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1.
Photoirradiation of soy oil with UV/visible light has been shown to produce significant amounts of trans,trans conjugated linoleic acid (CLA) isomers through conversion of various synthesized intermediate cis,trans isomers. The objective of this study was to determine the kinetics of CLA isomers synthesis to better understand the production of various isomers. Soy oil was irradiated with UV/visible light for 144 h in the presence of an iodine catalyst and CLA isomers analyzed by gas chromatography (GC). Arrhenius plots were developed for the conversion of soy oil linoleic acid (A) to form cis-, trans/trans-, cis-CLA (B), conversion of cis-, trans/trans-, cis-CLA to form trans,trans-CLA (C) with respect to B, and formation of trans,trans-CLA isomers with respect to C. The kinetics of consumption of linoleic acid (LA) to form cis-, trans/trans-, cis-CLA was found to be of second-order with a rate constant of 9.01 x 10-7 L/mol s. The rate of formation of cis-, trans/trans-, cis-CLA isomers depends on the rate of formation from LA and its rate of consumption to form trans,trans-CLA isomers. The conversion of cis-, trans/trans-, cis-CLA isomers to trans,trans-CLA isomers was found to be of first-order with a rate constant of 2.75 x 10-6 s-1. However, the formation of thermodynamically stable trans,trans-CLA isomers (C) with respect to C was found to be a zero-order reaction with a rate constant of 10.66 x 10-7 mol/L s. The consumption of LA was found to be the rate-determining step in the CLA isomers formation reaction mechanism. The findings provide a better understanding of the mechanism of CLA isomers synthesis by photoirradiation and the factors controlling the ratio of various isomers. 相似文献
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Thakur Manisha Luharch Rakshandha Sharma Vishal Sharma Dharam Paul 《Genetic Resources and Crop Evolution》2022,69(2):567-575
Genetic Resources and Crop Evolution - Santa Rosa and Frontier are the major Japanese plum (Prunus salicina Lindl.) cultivars grown throughout the world. The present investigation was performed to... 相似文献
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Vishal Singh Ashish TewariSatya P.S. Kushwaha Vinay K. Dadhwal 《Forest Ecology and Management》2011,261(11):1945-1949
Biomass and carbon sequestration rate of a young (four year old) mixed plantation of Dalbergia sissoo Roxb., Acacia catechu Willd., and Albizia lebbeck Benth. growing in Terai region (a level area of superabundant water) of central Himalaya was estimated. The plantation is seed sown in the rainy season of year 2004 and spread over an area of 44 ha. Allometric equations for both above and below ground components were developed for three tree species. The density of trees in the plantation was 1322 trees ha−1 The diameters of trees were below 10 cm. Five diameter classes were defined for D. sissoo and A. catechu and 3 for A. lebbeck. 5 trees were harvested in each diameter class. Individual tree allometry was exercised for developing the allometric equations relating tree component (low and above ground) biomass to d.b.h. Post analysis equations were highly significant (P > 0.001) for each component of all species. In the plantation Holoptelia integrifolia Roxb. (Family Ulmaceae) has been reduced to shrub form because of frost. Only the aboveground biomass of H. integrifolia and other shrubs were estimated by destructive harvesting method. Herbaceous forest floor biomass and leaf litter fall were also estimated. The total forest vegetation biomass was 10.86 Mg ha−1 in 2008 which increased to 19.49 Mg ha−1 in 2009. The forest is sequestering carbon at the rate of 4.32 Mg ha−1 yr−1. 相似文献
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Subhash Verma Mandeep Sharma Shailja Katoch Lovit Verma Sandeep Kumar Vishal Dogra Rajesh Chahota Prasenjit Dhar Geetanjali Singh 《Veterinary research communications》2013,37(1):83-89
Pasteurella multocida is a causative agent of many major diseases of which haemorrhagic septiciemia (HS) in cattle & a buffalo is responsible for significant losses to livestock sector in India and south Asia. The disease outcome is affected by various host- and pathogen-specific determinants. Several bacterial species-specific putative virulence factors including the capsular and virulence associated genes have been proposed to play a key role in this interaction. A total of 23 isolates of P. multocida were obtained from 335 cases of various clinically healthy and diseased cattle. These isolates were examined for capsule synthesis genes (capA, B, D, E and F) and eleven virulence associated genes (tbpA, pfhA, toxA, hgbB, hgbA, nanH, nanB, sodA, sodC, oma87 and ptfA) by PCR. A total of 19 P. multocida isolates belonging to capsular type B and 4 of capsular type A were isolated. All isolates of capsular type B harboured the virulence associated genes: tbpA, pfhA, hgbA, sodC and nanH, coding for transferrin binding protein, filamentous hemagglutinin, haemoglobin binding protein, superoxide dismutase and neuraminidases, respectively; while isolates belonging to capsular type A also carried tbpA, pfhA, hgbA and nanH genes. Only 50 % of capsular type A isolates contained sodC gene while 100 % of capsular type B isolates had sodC gene. The gene nanB and toxA were absent in all the 23 isolates. In capsular type A isolates, either sodA or sodC gene was present & these genes did not occur concurrently. The presence of virulence associated gene ptfA revealed a positive association with the disease outcome in cattle and could therefore be an important epidemiological marker gene for characterizing P. multocida isolates. 相似文献
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Daily intake of conjugated linoleic acid (CLA), an anticarcinogenic, antiatherosclerotic, antimutagenic agent, and antioxidant, from dairy and meat products is substantially less than estimated required values. The objective of this study was to obtain CLA-rich soybean oil by a customized photochemical reaction system with an iodine catalyst and evaluate the effect of processing on iodine and iodo compounds after adsorption. After 144 h of irradiation, a total CLA yield of 24% (w/w) total oil was obtained with 0.15% (w/w) iodine. Trans,trans isomers (17.5%) formed the majority of the total yield and are also associated with health benefits. The isomers cis-9,trans-11 and trans-10,cis-12 CLA, associated with maximum health benefits, formed approximately 3.5% of the total oil. This amount is quite significant considering that total CLA obtained from dairy sources is only 0.6%. ATR-FTIR, 1H NMR, and GC-MS analyses indicated the absence of peroxide and aldehyde protons, providing evidence that secondary lipid oxidation products were not formed during the photochemical reaction. Adsorption processing vastly reduced the iodine and iodocompounds without CLA loss. Photocatalysis significantly increased the levels of CLA in soybean oil. 相似文献
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Radha Prasanna Vidhi Chaudhary Vishal Gupta Santosh Babu Arun Kumar Rajendra Singh Yashbir Singh Shivay Lata Nain 《European journal of plant pathology / European Foundation for Plant Pathology》2013,136(2):337-353
Cyanobacteria - phytopathogenic fungi - tomato plant interactions were evaluated for developing suitable biological options for combating biotic stress (Fusarium wilt) and enhancing plant vigour. Preliminary evaluation was undertaken on the fungicidal and hydrolytic enzyme activity of the cyanobacterial strains (Anabaena variabilis RPAN59, A. laxa RPAN8) under optimized environmental/nutritional conditions, followed by amendment in compost-vermiculite. Such formulations were tested against Fusarium wilt challenged tomato plants, and the Anabaena spp. (RPAN59/8) amended composts significantly reduced mortality in fungi challenged treatments, besides fungal load in soil. Cyanobacteria amended composts also led to an enhancement in soil organic C, nitrogen fixation, besides significant improvement in growth, yield, fruit quality parameters, N, P and Zn content. The tripartite interactions also enhanced the activity of defence and pathogenesis related enzymes in tomato plants. A positive correlation (r?=?0.729 to 0.828) between P content and pathogenesis/defense enzyme activity revealed their role in enhancing the resistance of the plant through improved nutrient uptake. Light and scanning electron microscopy (SEM) revealed cyanobacterial colonization, which positively correlated with reduced fungal populations. The reduced disease severity coupled with improved plant growth/ yields, elicited by cyanobacterial treatments, illustrated the utility of such novel formulations in integrated pest and nutrient management strategies for Fusarium wilt challenged tomato crop. 相似文献
7.
Y Liu V Javvaji SR Raghavan WE Bentley GF Payne 《Journal of agricultural and food chemistry》2012,60(36):8963-8967
This paper reports a simple, rapid, and sugar-selective method to induce gelation from glucose-containing samples. This method employs glucose oxidase (GOx) to selectively "recognize" and oxidize glucose to generate gluconic acid, which acts to solubilize calcium carbonate and release calcium ions. The release of calcium ions triggers gelation of the calcium-responsive polysaccharide alginate to form a calcium-alginate hydrogel. Rheological measurements confirm that gel formation is triggered by glucose but not fructose or sucrose (consistent with GOx's selectivity). Vial inversion tests demonstrate that gel formation can be readily observed without the need for instrumentation. Proof-of-concept studies demonstrate that this gel-forming method can detect glucose in food/beverage products sweetened with glucose or high-fructose corn syrups. These results indicate that the enzyme-induced gelation of alginate may provide a simple means to test for sweeteners using components that are safe for use on-site or in the home. 相似文献
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Vishal Mishra Chandrajit Balomajumder Vijay Kumar Agarwal 《Water, air, and soil pollution》2010,209(1-4):489-500
Present research has delineated the biosorption potential of three different nonliving biomasses namely eucalyptus bark saw dust, mango bark saw dust, and pineapple fruit peel with respect to Zn (II) ion removal from liquid phase through batch experiments. The efficacy of Zn (II) ion biosorption onto surface of biosorbents was judged and correlated with biosorbent particle size, surface chemistry, and surface texture. Maximum metal ion uptake capacity, percentage removal, and minimum equilibrium concentration as 1.688 mg/g, 84.4%, and 1.56 mg/l, respectively, was obtained using eucalyptus bark saw dust mediated biosorption followed by mango bark saw dust as 1.028 mg/g, 51.4%, and 4.867 mg/l and pineapple fruit peel as 0.45 mg/g, 22.9%, and 7.71 mg/l, respectively, at a particle size of 0.5 mm. Additionally, present investigation also proved that biosorption efficiency and metal ion interaction with adsorbent surface also depends upon presence of functional groups involved in metal ion adsorption and surface porosity. 相似文献