Hybrid Amyloid-Chitin Nanofibrils for Magnetic and Catalytic Aerogels.

In the quest for a sustainable and circular economy, it is essential to explore environmentally friendly alternatives to traditional petroleum-based materials. A promising pathway toward this goal lies in the leveraging of biopolymers derived from food waste, such as proteins and polysaccharides, to develop advanced sustainable materials. Here, we design versatile hybrid materials by hybridizing amyloid nanofibrils derived by self-assembly of whey, a dairy byproduct, with chitin nanofibrils exfoliated from the two distinct allomorphs of α-chitin and ß-chitin, extracted from seafood waste. Various hydrogels and aerogels were developed via the hybridization and reassembly of these biopolymeric nanobuilding blocks, and they were further magnetized upon biomineralization with iron nanoparticles. The pH-phase diagram highlights the significant role of electrostatic interactions in gel formation, between positively charged amyloid fibrils and negatively charged chitin nanofibrils. Hybrid magnetic aerogels exhibit a ferromagnetic response characterized by a low coercivity (<50 Oe) and a high specific magnetization (>40 emu/g) at all temperatures, making them particularly suitable for superparamagnetic applications. Additionally, these aerogels exhibit a distinct magnetic transition, featuring a higher blocking temperature (200 K) compared to previously reported similar nanoparticles (160 K), indicating enhanced magnetic stability at elevated temperatures. Finally, we demonstrate the practical application of these hybrid magnetic materials as catalysts for carbon monoxide oxidation, showcasing their potential in environmental pollution control and highlighting their versatility as catalyst supports.

Curcumin in cancer therapy: Exploring molecular mechanisms and overcoming clinical challenges.

Cancer poses a significant global health burden, necessitating the widespread use of chemotherapy and radiotherapy as conventional frontline interventions. Although targeted therapy and immunotherapy have shown remarkable advancements, the challenges of resistance development and severe side effects persist in cancer treatment. Consequently, researchers have actively sought more effective alternatives with improved safety profiles. In recent years, curcumin, a natural polyphenolic phytoalexin, has garnered considerable attention due to its broad spectrum of biological effects. This concise review provides valuable insights into the role of curcumin in cancer therapy, with a focus on elucidating its molecular mechanisms in inducing programmed cell death of tumor cells and suppressing tumor cell metastasis potential. Additionally, we discuss the challenges associated with the clinical application of curcumin and explore current endeavors aimed at overcoming these limitations. By shedding light on the promising potential of curcumin, this review contributes to the advancement of cancer treatment strategies.

Cocoa bean shells: a review into the chemical profile, the bioactivity and the biotransformation to enhance their potential applications in foods.

During processing, cocoa bean shells (CBS) are de-hulled from the bean and discarded as waste. Undermined by its chemical and bioactive composition, CBS is abundant in dietary fiber and phenolic compounds that may serve the valorization purpose of this by-product material into prebiotic and functional ingredients. In addition, the cell-wall components of CBS can be combined through enzymatic feruloylation to obtain feruloylated oligo- and polysaccharides (FOs), further enhancing the techno-functional properties. FOs have attracted scientific attention due to their prebiotic, antimicrobial, anti-inflammatory and antioxidant functions inherent to their structural features. This review covers the chemical and bioactive compositions of CBS as well as their modifications upon cocoa processing. Physical, chemical, and enzymatic approaches to extract and bio-transform bioactive components from the cell wall matrix of CBS were also discussed. Although nonspecific to CBS, studies were compiled to investigate efforts done to extract and produce feruloylated oligo- and polysaccharides from the cell wall materials.

Diagnostic efficacy of joint detection of Xpert MTBRIF, TB-RNA and TB-DNA in bronchoalveolar lavage fluid for smear-negative pulmonary tuberculosis / 中国热带医学

@#Abstract: Objective　To investigate the diagnostic value of joint detection of Mycobacterium tuberculosis rifampicin resistance gene (Xpert MTB/RIF), Mycobacterium tuberculosis ribonucleic acid (TB-RNA) and Mycobacterium tuberculosis deoxyribonucleic acid (TB-DNA) in bronchoalveolar lavage fluid for smear-negative pulmonary tuberculosis. Methods A total of 806 patients with suspected smear-negative pulmonary tuberculosis admitted to our hospital from May 2020 to July 2022 were selected, 506 patients diagnosed as bacterial negative pulmonary tuberculosis by clinical, X-ray and sputum samples were classified as bacterial negative pulmonary tuberculosis group, and the other 300 patients with non-tuberculous pulmonary disease were classified as non-tuberculous pulmonary disease group. XpertMTB/RIF, TB-RNA and TB-DNA in bronchoalveolar lavage fluid of all patients were detected. With clinical, X-ray and sputum specimen examination of mycobacterium tuberculosis as the gold standard, the diagnostic efficacy of alveolar lavage solution Xpert MTB/RIF, TB-RNA and TB-DNA alone and in combination was analyzed. Results The positive detection rates of Xpert MTB/RIF, TB-RNA and TB-DNA in bronchoalveolar lavage fluid of the smear-negative pulmonary tuberculosis group and the non-tuberculosis pulmonary disease group were 69.96% (354/506) and 2.67% (8/300), 61.46% (311/506) and 5.00% (15/300), and 63.64% (322/506) and 8.00% (24/300), respectively. The rates in the smear-negative pulmonary tuberculosis group were higher than those in the non-tuberculosis lung disease group, and the differences were statistically significant (χ2=342.005, 246.930, 235.687, P<0.01). Compared with the gold standard, the sensitivity, specificity, accuracy, positive predictive value and negative predictive value of Xpert MTB/RIF in the diagnosis of smear-negative pulmonary tuberculosis were 69.96%, 97.33%, 80.15%, 97.79% and 65.77%, respectively; those values of TB-RNA were 61.46%, 95.00%, 73.95%, 95.40% and 59.38%, respectively; those values of TB-DNA were 63.64%, 92.00%, 74.19%, 93.06% and 60.00%, respectively; those values of combined diagnosis with Xpert MTB/RIF, TB-RNA and TB-DNA were 61.26%, 100.00%, 75.68%, 100.00% and 60.48%, respectively; the specificity and positive predictive value of combined detection were higher than those of single detection (P<0.05). Conclusions The joint detection of Xpert MTB/RIF, TB-RNA and TB-DNA in bronchoalveolar lavage fluid can improve the diagnostic efficacy of smear-negative pulmonary tuberculosis and is worthy of clinical promotion and application.

Functional Coating from Amyloid Superwetting Films.

Tailoring the hydrophilicity of solid surfaces with a strong affinity to water has been extensively explored in the last 20 years, but studies have been limited to the single function of wettability. Here, the multifunctional properties of tailored surface films are extended from exhibiting superwettability to facilitating biological activities. It is shown that amyloid fibrils can be universally coated onto various substrates, such as fabrics (non-woven organic masks), metal meshes, polyethersulfone (PES), glass, and more, endowing the resulting surfaces with excellent performance in oil/water mixture and emulsion separation, antifouling, and antifogging. Moreover, the biocompatible crosslinked amyloid fibril coatings can serve as a platform for biocatalytic activities by immobilizing enzymes, as shown in the 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) oxidation and Reactive Black 5 (RB5) degradation by laccase from Trametes versicolor. The study provides a universal approach to modifying surface morphology and chemical properties via fibrous protein templates, opening the way to unexplored bio-based applications and functionalities.

Combining phenolic grafting and laccase-catalyzed cross-linking: Effects on structures, technofunctional properties and human immunoglobulin E binding capacity of egg white proteins.

The efficiency of laccase-catalyzed protein cross-linking can be impacted by substrate protein structure and competing reactions. In this study, chemical grafting of ferulic acid (FA) on protein surface was applied to modulate the cross-linking of two inflexible globular proteins, lysozyme (LZM) and ovalbumin (OVA). The extent of FA-grafting was positively correlated with protein cross-linking extent, and determined the molecular weight profile and structures of the cross-linked product. While laccase-catalyzed reactions (with or without free FA mediator) did not lead to evident cross-linking of the native proteins, oligomeric (up to 16.4%), polymeric (up to 30.6%) FA-LZMs and oligomeric FA-OVA (5.1-31.1%) were obtained upon the enzymatic treatments. The cross-linking on the grafted FA sites occurred mainly through the formation of 8-5'-noncyclic-dehydro-diferulic linkages. The effects of investigated cross-linking approach on the emulsifying, foaming properties and the immunoglobulin E (IgE) binding capacity of LZM and OVA were also evaluated in relation to the structural properties of cross-linked proteins.

Laccase-catalyzed conjugation of potato protein (PPT) with selected pectic polysaccharides (PPS): Conjugation efficiency and emulsification properties.

The current study focused on the investigation of laccase-catalyzed conjugation of potato protein (PPT) with selected pectic polysaccharides (PPS) and modulation of the conjugation in order to obtain desired functional ingredients. PPS, including sugar beet pectin/arabinan, apple/citrus pectin and potato galactan, were evaluated as substrates in the conjugation reaction-catalyzed by laccases (Trametes versicolor-LacTv, Coriolus hirsutus-LacCh). LacCh exhibited a higher catalytic efficiency than LacTv. The reactivity of PPT/PPS and their ratio were determinants for their heteroconjugation. Both laccases exhibited the highest specificity towards the conjugation of PPT/sugar beet pectin. Predictive models were developed for conjugation efficiency and emulsification performance. The conjugation extent was negatively affected by the protein proportion and the protein proportion/enzyme concentration interaction; while the emulsification performance was positively correlated with the protein proportion and the protein proportion/reaction time interaction. This study contributed to the understanding of laccase-catalyzed conjugation reaction for the controlled synthesis of conjugated-PTT as functional ingredients.

Laccase-catalyzed oxidative cross-linking of tyrosine and potato patatin- and lysozyme-derived peptides: Molecular and kinetic study.

Laccase can catalyze the oxidative cross-linking of peptides, which is useful in the production of proteinaceous materials with enhanced functional properties. However, the kinetics and the pathway of this reaction remain unclear. In the present study, laccase-catalyzed oxidative cross-linking reaction was investigated through a combination of computational analysis, kinetic studies and end-product profiling using selected substrate models, including peptide AG-10 (AKKIVSDGNG) (without tyrosine) derived from lysozyme and tyrosine-containing peptide ST-10 (SYMTDYYLST) from potato protein (patatin), and tyrosine. Both laccases from Trametes versicolor (LacTv) and Coriolus hirsutus (LacCh) were used as biocatalysts. Laccase exhibited higher binding affinity and catalytic efficiency (kcat/Km) towards ST-10 and AG-10 than tyrosine. Among the laccases, LacCh showed higher kcat towards the substrate models than LacTv. Through the molecular docking, this result was attributed to the presence of the ASN206 at the cavity of LacCh. The end product profiles reveal the formation of homo-oligomers (> 5 units) of ST-10 in the reaction catalyzed by LacTv, while polymerization was favored by LacCh. These cross-linked products were identified to have a mix of oligo-tyrosine linkages. In contrast, the cross-linking of AG-10 required the presence of ferulic acid as mediator, which resulted in the formation of hetero-oligomers and polymers of AG-10. The knowledge obtained in the present study provide insight into an effective reaction for peptide cross-linking.