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1.
Biosens Bioelectron ; 264: 116642, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39126905

RESUMO

Real-time, high-frequency measurements of pharmaceuticals, metabolites, exogenous antigens, and other biomolecules in biological samples can provide critical information for health management and clinical diagnosis. Electrochemical aptamer-based (EAB) sensor is a promising analytical technique capable of achieving these goals. However, the issues of insufficient sensitivity, frequent calibration and lack of adapted portable electrochemical device limit its practical application in immediate detection. In response we have fabricated an on-chip-integrated, cold-hot Janus EAB (J-EAB) sensor based on the thermoelectric coolers (TECs). Attributed to the Peltier effect, the enhanced/suppressed current response can be generated simultaneously on cold/hot sides of the J-EAB sensor. The ratio of the current responses on the cold and hot sides was used as the detection signal, enabling rapid on-site, calibration-free determination of small molecules (procaine) as well as macromolecules (SARS-CoV-2 spike protein) in single step, with detection limits of 1 µM and 10 nM, respectively. We have further demonstrated that the J-EAB sensor is effective in improving the ease and usability of the actual detection process, and is expected to provide a universal, low-cost, fast and easy potential analytical tool for other clinically important biomarkers, drugs or pharmaceutical small molecules.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Técnicas Eletroquímicas , Limite de Detecção , SARS-CoV-2 , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , SARS-CoV-2/isolamento & purificação , Humanos , Glicoproteína da Espícula de Coronavírus/análise , COVID-19/diagnóstico , Desenho de Equipamento , Calibragem , Betacoronavirus/isolamento & purificação , Temperatura Baixa , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Pandemias
2.
Nat Commun ; 15(1): 7131, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39164277

RESUMO

Organic nitrates, as effective donors of the signaling molecule nitric oxide, are widely applied in the pharmaceutical industry. However, practical and efficient methods for accessing organic nitrates are still scarce, and achieving high regiocontrol in unactivated alkene difunctionalization remains challenging. Here we present a simple and practical method for highly regioselective halonitrooxylation of unactivated alkenes. The approach utilizes TMSX (X: Cl, Br, or I) and oxybis(aryl-λ3-iodanediyl) dinitrates (OAIDN) as sources of halogen and nitrooxy groups, with 0.5 mol % FeCl3 as the catalyst. Remarkably, high regioselectivity in the halonitrooxylation of aromatic alkenes can be achieved even without any catalyst. This protocol features easy scalability and excellent functional group compatibility, providing a range of ß-halonitrates (127 examples, up to 99% yield, up to >20:1 rr). Notably, 2-iodoethyl nitrate, a potent synthon derived from ethylene, reacts smoothly with a variety of functional units to incorporate the nitrooxy group into the desired molecules.

3.
Macromol Rapid Commun ; : e2400493, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39150331

RESUMO

Recently, renewable bio-based materials have received more and more attention due to environmental issues such as global warming and ecosystem destruction. In the present work, a series of isosorbide-based bioelastomers poly(isosorbide carbonate-co-butanediol aliphatic esters)s (PICBAs) are synthesized by a facile and economical two-step melt polycondensation. Due to the slightly self-crosslinking reaction of isosorbide, PICBAs exhibit excellent tensile strength and self-healing ability, the mechanical properties of PICBAs can recover over 95% after 48 h under room temperature. In addition, PICBAs can stick different substances, such as glass, rubber, plastic, and stones, and show better adhesive performance than 3M commercially available double-sided tape. Consequently, isosorbide-based bioelastomers PICBAs are of great potential to be used as environmentally friendly pressure-sensitive adhesives (PSA) in the future.

4.
Fitoterapia ; 177: 106073, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38897246

RESUMO

In our continuous work on the isolation of endophytes, the endophytic fungal strain YIMF00209 was obtained from the roots of Gmelina arborea, which is an ethnic medicinal plant mainly distributed in Southeast Asia. The fermentation extracts of the strain exhibited significant antimicrobial activities against Staphylococcus aureus, Fusarium solani, and Escherichia coli. Based on morphological characteristics and phylogenetic analysis, it was identified as Talaromyces muroii. Four new polyketides, talaromurolides A-D (1-4), along with 26 known compounds (5-30), were isolated from the culture broth of the strain in two different media. Their structures were identified based on HRESIMS, NMR, and CD spectral data. Among them, compounds 2, 4-6, 19, 22, 24, 27, 28, and 30 were isolated from the fermentation broth in CYM medium; compounds 1, 3, 7-18, 20, 21, 23, 25, 26, and 29 were obtained from the fermentation broth in PDB medium; and compounds 2, 5, and 30 were existed in both two media. Compounds 6-9, 12, 16, 20, 21, 23, 25, and 29 were obtained from the genus Talaromyces for the first time. The antimicrobial activities of several compounds were assayed against six pathogens. Compound 1 exhibited inhibitory activities against S. aureus, E. coli, Candida albicans, Salmonella typhimurium, and Botrytis cinerea with MIC value of 64 µg/mL. Compound 25 exhibited antibacterial activity against E. coli with MIC value of 32 µg/mL.


Assuntos
Endófitos , Policetídeos , Staphylococcus aureus , Talaromyces , Policetídeos/farmacologia , Policetídeos/isolamento & purificação , Policetídeos/química , Endófitos/química , Estrutura Molecular , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Fusarium/efeitos dos fármacos , Raízes de Plantas/microbiologia , Filogenia , Antibacterianos/farmacologia , Antibacterianos/isolamento & purificação
5.
Nat Commun ; 15(1): 4919, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858346

RESUMO

Chiral 1,2,3-triazoles are highly attractive motifs in various fields. However, achieving catalytic asymmetric click reactions of azides and alkynes for chiral triazole synthesis remains a significant challenge, mainly due to the limited catalytic systems and substrate scope. Herein, we report an enantioselective azidation/click cascade reaction of N-propargyl-ß-ketoamides with a readily available and potent azido transfer reagent via copper catalysis, which affords a variety of chiral 1,2,3-triazoles with up to 99% yield and 95% ee under mild conditions. Notably, chiral 1,5-disubstituted triazoles that have not been accessed by previous asymmetric click reactions are also prepared with good functional group tolerance.

6.
J Formos Med Assoc ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38702216

RESUMO

The purpose of this study is to establish a deep learning automatic assistance diagnosis system for benign and malignant classification of mediastinal lesions in endobronchial ultrasound (EBUS) images. EBUS images are in the form of video and contain multiple imaging modes. Different imaging modes and different frames can reflect the different characteristics of lesions. Compared with previous studies, the proposed model can efficiently extract and integrate the spatiotemporal relationships between different modes and does not require manual selection of representative frames. In recent years, Vision Transformer has received much attention in the field of computer vision. Combined with convolutional neural networks, hybrid transformers can also perform well on small datasets. This study designed a novel deep learning architecture based on hybrid transformer called TransEBUS. By adding learnable parameters in the temporal dimension, TransEBUS was able to extract spatiotemporal features from insufficient data. In addition, we designed a two-stream module to integrate information from three different imaging modes of EBUS. Furthermore, we applied contrastive learning when training TransEBUS, enabling it to learn discriminative representation of benign and malignant mediastinal lesions. The results show that TransEBUS achieved a diagnostic accuracy of 82% and an area under the curve of 0.8812 in the test dataset, outperforming other methods. It also shows that several models can improve performance by incorporating two-stream module. Our proposed system has shown its potential to help physicians distinguishing benign and malignant mediastinal lesions, thereby ensuring the accuracy of EBUS examination.

7.
Biomed Pharmacother ; 173: 116262, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38394845

RESUMO

BACKGROUND: The glucose derivative 3-O-methyl-D-glucose (OMG) is used as a cryoprotectant in freezing cells. However, its protective role and the related mechanism in static cold storage (CS) of organs are unknown. The present study aimed to investigate the effect of OMG on cod ischemia damage in cold preservation of donor kidney. METHODS: Pretreatment of OMG on kidney was performed in an isolated renal cold storage model in rats. LDH activity in renal efflux was used to evaluate the cellular damage. Indicators including iron levels, mitochondrial damage, MDA level, and cellular apoptosis were measured. Kidney quality was assessed via a kidney transplantation (KTx) model in rats. The grafted animals were followed up for 7 days. Ischemia reperfusion (I/R) injury and inflammatory response were assessed by biochemical and histological analyses. RESULTS: OMG pretreatment alleviated prolonged CS-induced renal damage as evidenced by reduced LDH activities and tubular apoptosis. Kidney with pCS has significantly increased iron, MDA, and TUNEL+ cells, implying the increased ferroptosis, which has been partly inhibited by OMG. OMG pretreatment has improved the renal function (p <0.05) and prolonged the 7-day survival of the grafting recipients after KTx, as compared to the control group. OMG has significantly decreased inflammation and tubular damage after KTx, as evidenced by CD3-positive cells and TUNEL-positive cells. CONCLUSION: Our study demonstrated that OMG protected kidney against the prolonged cold ischemia-caused injuries through inhibiting ferroptosis. Our results suggested that OMG might have potential clinical application in cold preservation of donor kidney.


Assuntos
Ferroptose , Traumatismo por Reperfusão , Ratos , Animais , 3-O-Metilglucose/farmacologia , Isquemia Fria/efeitos adversos , Preservação de Órgãos/métodos , Rim , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/patologia , Isquemia/patologia , Ferro
8.
Anal Chim Acta ; 1275: 341583, 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37524467

RESUMO

An ultrasensitive electrochemical biosensor for detecting p53 gene was fabricated based on heated gold disk electrode coupling with endonuclease Nt.BstNBI-assisted target recycle amplification and alkaline phosphatase (ALP)-based electrocatalytic signal amplification. For biosensor assembling, biotinylated ssDNA capture probes were first immobilized on heated Au disk electrode (HAuDE), then combined with streptavidin-alkaline phosphatase (SA-ALP) by biotin-SA interaction. ALP could catalyze the hydrolysis of ascorbic acid 2-phosphate (AAP) to produce ascorbic acid (AA). While AA could induce the redox cycling to generate electrocatalytic oxidation current in the presence of ferrocene methanol (FcM). When capture probes hybridized with p53, Nt.BstNBI would recognize and cleave the duplexes and p53 was released for recycling. Meanwhile, the biotin group dropt from the electrode surface and subsequently SA-ALP could not adhere to the electrode. The signal difference before and after cleavage was proportional to the p53 gene concentration. Furthermore, with electrode temperature elevated, the Nt.BstNBI and ALP activities could be increased, greatly improving the sensitivity and efficiency for p53 detection. A detection limit of 9.5 × 10-17 M could be obtained (S/N = 3) with an electrode temperature of 40 °C, ca. four magnitudes lower than that at 25 °C.


Assuntos
Técnicas Biossensoriais , Biotina , Fosfatase Alcalina/metabolismo , Técnicas Eletroquímicas , Ouro , Calefação , Endonucleases , Proteína Supressora de Tumor p53/genética , Genes p53 , Eletrodos , Limite de Detecção
9.
Chem Commun (Camb) ; 59(50): 7831-7834, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37272849

RESUMO

Copper-catalyzed asymmetric dearomative azidation of tryptamines using azidobenziodoxolone as an azidating reagent was developed, which affords a variety of 3a-azido-pyrroloindolines in good to high enantioselectivities under mild reaction conditions. The azides could be readily transformed into the corresponding 3a-amino-pyrroloindolines via reduction and 1,2,3-triazole derivatives via a click reaction.

10.
Huan Jing Ke Xue ; 44(5): 2829-2837, 2023 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-37177954

RESUMO

The purpose of this study was to explore the distribution characteristics and potential ecological risks of soil heavy metal pollution of cultivated land under non-grain production. Taking a typical area around Hangzhou Bay as an example, 254 topsoil samples (0-20 cm) of cultivated land were collected, and the content of eight soil heavy metals in four different cultivated land use types, including grain, seedlings, vegetables, and fruits, was analyzed. The ecological risk was assessed by the Nemerow pollution index and the potential ecological risk index, and the PMF model was used to identify the source of soil heavy metals in the study area. The results showed that the average contents of As, Cr, Cd, Cu, Hg, Ni, and Zn were all higher than the soil background value, except for Pb, but were lower than the national risk control standard for soil contamination of agricultural land. Non-grain production had a significant impact on the accumulation of heavy metals in soil. The content of heavy metals in nurseries and orchards was relatively high, followed by vegetable fields, and the lowest in grain fields. The Nemerow index showed that the cultivated land in the study area was in a light pollution level as a whole, and the single-factor pollution risks of Hg, Cd, and As were relatively high. The potential ecological risk levels of heavy metals in different cultivated land use types were:nurseries>orchards>vegetable fields>grain fields. The PMF results showed that the main sources of soil heavy metals in the study area were mixed sources of industrial emissions (36.8%), natural parent material sources (28.4%), atmospheric deposition sources (21.4%), and agricultural activity sources (13.4%). In conclusion, the increase in the application of chemical fertilizers and pesticides was the direct reason for the increase in soil heavy metal content caused by non-grain production of the cultivated land, whereas the industrial and mining emissions and atmospheric deposition accelerated the increase in soil heavy metal content in the study area.

11.
Gels ; 8(11)2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36354624

RESUMO

The phase diagram of a given polymer solution is used to determine the solution's electrospinnability. We constructed a phase diagram of an aqueous solution of atactic poly(N-isopropylacrylamide) (a-PNIPAM) based on turbidity measurements and the rheological properties derived from linear viscoelasticity. Several important transition temperatures were obtained and discussed, including the onset temperature for concentration fluctuations T1, gel temperature Tgel, and binodal temperature Tb. On heating from 15 °C, the one-phase a-PNIPAM solution underwent pronounced concentration fluctuations at temperatures above T1. At higher temperatures, the thermal concentration fluctuations subsequently triggered the physical gelation process to develop a macroscopic-scale gel network at Tgel before the phase separation at Tb. Thus, the temperature sequence for the transition is: T1 < Tgel < Tb~31 °C for a given a-PNIPAM aqueous solution. Based on the phase diagram, a low-temperature electrospinning process was designed to successfully obtain uniform a-PNIPAM nanofibers by controlling the solution temperature below T1. In addition, the electrospinning of an a-PNIPAM hydrogel at Tgel < T < Tb was found to be feasible considering that the elastic modulus of the gel was shown to be very low (ca. 10−20 Pa); however, at the jet end, jet whipping was not seen, though the spitting out of the internal structures was observed with high-speed video. In this case, not only dried nanofibers but also some by-products were produced. At T > Tb, electrospinning became problematic for the phase-separated gel because the enhanced gel elasticity dramatically resisted the stretching forces induced by the electric field.

12.
Fitoterapia ; 162: 105297, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36096278

RESUMO

Two new nucleoside derivatives, kipukasins O (1) and P (2), one new cyclohexenone derivative, arthropsadiol D (5), and one new natural product, (+)-2,5-dimethyl-3(2H)-benzofuranone (6), together with eleven known compounds (3, 4, 7-15), were obtained from the culture broth of the endophytic fungus Aspergillus polyporicola R2 isolated from the roots of Synsepalum dulcificum. Among them, the absolute configuration of compound 5 was determined by quantum chemical calculations of NMR chemical shifts and ECD spectrum. The antimicrobial activities of these compounds were evaluated. Compound 11 exhibited obvious inhibitory activity against MRSA, Staphylococcus aureus, Salmonella typhimurium, Botrytis cinerea, and Fusarium graminearum with MIC values of 4, 4, 4, 32, and 16 µg/mL, respectively. Compound 12 exhibited antibacterial activity against S. typhimurium and MRSA with MIC values of 4 and 16 µg/mL. Compound 6 exhibited antifungal activity against F. graminearum with MIC value of 32 µg/mL.


Assuntos
Anti-Infecciosos , Produtos Biológicos , Antibacterianos , Anti-Infecciosos/farmacologia , Antifúngicos , Aspergillus , Testes de Sensibilidade Microbiana , Estrutura Molecular , Nucleosídeos
13.
Front Oncol ; 12: 975859, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36132144

RESUMO

Objective: To systematically analyze the expression of cuproptosis and ferroptosis genes and their impact on the development, prognosis, tumor microenvironment (TME), and treatment response in colorectal cancer (CRC) patients. Methods: We systematically evaluated 33 cuproptosis and ferroptosis-related genes and comprehensively identified the correlations between cuproptosis and ferroptosis-related genes and transcriptional patterns, prognosis, and clinical features. Three distinct subgroups were identified in CRC using the TCGA database and the GEO database. We next assessed the relationship between the molecular features, prognostic significance, and clinical indicators of the prognostic genes in the cuproptosis and ferroptosis-related gene clusters. In addition, a PAC_score, which accurately predicted the prognosis of CRC patients and the efficacy of immunomodulatory mAbs, was obtained. Results: Patients in the low expression group (low expression of cuproptosis and ferroptosis-related genes) had a longer survival compared to the high expression group. We identified two distinct prognosis-associated molecular subtypes and observed an association between clinical information and prognosis. The enrichment analysis of differential genes associated with prognosis showed that the main enrichment was related to biological processes such as metastasis and metabolism. Next, the PCA_score for predicting overall survival (OS) was established and its reliable predictive value in CRC patients was confirmed. Furthermore, highly reliable nomogram was created to facilitate the clinical feasibility of the PCA_score. It was found that the immunomodulatory mAbs, PD-L1 and CTLA4 were highly expressed in the low PCA_score score group with statistically significance. Conclusion: Overall, the PCA scores of prognostic differential genes in the cuproptosis and ferroptosis-related gene clusters were strongly associated with clinical characteristics, prognosis, and immunotherapy in CRC patients. This data may promote further exploration of more effective immunotherapy strategies for CRC.

14.
Biosens Bioelectron ; 210: 114283, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35447396

RESUMO

In this work, a novel "turn-on" mode Au nanocubes (AuNCs) enhanced surface-enhanced Raman scattering (SERS) biosensing platform coupled with heated Au electrode (HAuE) and strand displacement amplification (SDA) strategy was proposed for highly sensitive detection of DNA adenine methylation (Dam) Methyltransferase (MTase) activity. The Dam MTase and DpnI enzyme activities were significantly increased by elevating the HAuE surface temperature, resulting in the rapid production of template DNA for later SDA. During the SDA process, the released single-stranded DNA (ssDNA) could be amplified exponentially, and its concentration was positively related to the Dam MTase activity. The plasmonic AuNCs in SERS tags could provide significant SERS enhancement due to their "lightning rod" effect resulting from the sharp feature of the edges and corners of AuNCs. Because of these factors, the proposed biosensors exhibited high sensitivity in detecting the Dam MTase activity. The limit of detection was estimated to be 8.65 × 10-5 U mL-1, which was lower than that in most of the sensors for detection of Dam MTase activity in the literature. This SERS biosensor could also be used to screen inhibitors of Dam MTase and had the potential for detecting Dam MTase activity in real biological samples.


Assuntos
Técnicas Biossensoriais , Técnicas Biossensoriais/métodos , Metilação de DNA , DNA de Cadeia Simples , Eletrodos , DNA Metiltransferases Sítio Específica (Adenina-Específica)
15.
Phytochemistry ; 199: 113188, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35421432

RESUMO

The investigation of the metabolites from the endophytic fungus Xylaria sp. YM 311647 in solid fermentation resulted in the isolation of six undescribed compounds, namely xylarioxides A-F, respectively. These included one eremophilane sesquiterpene, three guaiane sesquiterpene glycosides, and two ergostane glycosides. The structures of the compounds were determined by extensive analyses of spectroscopic data, including 1D and 2D NMR, as well as HRESIMS data. The stereochemistry of xylarioxide A was confirmed by X-ray crystallographic analysis. All of the isolated compounds were assayed for their antifungal activities against seven phytopathogenic fungi and two human pathogenic fungi. Among them, xylarioxides A, E and F showed potent activities against the tested phytopathogens. Particularly, xylarioxide E exhibited the highest activity against Gibberella saubinetii, Curvularia lunata, and Colletotrichum gloeosporioides with MIC values of 4, 4, and 8 µg/mL, respectively, which were comparable to the positive control of nystatin. Interestingly, guaiane sesquiterpene glycosides have been rarely reported from fungal sources. Additionally, xylarioxide E represented an unusual naturally occurring 3,4-seco-steroidal glycoside with a seven-membered lactone in ring A.


Assuntos
Azadirachta , Sesquiterpenos , Xylariales , Ergosterol/análogos & derivados , Glicosídeos/farmacologia , Estrutura Molecular , Sesquiterpenos/química , Sesquiterpenos de Guaiano/química , Xylariales/química
16.
J Am Chem Soc ; 143(35): 14218-14226, 2021 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-34432466

RESUMO

Skyrin and rugulosin A are bioactive bisanthraquinones found in many fungi, with the former suggested as a precursor of hypericin (a diversely bioactive phytochemical) and the latter characterized by its distinct cage-like structure. However, their biosynthetic pathways remain mysterious, although they have been characterized for over six decades. Here, we present the rug gene cluster that governs simultaneously the biosynthesis of skyrin and rugulosin A in Talaromyces sp. YE3016, a fungal endophyte residing in Aconitum carmichaeli. A combination of genome sequencing, gene inactivation, heterologous expression, and biotransformation tests allowed the identification of the gene function, biosynthetic precursor, and enzymatic sets involved in their molecular architecture constructions. In particular, skyrin was demonstrated to form from the 5,5'-dimerization of emodin radicals catalyzed by RugG, a cytochrome P450 monooxygenase evidenced to be potentially applicable for the (chemo)enzymatic synthesis of dimeric polyphenols. The fungal aldo-keto reductase RugH was shown to be capable of hijacking the closest skyrin precursor (CSP) immediately after the emodin radical coupling, catalyzing the ketone reduction of CSP to inactivate its tautomerization into skyrin and thus allowing for the spontaneous intramolecular Michael addition to cyclize the ketone-reduced form of CSP into rugulosin A, a representative of diverse cage-structured bisanthraquinones. Collectively, the work updates our understanding of bisanthraquinone biosynthesis and paves the way for synthetic biology accesses to skyrin, rugulosin A, and their siblings.


Assuntos
Antraquinonas/metabolismo , Aldo-Ceto Redutases/genética , Aldo-Ceto Redutases/metabolismo , Aspergillus oryzae/genética , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Família Multigênica , Talaromyces/genética , Talaromyces/metabolismo
17.
Microorganisms ; 9(2)2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33494367

RESUMO

The genus Diaporthe and its anamorph Phomopsis are distributed worldwide in many ecosystems. They are regarded as potential sources for producing diverse bioactive metabolites. Most species are attributed to plant pathogens, non-pathogenic endophytes, or saprobes in terrestrial host plants. They colonize in the early parasitic tissue of plants, provide a variety of nutrients in the cycle of parasitism and saprophytism, and participate in the basic metabolic process of plants. In the past ten years, many studies have been focused on the discovery of new species and biological secondary metabolites from this genus. In this review, we summarize a total of 335 bioactive secondary metabolites isolated from 26 known species and various unidentified species of Diaporthe and Phomopsis during 2010-2019. Overall, there are 106 bioactive compounds derived from Diaporthe and 246 from Phomopsis, while 17 compounds are found in both of them. They are classified into polyketides, terpenoids, steroids, macrolides, ten-membered lactones, alkaloids, flavonoids, and fatty acids. Polyketides constitute the main chemical population, accounting for 64%. Meanwhile, their bioactivities mainly involve cytotoxic, antifungal, antibacterial, antiviral, antioxidant, anti-inflammatory, anti-algae, phytotoxic, and enzyme inhibitory activities. Diaporthe and Phomopsis exhibit their potent talents in the discovery of small molecules for drug candidates.

18.
Molecules ; 25(21)2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33153224

RESUMO

Flavonoids and isoflavonoids are polyphenolic secondary metabolites usually produced by plants adapting to changing ecological environments over a long period of time. Therefore, their biosynthesis pathways are considered as the most distinctive natural product pathway in plants. Seemingly, the flavonoids and isoflavones from fungi and actinomycetes have been relatively overlooked. In this review, we summarized and classified the isoflavones and flavonoids derived from fungi and actinomycetes and described their biological activities. Increasing attention has been paid to bioactive substances derived from microorganism whole-cell biotransformation. Additionally, we described the utilization of isoflavones and flavonoids as substrates by fungi and actinomycetes for biotransformation through hydroxylation, methylation, halogenation, glycosylation, dehydrogenation, cyclisation, and hydrogenation reactions to obtain rare and highly active biofunctional derivatives. Overall, among all microorganisms, actinomycetes are the main producers of flavonoids. In our review, we also summarized the functional genes involved in flavonoid biosynthesis.


Assuntos
Actinobacteria/metabolismo , Flavonas/metabolismo , Fungos/metabolismo , Isoflavonas/metabolismo , Biotransformação
19.
ACS Sens ; 5(8): 2636-2643, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32786384

RESUMO

The "turn-on" mode surface-enhanced Raman scattering (SERS) aptasensor for ultrasensitive ochratoxin A (OTA) detection was developed based on the SERS "hot spots" of AuNanostar@4-MBA@Au core-shell nanostructures (AuNS@4-MBA@Au) and exonuclease III (Exo III)-assisted target cycle amplification strategy. Compared with conventional gold nanoparticles, AuNS@4-MBA@Au provides a much higher SERS enhancement factor because AuNS exhibits a larger surface roughness and the lightning rod effect, as well as an excellent electromagnetic field between the AuNS core and the Au shell, which contribute to the superstrong SERS signal. Meanwhile, Exo III-assisted target cycle amplification can be used as an effective method for the further amplified detection of OTA. Additionally, the utilization of streptavidin magnesphere paramagnetic particles offers a green, economical, and facile technology for the accumulation and separation of the signal probe AuNS@4-MBA@Au from solution. All these factors lead to a significant enhancement of detectable signals and superhigh sensitivity. As a result, the limit of detection as low as 0.25 fg mL-1 could be achieved, which was lower than that in the other reported literatures on SERS methods for OTA detection as we know. The developed SERS aptasensor also provides a promising tool for foodstuff detection.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Exodesoxirribonucleases , Ouro , Ocratoxinas , Prata , Compostos de Sulfidrila
20.
Food Chem ; 322: 126738, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32283361

RESUMO

Quality characteristics of whole wheat flour with superheated steam treatment and storage stability of semi-dried whole wheat noodle were investigated, as well as texture and cooking properties of cooking noodles. Superheated steam treatment significantly reduced the total plate count and the activities of lipase, lipoxygenase and polyphenol oxidase in whole wheat flour (p < 0.05), and decreased the free phenolic content. When treated at 155-170 °C, the thermomechanical properties of whole wheat dough improved with the increase of the development time, stability and C2 torque. Superheated steam treatment showed no obviously detrimental effects on hardness and cooking loss of noodle. During storage, treated semi-dried whole wheat noodle exhibited slower rate of microbial growth. Superheated steam treatment significantly reduced the acidity, inhibited the formation of free fatty acid, and decreased the activities of enzyme during storage. This would delay the deterioration and improve the storage stability of semi-dried whole wheat noodle.


Assuntos
Culinária , Farinha/análise , Armazenamento de Alimentos , Triticum/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Dureza , Temperatura Alta , Concentração de Íons de Hidrogênio , Lipase/metabolismo , Lipoxigenase/metabolismo , Fenol/análise , Paladar
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