Guevara Miguel, Lodeiros César, Gómez Olga, Lemus Nathalie, Núñez Paulino, Romero Lolymar, Vásquez Aléikar, Rosales Néstor
Laboratorio de Acuicultura, extensión Plancton, Dpto. Biología Pesquera, Instituto Oceanográfico de Venezuela, Universidad de Oriente, Cumaná 6101, Venezuela.
Rev Biol Trop. 2005 Sep-Dec;53(3-4):331-7.
We evaluated discontinuous cultures (Algal medium at 0.5 mM of NaNO3, and 27% NaCI) of five strains of Dunaliella sp. isolated from Venezuelan hypersaline lagoons (Araya, Coche, Peonia, Cumaraguas. and Boca Chica) and one strain from a reference collection (Dunaliella salina, LB1644). Cultures were maintained to 25+/-1 degrees C, with constant aeration, photoperiod 12:12, and two light intensities (195 and 390 microE.m(-2).s(-1)) during 30 days. Cell count was recorded on a daily basis using a Neubaüer camera. Totals of chlorophyll a and carotenoids were measured at the end of the experiment. The largest cellular densities were measured during the smallest light intensities. The strain with the largest cellular density was isolated from Boca Chica (8 xl0(6) and 2.5 xl0(6) cel.ml(-1) a 390 and 195microE.m(-2).s(-1), respectively). The increment of light intensity produced a significant reduction of growth rates in all strains. Totals of carotenoids by volume were as large as 390 microE.m(-2).s(-1). Strains LB 1644, from Coche and Araya were those that produced the largest amount of carotenoids (38.4; 32.8 and 21.0 microg.ml(-1), respectively). Differences total carotenoids by cell between treatments were significant. The largest concentration was 390 microE.m(-2).s(-1). The strains LB 1644 and Coche produced the highest values of carotenes (137.14 and 106.06 pg.cel(-1), respectively). Differences in the relation carotenoid:chlorophyll a between the strains at various light intensities was significant. Strains LB1644 presented the largest value of the relation carotenoids:chlorophyll a (20:1) at 195 microE.m(-2).s(-1). No significant differences were detected in the strain Coche (15:1). All the other strains showed relations lower than one. Our results suggest that the strains of Coche and Araya show potential to be used in the biotechnology of carotenoids production.
我们评估了从委内瑞拉高盐度泻湖（阿拉亚、科切、芍药、库马拉瓜斯和博卡奇卡）分离出的五株杜氏藻属菌株以及一株参考菌株（盐生杜氏藻，LB1644）在不连续培养条件下（含有0.5 mM硝酸钠和27%氯化钠的藻类培养基）的生长情况。培养条件为温度25±1摄氏度，持续通气，光周期12:12，在30天内设置两种光照强度（195和390微爱因斯坦·米-2·秒-1）。每天使用血细胞计数板记录细胞数量。实验结束时测量叶绿素a和类胡萝卜素的总量。在最小光照强度下测得最大细胞密度。细胞密度最大的菌株分离自博卡奇卡（在390和195微爱因斯坦·米-2·秒-1时分别为8×106和2.5×106个细胞·毫升-1）。光照强度的增加导致所有菌株的生长速率显著降低。类胡萝卜素的总体积在390微爱因斯坦·米-2·秒-1时最大。来自科切、阿拉亚的菌株LB1644产生的类胡萝卜素量最多（分别为38.4、32.8和21.0微克·毫升-1）。不同处理间细胞类胡萝卜素总量的差异显著。最大浓度为390微爱因斯坦·米-2·秒-1。菌株LB1644和科切产生的胡萝卜素值最高（分别为137.14和106.06皮克·细胞-1）。不同光照强度下各菌株类胡萝卜素与叶绿素a的比例差异显著。菌株LB1644在195微爱因斯坦·米-2·秒-1时类胡萝卜素与叶绿素a的比例最高（20:1）。科切菌株（15:1）未检测到显著差异。所有其他菌株的比例均低于1。我们的结果表明，科切和阿拉亚的菌株在类胡萝卜素生产生物技术中具有应用潜力。
