摘要
以I.A.M.收集的培养基Ⅱ为基本培养基,采用单因子和L16(45)正交设计法,进行了舟形藻BT001对N、P、Fe、Si四种营养盐最适需求的研究,并在此基础上,研究了尿素对正交优化组合的影响以及以尿素作为氮源对正交优化组合的影响。结果表明,N、P、Fe、Si四种营养盐最佳单因子水平为:KNO3,300mg/L;Na2HPO4·12H2O,40mg/L;FeCl3,4mg/L;Na2SiO3·9H2O,200mg/L。四种营养盐正交组合水平为:KNO3,150mg/L;Na2HPO4·12H2O,40mg/L;FeCl3,4mg/L;Na2SiO3·9H2O,200mg/L。在正交组合水平基础上,添加16mg/LCO(NH2)2,可更好的促进该藻的生长和繁殖。在8天的培养中,最大细胞相对生长率可达0.1577。在等摩尔氮源的条件下,以CO(NH2)2代替正交优化水平组合中的KNO3对舟形藻BT001进行11天的培养。结果表明,以CO(NH2)2为氮源的藻细胞最大生长密度可达2.69×105cell/ml,明显地高于硝酸钾作为氮源培养的藻细胞密度。
Marine diatom is one of the primary production contributors in marine ecosystem, and essential feeding stuff in aquiculture. The benthic species Navicula that usually contain rich polyunsaturated fatty acids are often used in the first choice to feed young seashells such as abalone. One of Navicula species, named Navicula BT001 was sampled in Yantai seashore （Shandong, China） and later isolated. This species can excrete large amount of exopolysaccharides and produce rich gamma-linoleic acid （GLA, 7.55%）, ecosapentanoic acid （EPA, 21.52%） and docosahexanoic acid （DHA, 3.64%）.
This study aimed to determine the optimal formula of four essential inorganic minerals KNO3, Na2HPO4. 12H2O, FeCl3 and Na2SiO3-9H2O for growth of Navicula BT001 in our culture. The optimal composition and concentration of the minerals were determined by single-factor test and combinational orthogonal test L16（45）. Navicula BT001 was cultured at the optimal concentration set by orthogonal test. To reduce nitrogen cost, urea was used as the substitute of KNO3. The effect on diatom growth by urea was evaluated at the optimal combinations. The results of four single-factor tests showed that the optimal concentration for KNO3 was 300mg/L, for Na2HPO4 · 12H2O at 40mg/L, FeCl3 at 4mg/L and Na2SiO3 - 9H2O at 200mg/L. In orthogonal test, the optimal concentration of the four mineral nutrients was determined at 150mg/L for KNO3, 40mg/L for Na2HPO4 · 12H2O, 4mg/L for FeCl3, and 200mg/L for Na2SiO3.9H2O. It can be seen that these results were nearly the same to those of by single-factor test, except for KNO3, whose optimal concentration was 150mg/L in orthogonal test. According to the orthogonal test result, the order of impact by the four mineral nutrients on diatom growth was Na2HPO4.12H2O 〉 Na2SiO3-9H2O 〉 KNO3 〉 FeCl3. Complete substitution of KNO3 by CO（NH2）2 in same mole concentration showed clear increase in growth rate and biomass accumulation, suggesting that urea is an ideal nitrogen source for mass maricul
出处
《海洋与湖沼》
CAS
CSCD
北大核心
2007年第2期157-162,共6页
Oceanologia Et Limnologia Sinica
基金
国家863高新技术项目
2004AA62808号
江苏省高新技术产业化项目
02KJA360002号。
