The aim of this study was to develop PCR primer sets for the rapid classification of lactic acid bacteria (LAB). Published gene sequences for LAB carbohydrate metabolic enzymes were collected from the NCBI GenBank, and 45 primer sets were designed using the gene sequences. Twelve species of LAB were used as reference strains: Lactobacillus brevis, Lactobacillus farciminis, Lactobacillus fermentum, Lactobacillus hilgardii, Lactobacillus plantarum, Weissella cibaria, Weissella confusa, Weissella kimchii, Leuconostoc citreum, Leuconostoc lactis, Pediococcus acidilactici, and Pediococcus pentosaceus. PCR amplification and gel electrophoresis were performed to verify the specificities of the designed primers. The results showed that the primer set No. 1 of 5'-aacaacaaaatcaccgcaca-3' & 5'- gtcgtcaatgttgtcgatgc-3' for phosphofructokinase amplified PCR products from 5 species of heterofermenter with different molecular weight depending on the genus. Primer set No. 8 of 5'-gcgtcgccgtctcg-3' & 5'- gcctgcggcttttcg-3' produced specific PCR products from three heterofermentative lactobacilli such as L. brevis, L. fermentum, and L. hilgardii. Primer set No. 18 of 5'-gtgacggtgctgtaggttca- 3' & 5'-gcagtcgcttacgccatatt-3' was specifically reacted to homofermentative species including L. farciminis, P. acidilactici, and P. pentosaceus. Hence, the primer sets which were developed in this study could be used as a tool for the classification and differentiation of homo- and hetero fermentative species in lactic acid fermented foods, like as kimchi.

There is a need to improve the efficiency of the existing sanitary treatment facilities, because the effluent standard becomes more stricter and septic sludge increased. Thus, operating processes of sanitary treatment system in M city changed with installation of additional facilities. Process modifications were as follows: Dilution water was added to the next process after primary aeration tank. Some secondary sedimentation sludge was recycled to primary aerator so that most of the organics were stabilized in primary aeration tank under automatic control of dissolved oxygen. The line of effluent from dewatering process flowing to the activated sludge tank was changed to the primary aerator. The primary sedimentation sludge line was linked to a thickener. Polymer was added to the activated sludge tank. The effluent of primary aerator and aerobic digester was recycled from the 5th to the 1st sector. As consequencies of above process modifications, the improvement of removal efficiency was achieved as BOD 54%, COD 42%, SS 61%, T-N 39%, and T-P 12%, respectively.

A comparison of Daphnia magna, Ceriodaphnia dubia and Simocephalus mixtus toxicity test was performed to study the relative sensitivities and discrimination abilities with both pore and elutriate water of Woopo wetland sediments. Sediment risk assessment has been done by standardized preparation method of pore and elutriate water described in the joint US EPA-US Army Crops of Engineers manual. Simocephalus mixtus which was obtained from Woopo wetlands in Korea was cultured and applied to sediment toxicity test. Water quality in Woopo wetland had great site and seasonal variations. S. mixtus was more sensitive than D. magna in heavy metal toxicity test. The toxicity results with S. mixtus reflected the water quality of elutriate and pore water. The results also suggested that S. mixtus could be used as a test organism in estimating potential risk of contaminated sediments.