Antifungal activity and mechanisms of ε-poly-l-lysine (ε-PL) against Colletotrichum lagenarium in marrow squash

• Published in: Food science & technology 2024-05, Vol.199, p.116057, Article 116057
• Main Authors: Liu, Chenxia, Liu, Hongru, Wang, Chunfang, Kong, Fanjun, He, Hui, Qiao, Yongjin
• Format: Article
• Language: English
• Subjects: Antifungal activity; Colletotrichum lagenarium; Marrow squash; Plasma membrane; ε-Poly-l-lysine
• ISSN: 0023-6438; 1096-1127
• DOI: 10.1016/j.lwt.2024.116057

Fungal diseases are major adverse factors leading to quality deterioration and spoilage of post-harvest horticultural products. ε-PL is widely recognized as a natural antibacterial agent because of its broad spectrum antimicrobial property. This study was to investigate the antifungal activity of ε-PL against C. lagenarium, and elucidate the underlying mechanism involved. In vivo were also confirmed that ε-PL treatment showed an obvious inhibitory effect for control of anthracnose caused by C.lagenarium in marrow squash. Moreover, in vitro assay showed that ε-PL exerted strongly antifungal activity against mycelial growth on colony diameter, spore germination and mycelium dry weight of C.lagenarium, with the increase of the concentration of ε-PL. Furthermore, compared with the control, damage the cell membrane of C.lagenarium and increase MDA content, significant leakages of intercellular electrolytes, nucleic acid, protein and sugar, suggested that ε-PL treatment increased the membrane permeability of C. lagenarium. Simultaneously, ε-PL significantly inhibited the activity of enzyme related to energy metabolism in C.lagenarium. The results were observed by SEM and TEM that ε-PL treatment damaged the morphology of C.lagenarium. In conclusion, ε-PL concentration higher than 400 mg L−1 might be used as an antifungal agents to control anthracnose caused by C.lagenarium in marrow squash. •ε-PL has excellent antifungal activity against C.lagenarium of marrow squash.•ε-PL damages plasma membrane and leads to cellular leakage of C.lagenarium.•ε-PL mainly causes mycelial membrane damage and disruption of structure and function.•ε-PL can inhibit the decay caused by the anthracnose and prolonged the shelf life of marrow squash.•ε-PL have attractive application prospect in postharvest horticultural products.