采用流式细胞仪检测细胞增长与色素含量、原子火焰吸收光谱法测定金属含量以及显微镜观察细胞状态等方法研究了红树林底栖硅藻新月筒柱藻(Cylindrotheca closterium(Ehr.)Re im ann and Lew in)暴露在重金属锌96 h内的细胞增长、光合色...采用流式细胞仪检测细胞增长与色素含量、原子火焰吸收光谱法测定金属含量以及显微镜观察细胞状态等方法研究了红树林底栖硅藻新月筒柱藻(Cylindrotheca closterium(Ehr.)Re im ann and Lew in)暴露在重金属锌96 h内的细胞增长、光合色素含量和细胞形态结构等胁迫效应,以及锌在藻细胞内外动态分布的情况.结果为:(1)在Zn2+浓度小于10mg/L范围内,锌对新月筒柱藻的细胞增长和色素含量均无显著抑制作用.(2)1 mg/L和10 mg/L的Zn2+对藻细胞内的叶黄素和叶绿素a的产生都有促进作用.(3)在实验开始的24 h内,藻细胞处在低Zn2+浓度(1 mg/L)时,藻细胞胞内吸收的Zn2+大于胞外吸附的Zn2+.而藻细胞处在高Zn2+浓度(10 mg/L)时,胞外吸附的Zn2+较胞内吸收的大,细胞内Zn2+的含量处在较低水平,从而促进细胞的增长和色素的合成并使细胞免受外界高浓度锌的毒害.可见,新月筒柱藻正是通过改变对锌的富集方式,以保持细胞内锌含量的相对稳定来适应不同浓度锌的胁迫.展开更多
Four strains of Cylindrotheca (B156, B164, B196, and B200) were harvested at three phases in the growth curve and their total lipid and fatty acid composition were determined. Total lipid reached highest values in the...Four strains of Cylindrotheca (B156, B164, B196, and B200) were harvested at three phases in the growth curve and their total lipid and fatty acid composition were determined. Total lipid reached highest values in the late stationary phase in B156 (24.0%), B164 (26.6%) and B200 (17.3%), in the exponential phase in B196 (15.5%). Saturated fatty acids increased with the development of the culture in B156 and B196, and reached their highest values in the late stationary phase in B156 (41.7%) and B196 (45.1%), in the early stationary phase in B164 (45.4%) and B200 (37.6%). Monounsaturated fatty acids increased with the development of the culture in B196 and B200, and reached their highest values in the late stationary phase in B196 (32.4%) and B200 (32.8%), in the early stationary phase in B164 (31.0%) and in the exponential phase in B156 (29.3%). Polyunsaturated fatty acids decreased in the later phases of the culture in B164, B196 and B200, and peaked in the exponential phase in B164 (29.5%), B196 (42.9%) and B200 (37.3%), and in the early stationary phase in B156 (32.0%).展开更多
A diatom was purified with colony selection and continuous dilution methods. It was identified to Cylindrotheca closterium according to its morphological characteristics and rbc L and 18 s r RNA gene sequences. The al...A diatom was purified with colony selection and continuous dilution methods. It was identified to Cylindrotheca closterium according to its morphological characteristics and rbc L and 18 s r RNA gene sequences. The alga was not sensitive to ampicillin and neomycin, but sensitive to chloramphenicol which inhibited its growth at concentrations ranging from 50 to 150 μg m L-1. The purified alga was easy to culture and its specific growth rate was 0.207 ± 0.002(d-1). It was resistant to pollution and could be harvested in an easy way. It was relatively high in lipid content(20.08% ± 0.67% of dry weight) and the combined amount of its 16:0 and 16:1(n-7), the most suitable resource of biodiesel, was as high as 64% of the total fatty acids, while the amount of polyunsaturated fatty acids reached 19.96%–20% of the total fatty acids. Thus the purified C. closterium can be cultured as a biodiesel producer or a nutrition supplement producer.展开更多
文摘采用流式细胞仪检测细胞增长与色素含量、原子火焰吸收光谱法测定金属含量以及显微镜观察细胞状态等方法研究了红树林底栖硅藻新月筒柱藻(Cylindrotheca closterium(Ehr.)Re im ann and Lew in)暴露在重金属锌96 h内的细胞增长、光合色素含量和细胞形态结构等胁迫效应,以及锌在藻细胞内外动态分布的情况.结果为:(1)在Zn2+浓度小于10mg/L范围内,锌对新月筒柱藻的细胞增长和色素含量均无显著抑制作用.(2)1 mg/L和10 mg/L的Zn2+对藻细胞内的叶黄素和叶绿素a的产生都有促进作用.(3)在实验开始的24 h内,藻细胞处在低Zn2+浓度(1 mg/L)时,藻细胞胞内吸收的Zn2+大于胞外吸附的Zn2+.而藻细胞处在高Zn2+浓度(10 mg/L)时,胞外吸附的Zn2+较胞内吸收的大,细胞内Zn2+的含量处在较低水平,从而促进细胞的增长和色素的合成并使细胞免受外界高浓度锌的毒害.可见,新月筒柱藻正是通过改变对锌的富集方式,以保持细胞内锌含量的相对稳定来适应不同浓度锌的胁迫.
文摘Four strains of Cylindrotheca (B156, B164, B196, and B200) were harvested at three phases in the growth curve and their total lipid and fatty acid composition were determined. Total lipid reached highest values in the late stationary phase in B156 (24.0%), B164 (26.6%) and B200 (17.3%), in the exponential phase in B196 (15.5%). Saturated fatty acids increased with the development of the culture in B156 and B196, and reached their highest values in the late stationary phase in B156 (41.7%) and B196 (45.1%), in the early stationary phase in B164 (45.4%) and B200 (37.6%). Monounsaturated fatty acids increased with the development of the culture in B196 and B200, and reached their highest values in the late stationary phase in B196 (32.4%) and B200 (32.8%), in the early stationary phase in B164 (31.0%) and in the exponential phase in B156 (29.3%). Polyunsaturated fatty acids decreased in the later phases of the culture in B164, B196 and B200, and peaked in the exponential phase in B164 (29.5%), B196 (42.9%) and B200 (37.3%), and in the early stationary phase in B156 (32.0%).
基金supported by the Major State Basic Research Development Program of China (973 Program) (2011CB200901)National Technical Supporting Project Foundation (2011BAD14B01)Energy Project from State Bureau of Oceanic Administration (Grant No. GHME2011SW03)
文摘A diatom was purified with colony selection and continuous dilution methods. It was identified to Cylindrotheca closterium according to its morphological characteristics and rbc L and 18 s r RNA gene sequences. The alga was not sensitive to ampicillin and neomycin, but sensitive to chloramphenicol which inhibited its growth at concentrations ranging from 50 to 150 μg m L-1. The purified alga was easy to culture and its specific growth rate was 0.207 ± 0.002(d-1). It was resistant to pollution and could be harvested in an easy way. It was relatively high in lipid content(20.08% ± 0.67% of dry weight) and the combined amount of its 16:0 and 16:1(n-7), the most suitable resource of biodiesel, was as high as 64% of the total fatty acids, while the amount of polyunsaturated fatty acids reached 19.96%–20% of the total fatty acids. Thus the purified C. closterium can be cultured as a biodiesel producer or a nutrition supplement producer.
