Universidad Autónoma de Nuevo León, Facultad de Ciencias Biológicas, Instituto de Biotecnología, Av. Pedro de Alba y Manuel L. Barragán s/n., C. P. 66455 San Nicolás de los Garza, Nuevo León, Mexico.
Centro Interdisciplinario de Investigación para el Desarrollo Integral Regional, (CIIDIR) IPN Unidad Durango, Laboratorio de Bioelectrónica, Calle Sigma 119, Fraccionamiento 20 de Noviembre II, C. P. 34220 Durango, Durango, Mexico.
Int J Biol Macromol. 2021 Apr 1;175:199-208. doi: 10.1016/j.ijbiomac.2021.01.167. Epub 2021 Feb 3.
Lignocellulosic wastes may provide a means to economize polyhydroxybutyrate (PHB) production. This study has proposed the use of Agave durangensis leaves obtained from the artisanal mezcal industry as a novel substrate for this aim. Results revealed an increase in PHB biosynthesis (0.32 g/L) and improvement in %PHB (16.79-19.51%) by Bacillus cereus 4N when A. durangensis leaves used as carbon source were physically pre-treated by ultrasound for 30 min (ADL + US30') and thermally pre-treated (ADL + Q). Chemical analyses and SEM studies revealed compositional and morphological changes when A. durangensis leaves were physically pre-treated. Also, elemental analysis of growth media showed that carbon/nitrogen ratios of 14-21, and low nitrogen, hydrogen, and protein content were well-suited for PHB biosynthesis. Confocal microscopy revealed morphological changes in the bacterial cell and carbonosome structure under the influence of different substrates. Finally, Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) analyses showed that homopolymeric PHB with a high thermal-resistance (271.94-272.89 °C) was produced. Therefore, the present study demonstrates the potential use of physically pre-treated A. durangensis leaves to produce PHB. These results promote the development of a circular economy in Mexico, where lignocellulosic wastes can be employed to produce value-added biotechnological products.
木质纤维素废物可为节约聚羟基丁酸酯（PHB）的生产提供一种方法。本研究提出利用龙舌兰酒工业中获得的龙舌兰 durangensis 叶作为实现这一目标的新型底物。结果表明，当将龙舌兰 durangensis 叶用作碳源并通过超声处理 30 分钟（ADL+US30'）和热预处理（ADL+Q）进行物理预处理时，蜡质芽孢杆菌 4N 的 PHB 生物合成（0.32 g/L）增加，并且 PHB 的百分比（16.79-19.51%）提高。化学分析和 SEM 研究表明，当龙舌兰 durangensis 叶进行物理预处理时，其组成和形态发生了变化。此外，生长培养基的元素分析表明，碳/氮比为 14-21，并且氮、氢和蛋白质含量低，非常适合 PHB 的生物合成。共聚焦显微镜显示，在不同底物的影响下，细菌细胞和碳体结构发生了形态变化。最后，傅里叶变换红外光谱（FTIR）和差示扫描量热法（DSC）分析表明，生成了具有高热稳定性（271.94-272.89°C）的均聚 PHB。因此，本研究表明，物理预处理的龙舌兰 durangensis 叶具有生产 PHB 的潜力。这些结果促进了墨西哥循环经济的发展，其中木质纤维素废物可用于生产高附加值的生物技术产品。
