Spirulina platensis protein hydrolysates were prepared by digesting protein extracts with papain, and the hydrolysates were separated into 30, 10, and 3 kDa weights using membrane ultrafiltration. The 0–3 kDa low-molecular-weight Spirulina peptides (LMWSPs) proved the highest chemical antioxidant activity by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability, hydroxyl radical (·OH) scavenging activities and total antioxidant capacity. Cellular antioxidant ability of LMWPs fractions against 2000 μg/mL H₂O₂ induced oxidative damage of L02 cells were investigated. The MTT assay results displayed that LMWSPs at different concentrations (0–1000 μg/mL) had proliferation effect on the L02 cells and that treatment of the L02 cells with the 1000 μg/mL LMWSPs (0–3 kDa) significantly prevented H₂O₂-induced oxidative damage compared with control cells. Moreover, the 2′,7′-dichlorofluorescein diacetate (DCFH-DA) fluorescent probe assay showed that the levels of ROS and NO were significantly lower in the experimental group that was treated with the peptides for 24 h than in the control group. Furthermore, using the corresponding kits, the treatment inhibited the reduction of SOD activity and the increase of MDA contents in the L02 cells. Therefore, LMWSPs (0–3 kDa) may have potential applications in antioxidant and liver health products.

通过用木瓜蛋白酶消化蛋白质提取物来制备钝顶螺旋藻蛋白水解物，并使用膜超滤将水解物分离成30、10和3 kDa重量。 0–3 kDa 低分子量螺旋藻肽 (LMWSP) 通过 1,1-二苯基-2-三硝基苯肼 (DPPH) 自由基清除能力、羟自由基 (·OH) 清除能力和总抗氧化能力证明具有最高的化学抗氧化活性。研究了LMWPs组分对2000 μg/mL H ₂ O ₂诱导的L02细胞氧化损伤的细胞抗氧化能力。 MTT法结果显示，不同浓度（0~1000 μg/mL）的LMWSPs对L02细胞具有增殖作用，并且用1000 μg/mL LMWSPs（0~3 kDa）处理L02细胞显着阻止H ₂ O与对照细胞相比， _2-诱导的氧化损伤。此外，2',7'-二氯荧光素二乙酸酯（DCFH-DA）荧光探针检测显示，肽处理24 h的实验组ROS和NO水平显着低于对照组。此外，使用相应的试剂盒，治疗抑制了L02细胞中SOD活性的降低和MDA含量的增加。因此，LMWSP（0-3 kDa）可能在抗氧化剂和肝脏保健产品中具有潜在的应用。