SBIR Phase I: Microbial conversion of pectin-rich agricultural waste into specialty chemicals

这个小型企业创新研究(SBIR)项目的更广泛影响/商业潜力是酵母发酵技术的开发，该技术能够将富含果胶的农业废弃物中丰富的糖类转化为有用的特种化学品。美国是富含果胶的农业废弃物的主要生产国，包括柑橘皮(每年500万吨)、甜菜(每年3700万吨)和葡萄渣(每年100万吨)。这些果皮和纸浆副产品缺乏价值，然而，该项目中开发的拟议技术将允许从这些废流中生产出更高价值的产品。最初的目标化学产品用作清洁产品的螯合剂和塑料的前体。其他化工产品可能会使用该平台生产。与石油甚至其他糖类产品相比，这种发酵过程的碳足迹和排放量更低，并对减少浪费和应对气候变化产生了影响。当大规模实施时，这些发酵加工厂将与农村农业加工厂共处一地，在这些领域增加高科技工作岗位，并提供一种手段，通过进入替代市场来降低历史上不稳定的作物收成的风险。这个SBIR第一阶段项目提议设计能够将富含果胶的农业废物中的糖转化为有价值的特种化学品的酵母菌株。目前，利用果胶中的主糖D-半乳糖醛酸的发酵速度限制了这些化学物质的生产，包括拟议的第一个产品，这是一种可生物降解的金属螯合剂。先前的研究表明，转运蛋白对果胶糖的摄取是限制步骤。因此，这项提案的第一个目标是描述这类运输商的特征，以确定费率提高的新运输商。第二个目标是通过蛋白质工程改善最好的转运蛋白。使用这种改进的传送器，最终目标将评估发酵过程中的细胞能量需求，使用生物反应器来控制发酵罐条件，因为产品的合成和运输需要大量能源。如果成功，该项目将能够从富含果胶的农业废物中生产特种化学品。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The broader impact/commercial potential of this Small Business Innovation Research (SBIR) project is the development of yeast fermentation technologies that enable conversion of sugars abundant in pectin-rich agricultural waste into useful specialty chemicals. The U.S. is a leading producer of pectin-rich agricultural wastes including citrus peels (5 million tons annually), sugar beets (37 million tons annually), and grape pomace (1 million tons annually). These peel and pulp byproducts lack value, however, the proposed technologies developed in this project will allow for significantly higher valued products to be produced from these waste streams. The initial target chemical product is used as a chelator in cleaning products and a precursor to plastics. Other chemical products potentially may be produced using this platform. Implementation of this fermentation process offers a lower carbon footprint and emissions compared to petroleum or even other sugar-derived products, and has impact in reducing waste and combating climate change. When implemented at scale, these fermentation processing plants will be co-located with rural agricultural processing plants, adding high-tech jobs in these areas, and offering a means to de-risk historically volatile crop harvests by accessing alternative markets.This SBIR Phase I project proposes to engineer yeast strains capable of converting sugars in pectin-rich agricultural wastes into valuable specialty chemicals. Currently, the fermentation rates for utilizing the primary sugar in pectin, D-galacturonic acid, limits production of these chemicals, including the proposed first product, which is a biodegradable metal chelator. Previous characterization has identified that uptake of the pectin sugars by a transporter as the limiting step. Accordingly, the first objective of this proposal is to characterize this class of transporter to identify new transporters with improved rates. The second objective is to improve the best transporter through protein engineering. Using this improved transporter, the final objective will assess the cellular energy requirements for the fermentation process using bioreactors to control fermenter conditions, as product synthesis and transport is energy-demanding. If successful, this project will enable production of specialty chemicals from pectin-rich agricultural waste.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.