The study of the biodiversity in local bio-fermented solution and the treatment of community wastewater at laboratory scale: wastewater from restaurants

Abstract

Bio-fermented solution is a solution composed of a diverse variety of microbes coexisting together, aiding the metabolism of each other. Nowadays,bio-fermented solution is widely used for many purposes and is one of the popular usages for wastewater treatment. In this experiment, the biodiversity of the bio-fermented solution was determined by selective and non-selective enrichment media. For the treatment of restaurant wastewater (collected from local department store food court and steak restaurant), 0 (control), 0.25, 0.5 and 1 mL of bio-fermented solution were inoculated per liter of wastewater. In the treatment procedure, light (with light and without light), time (24 hours and 48 hours) and oxygen (with oxygen and without oxygen) were varied. After treatment, the wastewater sample’s chemical and microbiological properties were tested. The chemical properties include total solid (TS), Biochemical oxygen demand (BOD), total suspended solid (TSS), total dissolved solid (TDS), pH and grease and oilcontent. The microbiological properties were measured by MPN method and total plate count method. The bio- fermented solution biodiversitieswere contained with Bacillus spp. 3.48×104 CFU.mL-1, mold 3.63×103 CFU.mL-1, lactic acid bacteria 4.35×104 CFU.mL-1, actinomycetes 1.27×105 CFU.mL-1 and yeast 1.35×105 CFU.mL-1. When using bio- fermented solution to treat restaurant wastewater, there were significant reduction of TS and grease and oil at 53.07% and 69.89% respectively. The best condition for restaurant wastewater treatment was 0.25 mL of bio-fermented solution per liter of wastewater without oxygen and light for 48 hours. However, the quality of treated wastewater was still above the standard required. Therefore, further experiment will be needed to improve the quality of water before discarding.