Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, 43400, Selangor, Malaysia.
Bioprocessing and Biomanufacturing Complex, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, 43400, Selangor, Malaysia.
Probiotics Antimicrob Proteins. 2024 Dec;16(6):1907-1924. doi: 10.1007/s12602-023-10200-4. Epub 2023 Dec 12.
Whole-cell immobilisation technology involving ℽ-aminobutyric acid GABA biosynthesis using lactic acid bacteria (LAB) has been extensively studied owing to its numerous benefits over free-living bacteria, including enhanced productivity, improved cell viability, ability to prevent cell lysis and protect cells against bacteriophages and other stressful conditions. Therefore, a novel LAB biocatalyst was developed using various fruit and fruit waste, immobilising a potential probiotic strain, Lactiplantibacillus plantarum B7, via an adsorption method to improve GABA and cell viability. Apple and watermelon rind have been known to be the ideal natural supports for L. plantarum B7 owing to higher GABA and lactic acid production and improved cell viability among the other natural supports tested and selected to be used in repeated batch fermentation (RBF) to improve GABA production and cell viability. In general, immobilisation of L. plantarum B7 on natural support has better GABA and lactic acid production with improved cell viability via RBF compared to free cells. Watermelon rind-supported cells and apple-supported cells could produce nine and eight successful GABA cycles, respectively, within RBF, whereas free cells could only produce up to four cycles. When using watermelon rind-supported cells and apple-supported cells in RBF, the GABA titer may be raised by up to 6.7 (218.480 ± 0.280 g/L) and 6 (195.439 ± 0.042 g/L) times, respectively, in comparison to GABA synthesis by free cells in single batch fermentation (32.65 ± 0.029 g/L). Additionally, natural support immobilised L. plantarum B7 could retain half of its cell viability even after the 12th cycle of RBF, while no cell was observed in control.
利用乳酸菌（LAB）进行γ-氨基丁酸（GABA）生物合成的全细胞固定化技术因其相对于游离细菌具有许多优势而得到广泛研究，包括提高生产力、提高细胞活力、防止细胞裂解以及保护细胞免受噬菌体和其他应激条件的影响。因此，使用各种水果和水果废物开发了一种新型 LAB 生物催化剂，通过吸附法固定一种潜在的益生菌菌株植物乳杆菌 B7，以提高 GABA 和细胞活力。已知苹果和西瓜皮是 L. plantarum B7 的理想天然载体，因为与其他天然载体相比，它们可以生产更高的 GABA 和乳酸，并且可以提高细胞活力，从而被选择用于重复分批发酵（RBF）以提高 GABA 产量和细胞活力。一般来说，与游离细胞相比，固定化的 L. plantarum B7 在天然载体上通过 RBF 具有更好的 GABA 和乳酸生产以及提高的细胞活力。与游离细胞相比，西瓜皮支持的细胞和苹果支持的细胞在 RBF 中分别可以产生九次和八次成功的 GABA 循环，而游离细胞只能产生最多四次循环。在 RBF 中使用西瓜皮支持的细胞和苹果支持的细胞时，与游离细胞在单批发酵中的 GABA 产量（32.65 ± 0.029 g/L）相比，GABA 产量可能分别提高 6.7 倍（218.480 ± 0.280 g/L）和 6 倍（195.439 ± 0.042 g/L）。此外，即使在 RBF 的第 12 个循环后，天然载体固定化的 L. plantarum B7 仍能保留其一半的细胞活力，而对照中则没有观察到细胞。
