Endophytic fungi are promising sources for the production of podophyllotoxin-an important anticancer compound, replacing depleted medical plants. In this study, the endophytes associated with Dysosma difformis-an ethnomedicinal plant species were isolated to explore novel sources of podophyllotoxin. Fifty-three endophytic fungi were isolated and identified by morphological observation and ITS-based rDNA sequencing, assigning them to 27 genera in 3 divisions. Fusarium was found the most prevalent genus with a colonization frequency of 11.11%, followed by Trametes (9.26%) and Penicillium (7.41%). Phylogenetic trees were constructed for the endophytic fungi community in two collection sites, Ha Giang and Lai Chau, revealing the adaptation of the species to the specific tissues and habitats. Cytotoxic activity of endophytic fungal extracts was investigated on cancer cell lines such as SK-LU-1, HL-60, and HepG2, demonstrating strong anti-cancer activity of six isolates belonging to Penicillium, Trametes, Purpureocillium, Aspergillus, and Ganoderma with IC 50 value of lower than 10 10 µg/mL. The presence of podophyllotoxin was indicated in Penicillium, Trametes, Aspergillus and for the first time in Purpureocillium and Ganoderma via high-performance liquid chromatography, which implied them as a potential source of this anticancer compound.

Objective: To investigate the cause of a botulism outbreak in several provinces in Viet Nam in 2020. Methods: An initial investigation was conducted to confirm the outbreak and to form hypotheses about the potential causes, followed by a case–control assessment of the plausible causative food item. Collected food samples were tested to identify the pathogen, and mouse bioassays were performed. Control measures were introduced to stop the outbreak and to prevent similar events in the future. Results: Twelve people in six southern provinces of Viet Nam were identified as having symptoms of botulism, of whom 11 were in critical condition requiring breathing support. A history of foods eaten in the 4 days before illness onset indicated that all the cases had eaten a tinned vegetarian pate, and a case–control assessment showed that this was significantly associated with the outbreak, with an odds ratio of 35.2 (95% confidence interval: 3.4–infinity). Clostridium botulinum type B was detected in three of eight pâté samples collected from the houses of cases. In the mouse bioassay for the toxicity of the pâté samples, all the mice died with clinical symptoms of botulism. Discussion: A tinned vegetarian pate was the plausible cause of a botulism outbreak in Viet Nam in 2020. Revision of food safety regulations to improve quality control of tinned foods to prevent future outbreaks is recommended.