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211.

Angiotensin converting enzyme (ACE) is considered as main causative agent in growing hypertension and other cardiovascular disorders. Inhibition of ACE by producing and purifying bioactive peptides of fermented goat milk is aimed in this study. Protein extracted from goat milk was hydrolyzed with proteolytic enzymes of LH (Lactobacillus helveticus-cicc22171). ACE inhibitory peptides were purified from fermented samples of goat milk protein by optimizing incubation time to 8 h (S-8), 16 h (S-16), 24 h (S-24) and 36 h (S-36), via ultrafiltration. S-8 was used as control to compare the ACE inhibition trend. Molecular weight cut-off; 10000 Da (PM-10) and Ultracel 3K membrane was used to perform ultrafiltration. Sample with 24 h incubation time was considered as best hydrolyzed as compared to others, by applying Nin-Hydrin reaction and SDS-PAGE analysis. ACE inhibitory assay validated the authenticity of S-24 in inhibiting ACE, in vitro. Furthermore, Q executive hybrid quadrupole-orbitrap mass spectrometry was used to determine molecular structure and amino acid sequence of ACE inhibitory peptides. Three peptides, VLPVPQKAVPQ, VLPVPQKVVPQ and TQTPVVVPPFLQPEIMGVPKVKE containing functional amino acid structure, has been identified with highest ACE inhibitory activity on the basis of intensity, size and higher concentration of hydrophobic amino acids as shown in figure as graphical abstract. Fermented goat milk containing these novel bioactive peptides, can be used as nutraceuticals to inhibit ACE and control hypertension in future.

Graphical Abstract
  相似文献   
212.
Sturgeon (Chondrostei, Acipenseriformes) are threatened or endangered species due to overfishing and environmental degradation causing disruption of natural reproduction. Commercial sturgeon aquaculture and conservation program requires broodfish management as well as biogeographical and biological knowledge. Therefore, control of sturgeon reproduction in captivity can become as a valid tool in the field of sustainable development. The main objectives of the present review were to summarize, describe and synthesize available data about neuroendocrine control of testicular development, spermiation induction, seminal plasma characteristics and factors affecting sperm quality. In sturgeon, puberty usually occurs late in life and adult males do not spawn on an annual basis. Gonadal differentiation and spermatogonia proliferation occurs at 1?C2 and 2?C3?year-old, respectively. In spermatogenesis, environmental stimuli affect hypothalamus to release GnRH, which induce FSH release from pituitary stimulating testicular androgenesis, which is involved in spermatogonial proliferation and spermatogenesis. At spawning season, GnRH stimulates LH production from pituitary, regulating 17??,20??-dihydroxy-4-pregnen-3-one production in testis, which control sperm maturation. In captivity, hormonal treatment is essential to induce spermiation. Chemical and biochemical compounds of the seminal plasma are important to protect viability, motility and fertilizing capacity of spermatozoa. Several kinds of acrosomal enzymes have been identified in sturgeon seminal plasma; higher concentrations reported in the frozen/thawed than fresh sperm suggesting their origination from spermatozoa. Moreover, there are numerous factors that influence on sperm quality including temperature, methods for spermiation induction, stripping frequency and stress.  相似文献   
213.
Structural heat treatment, a viable alternative to methyl bromide fumigation, involves raising the ambient temperature of food-processing facilities between 50 and 60 degrees C by using gas, electric, or steam heaters, and holding these elevated temperatures for 24 h or longer to kill stored-product insects. A dynamic model was developed to predict survival of mature larvae, which is the most heat-tolerant stage of the confused flour beetle, Tribolium confusum (Jacquelin du Val), at elevated temperatures between 46 and 60 degrees C. The model is based on two nonlinear relationships: 1) logarithmic survival of T. confusum mature larvae as a function of time, and 2) logarithmic reduction in larval survival as a function of temperature. The dynamic model was validated with nine independent data sets collected during actual facility heat treatments conducted on two separate occasions at the Kansas State University pilot flour and feed mills. The rate of increase of temperature over time varied among the nine locations where mature larvae of T. confusum were exposed, and the approximate heating rates during the entire heat treatment ranged from 1.1 to 13.2 degrees C/h. The absolute deviation in the predicted number of larvae surviving the heat treatment was within 3-7% of the actual observed data. Comparison of the absolute deviation in the time taken for equivalent larval survival showed that the model predictions were within 2-6% of the observed data. The dynamic model can be used to predict survival of mature larvae of T. confusum during heat treatments of food-processing facilities based on time-dependent temperature profiles obtained at any given location.  相似文献   
214.
Floral induction by night interruption of Fuchsia hybrida cv. Lord Byron, a quantitative long-day plant with decussate phyllotaxis and an indeterminate flowering habit, altered neither the rate of leaf initiation nor the rate of leaf expansion; nor did flower initiation and development change the vegetative growth of the plants. This was diagnosed using plastochron duration and plastochron ratio measurements before, during, and after a 10-day induction period. A comparison between indeterminate and determinate flowering is made using these two parameters.  相似文献   
215.
The 1,044 bp endo-1,4-β-xylanase gene of a hyperthermophilic Eubacterium, "Thermotoga petrophila RKU 1" (T. petrophila) was amplified, from the genomic DNA of donor bacterium, cloned and expressed in mesophilic host E. coli strain BL21 Codon plus. The extracellular target protein was purified by heat treatment followed by anion and cation exchange column chromatography. The purified enzyme appeared as a single band, corresponding to molecular mass of 40 kDa, upon SDS-PAGE. The pH and temperature profile showed that enzyme was maximally active at 6.0 and 95 °C, respectively against birchwood xylan as a substrate (2,600 U/mg). The enzyme also exhibited marked activity towards beech wood xylan (1,655 U/mg). However minor activity against CMC (61 U/mg) and β-Glucan barley (21 U/mg) was observed. No activity against Avicel, Starch, Laminarin and Whatman filter paper 42 was observed. The K(m), V(max) and K (cat) of the recombinant enzyme were found to be 3.5 mg ml(-1), 2778 μmol mg(-1)min(-1) and 2,137,346.15 s(-1), respectively against birchwood xylan as a substrate. The recombinant enzyme was found very stable and exhibited half life (t(?)) of 54.5 min even at temperature as high as 96 °C, with enthalpy of denaturation (ΔH*(D)), free energy of denaturation (ΔG*(D)) and entropy of denaturation (ΔS*(D)) of 513.23 kJ mol(-1), 104.42 kJ mol(-1) and 1.10 kJ mol(-1)K(-1), respectively at 96 °C. Further the enthalpy (ΔH*), Gibbs free energy (ΔG*) and entropy (ΔS*) for birchwood xylan hydrolysis by recombinant endo-1,4-β-xylanase were calculated at 95 °C as 62.45 kJ mol(-1), 46.18 kJ mol(-1) and 44.2 J mol(-1) K(-1), respectively.  相似文献   
216.
Limited soil water availability is a major threat to agricultural productivity because it inhibits plant growth and yields. Various strategies have been adopted to mitigate water deficit stress in plants; however, using extremophilic microbes with plant growth promoting traits could be an environmentally friendly and cost-effective approach to improve crop stress resilience. Rhizobia are well known for their symbiotic association with legumes, but they can also improve the fitness of non-legumes under stressed conditions. Thus, different rhizobial strains were isolated from nodules of two legumes (lentil and chickpea) and tested for osmoadaptation at four different polyethylene glycol (PEG-6000) levels, i.e., ? 0.05, ? 0.65, ? 1.57, and ? 2.17 MPa. Two stress-tolerant rhizobial strains, SRL5 and SRC8, were selected to evaluate their potential to induce tolerance against water deficits in wheat grown at four different percentages of field capacity (FC; 40, 60, 80, and 100%). Rhizobial inoculation improved physiological parameters and growth of wheat under water deficit; however, co-inoculation of selected rhizobia was better than sole application. Grain yield was most limited at the highest level of water deficit but sole inoculation with SRC8 and SRL5 improved yield by 24% and 19%, respectively. Combined inoculation increased grain yield by up to 48% compared to the uninoculated control. Thus, rhizobia from different legumes possess enormous potential for improving the resilience of cereals (non-legumes) to water deficit stress. Moreover, co-inoculation of rhizobia could be more beneficial than their sole application.  相似文献   
217.
The Drosophila Dachsous and Fat proteins function as ligand and receptor, respectively, for an intercellular signaling pathway that regulates Hippo signaling and planar cell polarity. Although gene-targeted mutations in two mammalian Fat genes have been described, whether mammals have a Fat signaling pathway equivalent to that in Drosophila, and what its biological functions might be, have remained unclear. Here, we describe a gene-targeted mutation in a murine Dachsous homolog, Dchs1. Analysis of the phenotypes of Dchs1 mutant mice and comparisons with Fat4 mutant mice identify requirements for these genes in multiple organs, including the ear, kidney, skeleton, intestine, heart and lung. Dchs1 and Fat4 single mutants and Dchs1 Fat4 double mutants have similar phenotypes throughout the body. In some cases, these phenotypes suggest that Dchs1-Fat4 signaling influences planar cell polarity. In addition to the appearance of cysts in newborn kidneys, we also identify and characterize a requirement for Dchs1 and Fat4 in growth, branching and cell survival during early kidney development. Dchs1 and Fat4 are predominantly expressed in mesenchymal cells in multiple organs, and mutation of either gene increases protein staining for the other. Our analysis implies that Dchs1 and Fat4 function as a ligand-receptor pair during murine development, and identifies novel requirements for Dchs1-Fat4 signaling in multiple organs.  相似文献   
218.
219.
There is a need for recent information on intermediate snail hosts of schistosomes in The Gambia; the previous studies were conducted over three decades ago. This study assessed the incidence, species diversity, distribution and infection status of schistosome intermediate snail hosts in the country. Malacological surveys were conducted in all 5 regions of The Gambia: Central River Region (CRR), Upper River Region (URR), Western Region (WR), Lower River Region (LRR) and North Bank Region (NBR). Sampling of snails was undertaken at 114 sites that included permanent water bodies such as streams (bolongs), rice fields, irrigation canals and swamps; and temporal (seasonal) laterite pools. Ecological and physicochemical factors of sites were recorded. Snails were identified morphologically and screened for schistosome infections using molecular techniques. Freshwater snails were found at more than 50% (60/114) of sites sampled. While three species of Bulinus were collected, no Biomphalaria snails were found in any of the sites sampled. Of the total 2877 Bulinus snails collected, 75.9% were identified as Bulinus senegalensis, 20.9% as Bulinus forskalii and 3.2% as Bulinus truncatus. Seasonal pools produced the largest number of snails, and CRR was the region with the largest number of snails. Bulinus senegalensis was found more in seasonal pools as opposed to permanent sites, where B. forskalii and B. truncatus were observed to thrive. Bulinus snails were more common in seasonal sites where aquatic vegetation was present. In permanent sites, the abundance of snails increased with increase in water temperature and decrease in water pH. Bulinus senegalensis was found infected with both S. haematobium and S. bovis, while B. forskalii and B. truncatus had only S. bovis infection. While the human parasite S. haematobium was restricted to just four sites, the livestock parasite S. bovis had a much more widespread geographical distribution across both CRR and URR. This new information on the distribution of intermediate snail hosts of schistosomes in The Gambia will be vital for the national schistosomiasis control initiative.  相似文献   
220.
Central Asian Strain 1 (CAS1) is the prevalent Mycobacterium tuberculosis genogroup in South Asia. CAS1 strains carry deletions in RD149 and RD152 regions. Significance of these deletions is as yet unknown. We compared CAS1 strains with RD149 and concurrent RD149-RD152 deletions with CAS1 strains without deletions and with the laboratory reference strain, M. tuberculosis H37Rv for growth and for induction of TNFα, IL6, CCL2 and IL10 in THP-1 cells. Growth of CAS1 strains with deletions was slower in broth (RD149; p?=?0.024 and RD149-RD152; p?=?0.025) than that of strains without deletions. CAS1 strains with RD149 deletion strains further showed reduced intracellular growth (p?=?0.013) in THP-1 cells as compared with strains without deletions, and also as compared with H37Rv (p?=?0.007) and with CAS1 RD149-RD152 deletion strains (p?=?0.029). All CAS1 strains induced higher levels of TNFα and IL10 secretion in THP-1 cells than H37Rv. Additionally, CAS1 strains with RD149 deletions induced more TNFα secretion than those without deletions (p?=?0.013). CAS1 RD149 deletion strains from extrapulmonary sources showed more rapid growth and induced lower levels of TNFα and IL6 secretion in THP-1 cells than isolates from pulmonary sources. This data suggests that presence of RD149 reduces growth and increases the induction of TNFα in host cells by CAS1 strains. Differences observed for extrapulmonary strains may indicate an adaptation which increases potential for dissemination and tropism outside the lung. Overall, we hypothesise that RD149 deletions generate genetic diversity within strains and impact interactions of CAS1 strains with host cells with important clinical consequences.  相似文献   
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