Structure Elucidation and Biological Activity of Two New Trichothecenes from an Endophyte, Myrothecium roridum

Worldwide, many different grains are infected by various fungi that may produce trichothecene mycotoxins. Fungi that produce trichothecenes, as well as the trichothecenes themselves, are potential problems for public health. On the other hand, trichothecenes possess multiple biological activities. Reduced toxicity may result in their applications in the pharmaceutical field. Two new trichothecenes along with seven known trichothecenes were isolated from an endophyte of the herb plant Ajuga decumbens. Their structures were deduced from ID and 2D NMR data. The results of MTT assays revealed that new trichothecene 2',3'-epoxymyrothecine A, 1, and myrothecine A, 3, exhibited much lower toxicity compared to other trichothecenes. New trichothecene 2',3'-epoxymyrothecine A, 1, could induce phosphorylation of JNK (c-Jun N-terminal protein kinase) protein and the PARP (poly ADP-ribose polymerase) cleavage, and eventually induce apoptosis in cancer cells. These results point out the possibility for application of trichothecenes as chemotherapeutic agent.