Fig. 5From: d-Lactic acid production from agricultural residues by membrane integrated continuous fermentation coupled with B vitamin supplementationA 350 h membrane integrated continuous fermentation by L. delbrueckii. Phase I: 0–100 h (YE3); Phase II: 100–200 h (YE1); Phase III: 200–350 h (YE0.5). The dilution rate (D) for continuous operation was set at 0.4 h−1Back to article page