College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing, China.
College of Horticulture, Nanjing Agricultural University, Nanjing, China.
Lett Appl Microbiol. 2021 Dec;73(6):741-749. doi: 10.1111/lam.13566. Epub 2021 Oct 13.
Lactic acid bacteria have been used to inhibit the growth of spoilage bacteria in food and animal feeds. For instance, Lactobacillus plantarum 163 can inhibit efficiently the growth of both gram-positive and gram-negative bacteria. In our study, the antibacterial activity of L. plantarum 163 was further improved significantly by genome shuffling. The optimal conditions for protoplast formation and regeneration were 20 mg ml lysozyme and 5 mg ml mutanolysin for 30 min at 37°C using 0·5 mol l sucrose as stabilizer. The protoplasts were inactivated under ultraviolet light for 120 s or heated at 58°C for 20 min. After two rounds of genome shuffling, the inhibitory activity of strain F2-14 was improved by 2·45- and 1·99-fold, respectively, as compared to their parent strains. The prepared antibacterial peptides supernatant (APS) was added to the orange juice to inhibit spores of Alicyclobacillus acidoterrestris (SAA) at 45 and 28°C. Results showed that the growth of A. acidoterrestris was significantly inhibited, and the decrease in total soluble solids, OD value and pH value was also delayed. After treatment with APS, the thermal sensitivity of spores was increased and its D value was reduced to 13·78, 3·87 and 1·47 min at 80, 90 and 95°C respectively.
乳酸菌被用于抑制食品和动物饲料中腐败菌的生长。例如，植物乳杆菌 163 可以有效地抑制革兰氏阳性菌和革兰氏阴性菌的生长。在我们的研究中，通过基因组改组进一步显著提高了植物乳杆菌 163 的抗菌活性。原生质体制备和再生的最佳条件为：37°C 下用 20mg/ml 的溶菌酶和 5mg/ml 的黏菌素处理 30min，以 0.5mol/L 蔗糖作为稳定剂。原生质体在紫外线下照射 120s 或加热至 58°C 20min 失活。经过两轮基因组改组，与亲本菌株相比，菌株 F2-14 的抑制活性分别提高了 2.45 倍和 1.99 倍。将制备的抗菌肽上清液 (APS) 添加到橙汁中，在 45 和 28°C 下抑制耐热性好氧环状芽孢杆菌 (SAA) 的孢子。结果表明，A. acidoterrestris 的生长受到显著抑制，总可溶性固形物、OD 值和 pH 值的下降也得到延缓。经 APS 处理后，孢子的热敏感性增加，其 D 值分别降低至 80、90 和 95°C 时的 13.78、3.87 和 1.47min。
