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关键词： Lactase   Bacillus subtilis   ortho-nitrophenyl-beta-galactoside (ONPG)   X-gal   16S rDNA  

摘要： In the present study, the microbial source for potent lactase producers was explored to supplement the lactase intolerant individuals. Dairy effluent was screened for lactase producing bacteria by conventional microbiological methods. Among the positive isolates, one isolate VUVD001 was found to be a strong producer of lactase enzyme and this strain identified by 16S rDNA analysis. The lactase producing bacterium is identified as Bacillus subtilis by biochemical and 16S rDNA analysis. The VUVD001 strain found to survive in a temperature range of 20-55 degrees C, pH range of 5-8 and a salt concentration up to 8%. Further, the partially purified enzyme preparation was tested by zymogram analysis for activity testing using x-gal and the enzyme activity of cell free supernatant was estimated to be 15.10 U/ml at 37 degrees C, 4% NaCl and pH of 7.0. Our finding reports a new isolate Bacillus subtilis VUVD001 strain which can be used as potential strain for commercial production of lactase. (C) 2019 The Authors. Published by Elsevier B.V. on behalf of King Saud University.

关键词： Streptozotocin   Coenzyme Q10   Diabetes mellitus   Antioxidant   Glibenclamide  

摘要： Background Diabetes mellitus is a metabolic disorder caused by impaired glucose metabolism. Coenzyme Q10 is an endogenous vitamin with significant antioxidant properties. Aims and objective The aim of our study is to investigate the protective effect of coenzyme Q10 against streptozotocin-induced diabetic rats. Materials and methods Five groups of rats were used as follows: normal control (given normal saline), diabetic control (STZ 50 mg/kg b.w., i.p.), coenzyme Q10-treated diabetic rats (10 mg/kg b.w.), glibenclamide-treated diabetic rats (0.6 mg/kg b.w.) as standard group, and drug alone-treated group (coenzyme Q10 10 mg/kg b.w.). The rats were sacrificed after the study duration of 30 days. Biochemical and antioxidant parameters and histopathological evaluation were carried out in experimental rats. Results and discussion The diabetic control group showed significant alterations in biochemical and histological parameters. Coenzyme Q10 was able to bring back the altered parameters to normal levels which were similar to that of the glibenclamide-treated group. Conclusion Coenzyme Q10 could, therefore, be used as an adjunct in the management of diabetes. Antidiabetic activity of conenzyme Q10

关键词： Methanococcoides methylutens   Monomeric isocitrate dehydrogenase   Lateral gene transfer   Biochemical characterization   Coenzyme specificity  

摘要： Monomeric isocitrate dehydrogenase (IDH) stands for a separated subgroup among IDH protein family. Up to now, all reported monomeric IDHs are from prokaryotes. Here, a monomeric IDH from a marine methanogenic archaeon Methanococcoides methylutens (MmIDH) was reported for the first time. BLAST search demonstrated that only a few marine archaea encode the monomeric IDH and all these organisms are methylotrophic. MmIDH shows the highest homology (similar to 70%) to the monomeric IDHs from some marine bacteria, suggesting a lateral gene transfer event between marine bacteria and archaea. The monomeric state of MmIDH was determined by size exclusion chromatography. MmIDH is divalent cation-dependent and Mn2+ is the most favored. Kinetic analysis showed that MmIDH is highly specific to NADP(+) and cannot utilize the NAD(+). The optimal temperature for MmIDH activity is 50 degrees C and the optimal pH is 8.2. Heat inactivation assay revealed that MmIDH is a mesophilic enzyme. It sustained 50% activity after incubation at 39 degrees C for 20 min. Moreover, the putative coenzyme binding residues (His590, Arg601, and Arg650) of MmIDH were explored by mutagenesis. The triple mutant H590L/R601D/R650S displayed a 5.93-fold preference for NAD(+) over NADP(+), indicating that the coenzyme specificity of MmIDH was significantly switched from NADP(+) to NAD(+) by three key mutations.

关键词： creatine phosphokinase   neuromuscular fatigue   tensiomyography   exercise  

摘要： Gutierrez-Vargas, R, Martin-Rodriguez, S, Sanchez-Urena, B, Rodriguez-Montero, A, Salas-Cabrera, J, Gutierrez-Vargas, JC, Simunic, B, and Rojas-Valverde, D. Biochemical and muscle mechanical postmarathon changes in hot and humid conditions. J Strength Cond Res 34(3): 847-856, 2020-The aim of this study was to compare biochemical changes and mechanical changes in the lower-limb muscles before and after a marathon race in hot and humid conditions. Eighteen healthy runners participated in a marathon at between 28 and 34 degrees C and 81% humidity in Costa Rica. Serum magnesium (Mg2+), creatine phosphokinase (CPK), lactate dehydrogenase, and hematocrit (HCT) were measured before and after the marathon. Tensiomyography measurements from the rectus femoris (RF) and vastus medialis, muscle displacement (Dm), contraction time (Tc), and velocities of contraction to 10 and 90% of Dm (V-10 and V-90) were obtained before and after the marathon. Postrace measurements showed a 544% increase in CPK (t(17): -6.925, p < 0.01), a 16% increase in HCT (t(17): -7.466, p < 0.01), a 29% decrease in Mg2+ (t(17): 3.91, p = 0.001), a 2% decrease in body mass (t(17): 4.162, p = 0.001), a 4% increase in Tc of the RF (t(17): -2.588, p = 0.019), and a 12% increase in Dm of the RF (t(17): -2.131, p < 0.048) compared with prerace measurements. No significant biochemical or mechanical differences were found between runners in terms of their finish times. These findings showed that completing a marathon in hot and humid conditions induced a significant reduction in lower-limb muscle stiffness, body mass, and Mg2+, and increased neuromuscular fatigue, CPK, and HCT, because of muscle damage and dehydration. Knowledge of the effects of heat and humidity may be of value for coaches and sports medicine practitioners in developing effective hydration and recovery protocols for marathon runners in these special conditions.

关键词： Senecio scandens buch-ham extracts   Hybrid grouper   Plasma biochemical   Histology   Immune-related genes  

摘要： The study mainly aimed at the effects of dietary Senecio scandens buch-harn extract (SSBE) on the growth performance, body composition, plasma biochemical index, intestinal and liver histology and the expression of antioxidant, apoptosis and inflammatory related genes in hybrid grouper (Epinephelus lanceolatus male x Epinephelus fuscoguttatus female). Basal diets supplemented with SSBE (10:1) 0%, 0.05%, 0.1%, 0.2% and 0.4% were fed hybrid grouper for 8 weeks. The results showed that WGR and SGR were significantly increased in the week 2 and week 4 in Diet 0.05% group (P < 0.05). The total protein, globulin and albumin significantly increased whereas alanine aminotransferase, triglyceride and alkaline phosphate in the plasma were significantly decreased in Diet 0.1% group (P < 0.05). The villi length, width, muscle thickness and the cross-sectional area of intestine were improved in Diet 0.05% and Diet 0.1% group. The expression levels of PPAR-alpha and CPT-1 in the liver of hybrid grouper were significantly increased following the supplementation of SSBE (P < 0.05). The expression levels of antioxidant related genes (CAT, GPX, GR and Keap1) and anti-inflammatory factor (IL-10) in liver, head kidney and spleen of hybrid grouper decreased significantly (P < 0.05). In addition, diets supplemented with 0.05%-0.1% SSBE had a good liver-protecting effect, but it would have a detrimental effect on hepatocytes when the content exceeds 0.2%. The above results indicated that the suitable additive amount of SSBE in hybrid grouper feed was 0.05%-0.1%.

关键词： Lamiaceae   essential oils   extracts   phytocomplexes   phytochemistry   biological activity  

摘要： Lamiaceae is one of the largest families of flowering plants comprising about 250 genera and over 7,000 species. Most of the plants of this family are aromatic and therefore important source of essential oils. Lamiaceae are widely used as culinary herbs and reported as medicinal plants in several folk traditions. In the Mediterranean area oregano, sage, rosemary, thyme and lavender stand out for geographical diffusion and variety of uses. The aim of this review is to provide recent data dealing with the phytochemical and pharmacological studies, and the more recent applications of the essential oils and the non-volatile phytocomplexes. This literature survey suggests how the deeper understanding of biomolecular processes in the health and food sectors as per as pest control bioremediation of cultural heritage, or interaction with human microbiome, fields, leads to the rediscovery and new potential applications of well-known plants.

关键词： Intracellular signaling   Reelin   Tauopathy   Electrophysiology   Cognition   Alzheimer's disease  

摘要： Reelin is an extracellular protein crucial for adult brain plasticity. Moreover, Reelin is protective against amyloid-beta (A beta) pathology in Alzheimer's Disease (AD), reducing plaque deposition, synaptic loss and cognitive decline. Given that Tau protein plays a key role in AD pathogenesis, and that the Reelin pathway modulates Tau phosphorylation, here we explored the involvement of Reelin in AD-related Tau pathology. We found that Reelin overexpression modulates the levels of Tau phosphorylation in AD-related epitopes in VLW mice expressing human mutant Tau. in vitro, Reelin reduced the A beta-induced missorting of axonal Tau and neurofilament proteins to dendrites. Reelin also reverted in vivo the toxic somatodendritic localization of phosphorylated Tau. Finally, overexpression of Reelin in VLW mice improved long-term potentiation and long-term memory cognitive performance thus masking the cognitive and physiological deficits in VLW mice. These data suggest that the Reelin pathway, which is also protective against A beta pathology, modulates fundamental traits of Tau pathology, strengthening the potential of Reelin as a therapeutic target in AD.

关键词： Actin   Microfluidics   Microscopy   Cofilin   Formin  

摘要： The regulated assembly of actin filaments is essential in nearly all cell types. Studying actin assembly dynamics can pose many technical challenges. A number of these challenges can be overcome by using microfluidics to observe and manipulate single actin filaments under an optical microscope. In particular, microfluidics can be tremendously useful for applying different mechanical stresses to actin filaments and determining how the physical context of the filaments affects their regulation by biochemical factors. In this review, we summarize the main features of microfluidics for the study of actin assembly dynamics, and we highlight some recent developments that have emerged from the combination of microfluidics and other techniques. We use two case studies to illustrate our points: the rapid assembly of actin filaments by formins and the disassembly of filaments by actin depolymerizing factor (ADF)/cofilin. Both of these protein families play important roles in cells. They regulate actin assembly through complex molecular mechanisms that are sensitive to the filaments' mechanical context, with multiple activities that need to be quantified separately. Microfluidics-based experiments have been extremely useful for gaining insight into the regulatory actions of these two protein families.

关键词： Antioxidant properties   Biochemical contents   Compost   Moringa oleifera   NPK fertilizer   Plant nutrition  

摘要： Organic and inorganic fertilizers play a significant role in improving the nutritional quality of Moringa plant (Moringa oleifera). A field experiment of six treatments (control;5 t/ha Compost;120 kg/ha NPK;50 + 50%/ha (NPK + Compost);10 + 50%/ha (NPK + Compost);and 50 + 10%/ha (NPK + Compost) with three replications was conducted in a randomized complete block design in order to evaluate the effect of the application of compost and NPK fertilizer in various combinations on the biochemical and antioxidant potential of the Moringa plant. The results showed a significant influence of the compost and NPK fertilizer in various combination on the biochemical and antioxidant properties of the plant. Higher amount of carbohydrate, phenolic and flavonoid contents (406.24, 45.23 and 1.69 mg g(-1) dry wt., respectively) were observed in the plant treated with 50 + 50%/ha (NPK + Compost). Protein content (27.91 mg g(-1) dry wt.) was improved by the application of 120 kg/ha NPK fertilizer. The antioxidant properties such as, DPPH, ABTS and nitric oxide were analyzed as percentage scavenging and half maximal effective concentration (EC50) whereas ferric-reducing antioxidant potential (FRAP) was determined in terms of absorbance at 700 nm and EC0.50. The half maximal effective concentrations in combined application of NPK and compost (50 + 50%/ha (NPK + Compost)) were the lowest among the fertilizer treatments, resulting in EC50 value of 27.61, 17.18, 104.24 mu g mL(-1) for DPPH, ABTS and nitric oxide assays, respectively whereas in case of the FRAP assay the EC0.50 value as found out to be 292.35 mu g mL(-1). (C) 2019 SAAB. Published by Elsevier B.V. All rights reserved.

关键词： Trifalium pratense   Cold acclimation   Recurrent selection   LT50   Carbohydrates   Differentially-expressed genes   Amino acids  

摘要： Low freezing tolerance reduces the persistence of red clover under northern climate. The incidence of winter damages in perennial crops could increase in the future due to the adverse effects of the predicted warmer fall temperature on plant cold acclimation. To accelerate breeding progress, two cultivars of red clover Christie (C-TF0) and Endure (E-TF0) were exposed to a recurrent selection protocol for freezing tolerance performed indoor. New populations were obtained after five (C-TF5 and E-TF5), six (C-TF6 and E-TF6), and seven (C-TF7 and E-TF7) cycles of recurrent selection. These populations were overwintered under natural conditions and monitored for freezing tolerance and cold-induced molecular traits. Freezing tolerance was improved by up to 6 degrees C in recurrently selected populations when compared to initial cultivars confirming that further progress are achieved with advanced cycles of selection. Monthly analysis of biochemical changes shows that higher starch concentrations at the onset of the fall hardening period are contributing to the acquisition of superior freezing tolerance through its impact on sucrose accumulation. They also contribute to the vigor of spring regrowth by sustaining more pinitol and proline synthesis. Larger concentrations of these metabolites in populations with higher levels of freezing tolerance (TF7) hint at their involvement in winter survival of red clover. Among genes differentially expressed in response to both cold acclimation and recurrent selection, a concomitant cold induction of APPR9 and cold repression of 1-aminocyclopropane-carboxylate synthase suggests a link between the repression of a pathway regulated by ethylene and the improvement of freezing tolerance in red clover.