Gluconate Research Articles

Photocatalytic fenton-like system with atomic Fe on carbon nitride boost selective glucose oxidation towards gluconic acid

Peroxymonosulfate (PMS) activation is a prospective technique for pollutant degradation, but less attention has been paid to the tunable modulation and effective utilization of reactive oxygen species in selective oxidation. Herein, we develop a photocatalytic Fenton-like system with Fe single-atom supported on carbon nitride that generates singlet oxygen (1O2) as dominant active species to selectively oxidize glucose to gluconic acid. The loading of atomic Fe onto carbon nitride can notably aggrandize the light absorption and boost the photon-generated carriers transfer efficiency. With PMS and simulated sunlight, the Fe single-atom catalyst afforded a glucose conversion of 36.3% with gluconic acid selectivity up to 91.6%, as is superior to the state-of-the-art catalytic systems. Control experiments and theoretical analysis reveal that the excellent catalytic performance of Fe single-atom supported on carbon nitride is resulted from the enhanced photocatalytic activity with better PMS activation ability.

Fe3O4 NPs-encapsulated metal-organic framework/enzyme hybrid nanoreactor for drug-resistant bacterial elimination via enhanced chemodynamictherapy

As a potential tool for combating bacterial infections, chemodynamic therapy (CDT), which utilizes the highly toxic hydroxyl radical (•OH), has shown tremendous promise. Its antibacterial efficacy, however, is compromised by insufficient H2O2 levels and a near-neutral pH at infection sites. Herein, a glucose-fueled and H2O2 self-supplying •OH nanogenerator (GOx-Fe3O4@MIL) based on cascade catalytic reactions is successfully constructed by immobilizing glucose oxidase (GOx) on the surface of Fe3O4 NPs-encapsulated MIL88B–NH2. MIL88B–NH2 (MIL NPs), a peroxidase-mimicking enzyme, immobilizes and protects GOx while synergistically enhancing the CDT effect of Fe3O4 NPs. GOx can continuously convert glucose into gluconic acid and H2O2. The former reduces the pH value to approximately 4, at which point Fe3O4@ MIL NPs exhibit the highest reaction activity. The continually produced H2O2 is used for subsequent catalysis of activated Fe3O4 @MIL NPs to generate highly toxic •OH for antibacterial applications, avoiding the direct use of relatively high concentrated and toxic H2O2. In vitro and in vivo results indicate that the designed self-activated nanoreactor can significantly inhibit methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant Acinetobacter baumannii (MDR-AB) growth with negligible biotoxicity.

Bio-metallurgical recovery of lithium, cobalt, and nickel from spent NMC lithium ion batteries: A comparative analysis of organic acid systems

With the increasing demand for lithium-ion batteries, key elements like lithium, graphite, cobalt, and nickel face heightened demand and classification as critical by the European Commission. This study investigates a bio-metallurgical approach for recovering these elements from NMC/C electrode material. The method leverages Aspergillus niger's acid production capacity. Lab experiments involved leaching pyrolyzed black mass using diverse multi-acid systems, including citric, DL-malic, gluconic, and oxalic acid. Parameters such as temperature, leaching time, solid-to-liquid ratio, and molasses as a reductant were varied. Nickel and cobalt recovery rates were modest, with highest rates (13% for Ni, 25.8% for Co) in DL-malic and gluconic acid-rich setups. Maximum lithium recovery (87.9%) occurred in a citric-rich medium. Analysis revealed organo-metallic components in solid residues and formed precipitates, implying oxalic acid's role in inhibiting recovery. Therefore, optimization of acid generation is crucial for effective bio-metallurgical recovery. In summary, this study highlights the potential of Aspergillus niger-mediated bio-metallurgical processes with organic acid mixtures for sustainable recovery of critical elements from spent lithium-ion batteries. The findings contribute crucial insights into optimizing leaching parameters and underscore the significance of bioleaching in addressing the demand for key battery materials. This work has important implications for advancing eco-friendly e-waste recycling practices and aligns with the principles of resource conservation and circular economy in the energy storage sector.

Biomimetic metal organic frameworks mediated by metformin and 1-MT for enhancing the synergistic treatment of photodynamic therapy, photothermal therapy and immunotherapy

Design of novel nanoreactor that integrates multiple therapeutic for tumor remains to be challenging. Here, we developed a multiple antitumor nanoreactor, which consisted of biomimetic Metal Organic Framework (Zn/Co-MOF), metformin, cisplatin, indocyanine Green (ICG), 1-methyl-tryptophan (1-MT) and glucose oxidase (GOD) payload, Mxene and AS1411-aptamer decoration. The constructed Nb2C/aptamer-PDA/GOD@Zn/Co-MOF@M/C (NMC) targeted to the tumor cells via AS1411-aptamer, and magnetic Nb2C/aptamer-PDA/ICG@Zn/Co-MOF@1-MT/C (NTC) targeted to the tumor cells via AS1411-aptamer and magnetic effect. In the acidic tumor microenvironment, NMC can consume endogenous glucose to generate the H2O2 and gluconic acid by GOD-mediated reaction and “starved” the tumors. The abundant of H2O2 is catalyzed to generate the oxygen by the Co and singlet oxygen (1O2) by the ICG, which can improved the hypoxic environment of the tumor and effectively reduced the resistance to PDT. The metformin both can block the glycolytic reaction, causing cell apoptosis and reverse tumor immunosuppression through endoplasmic reticulum related PD-L1 degradation to increase immune response. Simultaneously, metformin can hamper O2 consumption and raise the oxygen content of the tumor site to enhance the catalytic efficiency of GOD. The released 1-MT collaborates with metformin can further enhance immune response to produce apparent cytotoxic T cells. Under laser irradiation, the temperature at the tumor site increases sharply and photo-thermal effect can be generated by the Nb2C and ICG, which can lead to the tumor cell apoptosis, achieving significant photo-thermal therapeutic (PTT) effects. The Nb2C can penetrate into the deep tumor tissue due to its small size. The data revealed that joint use of NMC and NTC can trigger immune response, including the enhancement of CD8+ T cells and CD4+ T cells, the production of INF-γ and TNF-α.

Targeted metabolomics reveals the association between central carbon metabolism and pulmonary nodules.

With the widespread application of low-dose computed tomography (LDCT) technology, pulmonary nodules have aroused more attention. Significant alteration in plasma metabolite levels, mainly amino acid and lipid, have been observed in patients of PNs. However, evidence on the association between central carbon metabolism and PNs are largely unknown. The aim of this study was to investigate the underlying association of PNs and plasma central carbon metabolites. We measured the levels of 16 plasma central carbon metabolites in 1954 participants who gained LDCT screening in MALSC cohort. The inverse probability weighting (IPW) technique was used to control for bias due to self-selection for LDCT in the assessed high-risk population. The least absolute shrinkage and selection operator (LASSO) penalized regression was used to deal with the problem of multicollinearity among metabolites and the combined association of central carbon metabolites with PNs was estimated by using quantile g-computation (QgC) models. A quartile increase in 3-hydroxybutyric acid, gluconic acid, succinic acid and hippuric acid was positively associated with the PNs risk, whereas a quartile increase in 2-oxadipic acid and fumaric acid was negatively associated with the risk of PNs in multiple-metabolite models. A positive but insignificant joint associations of the mixture of 16 metabolites with PNs was observed by using QgC models analyses. Further studies are warranted to clarify the association between circulating metabolites and PNs and the biological mechanisms.

Revealing the phosphate-solubilizing characteristics and mechanisms of the plant growth-promoting bacterium Agrobacterium deltaense C1.

This study explores the phosphate (Pi)-solubilizing characteristics and mechanisms of a novel phosphate-solubilizing bacterium, Agrobacterium deltaense C1 (C1 hereafter). The growth-promoting effects of C1 were investigated by gnotobiotic experiments, and the Pi-solubilizing mechanism was revealed by extracellular metabolomics, liquid chromatography analysis, and reverse transcription quantitative polymerase chain reaction. Results showed that C1 significantly increased Arabidopsis biomass and total phosphorus (P) content under P deficiency. Under Ca3(PO4)2 condition, the presence of C1 resulted in a significant and negative correlation between available P content and medium pH changes, implying that Pi dissolution occurs through acid release. Metabolomics revealed C1's ability to release 99 organic acids, with gluconic acid (GA), citric acid, and α-ketoglutaric acid contributing 64.86%, 9.58%, and 0.94%, respectively, to Pi solubilization. These acids were significantly induced by P deficiency. Moreover, C1's Pi solubilization may remain significant even in the presence of available P, as evidenced by substantial pH reduction and high gcd gene expression. Additionally, C1 produced over 10 plant growth-promoting substances. C1 dissolves Pi primarily by releasing GA, which enhances plant growth under P deficiency. Notably, its Pi solubilization effect is not significantly limited by available Pi.

Rapid Synthesis of Trimetallic Nanozyme for Sustainable Cascaded Catalytic Therapy via Tumor Microenvironment Remodulation.

Tumor microenvironment (TME)-responsive nanozyme-catalyzed cancer therapy shows great potential due to its specificity and efficiency. However, breaking the self-adaption of tumors and improving the sustainable remodeling TME ability remains a major challenge for developing novel nanozymes. Here, a rapid method is developed first to synthesize unprecedented trimetalic nanozyme (AuMnCu, AMC) with a targeting peptide (AMCc), which exhibits excellent peroxidase-like, catalase-like, and glucose oxidase-like activities. The released Cu and Mn ions in TME consume endogenous H2 O2 and produce O2 , while theAMCccatalyzes glucose oxidation reaction to generate H2 O2 and gluconic acid, which achieves the starvation therapy by depleting the energy and enhances the chemodynamic therapy effect by lowering the pH of the TME and producing extra H2 O2 . Meanwhile, the reactive oxygen species damage is amplified, as AMCc can constantly oxidize intracellular reductive glutathione through the cyclic valence alternation of Cu and Mn ions, and the generated Cu+ elevate the production of ·OH from H2 O2 . Further studies depict that the well-designed AMCc exhibits the excellent photothermal performance and achieves TME-responsive sustainable starvation/photothermal-enhanced chemodynamic synergistic effects in vitro and in vivo. Overall, a promising approach is demonstrated here to design "all-in-one" nanozyme for theranostics by remodeling the TME.

Synthesis and application of a new antibacterial surfactant from apricot kernel oil

Food emulsifier are mostly prepared from a lipophilic lipid tail with a hydrophilic sugar head. In this study, the lipophilic tail was obtained from apricot kernels, which are food waste, and the hydrophilic head was gluconic acid instead of sugar, in order to draw attention to the non-cyclic poly hydroxyl compounds. Thus, oleic acid of apricot kernel was used as the lipophilic moiety of the prepared surfactant. So, apricot kernel was grinned and dried, oil was extracted using soxhlet apparatus, Physical and chemical parameters and fatty acids composition of the extracted oil had been determined. The extracted oil was then hydrolyzed into glycerol and a mixture of free fatty acids. The fatty acids mixture was separated. Then, oleic acid was extracted individually in pure form using supercritical CO2 extractor, it was then confirmed according to its melting point, Gas chromatography–mass spectrometry (GC–MS) after esterification, elemental analysis, Proton nuclear magnetic resonance (H1NMR), and mass spectrometry (MS) to detect the corresponding molecular ion peak. The pure individual oleic acid was converted to hydroxy stearic acid, which was then converted to an amphiphilic compound (surfactant) via esterification reaction with the hydrophilic gluconic acid, and afforded a new surfactant known as 2,3,4,5-tetrahydroxy-6-((9-((-2,3,4,5,6-pentahydroxyhexanoyl) oxy)octadecanoyl) oxy)hexanoic acid or stearyl gluconate for simplification. The structures elucidation of all synthesized compound was established according to elemental analysis and spectral data (Fourier transform infrared IR, 1H NMR, 13C NMR and MS). Moreover, the prepared compound was tasted for its antibacterial activity, and showed good activities against some types of bacteria. The surface-active properties, foamability, foaming stability and emulsion stability of stearyl gluconate were studied and compared with the properties of the well-known surfactant sucrose stearate, and it was clear that, the activity of stearyl gluconate as a surfactant was higher than that of sucrose stearate. Moreover, establishment of safety of this compound was performed using albino rats by acute oral toxicity and kidney and liver functions of these mice. On the other hand, the prepared surfactant was used in the production of low fat—free cholesterol mayonnaise as egg replacer. Texture properties and the sensory evaluation of the prepared mayonnaise showed that the properties were improved by using the new prepared surfactant. Thus, the prepared gluconyl stearate can be used as a safe food additive.

Techno-economic Analysis and Life Cycle Assessment of Gluconic Acid and Xylonic Acid Production from Waste Materials

Techno-economic Analysis and Life Cycle Assessment of Gluconic Acid and Xylonic Acid Production from Waste Materials

High-performance thin-layer chromatography‒multi-stage mass spectrometry methods for analyses of bee pollen botanically originating from sweet chestnut (Castanea sativa Mill.)

High-performance thin-layer chromatographic (HPTLC) silica gel and amino plates in combination with developing solvents containing formic and acetic acid were examined for HPTLC‒multi-stage mass spectrometry (MSn) analyses of chestnut bee pollen samples from Slovenia and Türkiye. Ethyl acetate‒formic acid‒acetic acid‒water (10:1.1:1.1:2.6, V/V) and ethyl acetate‒dichloromethane‒formic acid‒acetic acid (10:2.5:1:1.1, V/V) were used for development of silica gel and amino plates, respectively. Twofold pre-development was required for the developed HPTLC‒MSn methods. The first pre-development was performed with methanol‒formic acid (10:3, V/V) for silica gel plates and methanol‒formic acid (10:5, V/V) for amino plates. The second pre-development with methanol was equal for both types of the plates. Using the developed HPTLC‒MSn methods, five phenylamides (spermidines), six isorhamnetin glycosides and gluconic acid were identified in both chestnut bee pollen samples. Glycosylated phenolic acid (caffeic acid-hexoside) was detected only in the Turkish bee pollen sample. To the best of our knowledge, this is the first report on isorhamnetin-(hexosyl)hexoside, isorhamnetin-acetylhexoside, isorhamnetin-(pentosyl-deoxyhexosyl)hexoside and caffeic acid-hexoside in chestnut bee pollen. This is also the first report on isorhamnetin-(pentosyl-deoxyhexosyl)hexoside and caffeic acid-hexoside in any bee products.

Enhancement of the phenolic compounds and antioxidant activities of Kombucha prepared using specific bacterial and yeast

The symbiotic culture of bacteria and yeast (SCOBY) encompasses a diverse array of microorganisms that play a pivotal role in the biochemical transformations during Kombucha fermentation. This study aims to investigate how various combinations of acetic acid bacteria (AAB) and specific yeast strains influence SCOBY formation and the biochemical characteristics of Kombucha. Thirteen combinations of AAB and yeasts formed SCOBY. The pH of Kombucha decreased to 2.31, and titratable acidity content increased to 20.76 g/L. Acetic and gluconic acid contents of Kombucha were 1.96 g/L and 6.9 g/L, respectively. The total phenolic and flavonoid contents increased by 3.53- and 5.2 fold, whereas the condensed tannin content decreased by 31.3 fold. Chlorogenic, p-coumaric, and ferulic acids were newly detected. Catechin, epicatechin, caffeine, caffeic acid, gallic acid, and rutin contents in Kombucha were increased. The antioxidant activity of Kombucha was enhanced up to 2.88 fold. The use of AAB and yeast has potential value in the industrial production of Kombucha.

PH-Sensitive Glucose-Powered Nanomotors for Enhanced Intracellular Drug Delivery and Ferroptosis Efficiency.

We propose a glucose-powered Janus nanomotor where two faces are functionalized with glucose oxidase (GOx) and polydopamine-Fe3+ chelates (PDF), respectively. In the glucose fuel solution, the GOx on the one side of these Janus nanomotors catalytically decomposes glucose fuels into gluconic acid and hydrogen peroxide (H2 O2 ) to drive them at a speed of 2.67 μm/s. The underlying propulsion mechanism is the glucose-based self-diffusiophoresis owing to the generated local glucose concentration gradient by the enzymatic reaction. Based on the enhanced diffusion motion, such nanomotors with catalytic activity increase the uptake towards cells and subsequently exhibit excellent capabilities for Fe3+ ions delivery and H2 O2 generation for enhancing ferroptosis efficiency for inducing cancer cell death. In particular, the Fe3+ ions are released from nanomotors in a slightly acidic environment, and subsequently generate toxic hydroxyl radicals via Fenton reactions, which accumulation reactive oxygen species (ROS) level (~300 %) and further lipid peroxidation (LPO) strengthened ferroptosis therapy for cancer treatment. The as-developed glucose-powered Janus nanomotor with efficient diffusion and Fe ions delivery capabilities show great promise as a potential in biomedical applications.

Chemical composition, antifungal, and anti-virulence action of the stem bark of Hancornia speciosa Gomes (Apocynaceae) against Candida spp.

Ethnopharmacological relevanceHancornia speciosa Gomes is a fruit and medicinal species used for treating infectious diseases of the genitourinary system. However, its mechanism of action against microbes is still not fully understood. Infections in the genitourinary system caused by Candida spp. are associated with its fungal resistance and pathogenicity. New plant-derived compounds are an alternative to fight these Candida infections. Aim of the studyThe objective of this study was to evaluate the anti-Candida effects of extracts of the stem bark of H. speciosa. This research investigated the chemical composition of sulfuric ether (EEHS) and methanolic (MEHS) extracts, their drug-modifying action on fluconazole, and their anti-virulence action on the morphological transition of Candida species. Materials and methodsThe extracts (EEHS and MEHS) of the stem bark of H. speciosa were chemically characterized via qualitative phytochemical screening and by liquid chromatography coupled with mass spectrometry (UPLC-MS-ESI-QTOF). The extracts were evaluated regarding their antifungal effects and fluconazole-modifying activity against Candida albicans, Candida krusei, and Candida tropicalis using the broth microdilution method. Additionally, the study evaluated the inhibition of fungal virulence in Candida species through morphological transition assays. ResultsThe phytochemical screening revealed the presence of anthocyanidins, anthocyanins, aurones, catechins, chalcones, flavones, flavonols, flavanones, leucoanthocyanidins, tannins (condensed and pyrogallic), and xanthones in both extracts of the stem bark of H. speciosa. The UPLC-MS-ESI-QTOF analysis identified the same compounds in both extracts, predominating phenolic compounds. Some compounds were first time recorded in this species: gluconic acid, cinchonain IIb, cinchonain Ib isomer, and lariciresinol hexoside isomers. Most of the intrinsic antifungal activity was observed for the MEHS against C. krusei (IC50: 58.41 μg/mL). At subinhibitory concentrations (MC/8), the EEHS enhanced the action of fluconazole against all Candida strains. The MEHS exhibited greater efficacy than fluconazole inhibiting C. krusei growth. The EEHS completely inhibited hyphae appearance and reduced pseudohyphae formation in C. albicans. ConclusionThe stem bark of H. speciosa is a rich source of bioactive compounds, especially phenolic. Phenolic compounds can have important roles in fighting infectious diseases of the genitourinary system, such as candidiasis. The extracts of H. speciosa improved the action of the drug fluconazole against Candida species, inhibited hyphae appearance, and reduced pseudohyphae formation. The results of this study can support the development of new therapeutics against resistant strains of Candida.

A novel cascade catalytic electrochemical biosensor based on bifunctional Mn3O4@AuNPs with self-supplied O2 property and glucose oxidase-like activity for ultrasensitive detection of microRNA

Herein, a bifunctional nanomaterial Mn3O4@AuNPs with self-supplied oxygen (O2) property and glucose oxidase-like activity was exploited to construct a novel cascade catalytic electrochemical biosensor for ultrasensitive detection of microRNA-499 (miRNA-499). Impressively, compared with the traditional AuNPs nanozyme with single glucose oxidase-like activity, the Mn3O4@AuNPs could not only act as a glucose oxidative mimetic enzyme to catalyze the oxidation of glucose to gluconic acid and the reduction of dissolved O2 to low concentration of hydrogen peroxide (H2O2) to obtain a electrochemical signal in the presence of hemin/G-quadruplex DNAzyme with peroxidase-like activity, but also electrocatalyze water splitting to obtain abundant dissolved O2 to further assist in the production of high concentration of H2O2 for a significantly improved electrochemical response. Meanwhile, with the aid of the target-induced dual Mg2+-assisted DNAzyme cleavage recycling amplification for the increasement of target miRNA-499 conversion efficiency, the proposed electrochemical biosensor achieved the ultrasensitive detection of miRNA-499 with a detection limit as low as 6.2 aM. As a result, this strategy might provide a potential method to upgrade the catalytic efficiency of mimic enzyme cascade reaction with eventual applications in bioanalysis and disease diagnosis.

Characterization of glucose Oxidase from Penicillium chrysogenum MDC 8358: Prospects for application in food industry

Backgrounds: Food enzymes play a crucial role in enhancing specific food attributes, such as improving texture, eliminating toxins and allergens, producing carbohydrates, and enhancing flavor and appearance characteristics. Glucose oxidase (GOX) catalyzes the oxidation of glucose to produce gluconic acid and hydrogen peroxide, making it applicable in various practical scenarios. This enzyme could be utilized to eliminate glucose, thereby facilitating the creation of functional food suitable for individuals with diabetes and glucose intolerance.Our main goal was to characterize GOX from a Penicillium chrysogenum strain isolated from Armenian ecosystems.Methods:GOX of P. chrysogenum MDC 8358 was obtained by surface fermentation using glucose as a carbon source. The enzyme was purified 230-fold to homogeneity using a three-step purification scheme consisting of ion exchange, adsorption, and gel filtration chromatography. Results:The specific activity of the purified enzyme reached 271.2 U/mg. GOX from P. chrysogenum MDC 8358 has shown to be dimeric with a molecular weight of 135.5 kDa, consisting of two equal subunits with a molecular weight of 70 kDa. Isoelectric focusing has revealed a pH of 4.6. The enzyme has displayed a temperature optimum of 40 °C, and a pH optimum of 6.8, being more thermostable at acidic pH. Characterized GOX was highly specific for β-D-glucose and has shown only minor activities to mannose, xylose, and galactose. Keywords:Penicillium chrysogenum MDC 8358, surface fermentation, glucose oxidase, purification, characterization, functional food preservation

Osmium‐Doped WO2.72 as a Promising Electrocatalyst for Hydrogen Evolution Linking to Glucose Oxidation

Herein, the organic matter is reported to reduce the overpotential of oxygen evolution reaction (OER) for water splitting. Herein, osmium (Os) is doped into WO2.72 to form Os–WO2.72 as an electrocatalyst, which is applied into water splitting to produce hydrogen and assist promote glucose oxidization reaction (GOR). The OER overpotential of 0.05 Os–WO2.72 is only 248 mV at 10 mA cm−2 in 1 m KOH, which is much superior to commercial RuO2. Additionally, the 0.05 Os–WO2.72 has ultralow GOR overpotential of 158 mV at 10 mA cm−2 and 365 mV at 100 mA cm−2 in 1 m KOH with 0.1 m glucose, and the cell voltage is 1.37 V at 10 mA cm−2, the values are much lower than its electrocatalytic behaviors in 1 m KOH. The anode produces gluconic acid, which is an important industrial intermediate during hydrogen production at the cathode.

Whole-Genome Analysis of Novacetimonas cocois and the Effects of Carbon Sources on Synthesis of Bacterial Cellulose

Novacetimonas cocois WE7 (formally named Komagataeibacter cocois WE7) is a strain isolated from contaminated coconut milk, capable of producing bacterial cellulose (BC). We sequenced its genome to investigate why WE7 cannot synthesize BC from glucose efficiently. It contains about 3.5 Mb and six plasmid DNAs. N. cocois WE7 contains two bcs operons (bacterial cellulose operon, bcs I and bcs II); the absence of bcs III operons may lead to reduced BC production. From genome predictions, glucose, sucrose, fructose, maltose, and glycerol can be utilized to generate BC, with WE7 unable to metabolize carbohydrate carbon sources through the Embden–Meyerhof–Parnas (EMP) pathway, but rather through the Hexose Monophosphate Pathway (HMP) and tricarboxylic acid (TCA) pathways. It has a complete gluconic acid production pathway, suggesting that BC yield might be very low when glucose, maltose, and trehalose are used as carbon sources. This study represents the first genome analysis of N. cocois. This information is crucial for understanding BC production and regulation mechanisms in N. cocois and lays a foundation for constructing engineered strains tailored for diverse BC application purposes.

A multivalent polyphenol–metal-nanoplatform for cascade amplified chemo-chemodynamic therapy

Chemodynamic therapy (CDT), as an emerging therapeutic strategy, kills cancer cells by converting intracellular hydrogen peroxide (H2O2) into cytotoxic oxidizing hydroxyl radicals (⋅OH). However, the therapeutic efficiency of CDT is compromised due to the insufficient endogenous H2O2 and metal catalysts in tumor cells. The use of multivalent polyphenols with multiple hydroxyl functions provides a facile yet robust means for efficient CDT augmentation. For this purpose, we reported herein the construction of polyphenol–metal nanoparticles (NPs) via a phenol–metal coordination strategy. The uniqueness of this study is the preparation of only one polymer construct with multivalency that can afford various supramolecular interactions for simultaneous “one-pot” loading of different therapeutic species, i.e., doxorubicin (DOX), glucose oxidases (GOD), and Fe3+ and further co-self-assembly into a stabilized nanomedicine for cascade amplified chemo-chemodynamic therapy. Specifically, the tumor intracellular acidic pH-triggered DOX release could serve for chemotherapy as well as enhance the intracellular H2O2 level. Together with the extra H2O2 and gluconic acid produced by the GOD-triggered glucose consumption, DOX@POAD-Fe@GOD NPs promoted Fe3+participation in the Fe-mediated Fenton reaction for cascade amplified chemo-chemodynamic therapy. Notably, this formulation displayed a greater anti-tumor effect with a tumor inhibition ratio 1.6-fold higher than that of free DOX in a BALB/c mice model bearing 4T1 tumors. Overall, the multivalent polyphenol–metal nanoplatform developed herein integrates chemotherapy, starvation therapy, and CDT for synergistic enhanced anticancer efficiency, which shows great potential for clinical translations. Statement of significanceChemodynamic therapy (CDT) generally suffers from compromised therapeutic efficiency due to insufficient endogenous H2O2 and metal catalysts in tumor cells. To develop a facile yet robust strategy for efficient CDT augmentation, we reported herein construction of a multivalent polyphenol–metal nanoplatform, DOX@POAD-Fe@GOD nanoparticles (NPs) via a phenol–metal coordination strategy. This nanoplatform integrates multiple supramolecular dynamic interactions not only for simultaneously safe encapsulation of doxorubicin (DOX), Fe3+, and glucose oxidases (GOD), but also for cascade amplified chemo-chemodynamic therapy. Specifically, the intracellular acidic pH-triggered dissociation of DOX@POAD-Fe@GOD NPs promoted the release of Fe3+, DOX, and GOD for significantly increased ROS levels that can accelerate Fenton reactions for cascaded chemotherapy, starvation therapy, and CDT with amplified antitumor efficiency in vivo.

Gold mineralized “hybrid nanozyme bomb” for NIR-II triggered tumor effective permeation and cocktail therapy

Lung cancer is one of the most common malignant tumors with the fastest increase in the incidence rate and mortality. Even after maximum tumor resection assistance with a radiotherapy and chemotherapy combination, the recurrence of non-small cell lung cancer is still inevitable. In addition, low targeting efficiency and poor permeability of drug delivery systems strongly affect the therapeutic efficiency of anti-cancer drugs on non-small cell lung cancer. Here we designed a gemcitabine (GEM) loaded arginine-glycine-aspartic acid-cysteine (RGDc)-modified gold mineralization “hybrid nanozyme bomb” (RGTG) to overcome those obstacles. RGDc modification improved the active targeting of liposomes to the tumor tissues with the second near-infrared (NIR-II)-triggered gold-shell disruption and GEM release. The collapsed gold-shell particles with a smaller size could penetrate the tumor solid barrier and act as photothermal therapy (PTT) agents to improve PTT therapy and starvation therapy via generating gluconic acid and reactive oxygen species (ROS). Moreover, the resting reversal effect of gold particles on tumor fibroblasts can achieve accelerating tumor penetration of gold particles and GEM. Compared to monotherapy, RGTG showed significant improvement in tumor inhibition, with a tumor volume reduction of 83% compared to the control group, which provides a promising tumor treatment platform for non-small cell lung cancer (NSCLC).

The influence of Acetobacter pomorum bacteria on the developmental progression of Drosophila suzukii via gluconic acid secretion.

Insects are rich in various microorganisms, which play diverse roles in affecting host biology. Although most Drosophila species prefer rotten fruits, the agricultural pest Drosophila suzukii attacks ripening fruits before they are harvested. We have reported that the microbiota has positive and negative impacts on the agricultural pest D. suzukii on nutrient-poor and -rich diets, respectively. On nutrient-poor diets, microbes provide protein to facilitate larval development. But how they impede D. suzukii development on nutrient-rich diets is unknown. Here we report that Acetobacter pomorum (Apo), a commensal bacterium in many Drosophila species and rotting fruit, has several detrimental effects in D. suzukii. Feeding D. suzukii larvae nutrient-rich diets containing live Apo significantly delayed larval development and reduced the body weight of emerged adults. Apo induced larval immune responses and downregulated genes of digestion and juvenile hormone metabolism. Knockdown of these genes in germ-free larvae reproduced Apo-like weakened phenotypes. Apo was confirmed to secrete substantial amounts of gluconic acid. Adding gluconic acid to the D. suzukii larval diet hindered larval growth and decreased adult body weight. Moreover, the dose of gluconic acid that adversely affected D. suzukii did not negatively affect Drosophila melanogaster, suggesting that D. suzukii is less tolerant to acid than D. melanogaster. Taken together, these findings indicate that D. suzukii is negatively affected by gluconic acid, which may explain why it prefers ripening fruit over Apo-rich rotting fruit. These results show an insect's tolerance to microbes can influence its ecological niche.