shows that the crystallinity decreased within the composites due to breaking H-bonding. Compared to HPMC/shellac, TGA/DTG demonstrated the composite films' superior thermal stability. TiO 2 (0.08-0.16 %) was cast into a composite film comprising HPMC, shellac, and GO. The homogeneity of TiO 2 distribution in the composite film was shown using a SEM, which was also used to display the morphology of nanocomposite films. Nanocomposite films' thickness, air permeability, tensile strength, Young's modulus, and burst strength were examined. The results demonstrated that natural films prepared by a combination of shellac/GO with HPMC enhanced the fabricating of films' properties, the tensile strength increased by 231 % (from 16 to 53 MPa) in HPMC and HPSG2 (HPMC 1.9 g/shellac 0.25 g/GO 0.125 g in 100 mL) respectively, whereas the contact angle did not change. And after addition of TiO 2 -NPs, there were high enhancements in HPMC films' properties, such tensile strength increased by 212 % (from 16 to 50 MPa), burst strength increased by 20.96 % (3.1 to 3.75 Kg/cm 2 ), and the contact angle by 60.86 % (48 to 74°) in HPMC and HPSGT2 respectively. Compared to HPMC films, films exhibited the highest levels of antibacterial activity against E. coli, B. mycoides, and C. albicans. So, the composite films from HPMC/shellac/GO/TiO 2 -NPs are promising potential packaging materials., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The use of polyelectrolytes is emerging as a fascinating strategy for the functionalization of biomedical membranes, due to their ability to enhance biological responses using the interaction effect of charged groups on multiple interface properties. Herein, two different polyelectrolytes were used to improve the antibacterial properties of polycaprolactone (PCL) nanofibers fabricated via electrospinning. First, a new cationic cellulose derivative, cellulose-bearing imidazolium tosylate (CIMD), was prepared via the nucleophilic substitution of the tosyl group using 1-methylimidazole, as confirmed by NMR analyses, and loaded into the PCL nanofibers. Secondly, sodium alginate (SA) was used to uniformly coat the fibers' surface via self-assembly, as remarked through SEM-EDX analyses. Polyelectrolyte interactions between the CIMD and the SA, initially detected using a FTIR analysis, were confirmed via Z potential measurements: the formation of a CMID/SA complex promoted a substantial charge neutralization of the fibers' surfaces with effects on the physical properties of the membrane in terms of water adsorption and in vitro degradation. Moreover, the presence of SA contributed to the in vitro response of human mesenchymal stem cells (hMSCs), as confirmed by a significant increase in the cells' viability after 7 days in the case of the PCL/CMID/SA complex with respect to the PCL and PCL/CMID membranes. Contrariwise, SA did not nullify the antibacterial effect of CMID, as confirmed by the comparable resistance exhibited by S. mutans , S. aureus, and E. coli to the PCL/CIMD and PCL/CIMD/SA membranes. All the reported results corroborate the idea that the CIMD/SA functionalization of PCL nanofibers has a great potential for the fabrication of efficient antimicrobial membranes for wound healing.

Mixing, homogenization, separation, and filtration are crucial processes in miniaturized analytical systems employed for in-vitro biological, environmental, and food analysis. However, in microfluidic systems achieving homogenization becomes more challenging due to the laminar flow conditions, which lack the turbulent flows typically used for mixing in traditional analytical systems. Here, we introduce an acoustofluidic platform that leverages an acoustic transducer to generate microvortex streaming, enabling effective homogenizing of food samples. To reduce reliance on external equipment, tubing, and pump, which is desirable for Point-of-Need testing, our pumpless platform employs a hydrophilic yarn capable of continuous wicking for sample perfusion. Following the homogenization process, the platform incorporates an array of micropillars for filtering out large particles from the samples. Additionally, the porous structure of the yarn provides a secondary screening mechanism. The resulting system is compact, and reliable, and was successfully applied to the detection of Escherichia coli (E. coli) in two different types of berries using quantitative polymerase chain reaction (qPCR). The platform demonstrated a detection limit of 5 CFU g -1 , showcasing its effectiveness in rapid and sensitive pathogen detection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Hypothesis: Pickering emulsions, defined as emulsions that are stabilized by colloidal particles, provide dispersion stability by preventing coalescence of the dispersed phase. In this study, we used a bifunctional hairy nanocellulose (BHNC) bearing both aldehyde and carboxylic acid groups as an stabilizer. We hypothesize that these particles as Pickering stabilizers can effectively reside at the oil-water interface, better than hairy nanocelluloses containing only carboxyl groups or aldehyde groups, and provide long-term stability without the need of any surfactants., Experiments: Varying concentrations of BHNC were tested to explore the optimal concentration that provides emulsion stability. The effects of various preparation conditions such as salt and pH were also studied. Finally, carvacrol, an antibacterial essential oil, was loaded in the oil phase to develop antibacterial emulsions., Findings: It was shown that a 1% BHNC suspension provides 90% and 80% stability for a duration of 30 and 60 days, respectively. A theoretical model using nuclear magnetic resonance relaxometry data is developed to prove that only a monolayer of BHNC covers oil droplets. Increasing the concentration of BHNC decreased the size of oil droplets, which as a result increases the surface area available for monolayer coverage. It was also shown that the antibacterial emulsions are highly effective against Gram-negative (i.e. E. coli) and Gram-positive (i.e. S. aureus) bacteria. Accordingly, BHNC as a highly functionalized bio-derived colloidal particle opens new opportunities for engineering highly stable Pickering emulsions., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Traditional psychedelics are undergoing a transformation from recreational drugs, to promising pharmaceutical drug candidates with the potential to provide an alternative treatment option for individuals struggling with mental illness. Sustainable and economic production methods are thus needed to facilitate enhanced study of these drug candidates to support future clinical efforts. Here, we expand upon current bacterial psilocybin biosynthesis by incorporating the cytochrome P450 monooxygenase, PsiH, to enable the de novo production of psilocybin as well as the biosynthesis of 13 psilocybin derivatives. The substrate promiscuity of the psilocybin biosynthesis pathway was comprehensively probed by using a library of 49 single-substituted indole derivatives, providing biophysical insights to this understudied metabolic pathway and opening the door to the in vivo biological synthesis of a library of previously unstudied pharmaceutical drug candidates., (© 2023 The Authors. Biotechnology and Bioengineering published by Wiley Periodicals LLC.)

The lignin precursors of coniferin and syringin were synthesised, and guaiacyl-type and guaiacyl-syringyl-type oligomeric lignin dehydrogenation polymers (DHP and DHP-GS) were prepared with the bulk method. The carbon-13 nuclear magnetic resonance spectroscopy showed that both DHP-G and DHP-GS contained β-O-4, β-5, β-β, β-1, and 5-5 substructures. Extraction with petroleum ether, ether, ethanol, and acetone resulted in four fractions for each of DHP-G (C 11 -C 14 ) and DHP-GS (C 21 -C 24 ). The antibacterial experiments showed that the fractions with lower molecular weight had relatively strong antibacterial activity. The ether-soluble fractions (C 12 of DHP-G and C 22 of DHP-GS) had strong antibacterial activities against E. coli and S. aureus . The C 12 and C 22 fractions were further separated by preparative chromatography, and 10 bioactive compounds (G 1 -G 5 and GS 1 -GS 5 ) were obtained. The overall antibacterial activities of these 10 compounds was stronger against E. coli than S. aureus . Compounds G 1 , G 2 , G 3 , and GS 1 , which had the most significant antibacterial activities, contained β-5 substructures. Of these, G 1 had the best antibacterial activity. Its inhibition zone diameter was 19.81 ± 0.82 mm, and the minimum inhibition concentration was 56.3 ± 6.20 μg/mL. Atmospheric pressure chemical ionisation mass spectrometry (APCI-MS) showed that the antibacterial activity of G 1 was attributable to a phenylcoumarin dimer, while the introduction of syringyl units reduced antibacterial activity.

Bio-inspired borate cross-linked pulp foam (PF) with high porosity and low density can be widely used in many fields. However, PF is flammable, and lack of mechanical strength and antibacterial activity. To solve these issues, an ultra-strong PF was prepared by incorporation of chitosan and cationic polyacrylamide (CPAM). Results showed that the obtained PF exhibited highly improved mechanical properties (the compressive strength (485 kPa at a strain of 50%) was over 6 times higher compared with the borate cross-linked PF without chitosan and CPAM, and it was even higher than most of the reported cellulose-based porous materials). Also, the prepared PF has good performance on fire-retardance (hard to light), thermal insulation, antibiosis and sound absorption, due to the synergistic actions of borate, chitosan and CPAM. Additionally, spent liquor in preparing PF could be fully recycled, and thus this sustainable approach has potential for large-scale production of high-performance PF., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Development of recombinant enzymes as industrial biocatalysts or metabolic pathway elements requires soluble expression of active protein. Here we present a two-step strategy, combining a directed evolution selection with an enzyme activity screen, to increase the soluble production of enzymes in the cytoplasm of E. coli. The directed evolution component relies on the innate quality control of the twin-arginine translocation pathway coupled with antibiotic selection to isolate point mutations that promote intracellular solubility. A secondary screen is applied to ensure the solubility enhancement has not compromised enzyme activity. This strategy has been successfully applied to increase the soluble production of a fungal endocellulase by 30-fold in E. coli without change in enzyme specific activity through two rounds of directed evolution., (© 2022. Springer Science+Business Media, LLC, part of Springer Nature.)

Psilocybin, a drug most commonly recognized as a recreational psychedelic, is quickly gaining attention as a promising therapy for an expanding range of neurological conditions, including depression, anxiety, and addiction. This growing interest has led to many recent advancements in psilocybin synthesis strategies, including multiple in vivo fermentation-based approaches catalyzed by recombinant microorganisms. In this work, we show that psilocybin can be produced in biologically relevant quantities using a recombinant E. coli strain in a homebrew style environment. In less than 2 days, we successfully produced approximately 300 mg/L of psilocybin under simple conditions with easily sourced equipment and supplies. This finding raises the question of how this new technology should be regulated as to not facilitate clandestine biosynthesis efforts, while still enabling advancements in psilocybin synthesis technology for pharmaceutical applications. Here, we present our homebrew results, and suggestions on how to address the regulatory concerns accompanying this new technology.

Catalytic transformation of biomass-derived furans into value-added chemicals and biofuels has received considerable interest recently. In this work, aldehyde dehydrogenases (ALDHs) were identified from Comamonas testosteroni SC1588 for the oxidation of bio-based furans into furan carboxylic acids. Of the whole-cell biocatalysts constructed, Escherichia coli expressing a vanillin dehydrogenase (E. coli_CtVDH1) proved to be the best for the oxidation of 5-hydroxymethylfurfural (HMF). 5-Hydroxymethyl-2-furancarboxylic acid (HMFCA) was obtained in the yield of approximately 92 % within 12 h using this recombinant strain when the HMF concentration was up to 200 mM. In a fed-batch process, 292 mM of HMFCA was produced within 20.5 h, thereby providing a productivity as high as 2.0 g/L h. Other furan carboxylic acids were synthesized in the yields of 83-95%. Besides, the partially purified HMF was smoothly converted into HMFCA by this recombinant strain, with a 90% yield., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Psilocybin, the prodrug of the psychoactive molecule psilocin, has demonstrated promising results in clinical trials for the treatment of addiction, depression, and post-traumatic stress disorder. The development of a psilocybin production platform in a highly engineerable microbe could lead to rapid advances towards the bioproduction of psilocybin for use in ongoing clinical trials. Here, we present the development of a modular biosynthetic production platform in the model microbe, Escherichia coli. Efforts to optimize and improve pathway performance using multiple genetic optimization techniques were evaluated, resulting in a 32-fold improvement in psilocybin titer. Further enhancements to this genetically superior strain were achieved through fermentation optimization, ultimately resulting in a fed-batch fermentation study, with a production titer of 1.16 g/L of psilocybin. This is the highest psilocybin titer achieved to date from a recombinant organism and a significant step towards demonstrating the feasibility of industrial production of biologically-derived psilocybin., (Copyright © 2019 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.)

Curcuminoids (cus) have attracted increasing attention because of the antioxidant, anticancer, and antitumor activities while their production is limited because of its main source, turmeric plant, demonstrates extensive seasonal variation. In this study, we constructed Escherichia coli co-culture system for the rapid production of curcuminoids from glucose. Firstly, the overexpression of curcuminoid synthase and four different strategies related to increasing the intracellular malonyl-CoA pool were conducted in engineered E. coli. We found that bisdemethoxycurcumin (BDMC) is the main product and that high level of malonyl-CoA pool is essential for BDMC production. We also obtained the maximum titer (13.8 mg L -1 ) of BDMC within 4 h by fast preparation directly from p-coumaric acid. Secondly, we developed a process for BDMC synthesis from glucose using a co-culture system where an E. coli strain is used to produce p-coumaric acid from glucose and another E. coli strain converted p-coumaric acid into the final product. Compared to the mono-culture system, the co-culture is more potent and resulted in 6.28 mg L -1 of BDMC from glucose within 22 h of fermentation in a 3-L bioreactor. This is the first time a co-culture method is employed for the production of curcuminoids from glucose in a lab scale bioreactor. This system provides a new method transforming inexpensive substrate into value-added products., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)