Conversion of squid pens to chitosanases and dye adsorbents via Bacillus cereus

The purpose of this study was to reclaim squid pens for the production of chitosanases and biosorbents of food colorants and industrial dyes via Bacillus cereus fermentation. B. cereus TKU044 produced chitosanases at a high productivity of 2.66 U/mL, when squid pens were used as the sole carbon and nitrogen source. An extracellular chitosanase, with a molecular weight of 43 kDa, was purified 286-fold with a 16% activity yield. TKU044 and five other chitosanase-producing strains of B. cereus have been used as biosorbents to investigate their adsorption capacity on 0.025% (w/v) of colorants and dyes. For colorants, only Red 7 was adsorbed by the five B. cereus cells, whereas all tested B. cereus strains showed adsorption effects with the dyes. The adsorption of Yellow 4 by squid pens before and after 1 day of fermentation by B. cereus was also studied.