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Characterization of microsatellites is extremely important for the development of molecular markers. Here, we present the detection and abundance of microsatellites or simple sequence repeats (SSRs) in UniGene sequences of Citrus sinensis. A total of 427 SSRs were mined in 8786 UniGene sequences downloaded from National Center for Biotechnology Information (NCBI). Depending on the repeat units, the length of SSRs ranged from 14 to 21 for mono-, 14 to 48 for di-, 18 to 48 for tri-, 24 to 40 for tetra- and 42 bp for hexa-nucleotide repeats. Average density of SSRs (1SSR/12.92 kb of 5518.71 kb sequences mined) suggests that only 4.43% of sequences contained SSRs. Di-nucleotide repeats were most frequent repeat type (49.41%) followed by tri-nucleotide repeats (41.45%). An attempt was made to design primer pairs for 427 identified SSRs but these were found only for 216 sequences. The positions of SSRs with respect to open reading frame (ORF) detected and annotation of sequences containing SSRs were also carried out to assign function to each of the sequences.  相似文献   
3.
This study aims to examine the effects of long‐term fertilization and cropping on some chemical and microbiological properties of the soil in a 32 y old long‐term fertility experiment at Almora (Himalayan region, India) under rainfed soybean‐wheat rotation. Continuous annual application of recommended doses of chemical fertilizer and 10 Mg ha–1 FYM on fresh‐weight basis (NPK + FYM) to soybean (Glycine max L.) sustained not only higher productivity of soybean and residual wheat (Triticum aestivum L.) crop, but also resulted in build‐up of total soil organic C (SOC), total soil N, P, and K. Concentration of SOC increased by 40% and 70% in the NPK + FYM–treated plots as compared to NPK (43.1 Mg C ha–1) and unfertilized control plots (35.5 Mg C ha–1), respectively. Average annual contribution of C input from soybean was 29% and that from wheat was 24% of the harvestable aboveground biomass yield. Annual gross C input and annual rate of total SOC enrichment from initial soil in the 0–15 cm layer were 4362 and 333 kg C ha–1, respectively, for the plots under NPK + FYM. It was observed that the soils under the unfertilized control, NK and N + FYM treatments, suffered a net annual loss of 5.1, 5.2, and 15.8 kg P ha–1, respectively, whereas the soils under NP, NPK, and NPK + FYM had net annual gains of 25.3, 18.8, and 16.4 kg P ha–1, respectively. There was net negative K balance in all the treatments ranging from 6.9 kg ha–1 y–1 in NK to 82.4 kg ha–1 y–1 in N + FYM–treated plots. The application of NPK + FYM also recorded the highest levels of soil microbial‐biomass C, soil microbial‐biomass N, populations of viable and culturable soil microbes.  相似文献   
4.
Leaching of pesticides in tea brew.   总被引:2,自引:0,他引:2  
A cup of tea that cheers can also be an important route of human exposure to pesticide residues. It is important to evaluate the percent transfer of pesticide residue from dried (made) tea to tea infusion, as tea is subjected to an infusion process prior to human consumption. To investigate the pesticide translocation, 13 pesticides commonly used on tea were studied by subjection of fortified teas to infusion. Analytes of interest were quantified by gas-liquid chromatography with nitrogen-phosphorus and electron capture detectors. Interestingly, water solubility of pesticides did not necessarily indicate a shift of residues toward their preferential accumulation in infusion. The pesticides with larger partition coefficient (K(ow)) values remained nonextractable in infusing water. Further, boiling for longer periods (extended brewing time) resulted in higher transfer of pesticides to tea brew.  相似文献   
5.
The neutral lipid of desilked eri silkworm pupae (Samia cynthia ricini) grown on two different host plants, castor (Ricinus communis Linn.) and tapioca (Manihot utilizsima Phol.) leaves, was extracted with hexane. The oil content in pupae was estimated to be in the range of 18-20% (dry basis). The pupal oil was found to be enriched with alpha-linolenic acid (ALA) with palmitic acid as the second major fatty acid. The level of ALA in the oil of silkworm pupae was found to be significantly higher (P < 0.001) when grown on tapioca (58.3%) as compared to those grown on castor (42.9%). Other chemical parameters such as percent free fatty acid, peroxide value, phosphorus content, percent unsaponifiable matter, and composition of sterols were also determined in both of the oils and compared. Reversed-phase high-performance liquid chromatography analysis of triacylglycerol molecular species showed that the pupal oil is rich in molecular species with equivalent carbon numbers (ECN) C36, C40, C42, C44, and C48. There was a significantly higher level (P < 0.001) of trilinolenin (C36) in the oil of tapioca-based silkworm as compared to castor-based silkworm pupae. Regiospecific analysis of the oil showed a higher level of ALA at the sn-2 position of silkworm pupae grown on tapioca (60.2%) as compared to those grown on castor (47.3%) oil. Thus, the presence of a large amount of ALA and their predominance at the sn-2 position make the eri pupal oil highly nutritious, provided that the oxidative stability is ensured.  相似文献   
6.
The oxidant/antioxidant balance of rabbits naturally infected with Psoroptes cuniculi and treated with ivermectin +/− vitamins A, D3, E, and H supplementation was investigated. Two groups of seven mixed ♂ and ♀, 6-to-8 month-old New Zealand White rabbits, diagnosed Psoroptes mites-positive by skin scraping examination and seven clinically healthy control rabbits were examined. Blood samples were obtained on day 0 and at 28 days post-therapy to determine oxidative stress indices. On day 0, the levels of lipid peroxides were significantly higher (P ≤ 0.01) in the Psoroptes-infected rabbits compared with the healthy controls while those of reduced glutathione and the activities of the antioxidant enzymes glutathione peroxidase, glutathione-S-transferase, catalase, and superoxide dismutase were significantly lower (P ≤ 0.01). Vitamin supplementation of the ivermectin-treated rabbits revealed both faster clinical (14 days) and parasitological (10 days) recovery. It was concluded that significant alteration of oxidant/antioxidant balance is a factor in the pathogenesis of P. cuniculi infestation of rabbits, and recovery can be enhanced by combining ivermectin treatment with vitamin A, D3, E, and H supplementation.  相似文献   
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8.
Two experiments, one short-term and one long-term, were conducted to elucidate the acute and chronic effects, respectively, of endosulfan exposure on the haemato-immunological and histopathological responses of Channa puncatatus. In the short-term study, fish were exposed to sublethal endosulfan (8.1 μg l−1) for 12, 24, 36, 48, 72 and 96 h. In the long-term study, fish were fed with normal diet and simultaneously either exposed to endosulfan (1.2 μg l−1) for 90 days or not. Results showed that the ascorbic acid levels in both the liver and the muscle decreased significantly (P < 0.05) by acute and chronic endosulfan exposure. The haemoglobin (Hb) level reduced significantly (P < 0.05) by 15.5% within 12 h of acute endosulfan exposure, further decreased by 25.8% after 24 h of exposure, however, thereafter the values increased and at the end of 72 h returned to normal levels. Almost similar trend was observed for the erythrocyte (RBC) count. The WBC count and the nitroblue tetrazolium (NBT) value showed a general increasing trend with increase in the duration of acute endosulfan exposure. The chronic exposure of C. punctatus to endosulfan significantly (P < 0.05) lowered the Hb level, RBC and WBC counts, NBT reduction value and the plasma parameters such as plasma protein, albumin (A) and globulin (G) compared with that of the control (except for A/G ratio). Endosulfan exposure also severely altered the liver histological structure. Overall results indicated that both short-term acute and long-term chronic endosulfan exposure had a significant impact on the haemato-immunological parameters and tissue histopathology of C. punctatus.  相似文献   
9.
Brucella abortus, a gram negative, facultative intracellular pathogen causes brucellosis in many animal species and humans. Although live, attenuated vaccines are available against this infection, they suffer from certain limitations. Therefore, the development of an effective subunit vaccine against brucellosis is an area of intense research. The outer membrane proteins (OMPs) of Brucella species have been extensively studied for its immunogenicity and protective ability. We have investigated the potential of CpG ODN to enhance the immunogenicity and protective efficacy of recombinant 28 kDa outer membrane protein (rOMP28) of Brucella melitensis. The study demonstrated vigorous immunoglobulin G (IgG) response of OMP28. The administration of rOMP28 with CpG caused increased cell mediated immune response in terms of induced IgG2a, T-cell proliferation and up-regulation of type I cytokine expression. In contrast, the free antigen suppressed the interferon gamma (type I cytokine) production on in-vitro stimulation of spleenocytes. The result indicates the role of OMP28 in the down regulation of IFN-γ production. Moreover, the B. abortus S-19 vaccinated mice showed highest production of IL-4 and IFN-γ. The protective ability of the antigen was evaluated by systemic bacterial clearance after challenging the mouse with B. abortus 544 pathogen. The level of protection was significant in rOMP28+CpG treated mice but was lower than the required level. The results of the present study indicate that rOMP28 could be an immunogen capable of inducing both humoral and cellular immune response. The humoral response was biased towards Th1 type when it was co-administered with CpG.  相似文献   
10.
Lipase-catalyzed synthesis of lipophilic phenolic antioxidants was carried out with a concentrate of n-3 polyunsaturated fatty acids (PUFAs), recovered from oil extracted from salmon ( Salmon salar ) byproduct. Vanillyl alcohol and rutin were selected for the esterification reaction, and obtained esters yields were 60 and 30%, respectively. The antioxidant activities of the esters were compared with those of commercial butylated hydroxytoluene (BHT) and α-tocopherol using DPPH radical scavenging and thiobarbituric acid assays. In the DPPH assay, rutin esters showed better activity than vanillyl esters, and on the contrary in lipophilic medium, vanillyl esters were found to be superior to rutin esters. In bulk oil system, the antioxidant activities of rutin and vanillyl derivatives were lower than that of BHT and α-tocopherol, but in emulsion, they showed better activity than α-tocopherol. By attaching to natural phenolics, the PUFAs are protected against oxidation, and PUFA improves the hydrophobicity of the phenolic, which could enhance its function in lipid systems.  相似文献   
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