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11.
Oil cakes and their biotechnological applications--a review   总被引:1,自引:0,他引:1  
Oil cakes have been in use for feed applications to poultry, fish and swine industry. Being rich in protein, some of these have also been considered ideal for food supplementation. However, with increasing emphasis on cost reduction of industrial processes and value addition to agro-industrial residues, oil cakes could be ideal source of proteinaceous nutrients and as support matrix for various biotechnological processes. Several oil cakes, in particular edible oil cakes offer potential benefits when utilized as substrate for bioprocesses. These have been utilized for fermentative production of enzymes, antibiotics, mushrooms, etc. Biotechnological applications of oil cakes also include their usages for vitamins and antioxidants production. This review discusses various applications of oil cakes in fermentation and biotechnological processes, their value addition by implementation in feed and energy source (for the production of biogas, bio-oil) as well.  相似文献   
12.
In the analysis of complex traits, congenic strains are powerful tools because they allow characterization of a single locus in the absence of genetic variation throughout the remainder of the genome. Here, we report the construction and initial characterization of a genome-wide panel of congenic strains derived from the donor strain DBA/2J on the background strain C57BL/6J. For many strains, we have carried out high-density SNP genotyping to precisely map the congenic interval and to identify any contaminating regions. Certain strains exhibit striking variation in litter size and in the ratio of females to males. We illustrate the utility of the set by "Mendelizing" the complex trait of myocardial calcification. These 65 strains cover more than 95% of the autosomal genome and should facilitate the analysis of the many genetic trait differences that have been reported between these parental strains.  相似文献   
13.
Maximum antiinflammatory activity of phytic acid (PA) was seen at an oral dose of 150 mg/kg in the carrageenan induced rat paw edema model. Although PA showed ability to prevent denaturation of proteins, it showed less antiinflammatory activity than ibuprofen. Ability of PA to bring down thermal denaturation of proteins might be a contributing factor in the mechanism of action against inflammation. PA, at all the doses tested, showed significant protection from ulcers induced by ibuprofen, ethanol and cold stress, with a maximum activity at 150 mg/kg. There was a significant increase in gastric tissue malondialdehyde levels in ethanol treated rats but these levels decreased following PA pretreatment. Moreover, pretreatment with PA significantly inhibited various effects of ethanol on gastric mucosa, such as, reduction in the concentration of nonprotein sulfhydryl groups, necrosis, erosions, congestion and hemorrhage. These results suggested that gastro-protective effect of PA could be mediated by its antioxidant activity and cytoprotection of gastric mucosa.  相似文献   
14.
15.
Solar ultraviolet (UV) radiation-induced oxidative stress has been implicated in various skin diseases. Here, we report the photoprotective effect of grape seed proanthocyanidins (GSPs) on UV-induced oxidative stress and activation of mitogen-activated protein kinase (MAPK) and NF-kappaB signaling pathways using normal human epidermal keratinocytes (NHEK). Treatment of NHEK with GSPs inhibited UVB-induced hydrogen peroxide (H2O2), lipid peroxidation, protein oxidation, and DNA damage in NHEK and scavenged hydroxyl radicals and superoxide anions in a cell-free system. GSPs also inhibited UVB-induced depletion of antioxidant defense components, such as glutathione peroxidase, catalase, superoxide dismutase, and glutathione. As UV-induced oxidative stress mediates activation of MAPK and NF-kappaB signaling pathways, we determined the effects of GSPs on these pathways. Treatment of NHEK with GSPs inhibited UVB-induced phosphorylation of ERK1/2, JNK, and p38 proteins of the MAPK family at the various time points studied. As UV-induced H2O2 plays a major role in activation of MAPK proteins, NHEK were treated with H2O2 with or without GSPs and other known antioxidants, viz. (-)-epigallocatechin-3-gallate, silymarin, ascorbic acid, and N-acetylcysteine. It was observed that H2O2-induced phosphorylation of ERK1/2, JNK, and p38 was decreased by these antioxidants. Under identical conditions, GSPs also inhibited UVB-induced activation of NF-kappaB/p65, which was mediated through inhibition of degradation and activation of IkappaBalpha and IKKalpha, respectively. Together, these results suggest that GSPs could be useful in the attenuation of UV-radiation-induced oxidative stress-mediated skin diseases in human skin.  相似文献   
16.
The whole plant aqueous extract of Coronopus didymus Linn. was fractionated on the basis of polarity and resulting fractions were evaluated for free radical scavenging ability. The most non-polar fraction (CDF1) was found to be more active than other fractions in scavenging DPPH, ABTS(-), nitric oxide and hydroxyl radicals in steady-state conditions. Stop-flow spectrometric studies showed 58.13% inhibition of 100 microM DPPH at a concentration of 150 microg/ml of CDF1 in 1000 s and 32.31% scavenging of 960 microM ABTS(-) at a concentration of 300 microg/ml of CDF1 in 100 s. The reaction of CDF1 with hydroxyl radicals produced by pulse radiolysis showed a transient spectrum with absorption peaks at 320, 390 and 400 nm, indicating the presence of flavonoids/related components. Competition kinetics with potassium thiocyanate against scavenging of hydroxyl radicals showed a reactivity of 0.1326 against thiocyanate. CDF1 also protected against Fenton reagent-induced calf thymus DNA damage at a concentration of 400 mg/ml indicating it to be the most potent fraction.  相似文献   
17.
Four antagonists bacteria namely, Bacillus megaterium MB3, B. subtilis MB14, B. subtilis MB99 and B. amyloliquefaciens MB101 were able to produce chitinase, β-1,3-glucanase and protease in different range with the presence of Rhizoctonia solani cell wall as a carbon source. Amplification of chitinase (chiA) gene of 270 bp and β-1, 3-glucanase gene of 415 bp was given supportive evidence at molecular level of antibiosis. After in vitro screening, all antagonists were tested against R. solani under greenhouse conditions. Root treatment of Bacillus strains showed superior defense during pathogen suppression in terms of chitinase, glucanase, peroxidase, poly phenol oxidase, phenylalanine ammonia-lyase activity and total phenolic content in leaves of tomato. All these enzymes accumulated high in tomato leaves as compared to roots. Pathogenesis-related proteins and defense-related enzymes accumulation was directly correlated with plant protection and greenhouse results indicated that B. amyloliquefaciens MB101- and B. subtilis MB14-treated plants offered 69.76 and 61.51 % disease reductions, respectively, over the infected control. These results established that these organisms have the potential to act as biocontrol agents. This study could be highlighted a mutual importance of liquid formulation of antagonistic Bacillus spp. against root associated sclerotia former pathogen R. solani.  相似文献   
18.
Oxidative stress plays a critical role in the pathophysiology of cardiac failure, including the modulation of neovascularization following myocardial infarction (MI). Redox molecules thioredoxin (Trx) and glutaredoxin (Grx) superfamilies actively maintain intracellular thiol-redox homeostasis by scavenging reactive oxygen species. Among these two superfamilies, the pro-angiogenic function of Trx-1 has been reported in chronic MI model whereas similar role of Grx-1 remains uncertain. The present study attempts to establish the role of Grx-1 in neovascularization and ventricular remodeling following MI. Wild-type (WT) and Grx-1 transgenic (Grx-1(Tg/+)) mice were randomized into wild-type sham (WTS), Grx-1(Tg/+) Sham (Grx-1(Tg/+)S), WTMI, Grx-1(Tg/+)MI. MI was induced by permanent occlusion of the LAD coronary artery. Sham groups underwent identical time-matched surgical procedures without LAD ligation. Significant increase in arteriolar density was observed 7 days (d) after surgical intervention in the Grx-1(Tg/+)MI group as compared to the WTMI animals. Further, improvement in myocardial functional parameters 30 d after MI was observed including decreased LVIDs, LVIDd, increased ejection fraction and, fractional shortening was also observed in the Grx-1(Tg/+)MI group as compared to the WTMI animals. Moreover, attenuation of oxidative stress and apoptotic cardiomyocytes was observed in the Grx-1(Tg/+)MI group as compared to the WTMI animals. Increased expression of p-Akt, VEGF, Ang-1, Bcl-2, survivin and DNA binding activity of NF-κB were observed in the Grx-1(Tg/+)MI group when compared to WTMI animals as revealed by Western blot analysis and Gel-shift analysis, respectively. These results are the first to demonstrate that Grx-1 induces angiogenesis and diminishes ventricular remodeling apparently through neovascularization mediated by Akt, VEGF, Ang-1 and NF-κB as well as Bcl-2 and survivin-mediated anti-apoptotic pathway in the infarcted myocardium.  相似文献   
19.
Several potential sources of reactive oxygen species (ROS) in cells exist. One source is NADPH oxidase, which is especially important for superoxide radical production. Nox2 is a primary regulatory subunit of NADPH oxidase. In the present study, we examined the role of ROS and NADPH oxidase in ischemic preconditioning (IP)-mediated cardioprotection by using Nox2(-/-) mice. Both wild-type (WT) and Nox2(-/-) mice were subjected to either 30?min of ischemia followed by 2?h of reperfusion (IR) or IP prior to 30?min ischemia and 2?h of reperfusion. Reduction in left ventricular developed pressure (60.1 versus 63?mmHg), dp/dt (max) (893 versus 1,027?mmHg/s), and aortic flow (0.9 versus 1.8?ml/min) was observed in Nox2(-/-)IPIR compared to WTIPIR along with increased infarct size (33% versus 22%) and apoptosis after 120?min of reperfusion. Differentially regulated genes were demonstrated by comparing gene expression in WTIPIR versus Nox2(-/-) IPIR hearts. Selected differentially regulated genes such as β-catenin, SRPK3, ERDR1, ACIN1, Syntaxin-8, and STC1 were validated by real-time PCR. Taken together, this is the first report identifying important, differentially expressed genes during ischemic preconditioning in Nox2(-/-) mice by using microarray analysis.  相似文献   
20.
Three novel collagen VI chains with high homology to the alpha3 chain   总被引:1,自引:0,他引:1  
Here we describe three novel collagen VI chains, alpha4, alpha5, and alpha6. The corresponding genes are arranged in tandem on mouse chromosome 9. The new chains structurally resemble the collagen VI alpha3 chain. Each chain consists of seven von Willebrand factor A domains followed by a collagenous domain, two C-terminal von Willebrand factor A domains, and a unique domain. In addition, the collagen VI alpha4 chain carries a Kunitz domain at the C terminus, whereas the collagen VI alpha5 chain contains an additional von Willebrand factor A domain and a unique domain. The size of the collagenous domains and the position of the structurally important cysteine residues within these domains are identical between the collagen VI alpha3, alpha4, alpha5, and alpha6 chains. In mouse, the new chains are found in or close to basement membranes. Collagen VI alpha1 chain-deficient mice lack expression of the new collagen VI chains implicating that the new chains may substitute for the alpha3 chain, probably forming alpha1alpha2alpha4, alpha1alpha2alpha5, or alpha1alpha2alpha6 heterotrimers. Due to a large scale pericentric inversion, the human COL6A4 gene on chromosome 3 was broken into two pieces and became a non-processed pseudogene. Recently COL6A5 was linked to atopic dermatitis and designated COL29A1. The identification of novel collagen VI chains carries implications for the etiology of atopic dermatitis as well as Bethlem myopathy and Ullrich congenital muscular dystrophy.  相似文献   
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