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1.
Background: So far, no articles have discussed the hypolipidemic effect of wheat germ protein in in vivo experiments. Objective: In this study, we investigated the effects of wheat germ protein (WGP, 300 mg/kg/day) and wheat germ (WG, 300 mg/kg/day) on cholesterol metabolism, antioxidant activities, and serum and hepatic lipids in rats fed a high-fat diet through gavage. Methodology: We used 4-week-old male Wistar 20 rats in our animal experiment. Biochemical indicators of fecal, serum and liver were tested by kits or chemical methods. We also conducted the cholesterol micellar solubility experiment in vitro. Results: After 28 days of treatment, our results showed that WGP significantly reduced the serum levels of total cholesterol (p < 0.05) and nonhigh-density lipoprotein cholesterol (p < 0.05), improved the enzymatic activities of cholesterol 7-α hydroxylase (p < 0.01) and low-density lipoprotein receptor (p < 0.01) and increased bile acid excretion in feces (p < 0.05). Conclusion: WG did not significantly increase bile acid excretion in feces or decrease serum levels of total cholesterol. Moreover, WGP and WG both presented significant antioxidant activity in vivo (p < 0.05) and caused a significant reduction in cholesterol micellar solubility in vitro (p < 0.001). Therefore, WGP may effectively prevent hyperlipidemia and its complications as WGP treatment enhanced antioxidant activity, decreased the concentration of serum lipids and improved the activity of enzymes involved in cholesterol metabolism.  相似文献   

2.
Mononuclear non-heme iron enzymes are a large class of enzymes catalyzing a wide-range of reactions. In this work, we report that a non-heme iron enzyme in Methyloversatilis thermotolerans, OvoAMtht, has two different activities, as a thiol oxygenase and a sulfoxide synthase. When cysteine is presented as the only substrate, OvoAMtht is a thiol oxygenase. In the presence of both histidine and cysteine as substrates, OvoAMtht catalyzes the oxidative coupling between histidine and cysteine (a sulfoxide synthase). Additionally, we demonstrate that both substrates and the active site iron''s secondary coordination shell residues exert exquisite control over the dual activities of OvoAMtht (sulfoxide synthase vs. thiol oxygenase activities). OvoAMtht is an excellent system for future detailed mechanistic investigation on how metal ligands and secondary coordination shell residues fine-tune the iron-center electronic properties to achieve different reactivities.

Modulation of OvoAMtht''s dual activities: sulfoxide synthase and thiol oxygenase.  相似文献   

3.
The structure of the title compound has been determined by a single-crystal, x-ray diffraction study. The compound crystallizes in a monoclinic unit cell (P21/c) with two molecules per unit cell. Least-squared lattice parameters are: a = 7.164 ± 0.001Å, b = 14.770 ± 0.001Å, c = 10.562 ± 0.001Å, and β = 124.95 ± 0.01°. The structure parameters refined to a value of R=0.062, excluding hydrogens, for the 1475 statistically significant reflections. The structure determination confirmed that the compound is indeed a diene and not a delocalized structure. The ring is planar but the ethyl groups extend over the ring in an unusual crab-like fashion.  相似文献   

4.
新型含吡唑基的α-氨基膦酸酯类衍生物的合成及生物活性   总被引:1,自引:0,他引:1  
在微波无溶剂无催化条件下, 以取代吡唑甲醛、芳胺和亚磷酸二乙酯为原料合成了一系列新型含吡唑基的α-氨基膦酸酯类衍生物, 其结构经1H NMR, 13C NMR, MS和31P NMR测试技术进行了表征. 初步生测结果表明, 部分化合物表现出不同程度的抗菌活性.  相似文献   

5.
Kinetic analyses were carried out for formation of disulfide crosslinkages between thiol groups on linear polymers, poly(acrylamide‐coN‐acrylcysteamine) (P‐SH). Disulfide crosslinkages were formed by auto‐oxidation of pendant thiol groups or through the thiol‐disulfide exchange reaction induced by addition of disulfide compounds gluthathione. In the auto‐oxidation reaction, the rate constant for disulfide formation highly depended on pH values of the reaction mixtures and the P‐SH concentrations. Gelation rate is too slow to enclose living cells into hydrogel under physiological pH 7.4. The hydrogel formation rate can be accelerated by addition of disulfides, such as oxidized glutathione. In the later case, oxygen in the reaction mixture is not consumed. The thiol‐disulfide exchange reaction is much more suitable for the cell encapsulation than the thiol auto‐oxidation reaction. These findings give a basis for enclosure of living cells in a hydrogel. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   

6.
In this study, a series of secondary‐ and tertiary‐amino‐substituted diaryl diselenides were synthesized and studied for their glutathione peroxidase (GPx) like antioxidant activities with H2O2, cumene hydroperoxide, or tBuOOH as substrates and with PhSH or glutathione (GSH) as thiol cosubstrates. This study reveals that replacement of the tert‐amino groups in benzylamine‐based diselenides by sec‐amino moieties drastically enhances the catalytic activities in both the aromatic thiol (PhSH) and GSH assay systems. Particularly, the N‐propyl‐ and N‐isopropylamino‐substituted diselenides are 8–18 times more active than the corresponding N,N‐dipropyl‐ and N,N‐diisopropylamine‐based compounds in all three peroxide systems when GSH is used as the thiol cosubstrate. Although the catalytic mechanism of sec‐amino‐substituted diselenides is similar to that of the tert‐amine‐based compounds, differences in the stability and reactivity of some of the key intermediates account for the differences in the GPx‐like activities. It is observed that the sec‐amino groups are better than the tert‐amino moieties for generating the catalytically active selenols. This is due to the absence of any significant thiol‐exchange reactions in the selenenyl sulfides derived from sec‐amine‐based diselenides. Furthermore, the seleninic acids (RSeO2H) derived from the sec‐amine‐based compounds are more stable toward further reactions with peroxides than their tert‐amine‐based analogues.  相似文献   

7.
A search for novel organic luminogens led us to design and synthesize some N‐fused imidazole derivatives based on imidazo[1,2‐a]pyridine as the core and arylamine and imidazole as the peripheral groups. The fluorophores were synthesized through a multicomponent cascade reaction (A3 coupling) of a heterocyclic azine with an aldehyde and alkyne, followed by Suzuki coupling and a multicomponent cyclization reaction. All of the compounds exhibited interesting photophysical responses, especially arylamine‐containing derivatives, which displayed strong positive solvatochromism in the emission spectra that indicated a more polar excited state owing to an efficient charge migration from the donor arylamine to the imidazo[1,2‐a]pyridine acceptor. The quantum yields ranged from 0.2 to 0.7 and depended on the substitution pattern, most notably that based on the donor group at the C2 position. Moreover, the influence of general and specific solvent effects on the photophysical properties of the fluorophores was discussed with four‐parameter Catalán and Kamlet–Taft solvent scales. The excellent thermal, electrochemical, and morphological stability of the compounds was explored by cyclic voltammetry, thermogravimetric analysis, and AFM methods. Furthermore, to understand the structure, bonding, and band gap of the molecules, DFT calculations were performed. The performance of the electroluminescence behavior of the imidazo[1,2‐a]pyridine derivative was investigated by fabricating a multilayer organic light‐emitting diode with a configuration of ITO/NPB (60 nm)/EML (40 nm)/BCP (15 nm)/Alq3 (20 nm)/LiF (0.5 nm)/Al(100 nm) (ITO=indium tin oxide, EML=emissive layer, BCP=2,9‐dimethyl‐4,7‐diphenyl‐1,10‐phenanthroline, Alq3=tris(8‐hydroxyquinolinato)aluminum), which exhibited white emission with a turn‐on voltage of 8 V and a brightness of 22 cd m?2.  相似文献   

8.
The goal of this study was to assess the interest of photodynamic diagnosis (PDD) for laparoscopic detection of peritoneal micro metastasis in ovarian carcinoma. Using an experimental animal model, intraperitoneal injection of aminolevulinic acid (ALA) and hexylester of aminolevulinic acid (He-ALA) were compared in order to improve laparoscopic detection of ovarian peritoneal carcinomatosis. Twenty-one 344 Fischer female rats received an intra peritoneal injection of 106 NuTu-19 cells. At day 22, carcinomatosis with micro peritoneal metastasis was obtained. Rats were randomized in three groups concerning intra peritoneal injection before laparoscopic staging: 5-ALA hydrochloride, HE-ALA and sterile water. Using D Light system, laparoscopic peritoneal exploration was performed with white light (WL) first and then with blue light (BL). The main objective was to assess feasibility and sensibility of laparoscopic PDD for nonvisible peritoneal micro metastasis of ovarian cancer. The main parameter was the confirmation of neoplasic status of fluorescent foci by histology. Concerning PDD after intraperitoneal injection of 5-ALA, mean values of lesions seen is higher than without fluorescence (32 vs 20.7; P = 0.01). Using He-ALA, mean values of detected lesions is higher than without fluorescence (42.9 vs 33.6; P < 0.001). Neoplasic status of fluorescent foci was confirmed in 92.8% of cases (39/42). Using 5-ALA, fluorescence of cancerous tissue is significantly higher than that of normal tissue in all the rats (ratio 1.17) (P = 0.01). With He-ALA, intensity of fluorescence is significantly higher in cancerous tissue compared to normal tissue, irrespective of the rat studied (ratio 1.22; P < 0.001).  相似文献   

9.
The importance of selenium as an essential trace element is now well recognized. In proteins, the redox-active selenium moiety is incorporated as selenocysteine (Sec), the 21st amino acid. In mammals, selenium exerts its redox activities through several selenocysteine-containing enzymes, which include glutathione peroxidase (GPx), iodothyronine deiodinase (ID), and thioredoxin reductase (TrxR). Although these enzymes have Sec in their active sites, they catalyze completely different reactions and their substrate specificity and cofactor or co-substrate systems are significantly different. The antioxidant enzyme GPx uses the tripeptide glutathione (GSH) for the catalytic reduction of hydrogen peroxide and organic peroxides, whereas the larger and more advanced mammalian TrxRs have cysteine moieties in different subunits and prefer to utilize these internal cysteines as thiol cofactors for their catalytic activity. On the other hand, the nature of in vivo cofactor for the deiodinating enzyme ID is not known, although the use of thiols as reducing agents has been well-documented. Recent studies suggest that molecular recognition and effective binding of the thiol cofactors at the active site of the selenoenzymes and their mimics play crucial roles in the catalytic activity. The aim of this perspective is to present an overview of the thiol cofactor systems used by different selenoenzymes and their mimics.  相似文献   

10.
The methylation of a 23-kDa nuclear protein increased after partial hepatectomy and methylation returned to basal levels after the initial stage of regeneration. The methylating enzyme was partially purified from rat liver by ammonium sulfate precipitation, DEAE-anion exchange chromatography and Butyl-Sepharose chromatography. The 23-kDa protein was purified from a nuclear fraction of liver tissue with SP-Sepharose. When the 23-kDa protein was methylated with the partially purified methyltransferase and analyzed on C(18) high performance liquid chromatography (HPLC), the methylated acceptor amino acid was monomethyl lysine (MML). Previously, only arginine N-methylation of specific substrate proteins has been reported during liver regeneration. However, in this report, we found that lysine N-methylation increased during early hepatic regeneration, suggesting that lysine N-methylation of the 23-kDa nuclear protein may play a functional role in hepatic regeneration. The methyltransferase did not methylate other proteins such as histones, hnRNPA1, or cytochrome C, suggesting the enzyme is a 23-kDa nuclear protein- specific lysine N-methyltransferase.  相似文献   

11.
Vinyl- and ethynyl phosphorus(v) electrophiles are a versatile class of thiol-reactive reagents suitable for cysteine-selective peptide and protein modifications, especially for the generation of antibody conjugates. Herein we investigated the reactivity of various P(v) reagents towards thiol addition. Complementing previous studies, we observed that the heteroatoms X (X = S, O, NH) as well as the vinyl- vs. ethynyl-substituent bound to phosphorus greatly influence the overall reactivity. These experimentally observed trends, as well as the high Z-selectivity for thiol additions to ethynyl derivatives, were further elucidated using DFT calculations. Hyperconjugation was a key means of stabilizing the intermediate generated upon the thiol addition, thus determining both the reactivity and stereoselectivity of unsaturated P(v) electrophiles. Specifically, the energetically low-lying σ antibonding orbital of the P–S bond more readily stabilizes the electron density from the lone pair (LP) of the generated carbanion, rendering the phosphonothiolates more reactive compared to the derivatives bearing oxygen and nitrogen. Our studies provide a detailed mechanistic picture for designing P(v)-based electrophiles with fine-tuned reactivity profiles.

Computational analysis of different unsaturated phosphorus(v) electrophiles revealed a mechanistic picture to rationalize their selectivity and reactivity in cysteine-selective peptide and protein modifications.  相似文献   

12.
为探讨乙开型肝炎表面抗原(hepatitis B surface antigen,HBsAg)阳性母亲的婴儿乙肝疫苗注入后早期机体免疫反应的特点,采用化我法测定了吞噬细胞的吞噬功能;用双抗原夹心法测定了抗-HBs抗体。结果表明,(1)乙肝疫苗注入前两组间吞噬细胞的吞噬功能无明显差异,疫苗注入后3个月和6个月时实组外周血吞噬细胞的吞噬功能明显下降(P〈0.05)。两组间同时间点相比,1个月和3个月都  相似文献   

13.
Two ternary complexes, [Cu2(Pir)(Pen)(OH)(Ac)H2O] and [Cu(Pir)(Cap)(Ac)] ½H2O (where, Pen = D-penicillamine, Cap = captopril, and Pir = piroxicam) have been synthesized and characterized using elemental analyses, spectroscopic analyses (IR, UV-vis, MS), thermal analyses (TGA), conductance measurements, and magnetic measurements. The binary complexes, [Cu2(Pen)(OH)2(H2O)2] 4H2O and [Cu(Cap)Ac] 3/2H2O, have also been prepared and characterized by these techniques to facilitate the interpretation of the mixed ligand complexes. The results show that D-penicillamine can coordinate two copper atoms through amino nitrogen, and thiol sulfur after displacement of a hydrogen atom. At the same time, the ligand coordinates to the second copper atom through a carboxyl group after displacement of a hydrogen from the latter group. Captopril coordinates through thiol sulfur and carbonyl oxygen. Piroxicam coordinates as a neutral bidentate ligand in the keto form through carbonyl oxygen and pyridyl nitrogen. The magnetic moment measurements of complexes containing captopril indicate the reduction of Cu(II) to Cu(I) by the thiol group.  相似文献   

14.
The present experiment was designed to study the 2.45 GHz low-level microwave (MW) irradiation-induced stress response and its effect on implantation or pregnancy in female mice. Twelve-week-old mice were exposed to MW radiation (continuous wave for 2 h/day for 45 days, frequency 2.45 GHz, power density?=?0.033549 mW/cm2, and specific absorption rate?=?0.023023 W/kg). At the end of a total of 45 days of exposure, mice were sacrificed, implantation sites were monitored, blood was processed to study stress parameters (hemoglobin, RBC and WBC count, and neutrophil/lymphocyte (N/L) ratio), the brain was processed for comet assay, and plasma was used for nitric oxide (NO), progesterone and estradiol estimation. Reactive oxygen species (ROS) and the activities of ROS-scavenging enzymes— superoxide dismutase, catalase, and glutathione peroxidase—were determined in the liver, kidney and ovary. We observed that implantation sites were affected significantly in MW-irradiated mice as compared to control. Further, in addition to a significant increase in ROS, hemoglobin (p?<?0.001), RBC and WBC counts (p?<?0.001), N/L ratio (p?<?0.01), DNA damage (p?<?0.001) in brain cells, and plasma estradiol concentration (p?<?0.05), a significant decrease was observed in NO level (p?<?0.05) and antioxidant enzyme activities of MW-exposed mice. Our findings led us to conclude that a low level of MW irradiation-induced oxidative stress not only suppresses implantation, but it may also lead to deformity of the embryo in case pregnancy continues. We also suggest that MW radiation-induced oxidative stress by increasing ROS production in the body may lead to DNA strand breakage in the brain cells and implantation failure/resorption or abnormal pregnancy in mice.  相似文献   

15.
Breynia distachia is a plant of genus Breynia belonging to family Phyllanthaceae. This study was conducted to isolate and examine the anti-inflammatory attributes of the roots of Breynia distachia. Methanol extract from roots were prepared by simple maceration. For phytochemical studies, isolation, purification, structure elucidation, metal analysis, total phenolic content, and solubility test were done by chromatographic and spectroscopic techniques. Anti-inflammatory activity was evaluated by cotton pallet edema model and carrageenan paw edema model, and antioxidant potential was evaluated by DPPH, FRAP, and ABTS antioxidants assays. Metal analysis of BD.Me revealed the presence of Na > Mg > K > Mn > Fe = Zn in respective order. Four phytochemicals such as gallic acid, quercetin, sinapic acid, and p-coumaric acid are found in Breynia distachia. Quercetin is present in relatively larger quantity, and shows antioxidant activity by reducing the ferric iron to ferrous iron. Novel distachionate shows high antioxidant activity in ABTS assay by reducing reactive oxygen species. Quantitative or qualitative analysis performed by HPLC indicates the ascending peaks or presence of secondary products (metabolites) respectively. Histopathology analysis of liver, spleen, heart, and kidney was done, revealing mild inflammations in spleen and liver, and no cytotoxicity in heart and kidney. Oral administration of BD.Me and ditachionate significantly inhibits the carrageenan and cotton pellet-induced paw edema in 1st and 2nd h with (ns = p > 0.05) than control. After 3rd, 4th, 5th, and 6th h, BD.Me and ditachionate showed inhibition of paw edema in a highly significant (*** = p < 0.001) manner as compared to control. In cotton-pellet edema model, distachionate shows a %inhibition of 57.3% at a dose level of 5 mg/kg. Docking values obtained from distachionate-COX-2 complex suggest a potent inhibitor evaluated for this protein. The distachionate shows effective anti-inflammatory activity. Methanol extracts of roots showed significant lipoxygenase inhibitory activity by IC50 values of 155.7 ± 0.55 and 132.9 ± 0.33 μg/mL. Data from various in vitro and in vivo models suggest that novel distachionate isolated from Breynia distachia shows strong antioxidant and anti-inflammatory activities; it should be further studied for the exploration of its medicinal potential.  相似文献   

16.
Present research was planned to assess the in vitro and in vivo anti-arthritic potential of Caralluma tuberculata N. E. Brown. methanolic (CTME) and aqueous (CTAQ) extracts. Chemical characterization was done by high-performance liquid chromatography and gas chromatography–mass spectrometry analysis. The Complete Freund’s Adjuvant (CFA) was injected in left hind paw of rat at day 1 and dosing at 150, 300 and 600 mg/kg was started on the 8th day via oral gavage in all groups except normal and disease control rats (which were given distilled water), whereas methotrexate (intraperitoneal; 1 mg/kg/mL) was administered to standard control. The CTME and CTAQ exerted significant (p < 0.01–0.0001) in vitro anti-arthritic action. Both extracts notably reduced paw edema, and restored weight loss, immune organs weight, arthritic score, RBCs, ESR, platelet count, rheumatoid factor (RF), C-reactive protein, and WBCs in treated rats. The plant extracts showed significant (p < 0.05–0.0001) downregulation of tumor necrosis factor-α, Interleukin-6, -1β, NF-κB, and cyclooxygenase-2, while notably upregulated IL-4, IL-10, I-κBα in contrast to disease control rats. The plant extracts noticeably (p < 0.001–0.0001) restored the superoxide dismutase and catalase activities and MDA levels in treated rats. Both extracts exhibited significant anti-arthritic potential. The promising potential was exhibited by both extracts probably due to phenolic, and flavonoids compounds.  相似文献   

17.
Plant-parasitic nematodes cause severe losses to crop production and economies all over the world. Bacillus aryabhattai MCCC 1K02966, a deep-sea bacterium, was obtained from the Southwest Indian Ocean and showed nematicidal and fumigant activities against Meloidogyne incognita in vitro. The nematicidal volatile organic compounds (VOCs) from the fermentation broth of B. aryabhattai MCCC 1K02966 were investigated further using solid-phase microextraction gas chromatography-mass spectrometry. Four VOCs, namely, pentane, 1-butanol, methyl thioacetate, and dimethyl disulfide, were identified in the fermentation broth. Among these VOCs, methyl thioacetate exhibited multiple nematicidal activities, including contact nematicidal, fumigant, and repellent activities against M. incognita. Methyl thioacetate showed a significant contact nematicidal activity with 87.90% mortality at 0.01 mg/mL by 72 h, fumigant activity in mortality 91.10% at 1 mg/mL by 48 h, and repellent activity at 0.01–10 mg/mL. In addition, methyl thioacetate exhibited 80–100% egg-hatching inhibition on the 7th day over the range of 0.5 mg/mL to 5 mg/mL. These results showed that methyl thioacetate from MCCC 1K02966 control M. incognita with multiple nematicidal modes and can be used as a potential biological control agent.  相似文献   

18.
Fungal polyketides have significant biological activities, yet the biosynthesis by highly reducing polyketide synthases (HRPKSs) remains enigmatic. An uncharacterized group of HRPKSs was found to contain a C‐terminal domain with significant homology to carnitine O ‐acyltransferase (cAT). Characterization of one such HRPKS (Tv6‐931) from Trichoderma virens showed that the cAT domain is capable of esterifying the polyketide product with polyalcohol nucleophiles. This process is readily reversible, as confirmed through the holo ACP‐dependent transesterification of the released product. The methyltransferase (MT) domain of Tv6‐931 can perform two consecutive α‐methylation steps on the last β‐keto intermediate to yield an α,α‐gem ‐dimethyl product, a new programing feature among HRPKSs. Recapturing of the released product by cAT domain is suggested to facilitate complete gem ‐dimethylation by the MT.  相似文献   

19.
Sun Y  Li HZ 《The Analyst》2000,125(12):2326-2329
A method for determination of selenium in plasma and hair with ternary inclusion compound-fluorescent spectrophotometry has been developed. The determination of selenium in plasma and hair can be performed directly in aqueous solution. Blood and hair samples were destroyed by oxygen flask combustion. The linear range was 10-500 ng mL-1 for plasma and 10-100 ng mL-1 for hair. Within-day and day-to-day precisions for plasma ranged from 5.4% to 9.3% (n = 7) and from 3.5% to 14.5% (n = 7), respectively. Within-day precisions for hair ranged from 0.6% to 6.2% (n = 7). Recoveries ranged from 91.0% to 97.8% for plasma and from 95.0% to 102.0% for hair. The blood samples from 15 Hans and 20 Uygurs in Xinjiang Uygur automatic region and 23 Hans in Liaoning province were collected and determined. It was indicated that no statistically significant difference in plasma selenium concentration of the Hans between Xinjiang and Liaoning was found (F = 1.36, P > 0.05). However, there were statistically significant differences between the Hans and the Uygurs in Xinjiang (F = 1.01, P < 0.01) and between males and females in the two areas (P < 0.01). There was a low correlation between plasma selenium concentration and hair selenium concentration. The ratio of hair selenium concentration to plasma selenium concentration was 2.17, with a range of 1.63-2.88.  相似文献   

20.
Endophytic fungal isolates Hypocrea lixii F3ST1 and Beauveria bassiana G1LU3 were evaluated for their potential to endophytically colonize and induce active compounds in Phaseolus vulgaris, as a defense mechanism against pea leafminer (Liriomyza huidobrensis) and fall armyworm (Spodoptera frugiperda). Endophytic colonization was achieved through seed inoculation with the volatile emissions from P. vulgaris plants being analyzed using GC-MS. The crude extracts of P. vulgaris obtained using methanol and dichloromethane were assayed against leafminer and fall armyworm larvae using leaf dipping and topical application, respectively. The two isolates successfully colonized the entire host plant (roots, stems, and leaves) with significant variation (p < 0.001) between fungal isolates and the controls. The results showed qualitative differences in the volatile profiles between the control plants, endophytically colonized and insect-damaged plants attributed to fungal inoculation and leafminer damage. The crude methanol extracts significantly reduced the percentage pupation of 2nd instar leafminer larvae (p < 0.001) and adult-flies emergence (p < 0.05). The survival of the 1st instar fall armyworm larvae was also significantly reduced (p < 0.001) compared to the controls. This study demonstrated the high potential of endophytic fungi H. lixii and B. bassiana in inducing mainly specific defense compounds in the common bean P. vulgaris that can be used against pea leafminer and fall armyworm.  相似文献   

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