Biodegradation of High Salinity Fishery Wastes in a 150-L Reactor by Bacillus licheniformis TK3-Y for Reutilization as Liquid Fertilizer

Abstract

High salinity fishery wastes (HFW) containing seaweed and fish waste cause great influence on the local environment. However, the fishery wastes contain biodegradable components such as carbohydrates, proteins and lipids that are able to be converted to useful bioactive substances by useful bacterium. Therefore, we evaluated large scale biodegradation property of 17.5% of salinity HWF containing green seaweed and anchovy waste by Bacillus licheniformis TK3-Y in 150-L fermenter and utilization of HFW biodegraded product as liquid fertilizer. During 7-day biodegradation, the pH increased with increasing cell density. The decrease in DO (dissolved oxygen) and ORP (oxidation-reduction potential) meant that the HFW was actively biodegraded. CODcr (chemical oxygen demand) and T-N (total nitrogen) were also removed by 87.3 and 87.1%, respectively. In addtion, B.licheniformis TK3-Y showed 0.45 U/mL cellulolytic, 1,016 U/mL proteolytic, and 5.92 U/mL lipolytic activities. The 500and 1000fold diluted supernatant from the culture of HFW had no phytotoxicity. In barley hydroponic culture, the 1,000-fold diluted culture supernatant showed a good fertilizing ability. This study indicates the large-scale treatment of HFW and the biodegraded products are sufficient for agricultural value.