Tong Yucui, Guo He'nan, Abbas Zaheer, Zhang Jing, Wang Junyong, Cheng Qiang, Peng Shuyue, Yang Tiantian, Bai Ting, Zhou Yichen, Li Jinzhuan, Wei Xubiao, Si Dayong, Zhang Rijun
Laboratory of Feed Biotechnology, State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing, China.
School of Medicine, Tsinghua University, Beijing, China.
Front Microbiol. 2023 Sep 7;14:1229952. doi: 10.3389/fmicb.2023.1229952. eCollection 2023.
Postbiotics are an emerging research interest in recent years and are fairly advanced compared to prebiotics and probiotics. The composition and function of postbiotics are closely related to fermentation conditions.
In this study, we developed a solid-state fermentation preparation method for postbiotics with antimicrobial, antioxidant, and anti-inflammatory activities. The antibacterial activity was improved 3.62 times compared to initial fermentation conditions by using optimization techniques such as single factor experiments, Plackett-Burman design (PBD), steepest ascent method (SAM), and central composite design (CCD) methods. The optimized conditions were carried out with an initial water content of 50% for 8 days at 37°C and fermentation strains of J and SN4 at a ratio of 1:1 with a total inoculum size of 8%. The optimized SSF medium content ratios of peptide powder, wheat bran, corn flour, and soybean meal were 4, 37.4, 30, and 28.6%, respectively.
Under these optimized conditions, postbiotics with a concentration of 25 mg/mL showed significant broad-spectrum antibacterial capabilities against and strong antioxidant activity against ABTS, DPPH, and OH radicals. Moreover, the optimized postbiotics exhibited good anti-inflammatory ability for reducing nitric oxide (NO) secretion in RAW 264.7 macrophage cells in response to LPS-induced inflammation. Furthermore, the postbiotics significantly improved intestinal epithelial wound healing capabilities after mechanical injury, such as cell scratches in IPEC-J2 cells ( < 0.05).
In brief, we developed postbiotics through optimized solid-state fermentation with potential benefits for gut health. Therefore, our findings suggested that the novel postbiotics could be used as potential functional food products for improving body health.
后生元是近年来新兴的研究热点，与益生元及益生菌相比，其研究进展较为先进。后生元的组成和功能与发酵条件密切相关。
在本研究中，我们开发了一种具有抗菌、抗氧化和抗炎活性的后生元固态发酵制备方法。通过单因素实验、Plackett-Burman设计（PBD）、最速上升法（SAM）和中心复合设计（CCD）等优化技术，抗菌活性比初始发酵条件提高了3.62倍。优化条件为初始含水量50%，在37°C下发酵8天，发酵菌株J和SN4比例为1:1，总接种量为8%。优化后的固态发酵培养基中肽粉、麦麸、玉米粉和豆粕的含量比例分别为4%、37.4%、30%和28.6%。
在这些优化条件下，浓度为25 mg/mL的后生元对[具体菌种未提及]显示出显著的广谱抗菌能力，对ABTS、DPPH和OH自由基具有较强的抗氧化活性。此外，优化后的后生元在响应LPS诱导的炎症时，对RAW 264.7巨噬细胞中一氧化氮（NO）分泌的减少表现出良好的抗炎能力。此外，后生元显著提高了机械损伤后肠道上皮的伤口愈合能力，如IPEC-J2细胞中的细胞划痕（P<0.05）。
简而言之，我们通过优化固态发酵开发了后生元，对肠道健康具有潜在益处。因此，我们的研究结果表明，这种新型后生元可作为潜在的功能性食品用于改善身体健康。
