Antitumor and antioxidant activities of levan and its derivative from the isolate Bacillus subtilis NRC1aza

► This study reported in levansucrase isolate Bacillus subtilis NRC1aza. ► The unique feature of this isolate is its ability to produce two types of levans. ► The two levans and their derivatives characterized by strong antioxidants activity. ► SL1 induced intrinsic apoptosis pathway in liver cancer cells. ► The derivatives could be explored as promising antioxidant and antitumor agents.