关键词: 草莓, 艾叶多糖, 腐败细菌, 抑菌作用, 防腐保鲜

Abstract: To investigate the antioxidant activity，antibacterial effects and potential application of Artemisia argyi polysaccharides in strawberry preservation，Artemisia argyi polysaccharide was extracted by modified water extraction method，and its antioxidant capacity was evaluated by DPPH（1，1‑diphenyl‑2‑trinitrophenylhydrazine）and ABTS［2，2'‑azino‑bis（3‑ethylbenzothiazoline‑6‑sulfonic acid）］free radical scavenging test.The antibacterial effect against strawberry spoilage bacterium Bacillus safranicus a‑2 was analyzed by Kirby‑Bauer filter paper method.The antibacterial mechanism was further investigated by measuring Ca²⁺/Mg²⁺‑ATPase activity，reactive oxygen species（ROS）content and extracellular protein content. Finally，the fresh‑keeping effect was evaluated by strawberry fruit storage test. The results showed that the DPPH free radical scavenging rate of 9.0 g/L Artemisia argyi polysaccharide was 98.50%，and the ABTS free radical scavenging rate of 6.0 g/L Artemisia argyi polysaccharide was 94.20%. 3.0 g/L Artemisia argyi polysaccharide had the highest antibacterial rate against Bacillus safensis a‑2，which was 70.00%.The activity of Ca²⁺/Mg^2‑‑ATPase decreased by 97.81% after 4 h treatment.At 2 h，the intracellular ROS content accumulated to 1.77 times that of the control group.The preservation test showed that polysaccharide treatment could significantly delay the increase of strawberry decay index，reduce the loss of soluble solids，and increase the fruit hardness by 47.85%compared with the control group（sterile water treatment），exhibiting excellent preservation effects.In summary，Artemisia argyi polysaccharide has significant antioxidant and antibacterial activities. It can exert antibacterial effects by destroying cell membrane function and interfering with energy metabolism，thereby effectively extending the storage period of strawberry.It provides a theoretical basis and practical basis for the development of natural fruit and vegetable preservatives.

Key words: Strawberry, Artemisia argyi polysaccharide, Spoilage bacteria, Antibacterial effect, Antiseptic preservation