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991.
Cline Moriou Damien Lacroix Sylvain Petek Amr El-Demerdash Rozenn Trepos Tinihauarii Mareva Leu Cristina Florean Marc Diederich Claire Hellio Ccile Debitus Ali Al-Mourabit 《Marine drugs》2021,19(3)
Chemical investigation of the South-Pacific marine sponge Suberea clavata led to the isolation of eight new bromotyrosine metabolites named subereins 1–8 (2–9) along with twelve known co-isolated congeners. The detailed configuration determination of the first representative major compound of this family 11-epi-fistularin-3 (11R,17S) (1) is described. Their chemical characterization was achieved by HRMS and integrated 1D and 2D NMR (nuclear magnetic resonance) spectroscopic studies and extensive comparison with literature data. For the first time, a complete assignment of the absolute configurations for stereogenic centers C-11/17 of the known members (11R,17S) 11-epi-fistularin-3 (1) and 17-deoxyfistularin-3 (10) was determined by a combination of chemical modifications, Mosher’s technology, and ECD spectroscopy. Consequently, the absolute configurations of all our new isolated compounds 2–9 were determined by the combination of NMR, Mosher’s method, ECD comparison, and chemical modifications. Interestingly, compounds 2–7 were obtained by chemical transformation of the major compound 11-epi-fistularin-3 (1). Evaluation for acetylcholinesterase inhibition (AChE), DNA methyltransferase 1 (DNMT1) modulating activity and antifouling activities using marine bacterial strains are also presented. 相似文献
992.
993.
We evaluated the factors influencing the adoption of rice-fish farming in the Tavalesh region near the Caspian Sea in northern Iran.We conducted a survey with open-ended questions.Data were collected from 184 respondents(61 adopters and 123 non-adopters) randomly sampled from selected villages and analyzed using logistic regression and multi-response analysis.Family size,number of contacts with an extension agent,participation in extension-education activities,membership in social institutions and the presence of farm workers were the most important socio-economic factors for the adoption of rice-fish farming system.In addition,economic problems were the most common issue reported by adopters.Other issues such as lack of access to appropriate fish food,losses of fish,lack of access to high quality fish fingerlings and dehydration and poor water quality were also important to a number of farmers. 相似文献
994.
利用RT-PCR方法从大豆根部组织获得Glyma03g34310.1开放阅读框(ORF)全长, 经测序验证、Blast比对与同源性分析发现该序列编码的蛋白质与其他植物的TIP1;1蛋白具有较高的相似性, 故命名为GmTIP1;1基因(GenBank登录号为AK285481), 该基因ORF长753 bp, 编码1个包含250个氨基酸的蛋白, 在ORF内部第381个核苷酸处含有1个94 bp的内含子, 符合↓GT--AG↓的剪接方式; 系统进化树分析发现Gm TIP1;1聚类到豆科植物分支, 其他不同科的植物也有规律地聚到了不同分支, 推测该蛋白氨基酸序列可以作为植物分类的依据; 半定量RT-PCR结果表明该基因在大豆的不同器官、不同器官的不同发育阶段均具较高且同等的表达水平, 暗示该基因在植物的整个发育进程中均具重要作用; 在盐胁迫的不同时间点其表达量有下降的趋势, 但仍然保持较高的表达水平; 以pYES2为酵母表达载体, 转化酿酒酵母INVSc1菌株, 获得重组酵母INVSc1 (pYES2-GmTIP1;1), 转化菌株在盐胁迫下的存活率明显高于对照INVSc1 (pYES2), 而在干旱胁迫下则没有显著差异, 表明该基因的表达能有效地提高酵母的耐盐性。 相似文献
995.
AnnaLotta Schiller Vestergren Sofia Trattner Jinfeng Pan Pernilla Johnsson Afaf Kamal-Eldin Eva Brännäs Ali A. Moazzami Jana Pickova 《Aquaculture International》2013,21(4):843-859
Sesamin (S) is a known lipid modulator and has been shown to increase the conversion of α-linolenic acid (ALA) to docosahexaenoic acid in rainbow trout (Oncorhynchus mykiss) fed vegetable oil mixtures including linseed oil. In this study, we evaluated the effects of S supplementation in linseed oil-based diets, content of α- and γ-tocopherols, fatty acid (FA) composition, as well as the gene expression of lipid-related genes. Fish with an average weight of 36.5 g were fed different combinations of commercial linseed oil (LO), purified linseed oil triacylglycerols (TAG) with polar fraction removed and a mixed linseed-sunflower oil (6:4 v/v) (MO). S was added at 0.58 g 100?1g feed and fed to the fish for a period of 58 days. Expression of PPARα was downregulated in white muscle of fish fed S containing diets (P < 0.05). The expression of PPARβ1A was not affected by S supplementation except where TAG oil was used. The expression of PPARβ1A declined significantly in TAG + S fed group (P < 0.05), which indicates that some minor compounds in linseed oil might suppress the effect of S on the expression of PPARβ1A. The expression of PPARγ(long) declined in LO + S and MO + S fed group (P < 0.05). The β-oxidation-related genes CPT1 and ACO were upregulated by vegetable oils compared to fish oil. S decreased percentage of ALA in white muscle of fish fed LO + S (P < 0.05). The increased desaturation index and the decreased ALA levels suggest that S may increase the biosynthesis of highly unsaturated FA in rainbow trout. 相似文献
996.
Mahmoudreza Ovissipour Ali Motamedzadegan Barbara Rasco Rajab Mohammad Nazari 《Journal Of Aquatic Food Product Technology》2013,22(2):148-159
Protein hydrolysates were prepared from yellowfin tuna viscera using Alcalase®. Response surface methodology (RSM) was applied to study the effect of independent variables, enzyme activity, temperature, and time on the protein recovery (PR) as the response. The coefficient of determination (r2 = 98%) was satisfactory, and the lack of fit test showed a non-significant value for the PR model equation, indicating that the regression equation was adequate for predicting the PR under tested combinations of values. Enzyme activity at 79.9 AU/kg protein, temperature at 59.9°C, and the time of 105 min were found to be the optimum conditions to reach the highest PR (85%). Considerable soluble protein was released with increasing degree of hydrolysis (DH). The yellowfin tuna visceral hydrolysates' amino acids profiles showed high essential amino acids content, although lysine, methionine, and phenylalanine were limited. In addition, the results showed that with increasing hydrolysis time, the amino acids increased. Yellowfin tuna visceral hydrolysates were rich in flavor amino acids which can be used as a taste enhancer. 相似文献
997.
Yasaman Etemadian Alireza Sadeghi Mahoonak Ali Shabani 《Journal Of Aquatic Food Product Technology》2013,22(5):449-459
The use of polyphosphates as a partial replacement of salt in different meat products to improve water holding capacity yield and retard oxidative rancidity has been noticed for many years. Therefore, in this study, effects of polyphosphates dip treatment in 5% solution with three different compounds of phosphate—including tetrasodium pyrophosphate (TSPP), sodium tripolyphosphate (STPP), and a mixture of them on kutum (Rutilus frisii kutum) fillets stored in ice was investigated for 18 days. Phosphate pretreatments showed desirable modal effects on fillets. In particular, the use of TSPP and the mixture of TSPP and STPP solutions were found to delay the fish fillet color changes and improved textural characteristics. An increase in water holding capacity accompanied with a decrease in hardness was observed in samples pretreated with polyphosphates. In total, the results indicated that dipping kutum fillets in polyphosphates solution was the most effective method to improve the quality properties of fillets during ice storage when compared with other phosphate-treated groups. 相似文献
998.
Farming of the striped catfish, Pangasianodon hypophthalmus, is a major aquaculture activity in Bangladesh, particularly in the district of Mymensingh. However, pangasius farm management practices and the socio‐economic impacts of pangasius farming systems in Mymensingh have not yet been adequately described in the literature. This article provides an overview of the present status and characteristics of pangasius culture in Bangladesh based on data from a study conducted in Mymensingh district during 2009. The mean productivity of pangasius was 36.9 MT ha?1, where 87.9% of the farms produced between 15 and 65 MT ha?1 of pangasius, with an additional 10–20% Indian major and Chinese carps and Nile tilapia. Pangasius aquaculture in Bangladesh has improved the economic and social status of a variety of stakeholders in communities where the fish is farmed. 相似文献
999.
Md Mahbubul Hassan Md Nahiduzzaman Shaheed Nasrullah Al Mamun Md Abu Taher Mostafa Ali Reza Hossain 《Aquaculture Research》2013,45(1):150-158
This study reports on the spermatological properties, and on the development of a protocol for refrigerator storage (4°C) of Labeo calbasu (Hamilton, 1822) sperm for artificial breeding. Volume, motility, concentration and pH of the freshly collected sperm were 2.21 ± 0.53 (μL g?1 of fish weight) (mean ± SD), 95 ± 1 (%), 1.93 ± 0.44 × 109 (cells mL?1) and 7.56 ± 0.17 respectively. Sperm activation was evaluated at different osmolalities of NaCl solution, and motility ceased completely when osmolality of the extender was ≥287 mOsmol kg?1. Sperm retained motility for 24, 72 and 108 h, after refrigerator storage when sperm were undiluted, suspended in Alsever's solution and suspended in Alsever's solution containing 5% methanol respectively. Fertilization rate of fresh eggs with sperm stored at 4°C in Alsever's solution and Alsever's solution containing 5% methanol was 77% and 60% with a hatching rate of 60% and 43% respectively. The fertilization and hatching success of the stored sperm suggests potential to use refrigeration for transporting genetic material to hatcheries for artificial breeding of L. calbasu in Bangladesh. 相似文献
1000.
Khanaki K Nouri M Ardekani AM Ghassemzadeh A Shahnazi V Sadeghi MR Darabi M Mehdizadeh A Dolatkhah H Saremi A Imani AR Rahimipour A 《Iranian Biomedical Journal》2012,16(1):38-43
Background: Endometriosis is a common chronic inflammation causing major problems including infertility. The role of omega-3 and omega-6 fatty acids as their potential anti-inflammatory effects in endometriosis needs to be further explored. The objective of this study was to compare serum phospholipid fatty acid profile in endometriosis patients with controls, and to explore the correlation of this profile with the severity of the disease. Methods: Sixty-four endometriosis patients and 74 control women, in reproductive age, participated in this study. Among the endometriosis patients, 19 cases were in stage I, 27 cases in stage II, 8 cases in stage III, and 10 cases in stage IV. Each patient underwent laparoscopy. Before surgery, 5 ml of blood was obtained. After extraction of the total lipids, serum total phospholipid fraction was isolated by thin layer chromatography. Fatty acid composition of the phospholipid fraction was determined by gas chromatography and the resulted profile was compared in endometriosis patients and controls. The profile was also compared in the endometriosis group based on the severity of disease. Results: Stearic acid was significantly lower in the endometriosis group as compared to controls (P= 0.030). No other fatty acid compositions were significantly different between patients and controls. Serum ratio of eicosapentaenoic acid (EPA) to arachidonic acid (AA) was in reasonable correlation with the severity of endometriosis (r = 0.34, P = 0.006). Conclusion: According to these findings, levels of fatty acids in serum total phospholipids seem not to be a marker for endometriosis, but the EPA to AA ratio was a relevant factor indicating severity of illness.Key Words: Endometriosis, Phospholipids, Omega-3 fatty acids 相似文献