摘要
针对新疆地区经排碱渠排放的大量盐碱水,目前仍缺乏资源化利用,不但造成水资源浪费,也对周边土壤生态环境带来严重威胁。该研究从排碱渠水中分离得到一株产油微藻WY205,经鉴定为小球藻(Chlorella sp.),在此基础上,以排碱渠水为培养基质,考察了补充有机碳源对该藻生长及油脂积累的影响,以及微藻的盐耐受性、在半连续培养模式下该藻的生长与产油稳定性。结果表明,补充适量有机碳源可有效提高微藻生长速率和油脂产量,微藻油脂积累过程属于生长偶联型,Logistic方程和Gaden生长相关模型方程可较好地描述该藻的生长和油脂生成动力学过程,添加2.5g/L葡萄糖可获得最大生物量(3.03 g/L)和最高油脂产量(1.26 g/L),分别为不加糖处理的1.35、2.21倍。培养基中Na^(+)添加至5 g/L时(折合NaCl 12.72 g/L),微藻油脂产量比排碱渠水原液培养处理(Na^(+)浓度2.64 g/L)提高了21.69%;继续增加Na^(+)浓度至10 g/L(折合NaCl 25.43 g/L),微藻油脂产量相比排碱渠水原液处理依然提高了10.84%,说明该藻具有较高的盐耐受性。经60 d共6个周期的半连续培养,该藻生物量和油脂产量无显著(P>0.05)变化,表现出良好的适应性和稳定性。该研究表明利用排碱渠水培养产油微藻可行,可为排碱渠水的资源化利用提供技术参考。
Soil salinization is currently improved via flood irrigation and salt-washing drainage for the main crop cultivation in a typical arid desert region of Xinjiang,China.As such,most produced saline-alkali water is discharged directly through the salt-discharging channel.Loss of water resources has posed a serious threat to the local soil and ecological environment.Oleaginous microalgae offer an attractive alternative to generate biofuel in the saline-alkali land unsuitable for farming,such as desert and mudflat in recent years.However,little attention has been paid to the cultivation of oleaginous microalgae in the salt-discharging channel water with high salinity and nutrient deficiency.In this study,one species of oleaginous microalga(WY205),identified as Chlorella sp,was isolated from the salt-discharging channel water.A systematic examination was made to explore the effects of supplementation with organic carbon sources on microalgae growth and lipid accumulation.An attempt was also made to investigate the salt-tolerance,the growing and lipid producing stability of oleaginous microalga.The results showed that the addition of organic carbon sources improved significantly the growth rate and lipid yield of microalgae.Since the accumulation of microalgae lipid followed the type of growth coupling,the logistic equation and Gaden growth model were selected to describe the algal growth and kinetics of lipid generation in the salt-discharging channel water.The maximum biomass(3.03 g/L)and the highest lipid yield(1.26 g/L)were predicted at the supplementation of 2.5 g/L glucose,which were 1.35 and 2.21 times more than those treated without sugar,respectively.When the Na^(+)was added up to 5 g/L(equivalent to NaCl 12.72 g/L),the content of microalgae lipid reached 44.90%,while the lipid yield achieved the maximum,21.69%higher than that of the original water from the salt-discharging channel(Na^(+)concentration was 2.64 g/L).Even when the Na^(+)concentration enhanced to 10 g/L(equivalent to Na Cl 25.43 g/L),the content of microalgae lipid reached 59.71%,whereas,the lipid yield began to decline,10.84%higher than that of the original water from the salt-discharging channel,due to the large reduction of biomass.This indicated the high salt-tolerance of oleaginous microalgae.There was no significant change in the biomass and lipid yield of alga strain after 60 days of semi-continuous culture using undiluted salt-discharging channel water for 3 cycles plus 2 times concentrated water sample for another 3 cycles(10 days for each cycle).The content of microalgae lipid maintained higher than 30%in all cycles,exhibiting good adaptability and stability.In further optimization,the culture conditions of microalgae can be extended to the growth monitoring on a large-scale in subsequent studies.The finding can provide a promising technical reference to cultivate oleaginous microalgae for resource utilization of salt-discharging channel water.
作者
李艳宾
童旭
蒋卉
张琴
汪慧玲
Li Yanbin;Tong Xu;Jiang Hui;Zhang Qin;Wang Huiling(College of Biological and Food Engineering,Anhui Polytechnic University,Wuhu 241000,China;College of Life Science,Tarim University,Alar 843300,China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2021年第4期242-248,共7页
Transactions of the Chinese Society of Agricultural Engineering
基金
安徽省重点研究与开发计划项目(202004i07020003)
国家自然科学基金项目(21666034)
安徽工程大学中青年拔尖人才项目(S022019007)
安徽工程大学校级科研项目(Xjky04201903、2018YQQ030)。
关键词
鉴定
生长
油脂产量
排碱渠
产油微藻
identification
growth
lipid yield
salt-discharging channel
oleaginous microalgae