ABSTRACT
Despite the significant removal of chemical oxygen demand (COD) by anaerobic digestion, anaerobically-treated palm oil mill effluent (POME) still contains tannins and other phenolic compounds, resulting in residual COD and a brownish color. In this study, we investigated the removal of tannins from anaerobically treated POME using protein-tannin complexation in conjunction with electrocoagulation. The amino acid composition of the protein, aqueous pH, and protein: tannin ratios were found to be important parameters affecting the tannin removal efficiency. Pig blood protein was superior to casein protein in removing tannins, possibly because it had aspartic acid as the major amino acid component. At an optimal condition with a pig blood protein: tannin ratio of 0.33 (w/w), a current density of 30 mA/cm2, pH 5, and an electrolysis time of 10 min, the removals of tannins, COD, and color were 93%, 96%, and 97%, respectively.
Subject(s)
Plant Oils , Tannins , Animals , Swine , Palm Oil , Plant Oils/chemistry , Waste Disposal, Fluid/methods , Industrial Waste/analysis , Electrocoagulation/methods , Amino AcidsABSTRACT
Thermoanaerobacterium sp. strain PSU-2 was isolated from thermophilic hydrogen producing reactor and subjected to draft genome sequencing on 454 pyrosequencing and annotated on RAST. The draft genome sequence of strain PSU-2 contains 2,552,497 bases with an estimated G + C content of 35.2%, 2555 CDS, 8 rRNAs and 57 tRNAs. The strain had a number of genes responsible for carbohydrates metabolic, amino acids and derivatives, and protein metabolism of 17.7%, 14.39% and 9.81%, respectively. Strain PSU-2 also had gene responsible for hydrogen biosynthesis as well as the genes related to Ni-Fe hydrogenase. Comparative genomic analysis indicates strain PSU-2 shares about 94% genome sequence similarity with Thermoanaerobacterium xylanolyticum LX-11. The nucleotide sequence of this draft genome was deposited into DDBJ/ENA/GenBank under the accession MSQD00000000.
