Production and Optimization of Conjugated Linoleic and Eicosapentaenoic Acids by Bifidobacterium lactis in Cold-Pressed Soybean Cake

Background and PurposeIn regard to the biosynthesis of conjugated linoleic acid (CLA) and eicosapentaenoic acid (EPA) by some bacteria, the objective of this study was to evaluate the efficiency of solid-state fermentation based on soybean pressed cake (SPC) to produce CLA and EPA by Bifidobacterium lactis. The objective of this study was to evaluate the efficiency of solid-state fermentation based on SPC to produce CLA and EPA by B. lactis. MethodsProcess conditions including humidity, inoculation level, and temperature parameters were optimized by adopting the response surface methodology (RSM) method (response surface method) and the design expert software. Accordingly, a homogeneous SPC paste substrate at 60, 70, and 80% humidity was prepared with different inoculation levels at 30, 37, and 44 degrees C to assess the strain behavior. The introduced SPC consisted of 60% humidity, 2% inoculation level at 37 degrees C, and 60% humidity, and 4% inoculation level at 30 and 44 degrees C; it also included 6% inoculation level at 37 degrees C, 70% humidity at 2% inoculation level, at 30 and 44 degrees C, and 4% inoculation level at 37 degrees C. Also, SPC with 80% humidity at 2% and 4% inoculation levels, and at 30 and 44 degrees C was obtained. To confirm the accuracy of the conditions, an experiment was conducted according to the defined requirements. ResultsThe results were compared with the predicted data, which showed a significant difference. Under optimized conditions, with an inoculation level of 4% on the SPC medium with 70% humidity and at 37 degrees C, B. lactis strains could yield 9cis-, 11 trans-linoleic and eicosapentaenoic at 0.18 and 0.39% of the total fatty acids. ConclusionSo, the potential benefits of using SPC as an inexpensive substrate for the commercial production of CLA and EPA should be noted.

Automated summary

This study evaluated the efficiency of solid-state fermentation with soybean pressed cake (SPC) as a substrate for the production of conjugated linoleic acid (CLA) and eicosapentaenoic acid (EPA) by Bifidobacterium lactis. Optimal process conditions were determined using the response surface methodology, and the results showed that B. lactis strains could produce 9cis-, 11 trans-linoleic, and eicosapentaenoic acids under specific conditions. Therefore, the use of inexpensive SPC as a substrate for commercial production of CLA and EPA has potential benefits.