Chemo-Enzymatically Modified Cereal Brans as a Modulator of Healthy Gut Bacteria: An In-Vitro and In-Vivo Study

ABSTRACT

Finger millet, kodo millet, and rice bran were chemo-enzymatically modified, and their prebiotic potential was evaluated using in-vitro human fecal batch fermentation and in-vivo feeding to mice. Modified cereal bran (mCB) from finger millet, kodo millet, and rice bran contained 30%, 17%, and 24% higher content of dietary fiber compared to their respective native bran. Tannin, flavonoids, polyphenols, and phytate content were reduced in the mCBs. Fecal batch fermentation with mCBs enhanced the short-chain fatty acid levels and the abundance of selected gut bacteria such as Bifidobacteria, Lactobacillus, and Bacteroidetes along with propionate and butyrate. In-vivo experiments showed no change in weight gain, blood glucose, and serum lipids. mCB supplementation enhanced the abundance of selected bacteria such as Bifidobacteria, Lactobacillus, and Bacteroidetes and decreased the abundance of E. coli, Klebsiella, and Clostridium. These findings provide an insight into the functional food potential of valorized mCBs in maintaining a healthy gut environment.

GRAPHICAL ABSTRACT

KEYWORDS:

• Cereal bran
• dietary fiber
• prebiotic potential
• gut bacteria
• short-chain fatty acids

Abbreviations

mCB	=	Modified Cereal Bran
mFMB	=	Modified Finger Millet Bran
mKMB	=	Modified Kodo Millet Bran
SCFA	=	Short Chain Fatty Acid
TPC	=	Total Polyphenol Content
TFC	=	Total Flavonoid Content
TTC	=	Total Tannin Content
HDL-c	=	High Density Lipoprotein-Cholesterol
LDL-c	=	Low Density Lipoprotein-Cholesterol
CFU	=	Colony Forming Units
NPD	=	Normal Pellet Diet
GAE	=	Gallic Acid Equivalent
QE	=	Quercetin Equivalent
CE	=	Catechin Equivalent
TB	=	Total Bacteria

Acknowledgments

The authors would like to thank the Department of Biotechnology, Government of India for the research grant given to NABI under Indo-UK Innovate project- 102755 and for providing fellowship to Ms. Kirti Devi. The authors are grateful to Rajdhani Rice Mill, Samana, India for providing rice bran. We acknowledge Dr. Ajay Kumar Pandey, Scientist-F, NABI, Mohali for providing facilities and help in phytate the estimation. DelCON (DBT e-library consortium) is acknowledged for providing access to journals.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The work was supported by the Department of Biotechnology, Ministry of Science and Technology, India.