Berger Ralf G
Institute of Food Chemistry, Gottfried Wilhelm Leibniz Universität Hannover, Callinstrasse 5, 30167, Hannover, Germany.
Biotechnol Lett. 2009 Nov;31(11):1651-9. doi: 10.1007/s10529-009-0083-5. Epub 2009 Jul 16.
Volatile organic chemicals (flavours, aromas) are the sensory principles of many consumer products and govern their acceptance and market success. Flavours from microorganisms compete with the traditional agricultural sources. Screening for overproducers, elucidation of metabolic pathways and precursors and application of conventional bioengineering has resulted in a set of more than 100 commercial aroma chemicals derived via biotechnology. Various routes may lead to volatile metabolites: De novo synthesis from elementary biochemical units, degradation of larger substrates such as lipids, and functionalization of immediate flavour precursor molecules. More recently, the field was stimulated by the increasing preference of alienated consumers for products bearing the label "natural", and by the vivid discussion on healthy and "functional" food ingredients. The unmistakable call for sustainable sources and environmentally friendly production is forcing the industry to move towards a greener chemistry. Progress is expected from the toolbox of genetic engineering which is expected to help in identifying metabolic bottlenecks and in creating novel high-yielding strains. Bioengineering, in a complementary way, provides promising technical options, such as improved substrate dosage, gas-phase or two-phase reactions and in situ product recovery.
挥发性有机化合物（风味物质、香气）是许多消费品的感官要素，决定着它们能否被接受以及在市场上的成功与否。微生物产生的风味物质与传统农业来源的风味物质相互竞争。筛选高产菌株、阐明代谢途径和前体物质以及应用传统生物工程技术，已产生了一套超过100种通过生物技术获得的商业香料化学品。多种途径可能导致挥发性代谢产物的产生：从基本生化单元从头合成、降解较大的底物（如脂质）以及对直接风味前体分子进行功能化修饰。最近，疏远的消费者对带有“天然”标签产品的偏好增加，以及对健康和“功能性”食品成分的热烈讨论，推动了该领域的发展。对可持续来源和环境友好型生产的明确要求正迫使该行业朝着更绿色的化学方向发展。预计基因工程工具箱将取得进展，有望帮助识别代谢瓶颈并创造新型高产菌株。生物工程以互补的方式提供了有前景的技术选择，如改进底物用量、气相或两相反应以及原位产物回收。
