响应面法优化雨生红球藻培养基

Optimization of culture medium of Haematococcus pluvialis by response surface methodology

雨生红球藻(Haematococcus pluvialis)是生产高值天然虾青素(Astaxanthin,AST)的优质藻种,优化培养基营养盐组成对提高藻细胞密度和虾青素产量具有重要意义。以雨生红球藻为受试藻株,BG11为基础培养基,作单因素试验筛选NaNO_(3)、MgSO_(4)·7H_(2)O、K_(2)HPO_(4)·3H_(2)O和Na_(2)CO_(3)共4种营养盐最适浓度范围,采用响应面法优化培养基关键营养盐浓度,并作验证试验。结果表明,(1)雨生红球藻相对适宜营养盐NaNO_(3)、MgSO_(4)·7H_(2)O、K_(2)HPO_(4)·3H_(2)O和Na_(2)CO_(3)质量浓度范围分别为1500~2000、80~640、20~60和20~80 mg·L^(-1),对藻细胞密度的影响强弱依次为NaNO_(3)、Na_(2)CO_(3)、K_(2)HPO_(4)·3H_(2)O和MgSO_(4)·7H_(2)O;(2)通过响应面法分析得到上述四种营养盐最佳盐浓度分别为1556.42、51.43、42.18和358.59 mg·L^(-1),其中K_(2)HPO_(4)·3H_(2)O和MgSO_(4)·7H_(2)O具有显著交互作用(P<0.05);(3)使用优化后培养基培养雨生红球藻8 d后,藻细胞Fv/Fm与Chl-a浓度分别为0.69和7268.97μg·L^(-1),均极显著高于对照组(P<0.01),优化组细胞密度为3.53×10^(5)mL^(-1),较对照组显著提高20.48%(P<0.05)。

Haematococcus pluvialis is an excellent algae species for production natural astaxanthin.Optimizing the nutrients composition of the culture medium is important to improve the density of algal cells and astaxanthin content.A single-factor test was conducted to screen the optimal concentration range of NaNO_(3),MgSO_(4)·7H_(2)O,K_(2)HPO_(4)·3H_(2)O and Na_(2)CO_(3),and the medium was optimized using the response surface methodology and validation tests.The results showed as the followings:①The mass concentration of NaNO_(3),MgSO_(4)·7H_(2)O,K_(2)HPO_(4)·3H_(2)O and Na_(2)CO_(3),were in the ranges of 1500-2000,80-640,20-60 and 20-80 mg·L^(-1),respectively.The most promoting effects on algal cell density were in the order of NaNO_(3),Na_(2)CO_(3),K_(2)HPO_(4)·3H_(2)O,MgSO_(4)·7H_(2)O.②The optimal nutrient concentrations respectively were 1556.42,51.43,42.18,and 358.59 mg·L^(-1).The interaction between K_(2)HPO_(4)·3H_(2)O and MgSO_(4)·7H_(2)O was significant(P<0.05).③Cultured H.pluvialis for 8 days in the optimized medium,the Fv/Fm of PSⅡand Chl-a content of the algae cells were 0.69 and 7268.97μg·L^(-1),respectively,which were both highly significant higher than that in the control group(P<0.01),and the cell density was 3.53×10^(5)mL^(-1),which was significantly higher than the control by 20.48%(P<0.05).