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The microbial potential of Penicilliumhas received critical attention. The present research aimed to elucidate the efficacy of crude enzyme secreted from Penicillium oxalicumWX-209 in degrading citrus segments and evaluate the safety of the process. Results showed that citrus segment membranes gradually dissolved after treatment with the crude enzyme solution, indicating good degradation capability. No significant differences in body weight, food ingestion rate, hematology, blood biochemistry, and weight changes of different organs were found between the enzyme intake and control groups. Serial experiments showed that the crude enzyme had high biological safety. Moreover, the whole genome of P. oxalicumWX-209 was sequenced by PacBio and Illumina platforms. Twenty-five scaffolds were assembled to generate 36 Mbp size of genome sequence comprising 11 369 predicted genes modeled with a GC content of 48.33 %. A total of 592 genes were annotated to encode enzymes related to carbohydrates, and some degradation enzyme genes were identified in strain P. oxalicumWX-209.

Enzyme promiscuity is evolutionarily advantageous to plants for gaining new enzyme functions when adapting to environmental challenges. However, this promiscuity can negatively affect the expression of genes encoding for plant enzymes in microorganisms. Here, we show that refining the promiscuity of flavonoid 3′-hydroxylase (F3′H) and 4′-O-methyltransferase (F4′OMT) improves (2S)-hesperetin production in Escherichia coli. First, we employed inverse molecular docking to screen a highly substrate-specific ThF3′H from Tricyrtis hirta, which could selectively convert 100 mg L–1(2S)-naringenin to (2S)-eriodictyol but not (2S)-isosakuranetin, with a cytochrome P450 reductase from Arabidopsis thaliana. Second, we employed a directed evolution approach to restrict the promiscuity of MpOMT from Mentha × piperita. The strain harboring the MpOMTS142Vmutant presented a remarkably increased preference for (2S)-eriodictyol. Finally, 27.5 mg L–1(2S)-hesperetin was produced, while only minor amounts of (2S)-eriodictyol and (2S)-isosakuranetin accumulated as byproducts. This value represents a 14-fold increase in (2S)-hesperetin compared to the parental strain, along with a dramatic reduction in side products. Our work highlights the benefit of alleviating the promiscuity of plant enzymes when engineering production of natural products by microbial cell factories.

High-fat diet (HFD) is closely related to the formation of metabolic diseases. Studies have confirmed that neohesperidin dihydrochalcone (NHDC) possesses the biological activity of preventing glycolipid metabolism disorder. To explore the mechanism of its preventive activity against glucolipid metabolism disorder, HFD-treated rats were orally administered with NHDC for 12 weeks continuously. The results showed that, compared with the HFD group, the intervention of 40–80 mg/kg body weight of NHDC effectively downregulated the level of fasting blood glucose. Western blot analysis revealed that the treatment of NHDC alleviated the inhibitory effect of HFD on the expression of hepatic GLUT-4 and IRS-1. Further studies confirmed that NHDC reduced the degree of HFD-stimulated inflammation of ileum through the TLR4/MyD88/NF-κB signaling pathway. Moreover, ileum intestinal flora analysis showed that intragastric administration of NHDC reversed the change of Proteobacteria abundance and the Firmicutes/Bacteroidetes (F/B) ratio caused by HFD. At the generic level, NHDC promoted the relative abundance of Coprococcus, Bifidobacterium, Clostridium, Oscillospira, and [Eubacterium], while reducing the relative abundance of Defluviitaleaand Prevotella. Taken together, these findings suggest that NHDC possesses the biological activity of improving HFD-induced glycolipid metabolism disorder.

Prussian blue (PB) and its analogues (PBAs) are promising coordination polymers (CPs) with an adjustable composition and open framework. Nonetheless, their intrinsic electrochemical activity and electrical conductivity are poor, which hinder their applications in energy conversion and storage. In catalytic applications, metal compounds derived from PB/PBAs have a lot of advantages, such as outstanding stability, selectivity, and electrical conductivity. Furthermore, they can be used as electrode materials for electrochemical energy storage and conversion, while having preferable electronic conductivity, sufficient catalytic active sites, as well as a larger specific surface area and tunable size to achieve an optimized performance. This review summarizes the current achievements of PB/PBA-derived metallic nanomaterials, as well as the existing limitations, urgent challenges and future development.The electrochemical applications of Prussian blue/Prussian blue analogues-derived non-oxidized metallic materials are overviewed. Based on a variety of structures, various materials, including sulfides, phosphates, selenides, etc., are reviewed, and optimization strategies for new energy storage and conversion devices are given. We aim to provide readers with the latest progress on this rapidly developing area.

The controllable synthesis of metal-based nanoclusters for heterogeneous catalytic reactions has received considerable attention. Nevertheless, manufacturing these architectures, while avoiding aggregation and retaining surface activity, remains challenging. Herein, for the first time we designed NiCoFe-Prussian blue analogue (PBA) nanocages as a support for in situ dispersion and anchoring of polymetallic phosphide nanoparticles (pMP-NPs). Benefiting from the porous surfaces and the synergistic effects between pMP-NPs and the cyano groups in PBA, the NiCoFe-P-NP@NiCoFe-PBA nanocages exhibit a significantly enhanced catalytic activity for oxygen evolution reaction (OER) with an overpotential of 223 mV at 10 mA cm–2and a Tafel slope of 78 mV dec–1, outperforming the NiCoFe-PBA nanocubes, NiCoFe-P nanocages, NiFe-P-NP@NiFe-PBA nanocubes, and CoFe-P-NP@CoFe-PBA nanoboxes. This work not only offers the synthesis strategy of in situ anchoring pMP-NPs on PBA nanocages but also provides a new insight into optimized Gibbs free energy of OER by regulating electron transfer from metallic phosphides to PBA substrate.

Obesity is a global pandemic and public health crisis over decades. Except for physical activity, dietary adjustments, pharmacotherapy and surgical interventions, prebiotics, which are believed to relieve obesity by modulating the host gut microbiota, have been a hot research area in recent years. Thus, in this study, our objective was to investigate the effects of Citrus aurantiumL. 'Daidai' physiological premature fruit drop (DDPD) on obesity, and further explore whether the anti-obesity effects of DDPD relies on alterations in gut microbiota. Our findings revealed that supplementation with DDPD effectively alleviated HFD-induced obesity in mice, concomitantly reducing inflammation and oxidative stress. Moreover, DDPD reversed the imbalance of gut microbiota induced by HFD, enhancing beneficial bacteria associated with improved obesity, such as Bifidobacterium, Lachnospiraceae_NK4A136_group, Ruminococcus, and Muribaculaceae. Fecal microbiota transplantation experiments demonstrated that DDPD-induced alterations in microbiota effectively mitigated weight gain and lipid abnormalities induced by HFD, while reshaping the microbiota composition of recipient mice to resemble that of donor mice. Notably, beneficial lipid metabolism bacterium Lachnospiraceae_NK4A136_groupidentified in donor mice successfully colonized in recipient mice. Additionally, transcriptomic analysis indicated that DDPD modulated lipid metabolism through regulating the expression of genes linked to Cpt1a, Agpat1, and Pnpla3. In conclusion, DDPD demonstrated promising anti-obesity properties, offering potential solutions to the global obesity epidemic.

Temperature is the most important factor that affects the metabolism of harvested plants. The aim of this study was to investigate the influence and mechanisms of temperature on the antioxidant system in fresh-cut daylily flowers (Hemerocallis lilioasphodelusL.; used for food consumption) during storage. Daylily flowers were harvested and immediately treated by either chilling at 5 °C for 5 days, or by heating with 50 °C hot air for 5 min, then stored at 20 °C for 5 days. The chilling and heating treatments maintained the organoleptic quality and enhanced the antioxidant system of cut daylily flowers. However, different reactions of the antioxidant system were observed under the different temperature treatments. The chilling treatment dramatically enhanced the activities of superoxide dismutase, ascorbate peroxidase, peroxidase, and phenylalanine ammonia lyase, while it decreased the activity of lipoxygenase. Meanwhile, the heating treatment enhanced catalase activity and decreased polyphenol oxidase activity. In addition, the heating treatment reduced the O2−production rate and H2O2content compared to the control. Changes in membrane permeability, total phenolic content, total flavonoid content, and diphenyl-1-picrylhydrazyl clearance activity showed no significant difference between the chilling and heating treatments, owning to the steady content of phenolic and flavonoid compounds and the delay in the generation of quinones. Thus, our results indicate that cold and heat treatments can impact the preservation of harvested daylilies used for food consumption.

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Diabetes elevates matrix metalloproteinase-9 (MMP-9) in the retina and its capillary cells, and activated MMP-9 damages mitochondria, accelerating retinal capillary cell apoptosis, a phenomenon which precedes the development of retinopathy. Diabetes also favors epigenetic modifications regulating the expression of many genes. DNA methylation is maintained by methylating–hydroxymethylating enzymes, and retinal DNA methyltransferase (Dnmt) is activated in diabetes. Our aim is to investigate the role of DNA methylation in MMP-9 regulation. The effect of high glucose on 5-methylcytosine (5mC) and 5-hydroxymethyl cytosine (5hmC), and binding of Dnmt1 and hydroxymethylating enzyme (Tet2) on MMP-9 promoter were quantified in retinal endothelial cells. Specific role of Tet2 in MMP-9 activation was validated using Tet2-siRNA. The results were confirmed in the retina from streptozotocin-induced diabetic mouse. Although glucose increased Dnmt1 binding at MMP-9 promoter, it decreased 5mC levels. At the same promoter site, Tet2 binding and 5hmC levels were elevated. Tet2-siRNA ameliorated increase in 5hmC and MMP-9 transcription, and protected mitochondrial damage. Diabetic mice also presented similar dynamic DNA methylation changes in the retinal MMP-9 promoter. Thus, in diabetes transcription of retinal MMP-9 is maintained, in part, by an active DNA methylation–hydroxymethylation process, and regulation of this machinery should help maintain mitochondrial homeostasis and inhibit the development/progression of diabetic retinopathy.

Diabetes elevates matrix metalloproteinase-9 (MMP-9) in the retina and its capillary cells, and activated MMP-9 damages mitochondria, accelerating retinal capillary cell apoptosis, a phenomenon which precedes the development of retinopathy. Diabetes also favors epigenetic modifications regulating the expression of many genes. DNA methylation is maintained by methylating–hydroxymethylating enzymes, and retinal DNA methyltransferase (Dnmt) is activated in diabetes. Our aim is to investigate the role of DNA methylation in MMP-9regulation. The effect of high glucose on 5-methylcytosine (5mC) and 5-hydroxymethyl cytosine (5hmC), and binding of Dnmt1 and hydroxymethylating enzyme (Tet2) on MMP-9promoter were quantified in retinal endothelial cells. Specific role of Tet2 in MMP-9activation was validated using Tet2-siRNA. The results were confirmed in the retina from streptozotocin-induced diabetic mouse. Although glucose increased Dnmt1 binding at MMP-9promoter, it decreased 5mC levels. At the same promoter site, Tet2 binding and 5hmC levels were elevated. Tet2-siRNA ameliorated increase in 5hmC and MMP-9transcription, and protected mitochondrial damage. Diabetic mice also presented similar dynamic DNA methylation changes in the retinal MMP-9promoter. Thus, in diabetes transcription of retinal MMP-9is maintained, in part, by an active DNA methylation–hydroxymethylation process, and regulation of this machinery should help maintain mitochondrial homeostasis and inhibit the development/progression of diabetic retinopathy.

Solid-state mechanochemical grinding is important for promoting cocrystal formation, particularly in the design of new solids in the pharmaceutical industry. Pharmaceutical cocrystals are defined as crystalline materials comprising an active pharmaceutical ingredient (API) and one or more appropriate coformers in a definite stoichiometric ratio, formed via non-covalent interactions. Recently, both the US FDA (2013) and the EU EMA (2015) provided a Guidance for Industry and a Reflection Paper, respectively, emphasizing that cocrystals are a new type of substance with potential applications in the pharmaceutical industry. This paper contains a brief and systematic overview of pharmaceutical cocrystals prepared by four grinding processes: neat grinding, solvent-assisted grinding, thermal stress after neat grinding, and polymer-assisted grinding. The paper also highlights some examples of pharmaceutical cocrystals prepared by the above grinding approaches, and discusses the stability of cocrystals prepared by mechanical grinding. Also, an overview of cocrystals that are commercially available or undergoing clinical trials is given. A novel methodology for real-time and in situ monitoring of mechanochemical grinding reactions using various analytical techniques is addressed and can be expected to be applied in the near future.

Ganoderma lucidum(G. lucidum) is one of the well-known mushrooms in China, which has G. lucidum polysaccharides (GLP) that have been widely studied for various biological activities, such as antioxidant, antitumor, antiinflammatory, antiviral, antidiabetes, and immunomodulatory activities. A signal transducer and activator of transcription (STAT) signaling pathway is related to cell proliferation and apoptosis. The relationship between STAT and intestinal protection of GLP is still unknown. We studied the inhibitors AG490 in the STAT pathway and its downstream molecules to analyze the unique effects in the protection of GLP against palmitic acid (PA)-induced porcine intestinal epithelial cells (IPEC-J2) injury. Compared to PA treatment, GLP?+?PA obviously decreased Ca2+concentration, H2O2production, NF-E2-related factor 2 (Nrf2) nuclear translocation, STAT1 and STAT2 protein levels, and increased nuclear factor kappa-B (NF-?B) nuclear translocation and p-STAT3/STAT3 ratio in IPEC-J2 cells. After inhibition of STAT3 signaling, p-STAT3/STAT3 ratio, NF-?B nuclear translocation obviously decreased and Nrf2 nuclear translocation significantly increased in the GLP?+?PA group. The protection of GLP on proliferation and apoptosis of PA-induced IPEC-J2 cells was suppressed by inhibiting STAT3. The STAT3 pathway regulated the enterocyte-protective effects of GLP by modulating the nuclear translocation of Nrf2 and NF-?B. We provide new insights into the mechanism of STAT signaling for the protection of GLP on PA-induced intestinal epithelial cell injury.

The effect of Povacoat on the solid state characteristics and polymorphic transformation of γ-form of indomethacin (γ-IMC) after solvent co-evaporation via two drying methods was investigated by thermoanalytical and FTIR spectroscopic studies. The types of solvents (water, ethanol, and water:ethanol (1:9 ~ 2:8, v/v)), weight ratios of Povacoat:IMC (4:1 ~ 4:10, w/w), and drying methods (air-drying and microwave-drying) were selected as variables in this study. A physical mixture of Povacoat and γ-IMC was also carried out by neat grinding process. The results indicate that there was no interaction between Povacoat and γ-IMC or no polymorphic change of γ-IMC after the neat co-grinding process. Since Povacoat was only soluble in water or <30% ethanol aqueous solution but γ-IMC was only soluble in organic solvents, different solvents and drying methods might significantly influence the solid-state characteristics of IMC formed in the presence of Povacoat. It was found that the amorphous IMC was formed in the Povacoat/IMC evaporates after dissolving both Povacoat and γ-IMC in water:ethanol (mixed ratio=1:9 and 2:8, v/v) and co-evaporation via microwave-drying, whereas the α-IMC was formed in the Povacoat/IMC evaporates via the air-drying method. In addition, the predominate α-IMC formation was only found in all the Povacoat/IMC evaporates with different weight ratios prepared by previously dissolving in water:ethanol (1:9, v/v) and co-evaporation via air-drying, but the amorphous IMC formation after co-evaporation via microwave-drying was obtained except the 4:10 (w/w) weight ratio. The thermal effect of microwave irradiation and the presence of Povacoat might be responsible for the amorphous IMC formation in the Povacoat/IMC evaporates.

An acute sludge was unexpectedly produced in the gallbladder of a woman with acute myocarditis, liver dysfunction and acute cholecystitis. This study aimed to determine whether the morphological features and chemical composition of this acute gallbladder sludge were different from common chronic gallstones. This acute gallbladder sludge and 12 patients' chronic gallstones were analyzed using histopathological examination, SEM, FTIR spectroscopy and X-ray fluorescence analysis. The chronic gallstones from the 12 patients were classified into calcium bilirubinate (CaBR), cholesterol (Chol) and CaBR–Chol mixed stones. The acute gallbladder sludge was not consistent with chronic gallstones but had developed within the prior 3 months of medical care, which only comprised CaBR and protein/biomaterials. Moreover, none of the long-term transition elements including Pb, Hg, Au, Sn, Sr, Rb, Br, Se and Cr had accumulated in the acute gallbladder sludge but they had found in chronic CaBR gallstone, however, the elements Hf, Co and Ti were present in the acute gallbladder sludge. The levels of Zn, Cu, Mn and Ca were lower in acute gallbladder sludge than in chronic gallstones. Our results indicate that this acute gallbladder sludge comprised large amounts of protein/biomaterials with fewer CaBR aggregates and had different element contents as compared with common chronic gallstones.

We report a potential application of a portable fiber-optic Raman spectroscopy for fast prostatic calculi diagnosis. A portable Raman analyzer with a fiber-optic probe was first used to identify and differentiate the mineral components of prostate stones. The study indicates that three types of stones, hydroxyapatite (HA) stone, calcium oxalate dehydrate (COD) stone and mixed stone including HA, calcium oxalate monohydrate (COM) and COD, were directly detected from 15 patients with prostatic calculi in a short time. The present study reveals that this portable fiber-optic Raman spectroscopic technique was an easy and fast “real-time” tool to differentiate the mineral components in prostatic calculi.