Heart Healthy Microalgae? Algal production of TAGs with high levels of PUFAs

描述（由申请人提供）：美国心脏协会和欧洲心脏病学会建议多不饱和脂肪酸（PUFA）的饮食摄入量为1 g/d，以预防冠心病。PUFA的人类膳食来源主要来自鱼和鱼油。不幸的是，这些天然来源可能会受到毒素的生物累积的影响;此外，衍生油中的脂肪酸（FA）组成 并不一致，可能并不总是高PUFA。令人遗憾的是，仅凭野生渔业的下降，无法满足不断增长的人口对饮食的需求。微藻是包括脂肪酸在内的多种有益代谢物的来源。它们能够合成和积累PUFA，为膳食需求提供替代来源。已知产油微藻具有不同的脂质生产率，并且可以积累高达约67%的脂质（以干重计）。富含PUFA的微藻的培养是膳食omega-3 FA的潜在来源。在目标1中，我们确定环境条件对PUFA合成和初级代谢物库的影响。我们将对产油微藻N.盐藻在低温胁迫和营养胁迫下生长。微藻对不同环境条件的适应性不仅直接影响微藻的生长和产量，而且对脂质的产生和组成具有决定性作用。在目标2中，我们将使用FT-ICR MS通过详细的组成分析来确定完整的脂质组。这些结果将鉴定富含PUFA侧链的脂质类。我们还将确定脂质类和代谢池如何受到非生物环境胁迫的影响和重塑，促进被隔离成三酰甘油（TAG）合成和积累的PUFA的合成。在这个试点提案的结论，我们将有新的信息的作用，非生物胁迫对总PUFA积累和代谢重新分配，支持碳通量向他们的合成。其次，我们确定了其他脂质物质在重塑和提供高度不饱和脂肪酸以支持富含PUFA的TAG从头合成中的作用。藻类种植非常适合西南沙漠，特别是海藻，它可以利用非耕地和咸水层。富含PUFA的微藻的培养是膳食ω-3脂肪酸的潜在来源，其可以广泛且经济地用于预防美国西南部基于营养的健康差异。

DESCRIPTION (provided by applicant): The American Heart association and the European Society of Cardiology recommend a dietary consumption of polyunsaturated fatty acids (PUFAs) at 1 g/d for the prevention of coronary heart disease. Human dietary sources of PUFAs are mainly derived from fish and fish oil. Unfortunately these natural sources may be compromised with the bioaccumulation of toxins; further the composition of fatty acids (FAs) in the derived oil are not consistent and may not always be high in PUFAs. Sadly declining wild fisheries alone will not fulfill the demand for the dietary requirements from a growing human population. Microalgae are sources of a variety of beneficial metabolites including FAs. They are capable of synthesizing and accumulating PUFAs providing an alternate source for dietary requirements. Oleaginous microalgae are known for their varying lipid productivity and can accumulate up to ~67% lipid by dry wt. Cultivation of microalgae rich in PUFAs is a potential source of dietary omega-3 FAs. In Aim 1 we determine the effect of environmental conditions on PUFA synthesis and primary metabolite pools. We will quantify the abundance and specific FA composition of lipid produced by the oleaginous microalgae N. salina when grown under cold stress & nutrient stress. Adaptability of microalgae to varying environmental conditions does not only directly affect growth and yield but has a determining role on lipid production and composition. In Aim 2 we will determine the complete lipidome by a detailed compositional analysis using FT-ICR MS. These results will identify lipid classes enriched in PUFAs side chains. We will also determine how lipid classes and metabolic pools are influenced and remodeled by abiotic environmental stress promoting the synthesis of PUFAs that are sequestered into triacylglycerol (TAG) synthesis and accumulation. At the conclusion of this pilot proposal, we will have new information on the roles of abiotic stress on total PUFA accumulation and the metabolic reallocation that supports carbon flux towards their synthesis. Secondly we identify the role that other lipid species play in remodeling and providing highly unsaturated FAs to support the de novo synthesis of TAG rich in PUFA. Algae cultivation is well suited to the desert southwest, especially marine algae, which can use the non-arable land and saline aquifers. The cultivation of microalgae rich in PUFAs is a potential source of dietary omega-3 FAs which can be broadly and economically available for the prevention of nutritionally-based health disparities in the southwestern United States.