摘要 :
Various raw materials are used to produce vinegars that contain functional compounds associated with disease prevention. We evaluated changes in functional compounds during tomato vinegar production and superoxide dismutase-like a...
展开
Various raw materials are used to produce vinegars that contain functional compounds associated with disease prevention. We evaluated changes in functional compounds during tomato vinegar production and superoxide dismutase-like activity of tomato vinegar. Tomato vinegar contained abundant anti-hypertensive compounds, e.g., -aminobutyric acid and potassium derived from tomatoes and acetic acid and pyroglutamic acid produced during fermentation. It had stronger superoxide dismutase-like activity than commercial vinegars because of tomato-derived superoxide dismutase-like compounds, including phenolic acids, flavonoids, and glutathione. These data indicate that tomato vinegar is a candidate dietary supplement with potential preventive effects against cardiovascular diseases due to its anti-hypertensive and superoxide dismutase-like compounds.
收起
摘要 :
Due to possessing an extremely small size and a large surface area per unit of volume, nanomaterials have specific characteristic physical, chemical, photochemical, and biological properties that are very useful in many new applic...
展开
Due to possessing an extremely small size and a large surface area per unit of volume, nanomaterials have specific characteristic physical, chemical, photochemical, and biological properties that are very useful in many new applications. Nanoparticles' catalytic activity and intrinsic ability in generating or scavenging reactive oxygen species in general can be used to mimic the catalytic activity of natural enzymes. Many nanoparticles with enzyme-like activities have been found, potentially capable of being applied for commercial uses, such as in biosensors, pharmaceutical processes, and the food industry. To date, a variety of nanoparticles, especially those formed from noble metals, have been determined to possess oxidase-like, peroxidase-like, catalase-like, and/or superoxide dismutase-like activity. The ability of nanoparticles to mimic enzymatic activity, especially peroxidase mimics, can be used in a variety of applications, such as detection of glucose in biological samples and waste water treatment. To study the enzyme-like activity of nanoparticles, the electron spin resonance method represents a critically important and convenient analytical approach for zero-time detection of the reactive substrates and products as well as for mechanism determination.
收起
摘要 :
Copper complexes with transformed methimazole ligand have been synthesized and characterized by elemental analysis, conductivity measurements, thermogravimetric analysis, EPR, FTIR and UV-Vis spectroscopies. Results support their ...
展开
Copper complexes with transformed methimazole ligand have been synthesized and characterized by elemental analysis, conductivity measurements, thermogravimetric analysis, EPR, FTIR and UV-Vis spectroscopies. Results support their stoichiometries and geometrical structures: [Cu(C4H5N2S)(2)Cl-2]center dot 2H(2)O(1), [Cu(C8H10N4S)SO4H2O](2) and [Cu(C8H10N4S)SO4](3). ((C4H5N2)(2)S: bis(l-methylimidazol-2-yl)sulfide; (C4H5N2S)(2) = Bis[bis(l-methylimidazol-2-yl)disulfide]) Concurrently, the structurally distinct soluble species corresponding to complexes (1) and (2) were subsequently used in an in vitro investigation of their potential biological properties. In view of their possible pharmaceutical activity, the complexes were in vitro evaluated as phosphatase acid inhibitors. Their radical bio-protective effects were also studied measuring the effect against DPPH center dot and O-2(center dot-) radicals. Additional catalytic properties as peroxidase mimics were evaluated using Michaelis-Menten kinetic model by means of phenol red and pyrogallol assays. The complexes exhibited catalytic bromination activity and the ability to oxidize pyrogallol substrate indicating that they can be considered as functional models. The relationships between the structures and the in vitro biological activities have also been considered. Serum protein albumin has attracted the greatest interest as drug carrier and the affinity of biological/pharmaceutical compound is relevant to the development of new medicine. In that sense, interaction studies by fluorescence and EPR spectroscopies were performed showing the binding capacity of the complexes.
收起
摘要 :
Analyzing the SOD-like activity of nanozymes in vitro is of great importance for identifying new nanozymes and predicting their potential biological effects in vivo. However, false negative or positive results occasionally occur d...
展开
Analyzing the SOD-like activity of nanozymes in vitro is of great importance for identifying new nanozymes and predicting their potential biological effects in vivo. However, false negative or positive results occasionally occur due to the mismatch between the detection methods and nanozymes. Here, five typical SOD-like nanozymes, including CeO_2, Mn_3O_4, Prussian blue (PB), PCN222-Mn, and Pt NPs, have been used to evaluate the sensitivity and accuracy of several commonly used in vitro detection methods. By systematically analyzing the detection results, several precautions have been taken. (1) The hydroethidine (HE) probe could be disturbed by the nanozyme with oxidative ability. (2) The nitro blue tetrazolium (NBT) probe has a moderate sensitivity due to the poor water solubility of its reduced product. (3) The water-soluble tetrazolium salt (WST)-8 probe has a higher sensitivity than both NBT and iodonitrotetrazolium chloride (INT). (4) The detection system using the irradiation of riboflavin to produce ?O_2~? might be interfered by the nanozyme with photosensibility. (5) Both the quality of DMPO and incubation time are important factors for electron paramagnetic resonance (EPR) measurement. This study will be useful for choosing more suitable in vitro detection methods of SOD-like activity for nanozymes in the future.
收起
摘要 :
Seeds of double low oilseed rape variety Mango (Brassica napus, var. oleifera) were subjected to a 7-day germination at 25℃ and 95% moisture content in darkness in a conditioning cabinet. The effects of the germination process on...
展开
Seeds of double low oilseed rape variety Mango (Brassica napus, var. oleifera) were subjected to a 7-day germination at 25℃ and 95% moisture content in darkness in a conditioning cabinet. The effects of the germination process on the superoxide dismutase-like activity (SOD-like activity), thiamine (vitamin B_1) and riboflavin (vitamin B_2) and minerals, such as Ca, Mg, Cu, Fe and Mn, were studied. Correlations between individual mineral contents, vitamin B_1 and B_2 contents, and the ability of phosphate buffered saline (PBS) extracts from germinated rapeseed to scavenge superoxide anion radicals in vitro were also investigated. SOD-like activity showed a gradual increase after the second day of germination, reaching a maximum level on the sixth day, and remained almost constant up to the end of the germination period. During germination, thiamine underwent a progressive decrease up to the sixth day, reaching a constant level between the sixth and the seventh day. In contrast, riboflavin content increased throughout the germination period up to the fifth day, and after that a constant level was observed. Levels of Ca and Mg were almost constant up to the fourth day and after that an increase of these minerals was observed. Cu and Mn increased during the germination process, and retentions of 33% and 22%, respectively, were observed at the end of germination. Fe content dropped after 1 day of germination and from there onward it started to increase gradually and an 18% retention was observed in 7-day germinated seeds. Positive correlations between SOD-like activity and riboflavin (r = 0.87), Cu (r = 0.74) and Mn (r = 0.87) were found during rapeseed germination.
收起
摘要 :
The purpose of this experiment was to evaluate the superoxide dismutase (SOD)-like activity of boar seminal plasma, the change of SOD-like activity in the semen stored in Modena extender during preservation and to clarify the effe...
展开
The purpose of this experiment was to evaluate the superoxide dismutase (SOD)-like activity of boar seminal plasma, the change of SOD-like activity in the semen stored in Modena extender during preservation and to clarify the effect of addition of SOD to Modena extender on the motility of boar spermatozoa. The SOD-like activity was measured by Electron Spin Resonance Spectroscopy. The SOD-like activities of semina plasma of boar A and B were 9.7+-0.9#mu#/ml and 6.1+-0.2#mu#/ml, respectively. The SOD-like activity in the semen diluted with Modena extender did not change during the storage peiod of 28 days at 10 deg C. The addition of SOD to the extended semen improved sperm viability during storage of 28 days and the best result was obtained from the spermatozoa suspended in Modena extender added 800#mu#/ml of SOD. The results suggest that the addition of SOD to Modena extender is useful for long-term maintenance of good motility in liquid storage of boar spermatozoa.
收起
摘要 :
Chronic wounds caused by bacterial infections are a major challenge in
medical fields. The hypoxia condition extremely induces reactive oxygen
species (ROS) generation and upregulates the expression of hypoxia-inducible
factor,...
展开
Chronic wounds caused by bacterial infections are a major challenge in
medical fields. The hypoxia condition extremely induces reactive oxygen
species (ROS) generation and upregulates the expression of hypoxia-inducible
factor, both of which can increase the pro-inflammatory M1 subtype
macrophages production while reducing the anti-inflammatory M2 subtype
macrophages. Besides, bacteria-formed biofilms can hinder the penetration of
therapeutic agents. Encouraged by natural motors automatically executing
tasks, hypothesized that supplying sufficient oxygen (O_2) would
simultaneously drive therapeutic agent movement, rescue the hypoxic
microenvironment, and disrupt the vicious cycle of inflammation. Here, small
organic molecule-based nanoparticles (2TT-mC6B@Cu_(5.4)O NPs) that possess
high photothermal conversion efficiency and enzymatic activities are
developed, including superoxide dismutase-, catalase-, and glutathione
peroxidase-like activity. 2TT-mC6B@Cu_(5.4)O NPs exhibit superior
ROS-scavenging and O_2 production abilities that synergistically relieve
inflammation, alleviate hypoxia conditions, and promote their deep
penetration in chronic wound tissues. Transcriptome analysis further
demonstrates that 2TT-mC6B@Cu5.4O NPs inhibit biological activities inside
bacteria. Furthermore, in vivo experiments prove that 2TT-mC6B@Cu_(5.4)O
NPs-based hyperthermia can effectively eliminate bacteria in biofilms to
promote wound healing.
收起
摘要 :
AuNPs with enzyme-like features have received strong attention in different areas, although limited data is available in literature on their biological/industrial functions. NPs especially Au counterparts have been shown to functi...
展开
AuNPs with enzyme-like features have received strong attention in different areas, although limited data is available in literature on their biological/industrial functions. NPs especially Au counterparts have been shown to functionally mimic the activity of antioxidant enzyme. Indeed, due to low cytotoxicity and SPR characteristics of AuNPs, there are a great number of reports in which Au nanozymes yield promising responses in biomedical applications. In this review, we aim to overview the enzymatic activity of Au nanozymes along with their regulatory and controlling mechanisms. We have reviewed the effect of various factors such as dimension, morphology, functionalization and presence of hybrid materials on the catalytic activity of Au nanozymes as well as a detail survey on the oxidase, peroxidase, SOD, and CAT-like activities of Au nanozyme. Finally, the significance of Au nanozymes in mitigating oxidative stress followed by conclusion and challenges were reported. Based on this paper, we envision that Au nanozymes can be used as a promising material to prevent oxidative stress-stimulated disorders. (C) 2019 Elsevier B.V. All rights reserved.
收起
摘要 :The systematical investigations on the catalytic mechanisms of dismutation reactions for the superoxide dismutase (SOD) mimics of Cu(bpy)Br2 and its derivatives Cu(L1)Br2 and Cu(L2)Br2 (bpy=2,2’- dipyridyl, L1=5,5’- di[1- (triet...
展开
The systematical investigations on the catalytic mechanisms of dismutation reactions for the superoxide dismutase (SOD) mimics of Cu(bpy)Br2 and its derivatives Cu(L1)Br2 and Cu(L2)Br2 (bpy=2,2’- dipyridyl, L1=5,5’- di[1- (triethylammonio)methyl]- 2,2’- dipyridyl cation and L2=5,5’- di [1- (tributylammonio)methyl]- 2,2’- dipyridyl cation) have been carried out by the DFT/UB3LYP method. The catalytic reaction for each of these compounds is confirmed to be a redox cycle consisting of two half-reactions. In the first half-reaction, a proton is transferred from hydroperoxide neutral radical (·OOH) to one nitrogen atom of pyridinic ring with Cu(II) being reduced to Cu(I) in the meantime. In the second half-reaction, the proton is transferred back to another hydroperoxide radical (·OOH) to form hydrogen peroxide molecule, oxidizing Cu(I) back to its initial state. Our results show that the first half-reaction for all reactions is the rate-controlling step with the forward barrier values of 6.61, 4.84, 3.79 kcal·mol?1 for Cu(bpy)Br2, Cu(L1)Br2, and Cu(L2)Br2, respectively. Consequently, the SOD-like activities of the three mimics are in the order of Cu(bpy)Br2 < Cu(L1)Br2 < Cu(L2)Br2. The effect factors on the SOD-like activity for the studied compounds have also been discussed.
收起
原文获取