INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES

Calnexin interacts with B-cell receptor-associated protein 31 (Bap31) to mediate coelomocyte phagocytosis and Vibrio splendidus clearance in Apostichopus japonicus
Tong L, Fu W, Zhang C, Liu Z and Guo M
Calnexin serves as a lectin chaperone located on the endoplasmic reticulum membrane and functions in glycoprotein folding and synthesis quality control, as well as in Ca storage. Calnexin is extensively documented to participate in host immunity in the endoplasmic reticulum. However, the functions and fundamental mechanisms of calnexin in the invertebrate innate defence remain largely unknown. In this research, the complete cDNA sequence for calnexin from Apostichopus japonicus (Ajcalnexin) was cloned, revealing a 1779 bp open reading frame that codes for 592 amino acids, 113 bp 5'-Untranslated Region (UTR), and 3251 bp 3'-UTR. Upon Vibrio splendidus infection, both AjCalnexin mRNA and protein levels were significantly increased in coelomocytes. Knocking down Ajcalnexin with specific siRNAs significantly decreased coelomocyte phagocytosis, reducing the intracellular load of V. splendidus. By contrast, overexpression of AjCalnexin using recombinant AjCalnexin protein (rAjCalnexin) had the opposite effect. Moreover, B-cell receptor-associated protein 31 of A. japonicus (AjBap31) was identified as an interacting partner of AjCalnexin, which positively regulates AjBap31 expression. Silencing Ajbap31 also decreased coelomocyte phagocytosis and inhibited the intracellular load of V. splendidus. Furthermore, phagocytosis levels and intracellular loads of V. splendidus in the coelomocytes of sea cucumbers treated with rAjCalnexin and siAjBap31 were significantly lower than those in rAjCalnexin- and siNC-treated sea cucumbers. Collectively, we provide the first functional evidence that the AjCalnexin-AjBap31 axis plays a crucial role in host immune defence by mediating coelomocyte phagocytosis in A. japonicus during V. splendidus infection. These findings enhance understanding of the regulatory mechanism of phagocytosis in echinoderms and offer theoretical insights for preventing and controlling skin ulcer syndrome in sea cucumbers.
Hypoglycemic effects of a new heteropolysaccharide from common bean (Phaseolus vulgaris L.) seeds in type 2 diabetes mellitus mice via modulating gut microbiota
Qu Y, Xu M, Yuan F, Zhang H, Li H, Guo R, Yu J, Ren Q, Wang R, Wang P and Wang H
Type 2 diabetes poses significant health issues worldwide; however, relatively few effective treatment strategies are currently available. This research seeks to explore the potential hypoglycemic impact of compounds derived from common bean (Phaseolus vulgaris L.) by structurally characterizing a new type of heteropolysaccharide (CIE2-F) and evaluating its hypoglycemic effects in a murine model. CIE2-F primarily comprises 10 monosaccharides, Mw: 9.25 × 10 Da. The polysaccharide exhibited significant anti-obesity effects, alleviated pathological liver damage, and reduced hyperglycemia. In addition, the polysaccharide mitigated insulin resistance and regulated dyslipidemia by increasing serum HDL-C and reducing LDL-C, total cholesterol, and triglycerides in diabetic mice. Furthermore, 16S rRNA sequencing revealed that CIE2-F enriched beneficial gut microbiota, including Akkermansia and Verrucomicrobia, while decreasing pathogenic bacteria.
Constructing guar hydroxypropyltrimonium chloride continuous segregated network structure for preparation of biobased conductive film
Lin Z, Lu Y, Wei X, Huang B and Xu C
Stretchable bioelectronics advancements have placed higher demands on conductive elastic film. However, the high conductivity of elastomers largely relies on the substantial content of costly conductive fillers while being environmentally unfriendly. Herein, in order to achieve a win-win situation for the economy and the environment, guar hydroxypropyltrimonium chloride (CGG) was introduced in epoxy natural rubber (ENR) to prepare biobased conductive film. During film-forming, CGG is selectively fixed around the latex particles, thereby forming a continuous segregated network. This structure can be transformed into nanofluidic channels upon hygroscopic, resulting in low volume resistance of 211 Ω·cm (≈280 times decrease). Simultaneously, the toughness of the film is increased to 10.8 MJ/m (≈20 times increase) due to the "reinforced concrete structure" effect of the network of CGG. Notably, the presence of segregated network also improved the response to strain (gauge factor of 19.1) and humidity (relative resistance change of 95.9 %). Therefore, the material can be used as wearable flexible sensors. This study not only reveals the formation process of segregated structures in detail but also has significantly advanced our comprehension of biosourced conductive film.
Ultrasensitive and rapid detection of organophosphates using a dual-signal naked-eye hydrogel sensor based on acetylcholinesterase inhibition
Wang J, Huang Y, Kuai Z, Zhang Y, Shen Q, Tian P, Nong W, Jiang W, He Y, Ran N, Yin Y, Li T and Luo Q
Accurate determination of pesticide residues is crucial for food safety. A self-calibration method was developed for dual-signal "naked-eye" detection of organophosphorus pesticides (OPs) using bifunctional gold nanozymes (AuNEs). OPs inhibit the cascade reaction of acetylcholinesterase/choline oxidase (AChE/CHO) to reduce hydrogen peroxide (HO) production, which affects the AuNE-catalyzed color reaction and quenches the fluorescence of AuNEs with the assistance of Fe. The multi-enzyme cascade system can be integrated into hydrogel sheets for smartphone-assisted digital, quantitative, and onsite detection of OPs in real food samples by analyzing the linear changes in colorimetric and fluorometric signals, which closely match liquid chromatography-mass spectrometry (LC-MS) results. This method displays a lowest 'naked-eye' detection concentration of 7 ppb, a wide linear range (0-2000 ng/mL), and particularly the advantage of anti-interference via self-calibration when one of the signals is abnormal.
High modulus and strength polyurethane film synthesized from lignin-based polyol with various lignin contents and NCO/OH molar ratios
Zhang Y, Wang C, Liang J, Wang M, Fu Y, Zhang Y, Tian G and Wang Z
This study explored the synthesis of lignin-polyol (LP) by liquefaction of Kraft lignin in polyethylene glycol and glycerol. LP23 (23 wt% lignin) and LP41 (41 wt% lignin) were obtained with remarkable liquefaction yields of 97.43 % and 93.75 %, respectively. LP-based polyurethane film (LP-PUF) was then fabricated by reacting LP23 and LP41 with hexamethylene diisocyanate. Mechanical properties and hydrophobicity of LP-PUF were optimized by varying NCO/OH molar ratios. LP23-PUF1.9 with NCO/OH of 1.9 showed excellent tensile strength of 34.28 MPa and Young's modulus of 233.27 MPa, while LP41-PUF2.0 with NCO/OH of 2.0 exhibited good tensile strength of 26.03 MPa and Young's modulus of 260.66 MPa. LP23-PUF2.0 displayed high hydrophobicity as indicated by the water contact angle of 96.8° and low surface free energy of 15.68 mN/m. Glass transition temperature (Tg) of LP-PUF varied depending on lignin content and NCO/OH molar ratio. Specifically, the increase of KL content from 23 % to 42 % induced big rise of Tg by 8 °C. The NCO/OH induced change of Tg was relatively weak, as indicated by the small increase of -2.71 °C of LP41-PU1.4 to -1.81 °C of LP41-PUF2.0. The results of this work offer insights for lignin utilization as structural component of high modulus and high strength polyurethane film.
Least hemolytic, 12.6 kDa, plasmin-like fibrinolytic protease from marine Penicillium steckii KU1
Kunhiraman S, Haridas M, Basheer SM, Chellappan S and Abdulhameed S
A novel fibrinolytic enzyme, from the marine fungus Penicillium steckii KU1, was purified to electrophoretic homogeneity. The fibrinolytic protease was purified to 13.56 times with a specific activity of 57.64 U/mg and final yield of 13.93 %. It was found to be a monomeric protein of 12.6 kDa, having optimum activity at 30 °C and isoelectric pH 8.0. It is a plasmin-like enzyme, showing resemblance to ATP-dependent zinc metalloprotease. Its activity is enhanced by Zn, and inhibited by ethylenediaminetetraacetic acid (EDTA), Co and Fe. The enzyme interaction with substrate azocasein was endothermic and with inhibitor EDTA exothermic. The K, V, K and catalytic efficiency of the enzyme for azocasein were determined to be 142.71 μg mL, 285.71 μg min mL, 6.35 S and 4.45 × 10 S μg mL respectively. It hydrolyzed all three chains of fibrinogen within 9 h, and dissolved fibrin completely within 24 h. 2 mg/mL enzyme could dissolve blood clot completely within 30 min, with negligible hemolysis (2.60 %). Lowering the immunogenicity by the application of natural or engineered small proteins is a strategy to enhance the safety and efficacy of thrombolytic therapy. Hence, the present 12.6 kDa, plasmin-like fibrinolytic enzyme appears worthy of further investigations towards a thrombolytic therapeutic.
Novel bionanocomposite of grafted chitosan-phthalic anhydride/CoO nanoparticles for efficient removal of brilliant green dye: Adsorption optimization using Box-Behnken design
Abdulhameed AS, Al Omari RH, Abualhaija M and Algburi S
A novel bionanocomposite of grafted chitosan-phthalic anhydride/CoO nanoparticles (CHT-PHT/CoO) was synthesized and used for the elimination of brilliant green (BG) dye from aquatic systems. The CHT-PHT/CoO material underwent several instrumental characterizations including, XRD, BET, FTIR, FESEM-EDX, and pH examinations. The impact of the key uptake factors, namely A: CHT-PHT/CoO dose, B: starting solution pH, and C: contact duration, on the effectiveness of BG removal, was mathematically optimized using the response surface methodology (RSM). The ideal conditions of the maximum BG elimination (96.05 %) according to the desirability function are as follows: A: CHT-PHT/CoO dose (0.044 g); B: pH ~ 10; and C: contact duration (34.6 min). The analysis of adsorption kinetics and equilibrium demonstrates a strong fit to the pseudo-first-order model, and the Freundlich isotherm model confirms the occurrence of multilayer adsorption. The highest adsorption capacity of CHT-PHT/CoO for BG was determined to be 425.09 mg/g at a temperature of 25 °C. This study highlights the development of a practical bionanocomposite adsorbent that has a favorable ability to absorb organic dyes from wastewater. The current work offers a sustainable and efficient method of reducing the environmental impact of industrial dye pollutants by utilizing the distinctive properties of CHT-PHT/CoO bionanocomposite.
Characterizing the collateral activity of CRISPR/Cas13 in mammalian cells: Implications for RNA editing and therapeutic applications
Wan Y, Huang C, Feng D, Wang L, Lin X, Zhao X, Han L, Zhu Y, Hao L, Du H and Huang L
The CRISPR/Cas13 system has garnered attention as a potential tool for RNA editing. However, the degree of collateral activity among various Cas13 orthologs and their cytotoxic effects in mammalian cells remain contentious, potentially impacting their applications. In this study, we observed differential collateral activities for LwaCas13a and RfxCas13d in 293 T and U87 cells by applying both sensitive dual-fluorescence (mRuby/GFP) reporter and quantifiable dual-luciferase (Fluc/Rluc) reporter, with LwaCas13a displaying notable activity contrary to previous reports. However, significant collateral RNA cleavage exerted only a modest impact on cell viability. Furthermore, collateral activity of LwaCas13a mildly impeded, but did not arrest, porcine embryo development. Our findings reveal that distinct collateral RNA cleavage by Cas13 slightly suppresses mammalian cell proliferation and embryo development. This could account for the lack of reported collateral effects in numerous prior studies and offers new insights into the implications of the collateral activity of Cas13 for clinical application.
Inhalable multi-stimulus sensitive curcumin-alginate nanogels for scavenging reactive oxygen species and anti-inflammatory co-ordination to alleviate acute lung injury
Cai J, Zhong H, Luo J, Huang X, Xu Q and Li P
Acute lung injury (ALI) is one of the most common and extremely critical clinical conditions, which progresses with an inflammatory response and overproduction of reactive oxygen species (ROS), leading to oxidative damage to the lungs. Curcumin (Cur) has great potential in treating ALI due to its excellent antioxidant and anti-inflammatory effects. In this study, Cur and alginate were cross-linked by zinc ions and intermolecular hydrogen bonding to form an inhalable aqueous nanogel system to overcome Cur's low solubility and bioavailability. Cur-alginate (ZA-Cur) nanogels exhibited superior antioxidant properties and down-regulated inflammation-associated factors in vitro with controlled-release behavior under multi-stimulus conditions such as temperature, pH, and ions. Meanwhile, the nanogels system could effectively scavenge cellular ROS to repair oxidative stress damage. In a mice model of ALI, tracheal nebulised inhalation of ZA-Cur nanogels down-regulated the expression of inflammation-related genes such as TNF-α, IL-1β, and IL-6, as well as modulated MDA content and CAT activity to attenuate oxidative stress injury, showing promising lung-protective effects. In conclusion, this work developed inhalable ZA-Cur nanogels to decelerate the progression of lesions in ALI by scavenging intracellular ROS and alleviating inflammation simultaneously, which may be a promising strategy for treating ALI.
Intelligent active packaging of sodium alginate and pectin mixed with Aronia melanocarpa anthocyanins and tea polyphenols for shrimp freshness monitoring and preservation
Chen S, Zhang H, Jiang Z, Ding X, Chen W, Ma N, Xu S and Yang L
In this study, an intelligent active packaging film was developed using sodium alginate (SA) and pectin (PC) as the film matrix, with Aronia melanocarpa anthocyanins (AMA) as a pH-sensitive indicator and tea polyphenol (TP) added to stabilize the anthocyanins. The results demonstrated that AMA and TP formed hydrogen bonds with polysaccharides, which reduced the surface roughness of the film and enhanced the compatibility of the component. The interaction between TP and AMA improved the stability of AMA, leading to an increase in anthocyanin retention rate from (29.56 ± 1.22)% to (40.67 ± 1.83)% after 4 days of UV irradiation. The addition of TP significantly enhanced the tensile strength (from 3.13 MPa to 4.26 MPa), UV-blocking properties, and antioxidant activity (with DPPH and ABTS radical scavenging activities being 4.8 and 9.6 times higher than those of the SA/PC film), as well as the antibacterial properties of the film. Additionally, the film exhibited a distinct color response to pH changes. Finally, the films were successfully applied to preserve shrimp and provide real-time visual monitoring of freshness. The results indicated that the SA/PC/AMA-2/TP film extend the shelf life of shrimp by approximately 12 h compared with the control group, making it a promising new food packaging material with potential applications.
Tailoring the morphology and antibacterial activity of PBAT and thermoplastic cassava starch blown films with phosphate derivatives
Wongphan P, Nerín C and Harnkarnsujarit N
Phosphate derivatives contain a high number of reactive groups that interact functionally with various polymers. Tetrasodium pyrophosphate (Na₄P₂O₇), sodium tripolyphosphate (Na₅P₃O₁₀), and sodium hexametaphosphate (Na₆(PO₃)₆) were incorporated into bioplastic polybutylene-adipate-terephthalate (PBAT) blended with thermoplastic cassava starch (TPS) in blown films. Their physicochemical, morphological, thermal, and antimicrobial properties were investigated. PBAT/TPS blended films were compounded via blown film extrusion to produce functional packaging. Infrared spectra indicated starch modification through the disruption of anhydroglucose monomer units, analyzed by ATR-FTIR, providing a more amorphous fraction and altering the properties of the films. PBAT/TPS films containing phosphate compounds exhibited non-homogeneous structures, with dispersed clumps within the film matrices that decreased tensile strength. The incorporation of phosphate compounds modified the storage modulus and relaxation temperature of PBAT/TPS films, influencing molecular mobility, decreasing heat transfer efficiency in seal strength, and enhancing stiffness due to starch disruption and interaction between the phosphate compound and the PBAT/TPS matrix. Wettability and permeability of PBAT/TPS films were modified by changes in polymer structure.
An injectable epoxidized soybean oil/gelatin-based photothermal biogel with remarkable rapid hemostasis capability for wound repair
Wang Z, Wu T, Zhao F, Zhao C, Ma F, Song H, Chen L, Wang W and Xing J
The development of wound dressings with rapid hemostasis, antibacterial activity without the addition of antibiotics and on-demand removability that effectively avoid secondary damage to the wound during replacement still faces significant challenges. Herein, injectable epoxidized soybean oil/gelatin-based photothermal biogel with outstanding tissue adhesion, on-demand removability, shape-adaptability, and antibacterial performance is prepared as a removable wound dressing for wound repair. The biogel is composed of two types of hydrophilic/hydrophobic three-dimensional network structures, which interweave together through dynamic imine bonds, coordination bonds and numerous hydrogen bonds to synergistically improve injectability, self-healing, tissue adhesion, and compressive performance of the biogel. Moreover, the prepared EG-02 biogel not only has excellent thermal stability, biodegradability, hemocompatibility, and RBCs and platelet adhesion properties, but also displays outstanding cytocompatibility and the ability to promote cell migration. Furthermore, the EG-02 biogel treated with a near-infrared (NIR) laser (808 nm, 0.2 W·cm) exhibits prominent photothermal cycling stability and antibacterial performance. Notably, the EG-02 biogel presents remarkable rapid hemostasis capability, with the hemostatic time greatly shortened to 40 s and the blood loss significantly reduced to 89.2 mg. Therefore, the injectable photothermal biogel, as a fascinating candidate for on-demand removable wound dressing, has shown promising application prospects in wound repair.
Exploring the conformational space of the mobile flap in Sporosarcina pasteurii urease by cryo-electron microscopy
Mazzei L, Tria G, Ciurli S and Cianci M
To fully understand enzymatic dynamics, it is essential to explore the complete conformational space of a biological catalyst. The catalytic mechanism of the nickel-dependent urease, the most efficient enzyme known, holds significant relevance for medical, pharmaceutical, and agro-environmental applications. A critical aspect of urease function is the conformational change of a helix-turn-helix motif that covers the active site cavity, known as the mobile flap. This motif has been observed in either an open or a closed conformation through X-ray crystallography studies and has been proposed to stabilize the coordination of a urea molecule to the essential dinuclear Ni(II) cluster in the active site, a requisite for subsequent substrate hydrolysis. This study employs cryo-electron microscopy (cryo-EM) to investigate the transient states within the conformational space of the mobile flap, devoid of the possible constraints of crystallization conditions and solid-state effects. By comparing two cryo-EM structures of Sporosarcina pasteurii urease, one in its native form and the other inhibited by N-(n-butyl) phosphoric triamide (NBPTO), we have unprecedently identified an intermediate state between the open and the catalytically efficient closed conformation of the helix-turn-helix motif, suggesting a role of its tip region in this transition between the two states.
Fabrication of the carbon paste electrode modified with Trametes versicolor laccase immobilized on carboxyl functionalized multi-walled carbon nanotubes and its application for measurement of dopamine
Moradpour H, Forootanfar H, Ameri A and Beitollahi H
Dopamine (DA) shows numerous roles in a wide range of physiological and pathological processes. In this study, an immobilized laccase-derived biosensor was developed for DA detection. The carboxyl functionalized multi-walled carbon nanotubes (MWCNTs-COOH) was applied for immobilization of laccase from Trametes versicolor (TvLac). According to Plackett-Burman statistical design, the optimum conditions showed at 5 mg/mL of MWCNTs-COOH, 25 mM phosphate buffer (pH 6.0), sonication time for 15 min, 2.5 U/mg of enzyme concentration, immobilization time for 4 h at 4 °C, and rotation at 100 rpm. At these conditions, the experimental and predicted specific activities were 14.19 ± 1.41 U/mg and 13.99 ± 1.54 U/mg, respectively. The activity of immobilized TvLac was >90 % at 60 °C and pH 7.0 as well as after 10 sets of uses. The carbon paste electrode (CPE) modified with the immobilized TvLac was then fabricated, characterized and applied as a biosensor (TvLac@MWCNTs-COOH/CPE) for determination of DA. The mean of diffusion coefficient for DA was considered to be 9.1 × 10 cm/s. The TvLac@MWCNTs-COOH/CPE represented a linear dynamic range of 0.005-100.0 μM with detection limit of 1.0 nM. The TvLac@MWCNTs-COOH/CPE might be introduced as a suitable sensor for monitoring of DA in real specimens which merit further studies.
Structural, mechanical, and cytocompatibility characteristics of hybrid scaffolds from chitosan/decellularized testicular ECM
Hamzeh M, Movahedin M, Ganji F and Ghiaseddin A
Tissue engineering has facilitated the development of novel therapeutic strategies for male reproductive disorders. Decellularized extracellular matrix (ECM) scaffolds provide a wide range of functional components that promote cellular behavior. This research aimed to develop reinforced scaffolds for testicular tissue engineering by combining testicular ECM (TE) derived pre-gel with chitosan (CS) solution at varying ratios (TE25/CS75, TE50/CS50, and TE75/CS25). To determine the optimum ratio of TE to CS solution, final scaffold properties were investigated including pore size, porosity, mechanical strength, swelling ratio, degradation rate followed by in-vitro biological evaluations. All groups revealed an interconnected porous structure with high porosity (from 76.6 % to 90.9 %) and adequate pore sizes (between 50 and 226 μm), while the pores of TE50/CS50 scaffold were distributed more uniformly. The mechanical properties of scaffolds were enhanced by combining CS with TE, whereas their swelling ratio decreased. It was observed that the scaffolds' degradation rate rose substantially as the ratio of TE to CS increased. The MTT assay revealed that none of the scaffolds exhibited cytotoxic properties. The results of this study demonstrated that all fabricated hybrid scaffolds, especially the TE50/CS50, have potential for testicular tissue engineering applications.
Analysis on the involvement of phosphoglycerate mutase 1 in the aerobic glycolysis of melanoma cells
Wang Q, Lang Z, Yin G, Zheng P, Lv H, Fang H, Wang T, Wang K and Zhao L
The aim of this study was to investigate the mechanism through which phosphoglycerate mutase 1 (PGAM1) drives aerobic glycolysis and promotes tumor aggressiveness in melanoma and to evaluate its potential as a therapeutic target.
Structural characterization of a polysaccharide from Scutellaria baicalensis Georgi and its immune-enhancing properties on RAW264.7 cells
Xiong S, Li N, Shi S, Zhao Y, Chen J, Ruan M, Xu Y, Liu R, Wang S and Wang H
A novel polysaccharide SPS01-2 (87.5 kDa) was isolated from the roots of Scutellaria baicalensis Georgi. Monosaccharide composition revealed that SPS01-2 consists of rhamnose, arabinose, galactose, galacturonic acid, and glucuronic acid in ratio of 4.4: 67.1: 22.2: 6.3: 1.2. Further investigations using methylation, NMR, and mass spectrometry indicated that SPS01-2 is classified as a type II arabinogalactan (AG-II) with a minor presence of type I rhamnogalacturonan (RG-I). The core structure alternates between 1,2/1,2,4-α-L-Rhap and 1,4-α-D-GalpA, with branches including 1,3,6-β-D-Galp, 1,3-β-D-Galp, T-β-D-Galp, and T-α-L-Rhap. The RG-I regions are linked to 1,6-β-D-Galp, and 1,3,6-β-D-Galp units. Numerous arabinan branches, featuring multiple branching points, are attached to the O-3 position of galactose. Additionally, T-β-D-Galp, 1,6-β-D-Galp, and T-β-D-4-OMe-GlcpA are also linked to galactose in the backbone. Furthermore, SPS01-2 demonstrated potential immune-enhancing properties by dose-dependently increasing proliferation, phagocytosis, and the production of nitric oxide and cytokines (TNF-α, IL-6, and IL-1β) in RAW264.7 cells. It also enhanced the expression of CD80, CD86, and MHC-II at concentrations ranging from 5 to 200 μg/mL. Moreover, the immunostimulatory activity of SPS01-2 was significantly reduced when branch linkages were removed through partial acid hydrolysis. Our findings indicate that SPS01-2 could serve as a natural immunostimulant in the food and pharmaceutical sectors.
Chitosan-based nanoarchitectures for siRNA delivery in cancer therapy: A review of pre-clinical and clinical importance
Bian X, Yu X, Lu S, Jia L, Li P, Yin J and Tan S
The gene therapy has been developed into a new cancer treatment option. Now that we know which molecular components contribute to carcinogenesis, we may use gene therapy to target particular signalling pathways in cancer treatment. Problems with gene therapy include genetic tool degradation in blood, off-targeting features, and inadequate tumor site accumulation; new delivery mechanisms are needed to address these issues. A polysaccharide made from chitin, chitosan has found extensive use in the creation of nanoparticles. The delivery of genes in the treatment of illnesses, particularly cancer, has made use of nanostructures modified with chitosan. Topics covered in this review center on cancer treatment using chitosan-based polymers for siRNA delivery. This study aims to assess the potential of chitosan nanoparticles for the simultaneous administration of siRNA and anti-cancer medications. In cancer treatment, these nanoparticles can transport phytochemicals or chemotherapeutics together with siRNA. In addition, chitosan nanoparticles loaded with siRNA can inhibit the growth and spread of human malignancies by delivering siRNA that targets particular genes. Chitosan nanoparticles loaded with siRNA can heighten the responsiveness of cancer cells. Future therapeutic applications of chitosan nanoparticles may open the path for cancer treatment, thanks to their biocompatibility and biosafety.
Characterization of a novel cold-active β-Xylosidase from Parabacteroides distasonis and its synergistic hydrolysis of beechwood xylan
Chen J, Huang B, Liu Y, Sun X, Xiong L, Zhu T, Yao X, Hu H and Liu H
Although β-xylosidases have broad applications in fields such as food and medicine, there is limited research on cold-active β-xylosidases. This study cloned a novel cold-active β-xylosidase XYL13 from Parabacteroides distasonis. The purified XYL13 exhibited the highest activity at 40 °C, with 42 % and 25 % of its maximum activity at 4 °C and 0 °C, respectively. Meanwhile, XYL13 predominantly produces X1 while degrading X2-X6. Additionally, XYL13 showed a significant synergistic effect (18.5-fold) with endo-xylanase for degrading beechwood xylan at low temperatures. Moreover, the site-directed mutagenesis assay indicated that Ile269 and Glu621 are essential catalytic sites of XYL13. Finally, molecular docking showed that XYL13 has an excellent binding effect with X2-X6, verifying that XYL13 can effectively cut X2-X6 to produce xylose. These results highlight the potential of cold-adapted XYL13 from P. distasonis for application in the food industry.
A comprehensive review of lignin-reinforced lignocellulosic composites: Enhancing fire resistance and reducing formaldehyde emission
Iswanto AH, Hua LS, Hussin MH, Hamidon TS, Hajibeygi M, Manurung H, Solihat NN, Nurcahyani PR, Lubis MAR, Antov P, Savov V, Kristak L, Kawalerczyk J, Osvaldová LM, Farid S, Selvasembian R and Fatriasari W
The rising environmental concerns and the growing demand for renewable materials have surged across various industries. In this context, lignin, being a plentiful natural aromatic compound that possesses advantageous functional groups suitable for utilization in biocomposite systems, has gained notable attention as a promising and sustainable alternative to fossil-derived materials. It can be obtained from lignocellulosic biomass through extraction via various techniques, which may cause variability in its thermal, mechanical, and physical properties. Due to its excellent biocompatibility, eco-friendliness, and low toxicity, lignin has been extensively researched for the development of high-value materials including lignin-based biocomposites. Its aromatic properties also allow it to successfully substitute phenol in the production of phenolic resin adhesives, resulting in decreased formaldehyde emission. This review investigated and evaluated the role of lignin as a green filler in lignin-based lignocellulosic composites, aimed at enhancing their fire retardancy and decreasing formaldehyde emission. In addition, relevant composite properties, such as thermal properties, were investigated in this study. Markedly, technical challenges, including compatibility with other matrix polymers that are influenced by limited reactivity, remain. Some impurities in lignin and various sources of lignin also affect the performance of composites. While lignin utilization can address certain environmental issues, its large-scale use is limited by both process costs and market factors. Therefore, the exact mechanism by which lignin enhances flame retardancy, reduces formaldehyde emissions, and improves the long-term durability of lignocellulosic composites under various environmental conditions remains unclear and requires thorough investigation. Life cycle analysis and techno-economic analysis of lignin-based composites may contribute to understanding the overall influence of systems not only at the laboratory scale but also at a larger industrial scale.
De novo design of Na-activated lipopeptides with selective antifungal activity: A promising strategy for antifungal drug discovery
Gao N, Fang C, Bai P, Wang J, Dong N, Shan A and Zhang L
In recent years, invasive fungal infections have posed a significant threat to human health, particularly due to the limited availability of effective antifungal medications. This study responds to the urgent need for powerful and selective antifungal agents by designing and synthesizing a series of lipopeptides with lipoylation at the N-terminus of the antimicrobial peptide I6. Compared to the parent peptide I6, lipopeptides exhibited selective antifungal efficacy in the presence of Na. Among the variants tested, C-I6 emerged as the most effective, with an average effective concentration of 5.3 μM against 12 different fungal species. C-I6 combated fungal infections by disrupting both cytoplasmic and mitochondrial membranes, impairing the proton motive force, generating reactive oxygen species, and triggering apoptosis in fungal cells. Importantly, C-I6 exhibited minimal hemolysis and cytotoxicity while effectively inhibiting fungal biofilm formation. In vivo experiments further validated the safety and therapeutic potential of C-I6 in treating fungal skin infections. These findings underscore the significance of lipoylation in enhancing the efficacy of antimicrobial peptides, positioning C-I6 as a promising candidate in fighting against drug-resistant fungal infections.