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1.
Beilstein J Org Chem ; 20: 815-822, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655553

RESUMO

Drimane-type sesquiterpenoids (DMTs) are characterized by a distinctive 6/6 bicyclic skeleton comprising the A and B rings. While DMTs are commonly found in fungi and plants, their presence in bacteria has not been reported. Moreover, the biosynthetic pathways for DMTs have been primarily elucidated in fungi, with identified P450s only acting on the B ring. In this study, we isolated and characterized three bacterial DMTs, namely 3ß-hydroxydrimenol (2), 2α-hydroxydrimenol (3), and 3-ketodrimenol (4), from Streptomyces clavuligerus. Through genome mining and heterologous expression, we identified a cav biosynthetic gene cluster responsible for the biosynthesis of DMTs 2-4, along with a P450, CavA, responsible for introducing the C-2 and C-3 hydroxy groups. Furthermore, the substrate scope of CavA revealed its ability to hydroxylate drimenol analogs. This discovery not only broadens the known chemical diversity of DMTs from bacteria, but also provides new insights into DMT biosynthesis in bacteria.

2.
Angew Chem Int Ed Engl ; : e202401669, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38651244

RESUMO

cis-Prenyltransferases (cis-PTs) catalyze the sequential head-to-tail condensation of isopentenyl diphosphate (IPP) to allylic diphosphates, producing mixed E-Z prenyl diphosphates of varying lengths; yet, the specific enzymes synthesizing cis-C25 prenyl diphosphates have not been identified. In this study, we present the discovery and characterization of a cis-geranylfarnesyl diphosphate synthase (ScGFPPS) from Streptomyces clavuligerus. This enzyme demonstrates high catalytic proficiency in generating six distinct cis-polyisoprenoids, including three C25 and three C20 variants. We further determine the crystal structure of ScGFPPS. Additionally, we unveil the crystal structure of nerylneryl diphosphate synthase (NNPS), known for synthesizing an all-cis-C20 polyisoprenoid. Comparative structural analysis of ScGFPPS and NNPS has identified key differences that influence product specificity. Through site-directed mutagenesis, we have identified eight single mutations that significantly refine ScGFPPS's selectivity for cis-polyisoprenoids. Our findings not only expand the functional spectrum of cis-PTs but also provide a structural comparison strategy in cis-PTs engineering.

4.
Bioorg Chem ; 146: 107308, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38531151

RESUMO

Genome mining of the Actinomycete Crossiella cryophila facilitated the discovery of a minimal terpenoid biosynthetic gene cluster of cry consisting of a class I terpene cyclase CryA and a CYP450 monooxygenase CryB. Heterologous expression of cry allowed the isolation and characterization of two new sesquiterpenoids, ent-viridiflorol (1) and cryophilain (2). Notably, cryophilain (2) possesses a 5/7/3-fused tricyclic skeleton bearing a distinctive bridgehead hydroxy group. The combined in vivo and in vitro experiments revealed that CryA, the first ent-viridiflorol terpene cyclase, catalyzes farnesyl diphosphate to form the 5/7/3 sesquiterpene core scaffold and P450 CryB serves as a tailoring enzyme responsible for installing a hydroxy group at the bridgehead carbon.


Assuntos
Actinobacteria , Actinomycetales , Sesquiterpenos , Terpenos , Sesquiterpenos/metabolismo , Actinobacteria/genética , Actinobacteria/metabolismo , Actinomycetales/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo
5.
Org Lett ; 26(8): 1640-1644, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38382064

RESUMO

In this study, we constructed a taxadiene overproduction platform and identified a cytochrome P450, CYP701A8, that activates the inert C-H bonds in taxadiene to produce three oxidized products (1-3). Compound 1 possesses a newly identified 1 (15→11) abeotaxane skeleton, while 3 features a distinctive 6/10-fused carbocyclic core with an α,ß-unsaturated ketone moiety. Our quantum computations suggested a carbocation-driven rearrangement in the formation of 1. These results support CYP701A8 as a promising biocatalyst for the generation of novel taxane diterpenoids.


Assuntos
Alcenos , Diterpenos , Esqueleto , Sistema Enzimático do Citocromo P-450/genética , Compostos Radiofarmacêuticos , Escherichia coli/genética
6.
Inorg Chem ; 63(8): 3702-3711, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38335057

RESUMO

A long-term goal of rechargeable zinc-air batteries (ZABs) has always been to design bifunctional electrocatalysts that are robust, effective, and affordable for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). It has become a feasible method to construct metal/metal oxide interfaces to achieve superior electrocatalytic performance for ORR and OER by enhanced charge transfer. In this study, Co/Co3O4 heterojunctions were successfully prepared and encased in porous N-doped mesoporous carbon (Co/Co3O4@NC) via a simple condensation-carbonization-etching method. The extensive specific surface area of Co/Co3O4@NC facilitates effective interaction between the electrolyte and the catalyst, thereby enabling sufficient exposure of active sites for the ORR and the OER, consequently enhancing the rate of transport of active species. The well-designed Co/Co3O4@NC delivers superior ORR catalytic activity with a half-wave potential of 0.82 V (vs RHE) and a low overpotential of 347 mV at 10 mA cm-2 for OER in alkaline solution. The power density of Co/Co3O4@NC-based alkaline aqueous ZAB (156.5 mW cm-2) is superior to the commercial Pt/C + IrO2-based alkaline aqueous ZAB, and the cycling stability of ZAB is up to 220 h. In addition, Co/Co3O4@NC-based ZAB shows a high power density (50.1 mW cm-2). The construction of metal/metal oxide heterojunction encased in N-doped mesoporous carbon provides a novel route for the design of bifunctional electrocatalysts for high-performance ZABs.

7.
J Nat Prod ; 87(2): 195-206, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38266176

RESUMO

Terpenoids, the largest and most structurally diverse natural product family, are predominantly found in fungi and plants, with bacterial terpenoids forming a minor fraction. Here, we established an efficient platform that integrates genome mining and NMR-tracking for prioritizing strains and tracking bacterial terpenoids. By employing this platform, we selected Crossiella cryophila for a comprehensive investigation of its capacity for terpenoid production, resulting in the characterization of 15 sesquiterpenoids. These compounds comprise nine new sesquiterpenoids (1-9), along with six known analogs (10-15), which are categorized into five distinctive carbon skeletons: bicyclogermacrane, maaliane, cadinane, eudesmane, and nor-eudesmane. Their chemical structures were determined through a combination of spectroscopic analysis, single-crystal X-ray diffraction, and quantum chemical calculations. Notably, the absolute configurations of compounds 1, 2, 5-7, 9, and 13-15 were determined via single-crystal X-ray diffraction analyses. The selected compounds were evaluated for their anticancer, antimicrobial, and anti-inflammatory bioactivities; however, none of these compounds displayed any significant bioactivity. This study enriches the repertoire of bacterial terpenoids, offers a practical process for prioritizing strains for bacterial terpenoids discovery, and establishes a foundation for exploring terpenoid biosynthesis.


Assuntos
Actinobacteria , Sesquiterpenos de Eudesmano , Sesquiterpenos , Sesquiterpenos/química , Terpenos/química , Anti-Inflamatórios , Estrutura Molecular
8.
J AOAC Int ; 107(1): 158-163, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-37531289

RESUMO

BACKGROUND: Dendrobium huoshanense (DHS) is a classic traditional Chinese medicine (TCM) with distinctive medicinal benefits and great economic worth; nevertheless, because of similar tastes and looks, it is simple to adulterate with less expensive substitutes (such as Dendrobium henanense [DHN]). OBJECTIVE: This work aimed to develop a reliable tool to detect and quantify the adulteration of DHS with DHN by using UV-Vis-shortwave near-infrared diffuse reflectance spectroscopy (UV-Vis-SWNIR DRS) combined with chemometrics. METHODS: Adulterated samples prepared in varying concentrations (0-100%, w/w) were analyzed with UV-Vis-SWNIR DRS methods. Partial least-square-discriminant analysis (PLS-DA) and partial least-squares (PLS) regression techniques were used for the differentiation of adulterated DHN from pure DHS and the prediction of adulteration levels. RESULTS: The PLS-DA classification models successfully differentiated adulterated and nonadulterated DHS with an over 100% correct classification rate. UV-Vis-SWNIR DRS data were also successfully used to predict adulteration levels with a high coefficient of determination for calibration (0.9924) and prediction (0.9906) models and low error values for calibration (3.863%) and prediction (5.067%). CONCLUSION: UV-Vis-SWNIR DRS, as a fast and environmentally friendly tool, has great potential for both the identification and quantification of adulteration practices involving herbal medicines and foods. HIGHLIGHTS: UV-Vis-SWNIR DRS combined with chemometrics can be applied to identify and quantify the adulteration of herbal medicines and foods.


Assuntos
Dendrobium , Quimiometria , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Análise Discriminante , Análise dos Mínimos Quadrados , Extratos Vegetais , Contaminação de Alimentos/análise
9.
Ecotoxicol Environ Saf ; 268: 115684, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37976935

RESUMO

The extensive use of carbamate pesticides has led to a range of environmental and health problems, such as surface and groundwater contamination, and endocrine disorders in organisms. In this study, we focused on examining the effects of toxic exposure to the carbamate pesticide methomyl on the hatching, morphology, immunity and developmental gene expression levels in zebrafish embryos. Four concentrations of methomyl (0, 2, 20, and 200 µg/L) were administered to zebrafish embryos for a period of 96 h. The study found that exposure to methomyl accelerated the hatching process of zebrafish embryos, with the strongest effect recorded at the concentration of 2 µg/L. Methomyl exposure also trigged significantly reductions in heart rate and caused abnormalities in larvae morphology, and it also stimulated the synthesis and release of several inflammatory factors such as IL-1ß, IL-6, TNF-α and INF-α, lowered the IgM contents, ultimately enhancing inflammatory response and interfering with immune function. All of these showed the significant effects on exposure time, concentration and their interaction (Time × Concentration). Furthermore, the body length of zebrafish exposed to methomyl for 96 h was significantly shorter, particularly at higher concentrations (200 µg/L). Methomyl also affected the expression levels of genes associated with development (down-regulated igf1, bmp2b, vasa, dazl and piwi genes), demonstrating strong developmental toxicity and disruption of the endocrine system, with the most observed at the concentration of 200 µg/L and 96 h exposure to methomyl. The results of this study provide valuable reference information on the potential damage of methomyl concentrations in the environment on fish embryo development, while also supplementing present research on the immunotoxicity of methomyl.


Assuntos
Praguicidas , Poluentes Químicos da Água , Animais , Peixe-Zebra/metabolismo , Metomil/metabolismo , Metomil/farmacologia , Embrião não Mamífero , Sistema Endócrino , Praguicidas/metabolismo , Carbamatos/metabolismo , Larva , Poluentes Químicos da Água/metabolismo
10.
Angew Chem Int Ed Engl ; 62(45): e202312490, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37735947

RESUMO

Terpene cyclization, one of the most complex chemical reactions in nature, is generally catalyzed by two classes of terpene cyclases (TCs). Cytochrome P450s that act as unexpected TC-like enzymes are known but are very rare. In this study, we genome-mined a cryptic bacterial terpenoid gene cluster, named ari, from the thermophilic actinomycete strain Amycolatopsis arida. By employing a heterologous production system, we isolated and characterized three highly oxidized eunicellane derived diterpenoids, aridacins A-C (1-3), that possess a 6/7/5-fused tricyclic scaffold. In vivo and in vitro experiments systematically established a noncanonical two-step biosynthetic pathway for diterpene skeleton formation. First, a class I TC (AriE) cyclizes geranylgeranyl diphosphate (GGPP) into a 6/10-fused bicyclic cis-eunicellane skeleton. Next, a cytochrome P450 (AriF) catalyzes cyclization of the eunicellane skeleton into the 6/7/5-fused tricyclic scaffold through C2-C6 bond formation. Based on the results of quantum chemical computations, hydrogen abstraction followed by electron transfer coupled to barrierless carbocation ring closure is shown to be a viable mechanism for AriF-mediated cyclization. The biosynthetic logic of skeleton construction in the aridacins is unprecedented, expanding the catalytic capacity and diversity of P450s and setting the stage to investigate the inherent principles of carbocation generation by P450s in the biosynthesis of terpenoids.


Assuntos
Diterpenos , Terpenos , Ciclização , Terpenos/química , Sistema Enzimático do Citocromo P-450/metabolismo , Diterpenos/química , Bactérias/metabolismo
11.
Small ; 19(45): e2301130, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37434036

RESUMO

Compared with the traditional electrolysis of water to produce hydrogen, urea-assisted electrolysis of water to produce hydrogen has significant advantages and has received extensive attention from researchers. Unfortunately, urea oxidation reaction (UOR) involves a complex six-electron transfer process leading to high overpotential, which forces researchers to develop high-performance UOR catalysts to drive the development of urea-assisted water splitting. Based on the UOR mechanism and extensive literature research, this review summarizes the strategies for preparing highly efficient UOR catalysts. First, the UOR mechanism is introduced and the characteristics of excellent UOR catalysts are pointed out. Aiming at this, the following modulation strategies are proposed to improve the catalytic performance based on summarizing various literature: 1) Accelerating the active phase formation to reduce initial potential; 2) Creating double active sites to trigger a new UOR mechanism; 3) Accelerating urea adsorption and promoting C─N bond cleavage to ensure the effective conduct of UOR; 4) Promoting the desorption of CO2 to improve stability and prevent catalyst poisoning; 5) Promoting electron transfer to overcome the inherent slow dynamics of UOR; 6) Increasing active sites or active surface area. Then, the application of UOR in electrochemical devices is summarized. Finally, the current deficiencies and future directions are discussed.

12.
Nanoscale ; 15(28): 11777-11800, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37404024

RESUMO

Transition metal nitrides (TMNs) have become excellent substitutes for precious metals such as Pt and Ir in the field of electrocatalysis because of their excellent electrocatalytic performance, high conductivity, good corrosion resistance and stability. As we all know, the commonly utilized carbon-based materials corrode easily during electrocatalysis, which will lead to catalyst falling off and agglomeration. Compared with carbon-based materials, TMNs have stronger corrosion resistance and higher stability. In the metal nitrides, a variety of chemical bonds (metal bond, ionic bond and covalent bond) coexist, among which the ionic bond between metal atoms and nitrogen atoms can make the d-band shrink and narrow, which leads to TMNs having characteristics similar to precious metals in the electrocatalytic process; thus, they can be used as a substitute for precious metal catalysts. In this paper, the synthesis method and catalytic principle of transition metal nitrides and their applications in the fields of hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) are discussed, and the shortcomings of TMNs as a catalyst, the challenges faced in catalyst research and the developments and prospects for the future are pointed out.

13.
World J Clin Cases ; 11(11): 2405-2411, 2023 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-37123309

RESUMO

Translational therapy refers to a combination of chemotherapy, radiotherapy, targeted therapy, and immunotherapy for patients with advanced gastric cancer who are initially unable to undergo R0 resection. This treatment can achieve partial or complete remission of the unresectable tumors to meet the criteria for R0 resection, thus enabling the patients to prolong their survival time and improve their quality of life. In gastric cancer, translational therapy has been tried and improved. At present, there are a large number of patients with locally advanced gastric cancer in China, and the selection of suitable patients for translational therapy to prolong objective survival and improve survival quality is one of the hot spots in the field of gastric cancer research.

14.
Front Microbiol ; 14: 989162, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937259

RESUMO

Introduction: Evidence suggests that negative cognitive processing bias (NCPB) is a significant risk factor for depression. The microbiota-gut-brain axis has been proven to be a contributing factor to cognitive health and disease. However, the connection between microbiota and NCPB remains unknown. This study mainly sought to explore the key microbiota involved in NCPB and the possible pathways through which NCPB affects depressive symptoms. Methods: Data in our studies were collected from 735 Chinese young adults through a cross-sectional survey. Fecal samples were collected from 35 young adults with different levels of NCPB (18 individuals were recruited as the high-status NCPB group, and another 17 individuals were matched as the low-status NCPB group) and 60 with different degrees of depressive symptoms (27 individuals were recruited into the depressive symptom group, as D group, and 33 individuals were matched into the control group, as C group) and analyzed by the 16S ribosomal RNA sequencing technique. Results: As a result, the level of NCPB correlated with the degree of depressive symptoms as well as anxiety symptoms and sleep quality (p < 0.01). The ß-diversity of microbiota in young adults was proven to be significantly different between the high-status NCPB and the low-status NCPB groups. There were several significantly increased bacteria taxa, including Dorea, Christensenellaceae, Christe -senellaceae_R_7_group, Ruminococcaceae_NK4A214_group, Eggerthellaceae, Family-XIII, Family_XIII_AD3011_group, Faecalibaculum, and Oscillibacter. They were mainly involved in pathways including short-chain fatty acid (SCFA) metabolism. Among these variable bacteria taxa, Faecalibaculum was found associated with both NCPB and depressive symptoms. Furthermore, five pathways turned out to be significantly altered in both the high-status NCPB group and the depressive symptom group, including butanoate metabolism, glyoxylate and dicarboxylate metabolism, propanoate metabolism, phenylalanine, tyrosine, and tryptophan biosynthesis, valine, leucine, and isoleucine degradation. These pathways were related to SCFA metabolism. Discussion: Fecal microbiota is altered in Chinese young male adults with high status NCPB and may be involved in the biochemical progress that influences depressive symptoms.

15.
Chem Commun (Camb) ; 59(27): 3968-3999, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36883557

RESUMO

MXenes are a class of two-dimensional materials with a graphene-like structure, which have excellent optical, biological, thermodynamic, electrical and magnetic properties. Due to the diversity resulting from the combination of transition metals and C/N, the MXene family has expanded to more than 30 members and been applied in many fields with broad application prospects. Among their applications, electrocatalytic applications have achieved many breakthroughs. Therefore, in this review, we summarize the reports on the preparation of MXenes and their application in electrocatalysis published in the last five years and describe the two main methods for the preparation of MXenes, i.e., bottom-up and top to bottom synthesis. Different methods may change the structure or surface termination of MXenes, and accordingly affect their electrocatalytic performance. Furthermore, we highlight the application of MXenes in the electrocatalytic hydrogen evolution reaction (HER), oxygen evolution reaction (OER), oxygen reduction reaction (ORR), carbon dioxide reduction reaction (CO2RR), nitrogen reduction reaction (NRR), and multi-functionalization. It can be concluded that the electrocatalytic properties of MXenes can be modified by changing the type of functional groups or doping. Also, MXenes can be compounded with other materials to produce electronic coupling and improve the catalytic activity and stability of the resulting composites. In addition, Mo2C and Ti3C2 are two types of MXene materials that have been widely studied in the field of electrocatalysis. At present, research on the synthesis of MXenes is focused on carbides, whereas research on nitrides is rare, and there are no synthesis methods meeting the requirements of green, safety, high efficiency and industrialization simultaneously. Therefore, it is very important to explore environmentally friendly industrial production routes and devote more research efforts to the synthesis of MXene nitrides.

16.
Dev Neurobiol ; 82(1): 88-97, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34779143

RESUMO

Interferon regulatory factor-7 (IRF7) is an essential regulator of both innate and adaptive immunity. It is also expressed in the otic vesicle of zebrafish embryos. However, any role for irf7 in hair cell development was uncharacterized. Does it work as a potential deaf gene to regulate hair cell development? We used whole-mount in situ hybridization (WISH) assay and morpholino-mediated gene knockdown method to investigate the role of irf7 in the development of otic vesicle hair cells during zebrafish embryogenesis. We performed RNA sequencing to gain a detailed insight into the molecules/genes which are altered upon downregulation of irf7. Compared to the wild-type siblings, knockdown of irf7 resulted in severe developmental retardation in zebrafish embryos as well as loss of neuromasts and damage to hair cells at an early stage (within 3 days post fertilization). Coinjection of zebrafish irf7 mRNA could partially rescued the defects of the morphants. atp1b2b mRNA injection can also partially rescue the phenotype induced by irf7 gene deficiency. Loss of hair cells in irf7-morphants does not result from cell apoptosis. Gene expression profiles show that, compared to wild-type, knockdown of irf7 can lead to 2053 and 2678 genes being upregulated and downregulated, respectively. Among them, 18 genes were annotated to hair cell (HC) development or posterior lateral line (PLL) development. All results suggest that irf7 plays an essential role in hair cell development in zebrafish, indicating that irf7 may be a member of deafness gene family.


Assuntos
Células Ciliadas Auditivas/citologia , Fator Regulador 7 de Interferon , Proteínas de Peixe-Zebra , Peixe-Zebra , Animais , Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Fator Regulador 7 de Interferon/genética , Fator Regulador 7 de Interferon/metabolismo , Peixe-Zebra/embriologia , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
17.
Front Nutr ; 8: 771078, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34805252

RESUMO

The interchangeable use of different herbs to prepare the same formulation is a common practice in Traditional Chinese Medicine (TCM). However, this practice would require the component herbs to share similar compositions, at least in terms of the bioactive agents, to ensure they can replace each other in drug preparation. In this study, we developed an effective and comprehensive high-performance liquid chromatography-diode array detector (HPLC-DAD) method for simultaneous analysis of 11 phenolic compounds in the methanol extracts of Dendrobium huoshanense, Dendrobium nobile (D. nobile), Dendrobium chrysotoxum (D. chrysotoxum), and Dendrobium fimbriatum (D. fimbriatum), which have been identified as interchangeable ingredients for the same TCM preparation "Shihu" in the Chinese pharmacopeia (ChP). The consistency of the four Dendrobium species was evaluated on the basis of the presence of the 11 investigated compounds and the HPLC fingerprints of the methanol extracts of the plants. When gradient elution was performed with a solvent system of acetonitrile and water on a Zorbax Eclipse XDB-C18 (150 mm × 4.6 mm, 5 µm) with monitoring at 220 nm, all 11 investigated compounds were isolated at the baseline. The established HPLC method showed excellent linearity (all analytical curves showed relative coefficients [R2] > 0.999), sensitivity, precision (relative standard deviation [RSD] < 2%), and accuracy (recovery, 90.65-99.17%). These findings confirmed that the method we constructed was reliable. Quantification analysis showed significant differences in the contents of the investigated polyphenols in the four Dendrobium species. Evaluations of consistency revealed that the similarities among the four species were 0.299-0.906 in assessments based on the 11 polyphenols and 0.685-0.968 in assessments based on HPLC fingerprints. Thus, the components of the four Dendrobium species may be significantly different, and more experiments are required to determine whether they can be used interchangeably in the same amounts for preparing the formulation according to ChP.

18.
J Food Sci ; 86(11): 4828-4839, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34642954

RESUMO

A phenylhexyl isothiocyanate (PITC) precolumn derivatization quantitative analysis of multicomponents by a single marker (QAMS) strategy for the simultaneous analysis of 20 free amino acids (FAA) in Dendrobium huoshanense is proposed. The method was validated by the linearity, limit of detection (LDO), and limit of quantitation (LOQ), recovery, precision, and stability. The results showed that when applying the established method, the LOQ of the FFAs was lower than 1 ng/ml except threonine (1.32 ng) and cysteine (1.16 ng). The QAMS investigation revealed that, using any one of the 20 FAAs as the reference internal standard, no significant differences were observed between the external standard method and the QAMS method for the quantification of FAAs in D. huoshanense by PITC precolumn derivatization [The relative standard deviation (RSD, %) by QAMS and ESM were all below 5%]. HPLC fingerprint investigation combined with similar analysis (the similarity values for S1-S25 were >0.875) and quality fluctuation analysis showed that the cultivation environment might have a great effect on the accumulation of FAAs in D. huoshanense. Overall, our study showed that we might increase the accuracy and scope of the simultaneous quantification of multicomponents using the QAMS technique by being derivatized with a strong UV absorbing group, and QAMS combined with chromatographic fingerprinting can be considered good quality criteria for the quality control of D. huoshanense and may provide analytical technical support for research on Maillard Reaction during the further processing of D. huoshanense.


Assuntos
Dendrobium , Medicamentos de Ervas Chinesas , Aminoácidos , Cromatografia Líquida de Alta Pressão , Controle de Qualidade
19.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(2): 229-234, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-33829696

RESUMO

OBJECTIVE: To investigate the effects of morin-regulated NLRP3/Caspase-1 pathway on experimental autoimmune thyroiditis in rats. METHODS: The rats were randomly assigned to 6 groups: control group, experimental autoimmune thyroiditis group (EAT), low-, medium- and high-dose morin groups (post-modeling gavage of 50, 100 and 200 mg/kg morin hydrate per day for 6 weeks) and tripterygium wilfordii polyglycosides group (LGT group, post-modeling gavage of 6.25 mg/kg tripterygium wilfordii polyglycosidesper day for 6 weeks). Except for the control group, the rat model of experimental autoimmune thyroiditis was established by subcutaneous injection of 0.1 mL incomplete Freund's adjuvant containing porcine thyroglobulin. The levels of serum thyroglobulin (TgAb), thyroid peroxidase antibody (TPOAb), triiodothyronine (T3) and tetraiodothyronine (T4) in serum were detected by radioimmunoassay. The mRNA levels of interleukin-17 ( IL-17), interleukin-4 ( IL-4) and interferon γ ( INF- γ) were detected by reverse transcription-polymerase chain reaction. The levels of serum protein carbonyl content, 8-hydroxydeoxyguanosine (8-OHdG), and malondialdehyde (MDA) activity were checked with test kits. Expressions of NLRP3, apoptosis-related speck-like protein (ASC), and Caspase-1 were detected by Western blot. RESULTS: Compared with the EAT group, serum levels of TPOAb, TgAb, T3, and T4 in low-, medium- and high-dose Morin groups and LGT group were reduced ( P<0.01) and the mRNA levels of IL-17, INF-γ and IL-4 were increased ( P<0.01), the protein hydroxyl content, MDA activity, and 8-OHdG levels were reduced ( P<0.01). The levels of NLRP3, ASC and Caspase-1 were reduced ( P<0.01), the levels of 8-OHdG were significantly reduced ( P<0.01), and the levels of NLRP3, ASC and Caspase-1 were significantly reduced ( P<0.01). There were statistically significant differences between the data from the low-dose and the medium-dose Morin groups and the data of the LGT group ( P<0.05), while data from the high-dose Morin group showed no significant difference compared with the data of the LGT group. Data from low-, medium- and high-dose Morin groups showed no statistically significant differences ( P<0.05). CONCLUSION: The findings suggest that Morin improved experimental autoimmune thyroiditis in rats through regulating NLRP3/Caspase-1 pathway.


Assuntos
Tireoidite Autoimune , Animais , Caspase 1/genética , Caspase 1/metabolismo , Flavonoides , Interleucina-1beta/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Carbonilação Proteica , Ratos , Suínos
20.
Future Microbiol ; 15: 1697-1712, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33350865

RESUMO

Aim: The resident bacterial microbiome may shape and protect the health of vertebrate host. An array of molecules secreted by microbiome may contribute to the ecological stability of the microbiome itself. Material & methods: ELISA, radioactivity, immunofluorescence and cytokines measurements were used to observe the bioactivity and stability of colicin Ia level in oviparous and viviparous animal circulation. Results: Colicin Ia, a protein antimicrobial produced by Escherichia coli, is not present in animals at birth, but increases in concentration with the establishment of a stable gut microbiome and drops when the microbiome is experimentally disrupted. Colicin introduced in vivo is transported to tissues at concentrations able to prevent or eliminate bacterial infection. Conclusion: Our findings suggest an unexpected benefit provided by the presence of a resident microbiome in the form of active, circulating, bacterially-synthesized antimicrobial molecules.


Assuntos
Bactérias/efeitos dos fármacos , Colicinas/farmacologia , Escherichia coli/metabolismo , Microbioma Gastrointestinal , Vertebrados/sangue , Animais , Bactérias/classificação , Bactérias/isolamento & purificação , Bovinos , Colicinas/sangue , Colicinas/metabolismo , Escherichia coli/química , Fezes/microbiologia , Humanos , Coelhos , Vertebrados/microbiologia
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