Oxytetracycline residue alters profiles of microbial communities and metabolites during vegetable fermentation

Abstract:

[Objective] To study the changes in microbial communities and metabolites during the vegetable fermentation exposed to oxytetracycline residue and further provide a theoretical basis for evaluating the effects of antibiotic residue on vegetable fermentation. [Methods] In this study, we determined the oxytetracycline residue by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS), organic acids by high performance liquid chromatography (HPLC), volatile components by the electronic nose and gas chromatography mass spectrometry (GC-MS), microbial species by high-throughput sequencing. [Results] The oxytetracycline residue decreased from 4.00 mg/L to 2.53 mg/L in spontaneous vegetable fermentation. The vegetable without oxytetracycline residue experienced homolatic and heterolactic fermentation, while that with oxytetracycline residue only experienced homolatic fermentation. Meantime, the characteristic microorganisms changed from Lab. pentosus and Lab. plantarum to L. paratarrginis, Lab. buchneri, and Lab.kisonensis. Furthermore, oxytetracycline residue significantly affected the content of lactic acid, citric acid, acetic acid, citronellol, 3-octanol, allylsenevol, geranyl acetate, and phenylethyl isothiocyanate. [Conclusion] Oxytetracycline residue affected the type of vegetable lactic acid fermentation, the succession of microbial communities, and the production of organic acids and volatile compounds. Therefore, the antibiotic residue should be listed as a quality control indicator of raw vegetable materials for fermentation.