Sangyod rice bran extract enhances growth during the exponential phase and antibacterial activity of supernatant against zoonotic and foodborne pathogens.

Background And Aim: Prebiotics are a group of nutrients or compounds that are degraded by the gut microbiota, including . The probiotic plays an important role in adhesion to the gut and is able to produce antimicrobial substances to inhibit pathogens. This study aimed to investigate the effects of Sangyod rice bran extract on the growth promotion of . Furthermore, antibacterial activity of the extract and supernatants cultured in De Man, Rogosa and Sharpe (MRS) medium plus the extract against zoonotic and foodborne pathogens was investigated.

Materials And Methods: Antibacterial activity of the crude extract and the oil from Sangyod rice bran against the pathogens, including , , , Avian pathogenic , and was investigated using broth microdilution assay. The effects of the crude extract and the oil on the growth and adhesion of . were further determined. The antibacterial activity of supernatant cultured in the medium supplemented with the extract and the oil against the pathogens was determined by agar well diffusion assay, followed by the broth microdilution assay. Finally, the chemical constituents and antioxidant activity of the crude extract and the oil from Sangyod rice bran were investigated.

Results: The crude extract and the oil from Sangyod rice bran enhanced growth during the exponential phase. Furthermore, the crude extract at 0.25 mg/mL significantly enhanced the adhesion of to the surface compared with the control. Both minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values of the crude extract against and were 0.5 and 1.0 mg/mL, respectively. All pathogens were sensitive to the supernatant of with similar MIC and MBC ranging from 12.5% v/v to 50% v/v. However, the MIC and MBC values of supernatant grown in MRS medium plus the crude extract and oil were not significantly different compared to the supernatant obtained from MRS alone. The crude extract had free radical scavenging activities with IC values at 0.61 mg/mL.

Conclusion: The results suggested the potential benefits of the crude extract from Sangyod rice bran for inducing the growth and the adhesion of and inhibiting zoonotic and foodborne pathogens.