Efficient and green preparation of baicalein from Radix scutellariae with deep eutectic solvent pretreated bioconversion of cellulose-based microreactor

• Published in: Sustainable chemistry and pharmacy 2024-12, Vol.42, p.101858, Article 101858
• Main Authors: Jin, Shuang, Ren, Yubin, Cheng, Yupeng, Liu, Weili, Peng, Cailiang, Yang, Bingyou, Kuang, Haixue, Fu, Yujie, Lv, Chen, Cai, Hongyao
• Format: Article
• Language: English
• Subjects: Aspergillus oryzae; bacteria; Baicalein; baicalin; Bioconversion; biotransformation; cell membranes; cellulose; Deep eutectic solvent; green chemistry; magnetism; Microbioreactor; permeability; solvents; temperature; yeasts
• ISSN: 2352-5541; 2352-5541
• DOI: 10.1016/j.scp.2024.101858

To enhance the bioconversion ratio, an efficient and green bioconversion method for the preparation of baicalein with a microreactor composed of edible microorganisms (Aspergillus oryzae and Yeast) treated with deep eutectic solvent co-immobilized on magnetic cellulose was investigated. Various types of deep eutectic solvents (DES) were screened to obtain a superior biocatalytic effect. NADES (CHCL/EG) harvested the maximum catalytic effect at 1.0 wt% under optimal conditions (concentration of bacterium 1.5 × 107 (C × 107 cells/mL), wet weight of microreactor 12 g, incubation temperature 33 °C and pH 5.0, liquid-solid ratio 30:1 (mL/g), incubation time 48 h), baicalein reached 66.36 mg/g, which increased 3.46-fold to that of normal sample after optimizing. DES could increase the permeability of the cell membrane. The bioconversion rate of baicalin reached 97.2%. Moreover, IC50 values of the extracts measured by the DPPH-radical scavenging test were 0.366 mg/mL (control sample 0.674 mg/mL). The residual activity of the microreactor was 80.2 % after using it 14 times. The experimental results showed that bioconversion is an effective method for preparing baicalein from the plants. [Display omitted] •NADES (CHCL/EG) at 1.0 wt% produced 66.36 mg/g baicalein which was 3.46 folds to that untreated.