Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Jul;133(1):3-17.
doi: 10.1111/jam.15268. Epub 2021 Sep 9.

A novel Bacillus sp. with rapid growth property and high enzyme activity that allows efficient fermentation of soybean meal for improving digestibility in growing pigs

Nadeem Akhtar  1 , Hugh Y Cai  2 , Elijah G Kiarie  1 , Julang Li  1
Affiliations

A novel Bacillus sp. with rapid growth property and high enzyme activity that allows efficient fermentation of soybean meal for improving digestibility in growing pigs

Nadeem Akhtar et al. J Appl Microbiol. 2022 Jul.

Abstract

Aims: Soybean meal (SBM) contributes high-quality dietary protein for pigs. However, it also contains antinutritional factors such as allergenic high molecular weight proteins and non-starch polysaccharides (NSP) that limit its use. Therefore, the objective of this study was to screen and characterize a robust Bacillus sp. from camel dung for soybean meal fermentation to improve the digestibility in growing pigs.

Methods and results: Molecular characterization revealed that isolate 9 (hereinafter referred to as "CP-9") was a Bacillus subtilis strain. It secreted cellulase (0.07 U ml-1 ), xylanase (1.91 U ml-1 ), and amylase (2.66 U ml-1 ) into the culture supernatant. Isolate CP-9 showed rapid growth on LB agar plates and grew at a wide range of pH (3.0-9.0) and temperatures (23-50°C) in LB broth. Protein profiling of SBM using SDS-PAGE showed a significant reduction of large globular proteins to small peptides after 48 h of fermentation. On a dry matter basis, neutral detergent fibre (NDF) of the fermented SBM (F-SBM) was decreased by 34.25% (from 9.72 to 7.24%) with an increase in CP content by 16.54% (from 48.74 to 56.80%). Pigs fed with a semi-purified diet formulated with F-SBM as the sole source of crude protein had higher (p < 0.05) apparent ileal digestibility (AID) of DM (80.0 vs. 71.7%), ash (55.6 vs. 36.1%), CP (84.2 vs. 78.3%), NDF (70.9 vs. 66.0%), and ADF (62.4 vs. 53.3%) compared with pigs fed with unfermented soybean meal (UF-SBM).

Conclusions: A novel Bacillus subtilis strain CP-9 was isolated and characterized from camel dung for efficient fermentation of SBM. This bacterium ameliorates physico-chemical characteristics of F-SBM and improved nutrient digestibility in growing pigs.

Significance and impact of the study: Our data suggest that a low-cost solid-state SBM fermentation was developed using this newly isolated bacterium. The resultant F-SBM improved the nutrient digestibility in growing pigs.

Keywords: Bacillus subtilis; digestibility; extracellular enzymes; pigs; solid-state fermentation; soybean meal.

PubMed Disclaimer

References

REFERENCES

    1. Adeola, O. & Digestion and Balance Techniques in Pigs (2001) Swine nutrition. In: Lewis, A.J. & Southern, L.L. (Eds.) 2nd ed, Washington, DC, USA: CRC Press, pp. 903-916.
    1. Akhtar, N., Aanchal, Goyal, D. & Goyal, A. (2015) Simplification and optimization of media ingredients for enhanced production of CMCase by newly isolated Bacillus subtilis NA15. Environmental Progress & Sustainable Energy, 34(2), 533-541.
    1. Amigo-Benavent, M., Clemente, A., Ferranti, P., Caira, S. & del Castillo, M.D. (2011) Digestibility and immunoreactivity of soybean β-conglycinin and its deglycosylated form. Food Chemistry, 129(4), 1598-1605.
    1. Amoa-Awua, W.K., Terlabie, N.N. & Sakyi-Dawson, E. (2006) Screening of 42 Bacillus isolates for ability to ferment soybeans into dawadawa. International Journal of Food Microbiology, 106(3), 343-347.
    1. Association of Official Analytical Chemists (2000) Official methods of analysis of AOAC International. Gaithersburg, Maryland: AOAC International.