What are the current production methods of NMN?

At present, there are three main manufacturing processes of NMN in the market: (1) chemical synthesis, which has low cost, but the main precursor of NMN is NR, and chlorine will be added in the manufacturing process, which is difficult to avoid chemical residues and may cause risks to human body. (2) Fermentation method. At present, NMN mainly produced in Japan adopts this method, which is complicated, time-consuming and costly. The price of NMN in Japan reaches tens of thousands of yuan, which is difficult for ordinary people to afford. (3) Bio-enzyme catalysis technology won the Nobel Prize at the same time. This technology is green, natural and low-cost. It imitates the working process of catalytic enzymes in human body and can produce needed substances in vitro. The third NMN is used for the glorious life in America. The original research on small molecular enzyme catalysis technology shows that the purity of NMN reaches an astonishing 99.99%, and it contains high concentration of microbial elements, rich in nutrient elements, and its absorption efficiency is five times that of traditional NMN.