首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
One isolate of Brachiomonas submarina was tested for its ability to grow heterotrophicly on 5 different organic compounds. Sodium acetate and glucose were found to be effective in supporting the growth. Sodium acetate was chosen as the organic nutrient to test the combined effects of organic and inorganic solutions on the growth and fatty acid composition of Brachiomonas submarina. The best growth rates were achieved at 3 mmol L−1 CH3COONa and 0.88 mmol L−1 NaNO3 in heterotrophic condition, and 4 mmol L−1 CH3COONa and 3.52 mmol L−1 NaNO3 in mixotrophic condition. The differences between fatty acid contents were significant. The total polyunsaturated fatty acids (T. P. U. F. As) varied from 55.79% to 67.72% in heteritrophic growth and from 52.39% to 65.55% in mixotrophic growth. It is concluded that CH3COONa and NaNO3 at 3 mmol L−1 and 3.52 mmol L−1 should respectively be used in order to achieve the highest growth rate and fatty acid content.  相似文献   

2.
Lu  Lin  Wang  Jun  Yang  Guanpin  Zhu  Baohua  Pan  Kehou 《中国海洋湖沼学报》2017,35(2):303-312
Mass microalgal culture plays an irreplaceable role in aquaculture,but microalgal productivity is restricted by traditional autotrophic culture conditions.In the present study,a Tetraselmis chuii strain belonging to the phylum Chlorophyta was isolated from south Yellow Sea.The growth rate and biomass productivity of this strain was higher under mixotrophic conditions with different carbon:nitrogen(C:N)ratios than those under autotrophic conditions.When the C:N ratio was 16,the optical density and biomass productivity were 3.7-and 5-fold higher than their corresponding values under autotrophic culture conditions,respectively.Moreover,T.chuii synthesized more polysaccharides and total lipids under mixotrophic conditions.In addition,T.chuii cultured under mixotrophic conditions synthesized more types of fatty acids than autotrophic culture conditions.At a C:N ratio of 16,the percentage of C16:0 and C18:1 reached 30.08%and 24.65%of the total fatty acid(TFA) content,respectively.These findings may provide a basis for largescale mixotrophic culture of T.chuii,as a potential bait-microalga.  相似文献   

3.
Algal biotechnology has advanced greatly in the past three decades. Many microalgae are now cultivated to produce bioactive substances. Odontella aurita is a marine diatom industrially cultured in outdoor open ponds and used for human nutrition. For the first time, we have systematically investigated the effects of culture conditions in cylindrical glass columns and fiat-plate photobioreactors, including nutrients (nitrogen, phosphorus, silicon, and sulfur), light intensity and light path, on O. aurita cell growth and biochemical composition (protein, carbohydrate, β-1,3-glucan, lipids, and ash). The optimal medium for photoautotrophic cultivation of O. aurita contained 17.65 mmol/L nitrogen, 1.09 mmol/L phosphorus, 0.42 mmol/L silicon, and 24.51 mmol/L sulfur, yielding a maximum biomass production of 6.1-6.8 g/L and 6.7-7.8 g/L under low and high light, respectively. Scale-up experiments were conducted with fiat-plate photobioreactors using different light-paths, indicating that a short light path was more suitable for biomass production of O. aurita. Analyses of biochemical composition showed that protein content decreased while carbohydrate (mainly composed of 15-1,3-glucan) increased remarkably to about 50% of dry weight during the entire culture period. The highest lipid content (19.7% of dry weight) was obtained under 0.11 mmol/L silicon and high light conditions at harvest time. Fatty acid profiles revealed that 80% were Cx4, C~6, and C20, while arachidonic acid and eicosapentaenoic acid (EPA) accounted for 1.6%-5.6% and 9%-20% of total fatty acids, respectively. High biomass production and characteristic biochemical composition profiles make O. aurita a promising microalga for the production ofbioactive components, such as EPA and D-1,3-glucan.  相似文献   

4.
Batch experiments were conducted to study the effects of low-molecular-weight organic acids(LMWOAs) on desorption of Hg from two kinds of soils in the eastern Shandong Province,China.Of all LMWOAs,oxalic and citric acids were chosen as the representatives in this experiment because they are most common in soils.Desorption of Hg increases with the increase of extracting time,until the highest desorption amount at 6-8 h,and then declines.It indicates that timeliness is very important when organic acids are used for phytoremediation in contaminated soils.When the concentrations of organic acids increase from 1.0 mmol/L to 10.0 mmol/L,Hg desorption increases significantly regardless of oxalic or citric acid.Compared with oxalic acid,citric acid is more effective to enhance the desorption of Hg,especially from fluvo-aquic soil.With the increase of initial pH value from 3 to 8,Hg desorption decreases directly in the presence of oxalic acid.However,Hg desorption first decreases,then increases,and eventually decreases again in the presence of citric acid due to the variation of competitive ability between chelating of citric acid and adsorption of soil in different pH values.Citric acid showed greater ability to release Hg from soils than oxalic acid.According to the results of the present study,it is found that the bioavailabilities of heavy metal can be improved with selecting suitable types and concentrations of organic acid amendment and reasonable soil condition.  相似文献   

5.
1 INTRODUCTION Heavy metal pollution in marine environment has always been a serious problem over the last several decades, because most of the heavy metal species that enter marine environment accumulated there without decomposition. Strontium is a minor…  相似文献   

6.
用乙醇提取螺旋藻中的叶绿素,再用5%NaOH溶液皂化、石油醚萃取,在酸性环境中用10%CuSO4溶液实现铜镁置换,沉淀物经丙配溶解后,加2%NaOH的乙醇溶液成盐,过滤,水洗,真空干燥,制成叶绿素铜钠盐.制品的质量达到GB3262-82的要求.提取率为64.7%,制品得率占藻粉1.1%。着重对铜镁置换的条件、制品耐酸、耐热、耐光等性能进行了对比试验,结果表明整个工艺是切实可行的.  相似文献   

7.
TOTAL LIPID AND FATTY ACID COMPOSITION OF EIGHT STRAINS OF MARINE DIATOMS   总被引:3,自引:0,他引:3  
Fatty acid composition and total lipid content of 8 strains of marine diatoms (Nitzschia frustrula, Nitzschia closterium, Nitzschia incerta, Navicula pelliculosa, Phaeodactylum tricornutum, Synedra fragilaroides) were examined. The microalgae were grown under defined conditions and harvested at the late exponential phase. The major fatty acids in most strains were 14∶0 (1.0%–6.3%), 16∶0 (13.5–26.4%), 16∶1n−7 (21.1%–46.3%) and 20∶5n−3 (6.5%–19.5%). The polyunsaturated fatty acids 16∶2n−4, 16∶3n−4, 16∶4n−1 and 20∶4n−6 also comprised a significant proportion of the total fatty acids in some strains. The characteristic fatty acid composition of diatoms is readily distinguishable from those of other microalgal groups. Significant concentration of the polyunsaturated fatty acid 20∶5n−3 (eicosapentaenoic acid) was present in each strain, with the highest proportion in B222 (19.5%). Project supported by the Hi-Tech “863” Programs of the China Ministry of Science and Technology (863-819-02-01).  相似文献   

8.
研究了3种无机盐对隐甲藻(Crypthecodinium cohnii ATCC30556)生长及DHA产量的影响.结果表明隐甲藻可在NaCl为唯一无机盐的培养基中生长;培养基中NaCl质量浓度为6 g/L,Mg2+浓度为13.23 mmol/L,PO43-浓度为7.19 mmol/L可满足藻细胞生长和DHA积累的需求,此时隐甲藻有着最大的生物量和DHA产量,分别为3.31 g/L和499.93 mg/L.  相似文献   

9.
金枪鱼油的精炼工艺对脂肪酸组成的影响   总被引:1,自引:0,他引:1  
粗鱼油通过精炼可以除去非甘油三酯杂质成分,研究表明黄鳍金枪鱼鱼油精炼的工艺参数为:800 g/L的H3PO4脱胶,添加量为油量的1%(体积分数);300 g/L的NaOH脱酸,添加量为油量的2%(体积分数);活性土脱色,添加量为油量的10%(质量分数);85℃下减压蒸馏脱臭15 min。经过精炼,鱼油呈淡黄色,澄清透明,有淡鱼腥味,理化指标达到鱼油SC/T3502-2000标准的精制鱼油一级要求,精制鱼油中PUFA的总含量(w)达37.06%,DHA和EPA含量(w)分别为25.10%和4.45%。  相似文献   

10.
制备固体超强酸SO4 2 - /Fe2 O3,并测定其红外光谱。以乙酸和正丁醇为反应物、固体超强酸SO4 2 - /Fe2 O3为催化剂 ,进行合成乙酸丁酯的研究。实验结果表明 ,固体超强酸SO4 2 - /Fe2 O3在合成乙酸丁酯反应中的催化活性与浓硫酸相当 ,用 0 1mol正丁醇与 0 2mol乙酸反应 ,催化剂用量 0 3g ,回流时间 90min ,乙酸丁酯收率为 63 8%。  相似文献   

11.
新鲜鱼油中添加05、0、2505、00 mg/kg 4种不同浓度的维生素E醋酸酯,在实验的第6、14、28、36和68天测定鱼油中的脂肪酸含量。结果表明:在500 mg/kg添加量内,维生素E醋酸酯对鱼油中脂肪酸含量没有显著性影响(P>0.05)。在实验期间,EPA(C20:5)、DHA(C22:6)、亚油酸(C18:2)含量明显下降,ARA(C20:4)、亚麻酸(C18:3)先升后降,棕榈酸(C16:1)逐步上升;C14含量逐渐增加,C17则先降后升,C16和C18在实验后期有较大提高。维生素E醋酸酯对鱼油中不饱和脂肪酸效用系数大小依次为:ARA>EPA>DHA>C18:3>0>C16:1>C18:2>C18:1,对ARA抗氧化效用最大,效用系数达到10.193%,C20:5为0.490%,C22:6为0.364%;维生素E醋酸酯对饱和脂肪酸效用系数大小依次为:C14>C17>0>C18>C16。  相似文献   

12.
1INTRODUCTIONInrecentyearsglobalclimatechangehasbeenanissueofbothpublicandscientificconcern.Oceanscover71 %ofearthandplayamajorroleinglobalclimatechange.Phosphorus,asacriticalelement,regulatespri maryproductioninaquaticecosystems.Therefore,thefunctionofphosphorusinoceansystemhasreceivedin creasingscientificinterest(Songetal.,2 0 0 3 ) .PP (particulatephosphorus)isanimportantforminphosphorustransferinseawater(Song,2 0 0 1 ) .Pro portionofPPintotalphosphorus(TP)inseawatervar iesfrom 1 0 …  相似文献   

13.
IAA 3-Indolylacetic acid, NAA a-Naphthylacetic acid and cytokinins in PESI culture medium were used in a study on the effects of plant hormones on the growth of free-living conchocelis ofPorphyra yezoensis which showed that its growth in medium with cytokinins, IAA and NAA was more rapid than that in medium with non—phytohormones; that the optimal concentrations for promoting growth were 10 μg/L for IAA and ZA (Zeatin), and 0.1 μg/L for BA 6-Benzyl amino purine and KIN 6-Furfurylamino- purine. Mix use of NAA, IAA and cytokinins, NAA/ZA 1–1000/1 μg/L, NAA/BA 10/1-1000 μg/L, NAA/KIN 1/1-1000 μg/L promoted growth. IAA/ZA 0.1-1/0.1-1 μg/L; IAA/BA 0.1-1/0.1-10 μg/L IAA/KIN 1/0.1-1000 μg/L also promoted growth. Contribution No. 2335 from the Institute of Oceanology, Chinese Academy of Sciences. Contribution No. 94 from the Experimental Marine Biology Lab Qingdao, China. The research was supported by a grant from the Chinese Academy of Sciences.  相似文献   

14.
通过对高效液相色谱法(HPLC)测定水产饲料中三聚氰胺含量的方法进行优化,得到最佳色谱条件和前处理方法,建立了水产饲料中三聚氰胺的检测方法。结果表明:以体积比8∶92的乙腈、庚烷磺酸钠离子对试剂为流动相,柱温40℃,流速1.2 mL/min,以波长236 nm检测;以提取液为18 mL50%(φ)乙腈水+1 mL乙酸锌+1 mL1mol/L盐酸,淋洗液3 mL水和3 mL甲醇,洗脱体积6 mL作样品前处理。三聚氰胺加标回收率为85%~100%,相对标准偏差(RSD)小于5%,线性范围为0.2 mg/L~5.0mg/L,相关系数0.999 8,方法检出限为0.2 mg/kg。  相似文献   

15.
Caulerpa lentillifera is a green algae that distributes worldwide and is cultivated for food. We assessed vegetative propagation of C. lentillifera by measuring the specific growth rate(SGR) and chlorophyll fluorescence of the green algae cultured at different salinities and nutrient levels. The results indicated that C. lentillifera can survive in salinities ranging from 20 to 50,and can develop at salinities of 30 to 40. The maximum SGR for C. lentillifera occurred at a salinity of 35. Both chlorophyll content and the ratio of variable to maximum fluorescence( Fv / Fm) were also at a maximum at a salinity of 35. Photosynthesis was inhibited in salinities greater than 45 and less than 25. Both the maximum SGR and maximum chlorophyll content were found in algae treated with a concentration of 0.5 mmol/L of NO3-N and 0.1 mmol/L of PO 4-P. The photosynthetic capacity of photosystem II(PSII) was inhibited in cultures of C. lentillifera at high nutrient levels. This occurred when NO3-N concentrations were greater than 1.0 mmol/L and when PO4- P concentrations were at 0.4 mmol/L. As there is strong need for large-scale cultivation of C. lentillifera,these data contribute important information to ensure optimal results.  相似文献   

16.
We developed an HPLC method for analysis of the monosaccharide composition of fucoidans.The fucoidan was hydrolyzed into monosaccharides with 2 mol/L trifluoroacetic acid.Using ribose as the internal standard,the monosaccharide derivatives,obtained with 1-Phenyl-3-methyl-5-pyrazolone(PMP),were separated by reverse-phase HPLC using a gradient elution process,and monitored by ultraviolet detection at 245 nm.In the concentration range of 0.1-2.0 mmol/L,the peak area of each monosaccharide had a good linear rel...  相似文献   

17.
1 Introduction Nannochloropsissp .areoneofpotentialsourcesofpolyunsaturatedfattyacids ,especiallytheeicosapen taentaenoicacid (EPA ,C2 0∶5 ) ,whichisimportantforbothanimalsandhumans . Thefattyacidcompositionofthisalgaisaffectedbyvariousenvironmentalfactors ,suchaslightintensity(Sukeniketal.,1989;Sukeniketal.,1990 ) ,imply ingthatafactorinfluencingthephotosyntheticprocessmayaffectcellularfattyacidsynthesisandtheirmetabolism .AselectionprogramofincreasingcellularEPAcontenthasbeencarriedo…  相似文献   

18.
对长江下游凤鲚、湖鲚和刀鲚卵巢氨基酸、脂肪酸和矿物元素组成及含量进行了测定分析。结果表明:三种鲚属鱼类卵巢鲜样中总氨基酸、必需氨基酸、呈味氨基酸含量差异不显著;必需氨基酸含量(w)为5.36%~6.32%,占总氨基酸含量为:0.43%、0.41%和0.43%,均以亮氨酸含量最高而色氨酸最低,赖氨酸含量(w)为0.96%~1.04%;饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸差异较显著,脂肪酸组成均以油酸含量最高,EPA和DHA总量(w)为8.00%~11.81%;矿物质含量大多也存在显著差异,常量元素含量最高的为钾(16970~22220mg/kg),微量元素则为锌(262.0~277.0mg/kg);不同水域生长环境对鲚属鱼类卵巢氨基酸含量影响不显著,而对脂肪酸和矿物质含量影响较显著。  相似文献   

19.
长江下游江段铜鱼肌肉营养成分分析   总被引:7,自引:0,他引:7  
对采自长江下游江段的铜鱼(Coreius heterodom)肌肉营养成分进行了测定和分析。结果表明,铜鱼肌肉水分、粗蛋白质、粗脂肪和粗灰分占鲜样的比例分别为:70.03%、20.54%、6.82%和1.38%;按照氨基酸评分(Amino Acid Score,AAS)和化学评分(Chemical Score,CS)标准,铜鱼限制性氨基酸为缬氨酸和异亮氨酸,必需氨基酸指数(EAAI)为81.52;不饱和脂肪酸和ω-3多不饱和脂肪酸含量分别为63.03%和2.0%;肌肉中常、微量元素含量最高分别为钾(3135μg/g)和铁(5.46μg/g),锌铜比和锌铁比分别为8.85和0.65。  相似文献   

20.
The effect of Mg2+, NaCl and citric acid on the accumulation of β-carotene inDunaliella Salina was studied. The experimental results showed that 10.5 mmol/L Mg2+, 5 mol/L NaCl, 3 μmol/L citric acid, and CO2 are favorable forDunaliella Salina cell growth and β-carotene accumulation. After 144 h culture under the above conditions, theDunaliella Salina biomass increased by 7.18 times; β-carotene reached 9.61%. Project 89023990 supported by the Shandong Natural Science Fund.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号