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BACKGROUND Vanillin is an important flavoring and aromatic ingredient found mainly in the pods of the tropical plant vanilla and is widely used in the food industry. Attempts have been made to produce vanillin from ferulic acid esters in agricultural residues of wheat bran. RESULTS The results showed that a strain with high tolerance to the substrate ferulic acid was isolated and screened from soil and identified as belonging to the genus Bacillus (Bacillus megaterium). The concentration of vanillin produced by this strain was 0.048 g/L and the molar conversion of vanillin was 12.25%. The production of vanillin was optimized by orthogonal experiments. Beef pastes 6.0 g/L, soybean meal 5.0 g/L, MgSO4 ·7H2O 1.0 g/L, FeSO4 ·7H2 O 1.0 g/L, CaCl2 1.0 g/L, K2 HPO4 ·3H2 O 1.0 g/L; fermentation culture conditions were: pH 7.0, inoculum level 5%, loading volume 20%, ferulic acid 1.0 g/L, fermentation culture temperature 35 °C. The concentration of vanillin obtained was 0.218 g/L. Finally, transcriptomic analysis of the strain samples before and after the optimization of the fermentation conditions was carried out to study the effect of the optimization of the fermentation conditions on the concentration of vanillin produced by the strain. CONCLUSION This study provides a theoretical basis for further improving the yield of vanillin and gradually realizing efficient industrial production. This article is protected by copyright. All rights reserved.