Valorization of pineapple (ANANAS comosus) peel waste for levan production: Assessment of biological activities

Levan canopies a pivotal role in all the emerging sectors owing to its non-toxic and biodegradable nature. However, their expensive production impeded their commercialization and made them uneconomical. Hence the current work is focused on harnessing the pineapple peel as a viable substrate for bacterial fermentation to promote levan production. Bacterial strains isolated from different sites was assessed for levansucrase activity among which L10 strain an isolate from sugarcane soil had maximum levansucrase activity was further screened for levan production and identified as Bacillus tequilensis through molecular characterization. The identified bacterium was screened for levan production from various minimal medium of which MM4 yielded maximum and the same has been reconstituted with different proportion of pineapple peel hydrolysate. Medium with 30 % peel hydrolysate exhibited maximum levan and biomass production of 1.8 g/L and 3.23 g/L respectively. The harvested EPS was characterized by FTIR, NMR, HPLC, and GPC to elucidate the functional groups and monomeric composition which similar with the previous researches. Anticancerous activity of levan towards MDA-MB-231 cell line was apparent with the down regulation of the anti-apoptotic gene Bcl2 and upregulation the apoptosis genes comparable to cisplatin. Flow cytometry analysis reveals that the cell cycle arrests crop up at G2/M biopolymers whereas cisplatin arrest at G0/G1 biopolymers.