Abstract
OBJECTIVE: This study aimed to investigate the presence of exosome-like nanovesicles in Anoectochilus roxburghii (Wall.) Lindl. (A. roxburghii) and the related active ingredients. METHODS: A. roxburghii-derived exosome-like nanovesicles (ARENVs) were extracted by the differential ultracentrifugation and characterized by transmission electron microscopy and nano-flow cytometry. The components in ARENVs derived from soil-cultured and hydroponic A. roxburghii were identified and quantified by liquid chromatography-mass spectrometry. RESULTS: Nanovesicles with typical exosome characteristics were successfully isolated from A. roxburghii. After analysis and identification, ARENVs were rich in multiple flavonoid components such as isoquercitrin, kaempferol, isorhamnetin, narcissoside, quercetin and rutin. The quantity of flavonoid compounds was higher in ARENVs derived from soil-cultured A. roxburghii than in those from hydroponic A. roxburghii. CONCLUSION: A. roxburghii contains exosome-like nanovesicles, which are rich in active flavonoid ingredients. These active ingredients are more abundant in ARENVs derived from soil-cultured A. roxburghii than hydroponic counterparts. The findings may provide an innovative theoretical basis for further exploration of the medicinal value of A. roxburghii.