Iowa State University, Ames, 50011, USA.
Appl Biochem Biotechnol. 2010 Nov;162(7):1819-33. doi: 10.1007/s12010-010-8951-y. Epub 2010 Sep 18.
The objective of this study was to evaluate the potential of low/negative value soy whey (SW) as an alternative, inexpensive fermentation substrate to culture Lactococcus lactis subsp. lactis for nisin production. Initially, a microtiter plate assay using a Bioscreen C Microbiology Plate Reader was used for rapid optimization of culture conditions. Various treatments were examined in efforts to optimize nisin production from SW, including different methods for SW sterilization, ultrasonication of soy flake slurries for possible nutrient release, comparison of diluted and undiluted SW, and supplementation of SW with nutrients. In subsequent flask-based experiments, dry bacterial mass and nisin yields obtained from SW were 2.18 g/L and 619 mg/L, respectively, as compared to 2.17 g/L and 672 mg/L from a complex medium, de Man-Rogosa-Sharpe broth. Ultrasonication of soybean flake slurries (10% solid content) in water prior to production of SW resulted in ∼2% increase in biomass yields and ∼1% decrease in nisin yields. Nutrient supplementation to SW resulted in ∼3% and ∼7% increase in cell and nisin yields, respectively. This proof-of-concept study demonstrates the potential for use of a low/negative value liquid waste stream from soybean processing for production of a high-value fermentation end product.
本研究旨在评估低/负价值大豆乳清（SW）作为替代物的潜力，用于培养乳酸乳球菌亚种。乳球菌生产乳链菌肽。最初，使用 Bioscreen C 微生物板读数仪进行微量滴定板测定，以快速优化培养条件。研究了各种处理方法，以优化 SW 中的乳链菌肽生产，包括 SW 灭菌的不同方法、大豆薄片浆液的超声处理以释放可能的营养物质、稀释和未稀释的 SW 的比较，以及 SW 的营养物质补充。在随后的基于摇瓶的实验中，从 SW 获得的干燥细菌质量和乳链菌肽产量分别为 2.18 g/L 和 619 mg/L，而从复杂培养基（Man-Rogosa-Sharpe 肉汤）中获得的分别为 2.17 g/L 和 672 mg/L。在生产 SW 之前，将大豆薄片浆液（10%固含量）在水中进行超声处理，可使生物量产量增加约 2%，乳链菌肽产量减少约 1%。向 SW 补充营养物质可使细胞和乳链菌肽的产量分别增加约 3%和 7%。这项概念验证研究证明了从大豆加工中低/负价值的液体废物流生产高价值发酵最终产品的潜力。
