固定化培养中氮磷浓度对钝顶螺旋藻生长及其代谢产物和叶绿素荧光参数的影响  

Effect of Nitrogen and Phosphorous Concentrations on Growth,Metabolites and Chlorophyll Fluorescence Parameters of Immobilized Spirulina platensis

作　　者：崔岩 刘海燕 李武阳 王丽娟[1] 罗光宏[1] CUI Yan;LIU Haiyan;LI Wuyang;WANG Lijuan;LUO Guanghong(Hexi University,Gansu Microalgae Technology Innovation Center,Zhangye,Gansu 734000,China;College of Biological and Pharmaceutical Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)

机构地区：[1]河西学院,甘肃省微藻技术创新中心,甘肃省河西走廊特色资源利用重点实验室,甘肃张掖734000 [2]兰州交通大学生物与制药工程学院,兰州730070

出　　处：《西北植物学报》2023年第1期136-146,共11页Acta Botanica Boreali-Occidentalia Sinica

基　　金：甘肃省科技计划(20JR5RA196);河西学院校长基金(XZZD2018002);甘肃省高等学校创新基金(2020B-213,2021QB-112);甘肃省高等学校产业支撑项目(2020C-25);创新基地和人才项目(甘科技[2021]12号)。

摘　　要：该研究以钝顶螺旋藻为实验对象,探究培养基中不同氮浓度(5、15、30、45 mmol·L^(-1))和磷浓度(0.5、1.5、3.0、4.5 mmol·L^(-1))对固定化生物膜培养模式下螺旋藻生长及其代谢产物和叶绿素荧光参数的影响,为生产实际中规模化高效培养螺旋藻提供理论依据。结果表明:(1)随着氮、磷浓度的升高,螺旋藻的生物量密度和产率先增高后降低,并在30 mmol·L^(-1)氮和3.0 mmol·L^(-1)磷处理时达到最大值;低氮、低磷条件会影响螺旋藻的藻体结构,表现为单细胞藻丝变短,螺旋变少,导致生物膜细胞密度降低。(2)与生物量变化趋势一致,螺旋藻光合色素含量随着培养基中氮、磷浓度的增加呈先升后降的变化趋势,且均在30 mmol·L^(-1)氮或者3.0 mmol·L^(-1)磷条件下达到最大值。(3)培养基中磷浓度固定时,螺旋藻的PSⅡ反应中心最大光能转化效率(F v/F m)和电子传递速率(ETR)随着氮浓度增加而增大,氮的缺乏会影响光合色素的合成,进而削弱螺旋藻光合作用;培养基中氮浓度固定时,螺旋藻的F v/F m和ETR随着磷浓度的增加呈现先升后降的趋势。(4)低氮、低磷条件下虽不利于可溶性蛋白的增加,却可以刺激可溶性多糖的积累,并且磷源限制程度越严重,螺旋藻蛋白质含量越低,多糖含量越高。研究认为,调节营养液中氮、磷浓度可定向诱导螺旋藻蛋白和多糖等高值化产物的合成,生产中可通过调控氮、磷浓度来促进相应目标产物的合成积累;螺旋藻生物膜对氮浓度的耐受程度较磷浓度更强,螺旋藻叶绿素荧光参数在高氮(45 mmol·L^(-1))培养下均较高,同时生物质产量也较高。This study took Spirulina platensis as the experimental object to explore the effects of nitrogen concentrations(5,15,30 and 45 mmol·L^(-1))and phosphorus concentrations(0.5,1.5,3.0 and 4.5 mmol·L^(-1))on the growth,metabolites and chlorophyll fluorescence parameters of immobilized S.platensis,so as to provide a theoretical basis for large-scale and efficient cultivation of Spirulina.Results showed that:(1)with the increase of nitrogen and phosphorus concentrations in the culture medium,the biomass density and productivity of S.platensis increased first and then decreased,and reached their highest values at the nitrogen concentration of 30 mmol·L^(-1)and phosphorus concentration of 3.0 mmol·L^(-1).Low nitrogen and phosphorus concentrations affected the cellular structure of S.platensis,manifested as shorter single-cell filaments and fewer spirals,leading to the decrease of biofilm cell density.(2)Consistent with the S.platensis biomass,the content of photosynthetic pigments showed a trend of first increasing and then decreasing with the increase of nitrogen and phosphorus concentrations in the medium,and both reached the highest values at nitrogen concentration of 30 mmol·L^(-1)or phosphorus concentration of 3.0 mmol·L^(-1).(3)When the phosphorus concentration in the medium was fixed,the maximum light energy conversion efficiency(F_(v)/F_(m))and electron transfer rate(ETR)of the PSⅡreaction center of S.platensis increased with the increase of nitrogen concentration,and the lack of nitrogen affected the photosynthetic pigments synthesis,thereby weakening the photosynthesis of S.platensis.When the nitrogen concentration in the medium was fixed,the F_(v)/F_(m)and ETR of S.platensis showed a trend of first increasing and then decreasing with the increase of phosphorus concentration.(4)Although low nitrogen and phosphorus concentrations were not conducive to the increase of soluble proteins,they could stimulate the accumulation of soluble polysaccharides,and the more severe the limitation of phosphorus source

关 键 词：钝顶螺旋藻 氮磷浓度 生物量 光合色素 叶绿素荧光 蛋白质 多糖 

分 类 号：Q946.8[生物学—植物学] S188[农业科学—农业基础科学] S555.6