The bio-processing of soybean dregs by solid state fermentation using a poly γ-glutamic acid producing strain and its...

Area of Science:

• Agricultural Science
• Microbiology
• Biotechnology

Background:

• Soybean dregs contain anti-nutrients, limiting their use as animal feed additives.
• Bio-transformation offers a potential solution to improve the nutritional value of soybean dregs.

Purpose of the Study:

• To bio-transform soybean dregs using solid-state fermentation (SSF) with Bacillus amyloliquefaciens NX-2S.
• To evaluate the reduction of anti-nutritional factors and the efficacy of fermented soybean dregs as a feed additive.

Main Methods:

• Solid-state fermentation (SSF) of soybean dregs using Bacillus amyloliquefaciens NX-2S.
• Optimization of fermentation conditions including moisture, inoculum size, temperature, pH, and time.
• Analysis of anti-nutrient reduction (trypsin inhibitor, phytic acid, tannin).
• In vivo study using rats to assess feed additive efficacy.

Main Results:

• Maximum poly γ-glutamic acid (γ-PGA) production of 65.79 g/kg achieved under optimized SSF conditions.
• Significant reduction in anti-nutritional factors: trypsin inhibitor (98.7%), phytic acid (97.8%), and tannin (63.2%).
• Fermented soybean dregs increased rat average weight gain by 15.6% and reduced feed-to-meat ratio by 11.3%.

Conclusions:

• SSF is a feasible strategy for processing soybean dregs into a valuable feed additive.
• Bio-transformation effectively mitigates anti-nutritional factors in soybean dregs.
• Fermented soybean dregs show improved nutritional benefits for animal feed applications.