Optimising strain selection and developing a biorefinery for industrially relevant micro-algae

本提案的主要目标是通过采用不同的藻类生物炼制方法来提高商业规模藻类生物技术的潜力。候选物种将根据其生化特征和细胞特征，培养难易程度和商业化潜力进行选择。例如，小球藻（Chlorella spp.）、纳米绿藻（Nannochloropsis spp.）、褐指藻（Phaeodactylum sp.）和组织藻（Tisochyrsis sp.）都能够合成一系列色素、类胡萝卜素和必需脂肪酸，这使得它们在营养、制药和水产养殖饲料行业具有潜在的价值。此外，它们都有不同的细胞形态，这使它们对下游加工的抵抗程度不同。为了从所生产的生物质中获得最高价值，将研究各种细胞破坏（冷冻/解冻、磨粒、超声）和产品纯化（过滤、离心、色谱）技术。然后可以在大型光生物反应器中进行可行性研究，以便更好地概述工业微藻生物技术的商业潜力。另一个棘手的问题是缺乏针对被开发的微藻种类量身定制的培养基和条件。这可能对所生产的生物质的质量和数量产生重大影响。为了解决这些问题，学生将与学术合作伙伴SAMS （UHI）和工业合作伙伴Xanthella密切合作，因为两个组织都在同一地点，这将进一步促进与生产方法/规模和正在进行的生物炼制方法有关的反馈。a.最初的候选微藻物种将根据专业知识、适用性/最终用途、市场性和立法（即GRAS认证）进行选择（第0-3个月）。b.将开发和优化一套方法，这些方法将在整个学习期间用于评估藻类的生长（血细胞计/光密度/库尔特计数器）和藻类生物量的生化成分（分光光度法/高效液相色谱法/气相色谱-质谱法）。每个候选物种的最佳生长条件将使用高通量筛选方法（多孔板阅读器）确定。(月0-18)。c.将测试培养条件（例如使用CT室的培养基配方、盐度、光照和温度制度、Algem环境建模PBR和Xanthella的PBR以及选择性育种），以修改细胞特性，以减轻细胞破坏并提高产品产量（第6-24个月）。最有希望的候选物种将使用microPharos和Pandora光生物反应器（PBRs）进行更大规模的培养，与生物炼制框架保持一致，这将在Xanthella Ltd场所完成（18-36月）。e.使用各种技术（如冻融/磨粒/超声波）将破坏藻类生物量。将使用直接和间接方法（细胞计数/生物化学/显微镜/流式细胞术结合人工辅助机器学习）评估破坏效率。将努力在细胞破坏步骤中实现选择性释放，以促进进一步的分离步骤。为此，由于特定成分位于不同的细胞区室或细胞器上，因此需要了解细胞拓扑结构，以设计利用这种区室化的选择性释放策略（第6-36个月）。将根据不同的物种探索不同的生物炼制策略。战略将建立在管理团队以前的经验基础上，并将考虑目标产品的兴趣、可提取性和技术经济分析（第6-36个月）。监督小组：Michele Stanley教授、Sebastien Jubeau博士、Valeria Montalescot博士和Michael Ross博士

Grant: BB/T50872X/1 BBRSCThe main objective of this proposal is to improve the potential for commercial-scale algal biotechnology by employing different algal biorefinery approaches. Candidate species will be selected based upon their biochemical profile and cellular characteristics, ease of cultivation, and commercialisation potential. For example, Chlorella spp., Nannochloropsis spp., Phaeodactylum sp. and Tisochyrsis sp. are all capable of synthesising an array of pigments, carotenoids and essential fatty acids that make them potentially valuable for nutrition, pharmaceutical and aquaculture feed industries. Furthermore, they all have different cell morphologies which give them varying degrees of recalcitrance to downstream processing. In order to obtain the highest value from the biomass produced, a variety of cell disruption (freeze/thawing, bead milling, sonication) and product purification (filtration, centrifugation, chromatography) techniques will be investigated. Feasibility studies can then be performed in large-scale photobioreactors to give a better overview of the commercial potential of industrial micro-algal biotechnology. Another sticking point is the lack of tailoring culture of media and conditions to the microalgal specie being exploited. This can have a major impact in terms of the quality and quantity of biomass produced. In order to address these issues the student will work closely with both the academic partner, SAMS (UHI), and the industrial partner, Xanthella, since both organisations are on the same site this will further facilitate feedback in relation to the production methods/scale and biorefinery approaches being undertaken. Specifically we will: The project a. Initially candidate micro-algal species will be selected based upon expertise, applicability/end-use, and marketability and legislature (i.e. GRAS certified)(Month 0-3). b. A suite of methods will be developed and optimised that will be used throughout the studentship to assess growth (haemocytometer/optical density/Coulter counter) and the biochemical composition of the algal biomass (spectrophotometry/HPLC/GC-MS). Optimal growing conditions for each candidate species will be determined using a high-throughput screening approach (multi-well plate reader). (Month 0-18). c. Cultivation conditions (e.g. media formulation, salinity, light and temperature regime using CT rooms, Algem environmental modelling PBR's and Xanthella's PBRs, and selective breeding) will be tested to amend cellular properties with a view to ease cell disruption and enhance product yield (Month 6-24). d.Reward The most promising candidate specie(s) will be cultivated at a larger-scale, using the microPharos and Pandora photobioreactors (PBRs), in alignment with the biorefinery framework this will completed at Xanthella Ltd premises (Month 18-36). e. Algal biomass will be disrupted using a variety of techniques (e.g. freeze-thaw/bead milling/sonication). Disruption efficiency will be assessed using both direct and indirect methods (cell counts/biochemistry/microscopy/flow cytometry coupled with human-assisted machine learning). Efforts will be made to achieve selective release during the cell destruction step to facilitate further fractionation steps. For this purpose, as specific components are located on different cell compartments or organelles, the understanding of cellular topology is required to design a selective release strategy that take advantage of this compartmentalisation (Month 6-36). f.Reward Different biorefinery strategies will be explored on a species-by-species basis. Strategies will be founded upon the previous experiences of the supervisory team and will take into account target product(s) of interest, extractability, and techno-economic analysis (Month 6-36). Supervisory Team: Professor Michele Stanley, Dr Sebastien Jubeau, Dr Valeria Montalescot and Dr Michael Ross