Method for producing 2 '-fucosyllactose through fermentation without antibiotics and IPTG (isopropyl-beta-d-thiogalactoside) inducer

The invention provides a method for producing 2 '-fucosyllactose by fermentation without antibiotics and IPTG (isopropyl-beta-d-thiogalactoside) inducer, which comprises the following steps: (1) inoculating recombinant escherichia coli into a fermentation culture medium to obtain an initial fermentation system; (2) when the dissolved oxygen of the initial fermentation system rises again, supplementing the initial fermentation system with a supplemented culture medium at a supplementing speed of 5-10 mL/L/h, and controlling the pH value of the supplemented fermentation system to be 6.8-7.2; (3) when the OD600 of the fermentation system after material supplementation is raised to 18-22, adjusting the fermentation temperature to 25-30 DEG C, maintaining the fermentation temperature, adding lactose, and then continuing fermentation and intermittently supplementing lactose; according to the method, the fermentation culture conditions of the recombinant escherichia coli are optimized, the fermentation time of the 2