发酵盐浓度对Chlorella vulgaris生物合成蛋白与油脂的影响

Effect of Salinity in fermentation medium on Chlorella vulgaris protein and lipid contents

实验室条件下,考察了发酵过程中不同盐度对小球藻细胞生长、蛋白及油脂含量的影响,结果表明:培养时间为144h,小球藻在无NaCl培养基中生长最佳,其细胞干重、光合色素含量、比生长速率和最大生产强度分别为0.750g·L-1、39.50mg·g-1、0.225d-1和0.125g·L-1·d-1,且氮磷利用率高分别为96.4%及93.5%,其消耗效率分别为9.10、0.71mg·L-1·d-1,藻蛋白含量也最高为55.0%(W),其生产效率为68.40mg·L-1·d-1;而藻细胞培养在2.5%NaCl浓度下,在96h脯氨酸含量达最高为2.25%(W),最高与最低值之比超过20.0;小球藻培养在含2.5%NaCl培养基中,在144h油脂含量最高达15.5%(W),其生产效率为16.10mg·L-1·d-1。NaCl浓度不仅影响小球藻细胞对氮磷等营养的吸收,而且对生物量、蛋白质、脯氨酸及油脂等细胞组分的生物合成具有明显影响。藉此,提出了通过改变盐浓度,达到调控小球藻胞内生理代谢组分的可行性。

Salinity-inducing effect on growth,metabolism of protein and lipid of Chlorella vulgaris were studied. In laboratory conditions,culture time of 144h lasted,the algal growth was the best under 0.0% NaCI ,in which its biomass, chlorophyll, specific growth rate and productivity were 0.750g · L-1 , 39.50mg · g-1,0.225d-1 and 0.125g· L-1. d-1, respectively, decreased significantly in higher 3.5% NaCI salinity. Additionally,the consumptions of nitrogen（N） and phosphorus（P） were 96.4% and 93.5%,with productivities of 9.10 and 0.71mg.L-1.d-1, respectively. The algal protein was significantly higher in non-salinity with a final content of around 55.0% （W） from the dry biomass and a productivity of 68,40mg. L-1. d-1, At the 96h, proline were higher in mezzo-salinities （2.5%） with the final contents of around 2.25%（W）,and the ratios of the highest （2.5% salinity） to the lowest value（0.0% salinity） was around 20.0. Similarly,at the 144h,lipid was higher in mezzo-salinities（2.5%） with the final contents of around 15.5%（W） and a productivity of 16.10mg.L-1.d-l,which the ratios of the highest（2.5% salinity） to the lowest value（0.0% salinity） was around 3.6. Under hypo- and hyper-salinity treatments,both proline and lipid were lower. These results collectively suggested that NaCI salinity couldn＇t only affect some nutrient consumption of nitrogen and phosphorus significantly,but also the algal biomass and components of protein, amino acid and lipid. Therefore ,salinity could be modified to regulate physiological compositions of the algal cell during the cultivation of Chlorella vulgaris.