Qi Bokang, Cai Xinyu, Wang Wenkang, Ma Pengfei, Yuan Xianjun, Tan Xiang
Institute of Ensiling and Processing of Grass, College of Agro-Grassland Science, Nanjing Agricultural University, Nanjing 210095, China.
Citrus Research Institute, Southwest University, Chongqing 400700, China.
Antioxidants (Basel). 2025 Mar 24;14(4):380. doi: 10.3390/antiox14040380.
The study aimed to characterize the antioxidant properties of isolated lactic acid bacteria (LAB) and assess their impacts on fermentation quality and antioxidant status in alfalfa silage. Two LAB strains of XY15 and XY20 and a reference strain of J17 were subjected to antioxidant property evaluation. This was followed by inoculation into alfalfa silage. The DPPH (2,2-diphenyl-1-picrylhydrazyl) and hydroxyl (OH) radical scavenging activities and the glutathione peroxidase (GSH-Px) activity of the cell-free supernatants of YX15 and YX20 were significantly ( < 0.05) higher than those of J17. In all three strains, the superoxide dismutase (SOD) activity was higher in the cell-free supernatants than in the intracellular lysates. Among all three strains, J17 showed the highest total antioxidant capacity (T-AOC) in the cell-free supernatant. Inoculating YX20 and J17 increased lactic acid (LA) concentration and LAB counts, decreased dry matter (DM) loss, ammonia-N concentration, and pH, compared with control (CON) and XY15 inoculated alfalfa silages. After 1 d of ensiling, alfalfa silage inoculated with XY20 exhibited higher SOD activity than other silages. Inoculating XY20 and J17 increased the DPPH free radical scavenging rates in alfalfa silage, compared with CON and XY15 inoculated 90 d-silages. Both YX15 and YX20 demonstrated a dual function of enhancing the lactic fermentation and improving the antioxidant status in alfalfa silage.
本研究旨在表征分离出的乳酸菌（LAB）的抗氧化特性，并评估其对苜蓿青贮饲料发酵品质和抗氧化状态的影响。对XY15和XY20这两株LAB菌株以及J17参考菌株进行了抗氧化性能评估。随后将其接种到苜蓿青贮饲料中。YX15和YX20无细胞上清液的DPPH（2,2-二苯基-1-苦基肼）和羟基（OH）自由基清除活性以及谷胱甘肽过氧化物酶（GSH-Px）活性显著（<0.05）高于J17。在所有三株菌株中，无细胞上清液中的超氧化物歧化酶（SOD）活性高于细胞内裂解物。在所有三株菌株中，J17在无细胞上清液中表现出最高的总抗氧化能力（T-AOC）。与对照（CON）和接种XY15的苜蓿青贮饲料相比，接种YX20和J17可提高乳酸（LA）浓度和LAB计数，降低干物质（DM）损失、氨氮浓度和pH值。青贮1天后，接种XY20的苜蓿青贮饲料的SOD活性高于其他青贮饲料。与接种CON和XY15的90天青贮饲料相比，接种XY20和J17可提高苜蓿青贮饲料中DPPH自由基清除率。YX15和YX20均具有增强苜蓿青贮饲料乳酸发酵和改善抗氧化状态的双重功能。
