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Numerous clinical disorders have been linked to the etiology of dysregulated NLRP3 (NACHT, LRR, and PYD domain‐containing protein 3) inflammasome activation. Despite its potential as a pharmacological target, modulation of NLRP3 activity remains challenging. Only a sparse number of compounds have been reported that can modulate NLRP3 and none of them have been developed into a commercially available drug. In this research, we identified three potent NLRP3 inflammasome inhibitors, gymnoasins A‐C (1–3), with unprecedented pentacyclic scaffolds, from an Antarctic fungus Pseudogymnoascus sp. HDN17‐895, which represent the first naturally occurring naphthopyrone‐macrolide hybrids. Additionally, biomimetic synthesis of gymnoasin A (1) was also achieved validating the chemical structure and affording ample amounts of material for exhaustive bioactivity assessments. Biological assays indicated that 1 could significantly inhibited in vitro NLRP3 inflammasome activation and in vivo pro‐inflammatory cytokine IL‐1β release, representing a valuable new lead compound for the development of novel therapeutics with the potential to inhibit the NLRP3 inflammasome. [ABSTRACT FROM AUTHOR]

Herein the reaction of methy cinnamates with N‐Iodosuccinimide (NIS) is reported and the possible formation of dihydrobenzofuryl dimeric derivatives (DHBF), known for their biological activities, is explored. Having an oxidizing capacity, we studied the behavior of NIS with methyl ferulate and under optimized reaction conditions we obtained its DHBF dimer in 35% yield. It is worth to note that we did not obtain the DHBF in his natural form, but rather as the demethylated compound, likely due to dismutation reactions activated by the presence of water in the solvent. Methyl caffeate reacted with NIS to furnish the DHBF dimer in 15% yield, while methyl coumarate and methyl isoferulate did not give any form of DHBF dimers, showing the importance of a hydroxyl group in para position on an activated system and an electron‐rich aromatic ring. An electrochemical investigation by cyclic voltammetry was carried out on the three cinnamates and confirmed the correlation between dimerization and oxidation potential: methyl ferulate and methyl caffeate dimerize, while methyl coumarate, due to its higher oxidizing potential, does not. [ABSTRACT FROM AUTHOR]

Microbial biomineralization is a phenomenon involving deposition of inorganic minerals inside or around microbial cells as a direct consequence of biogeochemical cycling. The microbial metabolic processes often create environmental conditions conducive for the precipitation of silicate, carbonate or phosphate, ferrate forms of ubiquitous inorganic ions. Till date the fundamental mechanisms underpinning two of the major types of microbial biomineralization such as, microbially controlled and microbially induced remains poorly understood. While microbially-controlled mineralization (MCM) depends entirely on the genetic makeup of the cell, microbially-induced mineralization (MIM) is dependent on factors such as cell morphology, cell surface structures and extracellular polymeric substances (EPS). In recent years, the organic template-mediated nucleation of inorganic minerals has been considered as an underlying mechanism based on the principles of solid-state bioinorganic chemistry. The present review thus attempts to provide a comprehensive and critical overview on the recent progress in holistic understanding of both MCM and MIM, which involves, organic–inorganic biomolecular interactions that lead to template formation, biomineral nucleation and crystallization. Also, the operation of specific metabolic pathways and molecular operons in directing microbial biomineralization have been discussed. Unravelling these molecular mechanisms of biomineralization can help in the biomimetic synthesis of minerals for potential therapeutic applications, and facilitating the engineering of microorganisms for commercial production of biominerals. [ABSTRACT FROM AUTHOR]

On the basis of a novel ynol‐diene cyclization developed as a rapid access to tropone unit, the first divergent strategy to 17‐nor‐cephalotane diterpenoids has been successfully established. Combining with a bioinspired stereoselective dual hydrogenation, the divergent total synthesis of (+)‐3‐deoxyfortalpinoid F, (+)‐harringtonolide, (−)‐fortalpinoids M/N/P, and analog (−)‐20‐deoxocephinoid P have been achieved in 14–17 linear longest steps starting from commercially available materials. [ABSTRACT FROM AUTHOR]

The total syntheses of gochnatiolide D and ainsliadimer A were achieved through a streamlined one‐pot sequence starting from their biogenetic precursor dehydrozaluzanin C. These biomimetic, protecting group‐free syntheses involve the elegant orchestration of the highly diastereoselective hetero‐Diels‐Alder reaction of dehydrozaluzanin C, its subsequent hydrolysis to gochnatiolide D and finally an aldol reaction to ainsliadimer A, all harnessed by the hydrogen bond propensity and acidity of hexafluoroisopropanol (HFIP), which was utilized as the reaction solvent. [ABSTRACT FROM AUTHOR]

The synthesis of biomimetic thioesters for enzymatic studies of ketoreductase (KR) domains from polyketide synthases is described. A TBS-protected dihydroxyalkene fragment was synthesised by a sequence involving a Nagao acetate aldol reaction, a Mukaiyama propionate aldol reaction, and a methylene Wittig olefination. Fragment coupling to N -acetylcysteamine (SNAC) (E)-3-hydroxyhex-4-enethioates by an olefin cross-metathesis (OCM) and subsequent deprotection gave the potential KR product stereoisomers. An analogous OCM with a SNAC (E)-3-ketohex-4-enethioate did not give the desired KR precursor, but the reaction could successfully be replaced by a Horner–Wadsworth–Emmons olefination between a SNAC 3-ketothioester phosphonate and a TBS-protected dihydroxy aldehyde. After deprotection, an intramolecular cyclisation was observed that needs to be considered as a spontaneous side reactivity in the enzymatic assays. [ABSTRACT FROM AUTHOR]

The microstructure of bone consists of nano-hydroxyapatite (nano-HA) crystals aligned within the interspaces of collagen fibrils. To emulate this unique microstructure of bone, this work applied two biomimetic techniques to obtain bone-like microstructures in vitro, that is, combining the construction of collagen liquid crystal hydrogel (CLCH) with the application of a polymer-induced liquid precursor (PILP) mineralization process. Upon the elevation of pH, the collagen macromolecules within the collagen liquid crystal (CLC) were activated to self-assemble into CLCH, whose fibrils packed into a long and dense fiber bundle in high orientation, emulating the dense-packed matrix of bone. We demonstrated that the fibrillar mineralization of CLCH, leading to a bone-like nanostructured inorganic material part, can be achieved using the PILP crystallization process to pre-mineralize the dense collagen substrates of CLCH with CaCO3, immediately followed by the in situ mineral phase transformation of CaCO3 into weak-crystalline nano-HA. The combination of CLCH with the biomineralization process of PILP, together with the mineral phase transformation, achieved the in vitro simulation of the nanostructures of both the organic extracellular matrix (ECM) and inorganic ECM of bone. This design would constitute a novel idea for the design of three-dimension biomimetic bone-like material blocks for clinical needs. [ABSTRACT FROM AUTHOR]

The selective synthesis of biomimetic Fe/Mn complexes able to mimic the geometry and catalytic activity of enzymes possessing this cofactor is still a challenge. Herein, we discuss the stepwise synthesis, characterization, and magnetic properties of a Fe(II)/Mn(II) species and related Fe(II)/Fe(II) complexes. [ABSTRACT FROM AUTHOR]

Polymer hydrogels find extensive application in biomedicine, serving specific purposes such as drug delivery, biosensing, bioimaging, cancer therapy, tissue engineering, and others. In response to the growing threat of bacterial infections and the escalating resistance to conventional antibiotics, this research introduces a novel injectable, self‐healing antimicrobial hydrogel comprising bioactive aldolized hyaluronic acid (AHA) and quaternized chitosan (QCS). This designed QCS/AHA hydrogel incorporates self‐assembling peptide nanofibers (PNFs) and small‐sized silver nanoparticles (AgNPs) for tailored functionality. The resulting hybrid QCS/AHA/PNF/AgNPs hydrogel demonstrates impressive rheological characteristics, broad‐spectrum antimicrobial efficacy, and high biocompatibility. Notably, its antimicrobial effectiveness against Escherichia coli and S. aureus surpasses 99.9%, underscoring its potential for treating infectious wounds. Moreover, the rheological analysis confirms its excellent shear‐thinning and self‐healing properties, enabling it to conform closely to irregular wound surfaces. Furthermore, the cytotoxicity assessment reveals its compatibility with human umbilical vein endothelial cells, exhibiting no significant adverse effects. The combined attributes of this bioactive QCS/AHA/PNF/AgNPs hydrogel position it as a promising candidate for antimicrobial applications and wound healing. [ABSTRACT FROM AUTHOR]

The biomimetic synthesis of substituted tetrahydro coumestan (3–8) derivatives is accomplished from 4-hydroxycoumarins (1a–f) and cyclohexanone derivatives (2a–n) using a 20 mol% FeCl3·6H2O catalyst in DMSO solvent upon heating at 110 °C. The significant features of the present strategy are mild reaction conditions, easy handling, readily available starting materials, no need for dry solvents, additives, and inert atmospheric reaction conditions, broad substrate scope, good to excellent yields, and high atom economy. In addition, coumestan derivatives (9) were obtained from the corresponding tetrahydro coumestan derivatives by dehydrogenation with DDQ. Moreover, synthesizing naturally occurring coumestan, coumestrol dimethyl ether, and 4-O-methyl coumestrol validated the two-step synthetic route. [ABSTRACT FROM AUTHOR]

Various fascinating optical characteristics in organisms encourage scientists to develop biomimetic synthesis strategies and mimic their unique microstructure. Inspired by the Chameleon's skin with tunable color and superior flexibility, this work designs the evaporated‐induced self‐assembly technique to synthesize the chiral photonic crystal film. Ultrasonic‐intensified and additive‐assisted techniques synergistically optimize the film properties, on the aspects of optic and mechanic. The film shows considerable rigidity and superior flexibility, which can undergo multiple mechanical deformations. Without destroying the chiral nematic structure, the ultimate strain approaches 50%, which exceeds most cellulose‐derived film materials. It also integrates excellent optical performance. The film color can cover the total visible region by tuning the photonic bandgap and has angle‐dependent properties. It can make the response to humidity and solvents, and chromaticity variation reflects the degree of stimulation. Importantly, this structural‐dependent color change is reversible. Lastly, the photonic crystal materials with excellent mechanics and unique optics have been applied in the security. The anti‐counterfeiting material design contains photonic crystal ink, repeatable writing paper, information‐hiding film, and color‐changing labels, with the features of environmentally friendly, economical, non‐destructive, and convenient for authentication. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Hierarchically porous materials (HP materials) are believed one of the most hopeful matrix materials because of their distinctive multimodal pore structures and tremendous application potentials in the field of biomedicine. However, green and facile synthesis of hierarchically porous nanomaterials with beneficial water dispersibility and biocompatibility is still a great challenge. Herein, a novel biomimetic strategy is proposed to prepare the cell‐tailored double‐shelled HPCaCO3/CaF2 hollow nanospheres under the mediation of yeast cells. The biomolecules derived from the secretion of yeast cells are used as conditioning and stabilizing agents to control the biosynthesis of the HPCaCO3/CaF2 materials, which exhibit excellent water dispersibility and favorable biocompatibility. The double‐shelled CaCO3/CaF2 nanospheres hold hierarchically porous structure and have abundant pore channel and large specific surface area, showing high drug‐loading and a prolonged drug sustainable release profile by the pore‐by‐pore diffusion pattern of the hierarchical pores. Otherwise, the HPCaCO3 with pH‐sensitivity could controllably release drug doxorubicin hydrochloride (DOX) at the acidic tumor microenvironment. Both in vitro and in vivo results demonstrate that HPCaCO3/CaF2 has the sustainable pH‐sensitive drug release property, showing an enhanced therapeutic effect. Summarily, this study provides a biomimetic strategy to synthesize the hierarchically porous double‐shelled hollow nanomaterials for applying in sustainable drug delivery system. [ABSTRACT FROM AUTHOR]

In this Synpacts article, we describe the concept of cyclodimerization in the biosynthesis and biomimetic synthesis of natural products and unnatural products. We also discuss key details of our discovery and development of a biomimetic-like, selective, homo- and heterochiral cyclodimerization strategy for the construction of nonnatural dimeric carbazole frameworks by employing a formal [3+2] annulation. Our work also demonstrated a novel reactivity of 1-(indol-2-yl)pent-4-yn-3-ols, and their potential as new synthetic building blocks in organic synthesis. 1 Introduction: Chiral Cyclodimerization Reactions 2 Biomimetic Syntheses of Natural Products through Chiral Cyclodimerizations 3 Bioinspired Synthesis of Nonnatural Dimeric Carbazoles through Selective Chiral Cyclodimerizations 4 Future Perspectives and Conclusions [ABSTRACT FROM AUTHOR]

Simulated body fluid (SBF) and artificial saliva (AS) are used in biomedical and dental research to mimic the physiological conditions of the human body. In this study, the biomimetic precipitation of double-doped amorphous calcium phosphate in SBF and AS are compared by thermodynamic modelling of chemical equilibrium in the SBF/AS-CaCl2-MgCl2-ZnCl2-K2HPO4-H2O and SBF/AS-CaCl2-MgCl2-ZnCl2-K2HPO4-Glycine/Valine-H2O systems. The saturation indices (SIs) of possible precipitate solid phases at pH 6.5, close to pH of AS, pH 7.5, close to pH of SBF, and pH 8.5, chosen by us based on our previous experimental data, were calculated. The results show possible precipitation of the same salts with almost equal SIs in the two biomimetic environments at the studied pHs. A decrease in the saturation indices of magnesium and zinc phosphates in the presence of glycine is a prerequisite for reducing their concentrations in the precipitates. Experimental studies confirmed the thermodynamic predictions. Only X-ray amorphous calcium phosphate with incorporated Mg (5.86–8.85 mol%) and Zn (0.71–2.84 mol%) was obtained in the experimental studies, irrespective of biomimetic media and synthesis route. Solid-state nuclear magnetic resonance (NMR) analysis showed that the synthesis route affects the degree of structural disorder of the precipitates. The lowest concentration of dopant ions was obtained in the presence of glycine. Further, the behaviour of the selected amorphous phase in artificial saliva was studied. The dynamic of Ca2+, Mg2+, and Zn2+ ions between the solid and liquid phases was monitored. Both direct excitation 31P NMR spectra and 1H-31P CP-MAS spectra proved the increase in the nanocrystalline hydroxyapatite phase upon increasing the incubation time in AS, which is more pronounced in samples with lower additives. The effect of the initial concentration of doped ions on the solid phase transformation was assessed by solid-state NMR. [ABSTRACT FROM AUTHOR]

Herein, we report our investigations on the biomimetic bromofunctionalization of aromatic and heteroaromatic compounds using NaBr as a source of bromine, 30% (w/v) H2O2 as an oxidant, and SeCl4 as a commercially available catalyst in water without a co-solvent. Under these mild conditions, brominated (hetero)aromatic compounds were obtained in reasonable yields. In addition, 77Se NMR experiments were performed to provide experimental support for the proposed mechanism of the developed halofunctionalization reaction. [ABSTRACT FROM AUTHOR]

The silicifying peptide R5 (H‐SSKKSGSYSGSKGSKRRIL‐OH) derived from diatoms is extensively investigated, but the mechanism underlying silica synthesis by R5 or R5‐alike peptides is still poorly understood, limiting the design of silicifying peptides Herein, machine learning techniques are used to design peptides with silicifying functionality. Utilizing a comprehensive dataset of peptides and their corresponding silicification outcomes, a deep learning model based on antimicrobial peptide migration learning is created. This model exhibits the remarkable capability to accurately predict peptide sequences with a high potential for facilitating silica formation. A selection of artificially designed peptides can catalyze the biomimetic synthesis of nanosilica, some of which demonstrate better catalytic activity with a wider pH range and faster reaction rate compared with the peptide R5. Additionally, the designed peptide is used to wrap the model diatom Phaeodactylum tricornutum with nanosilica coatings, resulting in a significant enhancement in the UV resistance of cells. The new silicified peptides are highly significant for advancing the understanding of the silica synthesis mechanism in diatoms, and the encapsulation of P. tricornutum has potential benefits in the development of new biosensors. [ABSTRACT FROM AUTHOR]

A pair of coumarin-based polycyclic meroterpenoid enantiomers (+)/(−)-gerbeloid A [(+)-1a and (−)-1b] were isolated from the medicinal plant Gerbera piloselloides, which have a unique caged oxatricyclo [4.2.2.03,8] decene scaffold. Their planar and three-dimensional structures were exhaustively characterized by comprehensive spectroscopic data and X-ray diffraction analysis. Guided by the hypothetical biosynthetic pathway, the biomimetic synthesis of racemic 1 was achieved using 4-hydroxy-5-methylcoumarin and citral as the starting material via oxa-6π electrocyclization and intramolecular [2 + 2] photocycloaddition. Subsequently, the results of the biological activity assay demonstrated that both (+)-1a and (−)-1b exhibited potent lipid-lowering effects in 3T3-L1 adipocytes and the high-fat diet zebrafish model. Notably, the lipid-lowering activity of (+)-1a is better than that of (−)-1b at the same concentration, and molecular mechanism study has shown that (+)-1a and (−)-1b impairs adipocyte differentiation and stimulate lipolysis by regulating C/EBPα/PPARγ signaling and Perilipin signaling in vitro and in vivo. Our findings provide a promising drug model molecule for the treatment of obesity.

Marine ladder polyethers have attracted the attention of chemists and biologists because of their potent biological activities. Synthetic chemists have attempted to construct their polyether frameworks by epoxide ring‐opening cascades, as Nakanishi hypothesis describes. However, Baldwin's rules of ring closure state that exo‐selective intramolecular cyclization of epoxy alcohols is preferred over endo‐selective cyclization. Herein, we investigated epoxide ring‐opening cascades of polyepoxy alcohols in [EMIM]BF4/PFTB (1‐ethyl‐3‐methylimidazolium tetrafluoroborate /perfluoro‐tert‐butyl alcohol) and found that all‐endo products were formed via epoxide‐to‐epoxonium ring‐opening cyclizations (not restricted by Baldwin's rules, which only apply to intramolecular hydroxyl‐to‐epoxide cyclizations). We determined that the key factor enabling polyepoxy alcohols to undergo a high proportion of all‐endo‐selective cyclization was inhibition of exo‐selective hydroxyl‐to‐epoxide cyclization starting from the terminal hydroxyl group of a polyepoxy alcohol. By introducing a slow‐release protecting group to the terminal hydroxyl group, we could markedly increase the cyclization yields of polyether fragments with hydrogen atoms at the ring junctions. For the first time, we constructed consecutively fused six‐membered‐ring and fused seven‐, eight‐, and nine‐membered‐ring polyether fragments by epoxide‐to‐epoxonium ring‐opening cyclizations through the addition of a suitable Lewis acid. We also suggest that the biosynthesis of marine ladder polyethers may proceed via epoxide‐to‐epoxonium ring‐opening cyclization of polyepoxide. [ABSTRACT FROM AUTHOR]

Biologically mediated synthesis of nanomaterials has emerged as an ecologically benign and biocompatible approach. Our study explores enzymatic synthesis, utilizing α-amylase to synthesize ZnO nanoflowers (ZnO-NFs). X-ray diffraction and energy-dispersive X-ray spectroscopy revealed crystal structure and elemental composition. Dynamic light scattering analysis indicates that ZnO-NFs possess a size of 101 nm. Transmission electron microscopy showed a star-shaped morphology of ZnO-NFs with petal-like structures. ZnO-NFs exhibit potent photocatalytic properties, degrading 90% eosin, 87% methylene blue, and 81% reactive red dyes under UV light, with kinetics fitting the Langmuir–Hinshelwood pseudo-first-order rate law. The impact of pH and interfering substances on dye degradation was explored. ZnO-NFs display efficient bacteriocidal activity against different Gram-positive and negative strains, antibiofilm potential (especially with P. aeruginosa), and hemocompatibility up to 600 ppm, suggesting versatile potential in healthcare and environmental remediation applications. [ABSTRACT FROM AUTHOR]

Vesicle, a microscopic unit that encloses a volume with an ultrathin wall, is ubiquitous in biomaterials. However, it remains a huge challenge to create its inorganic metal-based artificial counterparts. Here, inspired by the formation of biological vesicles, we proposed a novel biomimetic strategy of curling the ultrathin nanosheets into nanovesicles, which was driven by the interfacial strain. Trapped by the interfacial strain between the initially formed substrate Rh layer and subsequently formed RhRu overlayer, the nanosheet begins to deform in order to release a certain amount of strain. Density functional theory (DFT) calculations reveal that the Ru atoms make the curling of nanosheets more favorable in thermodynamics applications. Owing to the unique vesicular structure, the RhRu nanovesicles/C displays excellent hydrogen oxidation reaction (HOR) activity and stability, which has been proven by both experiments and DFT calculations. Specifically, the HOR mass activity of RhRu nanovesicles/C are 7.52 A mg(Rh+Ru)−1 at an overpotential of 50 mV at the rotating disk electrode (RDE) level; this is 24.19 times that of commercial Pt/C (0.31 mA mgPt−1). Moreover, the hydroxide exchange membrane fuel cell (HEMFC) with RhRu nanovesicles/C displays a peak power density of 1.62 W cm−2 in the H2-O2 condition, much better than that of commercial Pt/C (1.18 W cm−2). This work creates a new biomimetic strategy to synthesize inorganic nanomaterials, paving a pathway for designing catalytic reactors. [ABSTRACT FROM AUTHOR]

Background: In recent years, ellagic acid has emerged as a focal point in pharmacological research, showcasing promising developments and potential therapeutic applications as a competitive inhibitor of Src homology phosphotyrosyl phosphatase 2 for the treatment of cancer, as a shielding impact that stimulates sirtuin 6 (SIRT 6), against nephrotoxicity induced by cisplatin, as adjuvant treatment in sickle cell anemia, as antiaging and to avoid mild cognitive impairment. Purpose: This review provides a concise overview of the latest advancements in ellagic acid research, highlighting novel pharmacological findings and emerging trends. Methodology: A comprehensive search of relevant literature was conducted to gather information on the pharmacological properties and therapeutic applications of ellagic acid. Studies investigating its antioxidant properties, anti-inflammatory effects, molecular interactions, and therapeutic implications were included in the analysis. Results: The review summarizes the multifaceted pharmacological landscape of ellagic acid, encompassing its antioxidant properties, anti-inflammatory effects, and potential therapeutic applications. It sheds light on its evolving role in modern medicine and underscores its significance as a promising avenue for future pharmaceutical exploration. Conclusion: The recent strides in ellagic acid development highlight its potential as a valuable therapeutic agent in various health conditions. Further research into its molecular interactions and clinical applications is warranted to fully harness its therapeutic potential and improve patient outcomes. [ABSTRACT FROM AUTHOR]

A pair of coumarin-based polycyclic meroterpenoid enantiomers (+)/(−)-gerbeloid A [(+)- 1a and (−)- 1b ] were isolated from the medicinal plant Gerbera piloselloides , which have a unique caged oxatricyclo [4.2.2.03,8] decene scaffold. Their planar and three-dimensional structures were exhaustively characterized by comprehensive spectroscopic data and X-ray diffraction analysis. Guided by the hypothetical biosynthetic pathway, the biomimetic synthesis of racemic 1 was achieved using 4-hydroxy-5-methylcoumarin and citral as the starting material via oxa-6 π electrocyclization and intramolecular [2 + 2] photocycloaddition. Subsequently, the results of the biological activity assay demonstrated that both (+)- 1a and (−)- 1b exhibited potent lipid-lowering effects in 3T3-L1 adipocytes and the high-fat diet zebrafish model. Notably, the lipid-lowering activity of (+)- 1a is better than that of (−)- 1b at the same concentration, and molecular mechanism study has shown that (+)- 1a and (−)- 1b impairs adipocyte differentiation and stimulate lipolysis by regulating C/EBP α /PPAR γ signaling and Perilipin signaling in vitro and in vivo. Our findings provide a promising drug model molecule for the treatment of obesity. A pair of unique caged coumarin-meroterpenoid enantiomers (+)/(−)-gerbeloid A were discovered from Gerbera piloselloides and synthesized biomimetically. (+)- 1a and (−)- 1b showed potent lipid-lowering activities in vitro and in vivo. [Display omitted] [ABSTRACT FROM AUTHOR]

A new dimeric C-glycoside polyketide chrysomycin F (1), along with four new monomeric compounds, chrysomycins G (2), H (3), I (4), J (5), as well as three known analogues, chrysomycins A (6), B (7), and C (8), were isolated and characterised from a strain of Streptomyces sp. obtained from a sediment sample collected from the South China Sea. Their structures were determined by detailed spectroscopic analysis. Chrysomycin F contains two diastereomers, whose structures were further elucidated by a biomimetic [2 + 2] photodimerisation of chrysomycin A. Chrysomycins B and C showed potent anti-tuberculosis activity against both wild-type Mycobacterium tuberculosis and a number of clinically isolated MDR M. tuberculosis strains. [ABSTRACT FROM AUTHOR]

In this study, TiO2/P, K-containing grapefruit peel biochar (TiO2/P, K-PC) composites were synthesized in situ biomimetically using grapefruit peel as the bio-template and carbon source and tetrabutyl titanate as the titanium source. This was achieved using the two-step rotary impregnation–calcination method. Adjusting the calcination temperature of the sample in an air atmosphere could regulate the mass ratio of TiO2 to carbon. The prepared samples were subjected to an analysis of their compositions, structures, morphologies, and properties. It demonstrated that the prepared samples were complexes of anatase TiO2 and P, K-containing carbon, with the presence of graphitic carbon. They possessed a unique morphological structure with abundant pores and a large surface area. The grapefruit peel powder played a crucial role in the induction and assembly of TiO2/P, K-PC composites. The sample PCT-400-550 had the best photocatalytic activity, with the degradation rate of RhB, MO, and MB dye solutions reaching more than 99% within 30 min, with satisfactory cyclic stability. The outstanding photocatalytic activity can be credited to its unique morphology and the efficient collaboration between TiO2 and P, K-containing biochar. [ABSTRACT FROM AUTHOR]

Abstract Biomineralization is the intricate process by which living organisms orchestrate the formation of organic–inorganic composites by regulating the nucleation, orientation, growth, and assembly of inorganic minerals. As our comprehension of biomineralization principles deepens, novel strategies for fabricating inorganic materials based on these principles have emerged. Researchers can also harness biomineralization strategies to tackle challenges in both materials' science and biomedical fields, demonstrating a thriving research field. This review begins by introducing the concept of biomineralization and subsequently shifts its focus to a recently discovered chemical concept: inorganic ionic oligomers and their cross‐linking. As a novel approach for constructing inorganic materials, the inorganic ionic oligomer‐based strategy finds applications in biomimetic regeneration and repair of hard tissues, such as teeth and bones. Aside from innovative methods for material fabrication, biomineralization has emerged as an alternative method for tackling biomedical challenges by integrating materials with biological organisms, facilitating advancements in biomedical fields. Emerging material‐biological integrators play a critical role in areas like vaccine improvement, cancer therapy, universal blood transfusion, and arthritis treatment. This review highlights the profound impact of biomineralization in the development and design of high‐performance materials that go beyond traditional disciplinary boundaries, potentially promoting breakthroughs in materials science, chemical biology, biomedical, and numerous other domains.

This work reports a biomimetic synthesis of polyarylated fluorene derivatives. The molecules are formed via intramolecular electrophilic aromatic substitution, resembling a cyclization leading towards the natural selaginpulvilins from selaginellins. The scope of the reaction was investigated, and the products were obtained in 60–95 % yields. Some of the compounds decompose to a stable radical. We investigated the nature and the origin of the radical using experimental methods, including EPR or electrochemical measurements, as well as theoretical methods, such as DFT calculations. Based on our observations, we hypothesize, that phenoxy radicals are formed in the first instance, which however undergo internal rearrangement to thermodynamically more stable carbon‐centered radicals. The preliminary data also show the cytotoxic properties of some of the molecules. [ABSTRACT FROM AUTHOR]

The copper nanoparticles (Cu-NPs), through a novel green synthesis method utilizing Tinospora Cordifolia (TC) aqueous leaf extract as a reducing and stabilizing agent, were synthesized, and investigated for their dye degradation potential. The bio-synthesis process, which is operationally simple, non-toxic, and cost-effective, involves using cupric oxide (CuO) as precursor material. The degradation of dyes in water bodies is challenging research due to their stable nature; therefore, it is essential to develop potential catalyst materials with desirable properties to degrade dyes in water bodies. The CuNPs were characterized using X-ray diffraction (XRD), UV–Vis spectrometer, scanning electron microscopy (SEM), and a Fourier transformed infrared spectrometer (FTIR). The FTIR results confirmed the presence of phytochemicals involved in the reduction, capping, and stabilization of CuNPs, which was corroborated by the XRD data. The photo-catalytic activity of biosynthetic CuNPs was studied using methylene blue (MB) dye upon exposure to visible light source irradiation. The results showed that bio-synthesized CuNPs exhibited a high potential for dye degradation for the methylene blue dye in the presence of a visible light source and a dye degradation rate of 81% was achieved. The green-synthesized CuNPs have proven to be a potential candidate for efficiently removing dyes from water bodies and provide a sustainable, environmentally friendly method for producing metal nanoparticles with excellent photo-catalytic properties. [ABSTRACT FROM AUTHOR]

This article explores the use of computational chemistry in studying the feasibility of biomimetic syntheses of polycyclic furanocembrane derivatives. The authors emphasize the significance of natural products, particularly marine natural products, in pharmaceutical research due to their unique structures and diverse biological activities. Biomimetic synthesis, which involves creating complex molecules from simple natural precursors, is an effective method for synthesizing natural products. Quantum chemical calculations are employed to analyze proposed biosynthetic reactions and design optimal reaction pathways. The article provides an overview of the computational methodology used in these studies and presents specific examples of polycyclic furanocembrane derivatives and their proposed biomimetic syntheses. The authors stress the importance of computational studies in assessing the reliability of these proposed connections and how they can assist synthetic chemists in developing biomimetic synthesis pathways. The article concludes by highlighting the continued interest in utilizing computational chemistry for natural product synthesis. [Extracted from the article]

This article explores the synthesis and characterization of chejuenolides, a group of natural products with potential medicinal applications. The authors conducted total synthesis of chejuenolide C and identified it in a newly discovered strain of bacteria. They also investigated the stereochemistry involved in the macrocyclization process and found that the configuration at C13 has a significant impact on the stereochemistry of the product. The authors hope that their research will inspire further studies in biomimetic synthesis. [Extracted from the article]

This article discusses the total synthesis of dysidavarones A-C, which are sesquiterpene quinones isolated from the sponge Dysidea avara. These compounds have a unique carbon skeleton and exhibit bioactivity against cancer cell lines and bacteria. Several synthetic routes have been developed to produce these compounds, but they have limitations in terms of yield and purification. The authors present a practical and scalable synthesis method that overcomes these challenges and provides sufficient quantities of dysidavarones for further research. [Extracted from the article]

This article, published in the journal Synlett, explores the use of biomimetic dimerization in the synthesis of natural products. The authors discuss the efficiency and elegance of this approach and its popularity in the field. They present two case studies, focusing on the synthesis of linderaspirone A and bi-linderone, as well as parvistemin A and (±)-diperezone. The authors propose biosynthetic pathways and synthetic approaches for these compounds. They also discuss the use of biomimetic dimerization in the total synthesis of other natural products, such as scabellone B and spiroxins A/C/D. The article acknowledges the contributions of the research group members and provides brief biographies of the authors. [Extracted from the article]

Pollen grains, with their resilient sporopollenin exine and defined morphologies, have been explored as bio-templates for the synthesis of calcium phosphate minerals, particularly hydroxyapatite (HAp) and β-tricalcium phosphate (TCP). Various pollen morphologies from different plant species (black alder, dandelion, lamb's quarters, ragweed, and stargazer lily) were evaluated. Pollen grains underwent acid washing to remove allergenic material and facilitate subsequent calcification. Ragweed and lamb's quarter pollen grains were chosen as templates for calcium phosphate salts deposition due to their distinct morphologies. The calcification process yielded well-defined spherical hollow particles. The washing step, intended to reduce the protein content, did not significantly affect the final product; thus, justifying the removal of this low-yield step from the synthesis process. Characterisation techniques, including X-ray diffraction, scanning electron microscopy, Fourier-transform infrared spectroscopy, and thermal gravimetric analysis, confirmed the successful calcification of pollen-derived materials, revealing that calcified grains were principally composed of calcium deficient HAp. After calcination, biphasic calcium phosphate composed of HAp and TPC was obtained. This study demonstrated the feasibility of using pollen grains as green and sustainable bio-templates for synthesizing biomaterials with controlled morphology, showcasing their potential in biomedical applications such as drug delivery and bone regeneration. [ABSTRACT FROM AUTHOR]

Hybrid materials based on calcium phosphates and synthetic polymers can potentially be used for caries protection due to their similarity to hard tissues in terms of composition, structure and a number of properties. This study is focused on the biomimetic synthesis of hybrid materials consisting of hydroxiapatite and the zwitterionic polymers polysulfobetaine (PSB) and polycarboxybetaine (PCB) using controlled media conditions with a constant pH of 8.0–8.2 and Ca/P = 1.67. The results show that pH control is a dominant factor in the crystal phase formation, so nano-crystalline hydroxyapatite with a Ca/P ratio of 1.63–1.71 was observed as the mineral phase in all the materials prepared. The final polymer content measured for the synthesized hybrid materials was 48–52%. The polymer type affects the final microstructure, and the mineral particle size is thinner and smaller in the synthesis performed using PCB than using PSB. The final intermolecular interaction of the nano-crystallized hydroxyapatite was demonstrated to be stronger with PCB than with PSB as shown by our IR and Raman spectroscopy analyses. The higher remineralization potential of the PCB-containing synthesized material was demonstrated by in vitro testing using artificial saliva. [ABSTRACT FROM AUTHOR]

BACKGROUND: Phytopathogens cause various diseases by parasitizing crops, reducing crop yield and resulting in substantial economic losses in agricultural production. A novel type isolated from the perennial herbaceous Peganum harmala L. seeds, β‐carboline alkaloids pegaharine A (PA), has become a hot topic in developing plant‐originated green pesticides owing to their significant physiological activities. RESULTS: A scalable bioinspired total synthesis of PA is accomplished in the present work. The systematical biological assay study showed that PA exhibited moderate inhibitory activity against nine tested plant pathogenic fungi and showed significant inhibitory activity in vitro against the three tested plant pathogenic bacteria. Most noteworthy is the inhibitory rates of PA on Xanthomonas oryzae pv. oryzae (Xoo), X. oryzae pv. oryzicola (Xoc) and X. axonopodis pv. citri (Xac) of 93.6%, 92.1% and 86.1%, respectively, which are better than the control drug, bismerthiazol (63.4%, 61.2% and 53.7% at 100 μg mL−1 concentration). Furthermore, the EC50 value of PA against Xoo, Xoc and Xac was 52.2, 60.0 and 65.1 μg mL−1, respectively, superior to 72.9, 64.2 and 70.1 μg mL−1 of the control drug. Moreover, the anti‐Xoo mechanistic studies revealed that PA exerted its antibacterial effects by increasing the permeability of the bacterial membrane, reducing the extracellular polysaccharide content and inducing morphological changes in bacterial cells. CONCLUSION: A novel β‐carboline alkaloid, PA, was prepared by biomimetic total synthesis. Its significant antibacterial activity was closely related to the permeation of bacterial cell membranes, which was confirmed by anti‐Xoo mechanistic studies. More importantly, the structure could be regarded as a model for developing novel bactericides. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Nano CaCO3 (nC), various polymer mediated nano CaCO3 and Eu3+ anchored nano CaCO3/PEG were synthesized from natural carbonate source (Dolomite) (CaMg(CO3)2) using a novel, low cost, non-toxic and effective route biomimetic synthesis. The mineralogy, structural, thermal stability, and morphology analysis of the products were assessed through FTIR, XRD, TG-DTA, FE-SEM with EDX mapping, and HR-TEM with SAED. Results show that the prepared samples were in the form of calcite with rhombohedral (25-36 nm) structure. The prepared products exhibit good thermal stability up to 844° C. The products show a spherical and porous like structure. The elemental compositions of the products were confirmed through EDX analysis. All the plane values (observed from SAED) were matched with XRD results. An increase of Eu3+ in CaCO3 shows that the absorption and emission peaks are blue shifted and the band gap values are red shifted. The measured photoluminescence quantum yield values of 0.02 Eu3+:CaCO3/PEG (nCE1) and 0.08 Eu3+: CaCO3/PEG (nCE4) are 21% and 19%, respectively. Finally, the products (nC, nCE1, and nCE4) were subjected to photodegradation application and results shows that nCE1 has good photocatalytic activity against methylene blue (87%) for 90 min. [ABSTRACT FROM AUTHOR]

We report asymmetric bioinspired total syntheses of the fungal metabolites emeriones A-C via stereoselective oxidations of two bicyclo[4.2.0]octadiene diastereomers. The central bicyclic scaffolds are prepared in an 8π/6π electrocyclization cascade of a stereodefined pentaene, which contains the fully assembled side chains of the emeriones. The anti-aldol side chain is made using a Paterson-aldol addition, and the epoxide of the dioxabicyclo[3.1.0]hexane side chain via ring-closure onto an oxidized acetal. Our work has enabled the structural revision of emerione C, and resulted in the synthesis of a "missing" family member, which we call emerione D. DFT calculations identified two methyl groups that govern torquoselectivity in the 8π/6π cascade.

The microstructure of bone consists of nano-hydroxyapatite (nano-HA) crystals aligned within the interspaces of collagen fibrils. To emulate this unique microstructure of bone, this work applied two biomimetic techniques to obtain bone-like microstructures in vitro, that is, combining the construction of collagen liquid crystal hydrogel (CLCH) with the application of a polymer-induced liquid precursor (PILP) mineralization process. Upon the elevation of pH, the collagen macromolecules within the collagen liquid crystal (CLC) were activated to self-assemble into CLCH, whose fibrils packed into a long and dense fiber bundle in high orientation, emulating the dense-packed matrix of bone. We demonstrated that the fibrillar mineralization of CLCH, leading to a bone-like nanostructured inorganic material part, can be achieved using the PILP crystallization process to pre-mineralize the dense collagen substrates of CLCH with CaCO3, immediately followed by the in situ mineral phase transformation of CaCO3 into weak-crystalline nano-HA. The combination of CLCH with the biomineralization process of PILP, together with the mineral phase transformation, achieved the in vitro simulation of the nanostructures of both the organic extracellular matrix (ECM) and inorganic ECM of bone. This design would constitute a novel idea for the design of three-dimension biomimetic bone-like material blocks for clinical needs.

Herein we report the first enantioselective total synthesis of (+)‐incargranine A, in nine steps. The total synthesis was enabled by an enantioselective intramolecular organocatalysed desymmetrising Michael addition of a malonamate ester to a linked dienone substrate that established pivotal stereocentres with excellent enantio‐ and complete diastereoselectivity. Furthermore, a key hemiaminal intermediate was accessed by developing an iridium‐catalysed reductive cyclisation, and the scope of this transformation was explored to produce a range of bicyclic hemiaminal motifs. Once installed, the hemiaminal motif was used to initiate a biomimetic cascade to access the natural product directly in a single step. [ABSTRACT FROM AUTHOR]

Biosilica, synthesized annually only by diatoms, is almost 1000 times more abundant than industrial silica. Biosilicification occurs at a high rate, although the concentration of silicic acid in natural waters is ~100 μM. It occurs in neutral aqueous solutions, at ambient temperature, and under the control of proteins that determine the formation of hierarchically organized structures. Using diatoms as an example, the fundamental differences between biosilicification and traditional sol–gel technology, which is performed with the addition of acid/alkali, organic solvents and heating, have been identified. The conditions are harsh for the biomaterial, as they cause protein denaturation and cell death. Numerous attempts are being made to bring sol–gel technology closer to biomineralization processes. Biomimetic synthesis must be conducted at physiological pH, room temperature, and without the addition of organic solvents. To date, significant progress has been made in approaching these requirements. The review presents a critical analysis of the approaches proposed to date for the silicification of biomacromolecules and cells, the formation of bionanocomposites with controlled structure, porosity, and functionality determined by the biomaterial. They demonstrated the broad capabilities and prospects of biomimetic methods for creating optical and photonic materials, adsorbents, catalysts and biocatalysts, sensors and biosensors, and biomaterials for biomedicine. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Adhesive hydrogels are an emerging class of hydrogels that combine three‐dimensional hydrated networks with adhesive properties. These properties facilitate intimate tissue‐material contact in diverse biomedical applications, enhancing tissue joining, drug transport, and signal transmission. Inspired by the universal adhesiveness of mussel foot proteins, 3,4‐dihydroxyphenyl‐L‐alanine (DOPA) and its analogs have been extensively exploited for the fabrication of adhesive hydrogels, within which the DOPA moieties can not only serve as cross‐linking mediators but also participate in various intermolecular and surface interactions to mediate wet adhesion. This mini‐review highlights recent achievements in the development of mussel‐inspired adhesive hydrogels, focusing on: (1) elucidating DOPA‐mediated adhesion mechanisms through nanomechanical characterizations, (2) designing injectable adhesive hydrogels toward applications in drug delivery, hemostasis, and wound closure, which includes in situ gelling liquids and shear‐thinning preformed hydrogels, and (3) fabricating tough adhesive hydrogels with enhanced mechanical properties for use in tissue regeneration, biosensing, and bioimaging, with typical examples of nanocomposite and double‐network hydrogels. The challenges and prospects in this rapidly developing field are also discussed. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Adhesive hydrogels are an emerging class of hydrogels that combine three‐dimensional hydrated networks with adhesive properties. These properties facilitate intimate tissue‐material contact in diverse biomedical applications, enhancing tissue joining, drug transport, and signal transmission. Inspired by the universal adhesiveness of mussel foot proteins, 3,4‐dihydroxyphenyl‐L‐alanine (DOPA) and its analogs have been extensively exploited for the fabrication of adhesive hydrogels, within which the DOPA moieties can not only serve as cross‐linking mediators but also participate in various intermolecular and surface interactions to mediate wet adhesion. This mini‐review highlights recent achievements in the development of mussel‐inspired adhesive hydrogels, focusing on: (1) elucidating DOPA‐mediated adhesion mechanisms through nanomechanical characterizations, (2) designing injectable adhesive hydrogels toward applications in drug delivery, hemostasis, and wound closure, which includes in situ gelling liquids and shear‐thinning preformed hydrogels, and (3) fabricating tough adhesive hydrogels with enhanced mechanical properties for use in tissue regeneration, biosensing, and bioimaging, with typical examples of nanocomposite and double‐network hydrogels. The challenges and prospects in this rapidly developing field are also discussed. [ABSTRACT FROM AUTHOR]

A synthetic strategy based on biogenetic building blocks for the collective and divergent biomimetic synthesis of cleistoperlones A−F, a cinnamoylphloroglucinol collection discovered from Cleistocalyx operculatus, has been developed. These syntheses proceeded successfully in only six to seven steps starting from commercially available 1,3,5‐benzenetriol and involving oxidative activation of stable biogenetic building blocks as a crucial step. Key features of the syntheses include a unique Michael addition/ketalization/1,6‐addition/enol‐keto tautomerism cascade reaction for the construction of the dihydropyrano[3,2‐d]xanthene tetracyclic core of cleistoperlones A and B, and a rare inverse‐electron‐demand hetero‐Diels–Alder cycloaddition for the establishment of benzopyran ring in cleistoperlones D−F. Moreover, cleistoperlone A exhibited significant antiviral activity against acyclovir‐resistant strains of herpes simplex virus type 1 (HSV‐1/Blue and HSV‐1/153). [ABSTRACT FROM AUTHOR]

Photothermal therapy (PTT) combined with chemodynamic therapy (CDT) presents an appealing complementary anti-tumor strategy, wherein PTT accelerates the production of reactive oxygen species (ROS) in CDT and CDT eliminates residual tumor tissues that survive from PTT treatment. However, nanomaterials utilized in PTT/CDT are limited by non-specific damage to the entire organism. Herein, a glucose-responsive enzymatic Fe@HRP-ABTS/GOx nanodot is judiciously designed for tumor-specific PTT/CDT via a simple and clean protein-templated biomimetic mineralization synthesis. By oxidizing glucose in tumor cells, glucose oxidase (GOx) activates glucose-responsive tumor therapy and increases the concentration of H 2 O 2 at the tumor site. More importantly, the self-supplied peroxide hydrogen (H 2 O 2) can convert ABTS (2,2′-Hydrazine-bis(3-ethylbenzothiazoline-6-sulfonic acid) diamine salt) into oxidized ABTS (oxABTS) through horseradish peroxidase (HRP) catalysis for PTT and photoacoustic (PA) imaging. Furthermore, the Fe2+ arising from the reduction of Fe3+ by overexpressed GSH reacts with H 2 O 2 to generate intensely reactive •OH through the Fenton reaction, concurrently depleting GSH and inducing efficient tumor CDT. The in vitro and in vivo experiments demonstrate superior cancer cell killing and tumor eradication effect of Fe@HRP-ABTS/GOx nanodot under near-infrared (NIR) laser irradiation. Collectively, the nanodots provide mutually reinforcing catalytic PTT/CDT anti-tumor strategies for treating liver cancer and potentially other malignancies. Combinatorial antitumor therapy with nanomedicines presents great prospects for development. However, the limitation of non-specific damage to normal tissues hinders its further clinical application. In this work, we fabricated tumor-selective biomimetic Fe@HRP-ABTS/GOx nanodots for H 2 O 2 self-supplied catalytic photothermal/chemodynamic therapy of tumors. The biomimetic synthesis strategy provides the nanodots with enzymatic activity in response to glucose to produce H 2 O 2. The self-supplied H 2 O 2 initiates photothermal therapy with oxidized ABTS and enhances chemodynamic therapy through simultaneous •OH generation and GSH depletion. Our work provides a new paradigm for developing tumor-selective catalytic nanomedicines and will guide further clinical translation of the enzymatic biomimetic synthesis strategy. [Display omitted] [ABSTRACT FROM AUTHOR]

Autocatalytic reactions were proposed to play a key role at the beginning of life starting from the first reduction of CO2 to formate, acetate and C1−C4 hydrocarbons. In carbon capture and utilization (CCU) processes, the same reactions were demonstrated to be autocatalytic and, in some cases, promoted by catalysts of the same composition. Through evolution, CO2 reduction then turned into complex autocatalytic networks such as photosynthesis, where CCU chemists found inspiration for the development of more advanced systems for the synthesis of value‐added chemicals. Less evolved systems than photosynthesis, however, may be easier to emulate and provide valuable inspiration into CO2 reduction chemistry for CCU. Other synthetic systems were also demonstrated to be autocatalytic demonstrating that CO2 reactions and autocatalysis are closely connected. In this concept article, the relationship between natural, artificial and bio‐inspired autocatalytic CO2 reduction processes is summarized and discussed. The accomplishments resulting from the integration of autocatalysis and CCU strategies, along with their inherent benefits and future prospectives are also outlined. [ABSTRACT FROM AUTHOR]

A novel and efficient mesoporous nano-absorbent for U(VI) removal was developed through an environment-friendly route by inducing the biomimetic mineralization of hydroxyapatite (HAP) on the bioinspired surface of polydopamine-graphene oxide (PDA-GO). PDA-GO/HAP exhibited the greatly rapid and efficient U(VI) removal within 2 min, and much higher U(VI) adsorption capacity of 433.07 mg·g−1 than that of GO and PDA-GO. The enhanced adsorption capacity was mainly attributed to the synergistic effect of O–H, –C=N–, and PO43− functional groups and the incorporation of uranyl ions by the formation of a new phase (chernikovite, H2(UO2)2(PO4)2·8H2O). The adsorption process of U(VI) fitted well with pseudo-second-order kinetic and Langmuir isotherm model. Moreover, PDA-GO/HAP showed a high U(VI) adsorption capacity in a broad range of pH values and owned good thermal stability. PDA-GO/HAP with various excellent properties made it a greatly promising adsorbent for extracting uranium. Our work developed a good strategy for constructing fast and efficient uranium-adsorptive biomimetic materials. [ABSTRACT FROM AUTHOR]

Organisms use gene and cell engineering to tailor the mineralization process and synthesize structure composites with special functions and favorable properties. This spurs scientists to design functional materials based on learning from nature. Herein, a systematic review of the biomimetic synthesis and hierarchical structure design of calcium carbonate–based minerals is presented. First, biomimetic synthesis strategies, including additive‐induced, template‐oriented, and gel‐mediated routes to direct the construction of the hierarchical structure, are reviewed. The molecular‐recognition technique and directional assembly pathway are then summarized to precisely describe the interactions between inorganic minerals and organic matter, and direct the mineral growth. Next, the underlying mineralization mechanisms governing the evolution of the complex morphology and structure are discussed. Nonclassical pathways that control mineral growth, including the theories of the amorphous phase, oriented attachment, mesocrystal formation, and liquid precursor, are concluded. Finally, herein, the applications of calcium carbonate–based minerals are discussed. Unique hierarchical structure endows minerals with special functions, including optical performance, biomedical applications, and environmental and ecological restoration. Overall, in this report, the biomimetic synthesis of calcium carbonate–based minerals is reviewed, covering the fundamental principles, construction of the hierarchical structure, underlying mechanisms of mineral growth, and functional designs. [ABSTRACT FROM AUTHOR]

A new dimeric C-glycoside polyketide chrysomycin F (1), along with four new monomeric compounds, chrysomycins G (2), H (3), I (4), J (5), as well as three known analogues, chrysomycins A (6), B (7), and C (8), were isolated and characterised from a strain of Streptomyces sp. obtained from a sediment sample collected from the South China Sea. Their structures were determined by detailed spectroscopic analysis. Chrysomycin F contains two diastereomers, whose structures were further elucidated by a biomimetic [2 + 2] photodimerisation of chrysomycin A. Chrysomycins B and C showed potent anti-tuberculosis activity against both wild-type Mycobacterium tuberculosis and a number of clinically isolated MDR M. tuberculosis strains.

In this study, TiO2/P, K-containing grapefruit peel biochar (TiO2/P, K-PC) composites were synthesized in situ biomimetically using grapefruit peel as the bio-template and carbon source and tetrabutyl titanate as the titanium source. This was achieved using the two-step rotary impregnation–calcination method. Adjusting the calcination temperature of the sample in an air atmosphere could regulate the mass ratio of TiO2 to carbon. The prepared samples were subjected to an analysis of their compositions, structures, morphologies, and properties. It demonstrated that the prepared samples were complexes of anatase TiO2 and P, K-containing carbon, with the presence of graphitic carbon. They possessed a unique morphological structure with abundant pores and a large surface area. The grapefruit peel powder played a crucial role in the induction and assembly of TiO2/P, K-PC composites. The sample PCT-400-550 had the best photocatalytic activity, with the degradation rate of RhB, MO, and MB dye solutions reaching more than 99% within 30 min, with satisfactory cyclic stability. The outstanding photocatalytic activity can be credited to its unique morphology and the efficient collaboration between TiO2 and P, K-containing biochar.