Abstract：
N-acetyl-d-glucosamine (GlcNAc) is a commercially important amino sugar for its wide range of applications in pharmaceutical, food, cosmetics and biofuel industries. In nature, GlcNAc is polymerised into chitin biopolymer, which is one of the major constituents of fungal cell wall and outer shells of crustaceans. Sea food processing industries generate a large volume of chitin as biopolymeric waste. Because of its high abundance, chitinaceous shellfish wastes have been exploited as one of the major precursor substrates of GlcNAc production, both in chemical and enzymatic means. Nevertheless, the current process of GlcNAc extraction from shellfish wastes generates poor turnover and attracts environmental hazards. Moreover, GlcNAc isolated from shellfish could not be prescribed to certain groups of people because of the allergic nature of shell components. Therefore, an alternative route of GlcNAc production is advocated. With the advancement of metabolic construction and synthetic biology, microbial synthesis of GlcNAc is gaining much attention nowadays. Several new and cutting-edge technologies like substrate co-utilization strategy, promoter engineering, and CRISPR interference system were proposed in this fascinating area. The study would put forward the potential application of microbial engineering in the production of important pharmaceuticals. Very recently, autotrophic fermentation of GlcNAc synthesis has been proposed. The metabolic engineering approaches would offer great promise to mitigate the issues of low yield and high production cost, which are major challenges in microbial bio-processes industries. Further process optimization, optimising metabolic flux, and efficient recovery of GlcNAc from culture broth, should be investigated in order to achieve a high product titer. The current study presents a comprehensive review on microbe-based eco-friendly green methods that would pave the way towards the development of future research directions in this field for the designing of a cost-effective fermentation process on an industrial setup.
摘要：
N-乙酰-d-葡糖胺(GlcNAc)是一种重要的商业氨基糖,在制药中有着广泛的应用,食物,化妆品和生物燃料行业。在大自然中,GlcNAc聚合成几丁质生物聚合物，这是甲壳类动物的真菌细胞壁和外壳的主要成分之一。海洋食品加工工业产生大量的甲壳质作为生物聚合物废物。因为它的丰度高,几丁质贝类废物已被用作GlcNAc生产的主要前体底物之一，在化学和酶的手段。然而，目前从贝类废物中提取GlcNAc的过程产生较差的周转并引起环境危害。此外，由于壳成分的过敏性，从贝类中分离出的GlcNAc不能用于某些人群。因此,提倡GlcNAc生产的替代途径。随着代谢构建和合成生物学的发展,目前GlcNAc的微生物合成越来越受到重视。几种新的尖端技术，如基板共同利用战略，启动子工程，和CRISPR干扰系统是在这个迷人的领域提出的。该研究提出了微生物工程在重要药物生产中的潜在应用。最近,已经提出了自养发酵GlcNAc合成。代谢工程方法将提供很大的希望，以减轻低产量和高生产成本的问题，这是微生物生物加工行业的主要挑战。进一步优化工艺,优化代谢通量，从培养液中高效回收GlcNAc，应进行调查，以实现高产品滴度。当前的研究对基于微生物的生态友好型绿色方法进行了全面的综述，这将为该领域未来研究方向的发展铺平道路，以便在工业装置上设计具有成本效益的发酵过程。
