膜荚黄芪褐化愈伤组织的结构及代谢组分析OA

To investigate the underlying mechanism of callus browning in Astragalus membranaceus,green callus and browned callus were used as materials.Widely targeted metabolomics,combined with cellular morphology and ultrastructure observations,was employed to systematically analyze the morphological and metabolic changes during browning.The results showed that the browning process was initiated by hormone-mediated excessive accumulation of reactive oxygen species(ROS).The ROS induced lipid peroxidation in cell membranes,which led to the disintegration of ultrastructures such as chloroplasts,mitochondria,and nuclei,and also caused oxidative damage to proteins and nucleic acids.Ultimately,these effects triggered callus senescence and death.In conclusion,this study indicates that callus browning in A.membranaceus is a consequence of ROS overaccumulation,which drives a cascade of cellular damage culminating in death.These findings elucidate the potential mechanisms underlying this phenomenon and provide a theoretical foundation for overcoming key bottlenecks in tissue culture,thereby facilitating the large-scale production of high-quality plantlets.