Impact of key compounds derived from germinated tigernuts (Cyperus esculentus L.) on cells apoptosis and proliferation property

Tigernuts seeds (Cyperus esculentus L.) contain an abundance of phytochemicals, especially germinated ones, which exhibit higher biological activities. This study aimed to investigate chemical compositions, antioxidant and anti-cancer activities of tigernuts in three states: raw (ungerminated) (RE), germinated with either water (WGE) or with Bacillus velezensis fermentation supernatant (SGE). Compared to other two groups, germinated tigernuts (especially SGE) significantly increased the content of syringetin, eriodictyol, jujuboside B, and pseudoprotodioscin, while was positively consistent with their corresponding antioxidant capacities (including ABTS, DPPH, FRAP, and hydroxyl radical scavenging activities). In addition, extract from sample SGE had more content of phloretin, pseudoprotodioscin, and jujuboside B than that of WGE, which was positively correlated with the cell inhibitory effect, demonstrating that effect of SGE group was greater than that of either WGE or RE on cells property. Specifically, SGE treatment increased reactive oxygen species and the number of apoptotic cells, followed by arrested cell cycle at the G2/M phase and enhanced related mRNA expression. To the best of the authors’ knowledge, this is the first evidence for demonstrating the induction of apoptosis in HCT116 cells by the extract of germinated tigernuts, especially the fermentation supernatant of B. velezensis. These findings provide a scientific basis for the use of key compounds from germinated tigernuts in the treatment of cancer, although further in vivo studies are still required. Graphical abstract: (Figure presented.)