1 Extended Abstracts CHARACTERIZATION OF LACTIC ACID BACTERIA ISOLATED FROM MALAYSIAN FOODS Azin Amiri 1 , Hooi Ling Foo 1,4* , Hui Fong Tai 1 , Li Oon Chuah 1 & Teck Chwen Loh 2,5 1 Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences; 2 Department of Animal Science, Faculty of Agriculture; 4 Institute of Bioscience, 5 Institute of Tropical Agriculture, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia. *Corresponding author email: hlfoo@biotech.upm.edu.my Lactic Acid Bacteria (LAB) are a group of Gram-positive bacteria, which are industrially important microorganisms due to their vast applications in various industries. In this study, 10 LAB isolates namely CB1, I-1, OMR1, TB-1, UP2, TP5, GP8, RW18, B12-M9 and Big-2-Y isolated from Malaysian foods were characterized phenotypically and genotypically. The genotypic characterization technique employed in this study was 16S rDNA-Polymerase Chain Reaction amplification, where a pair of universal primers: 8FPL 16S and 1492 16S was used to amplify the 16S rDNA. The amplicon with approximate size of 1.5 kb was then purified and analysed for DNA sequence. Based on the results of 16S rDNA sequence, the isolates of CB1, TB-1 and UP2 were identified as Pediococcus acidilactici, whereas isolates of I-1, OMR1 and B12-M-9 were identified as Pediococcus pentosaceus and the other 4 isolates namely TP5, GP8, RW18 and Big-2-Y were identified as Lactobacillus plantarum with 100% homology. Carbohydrate fermentation profiles were determined for phenotypic characteristics, where the results of API 50 CHL kits showed more than 90% homology for all tested isolates, which were in agreement with the results of 16S rDNA analyses. Antibiotic resistance profile was also determined according to the Kirby-Bauer agar diffusion test using antibiotic impregnated disks. All tested LAB isolates showed resistance to nalidixic acid, streptomycin, vancomycin, gentamycin, kanamycin and bacitracin. However, they were sensitive to tetracycline, chloramphenicol, erythromycin and penicillin G. It is important to determine the antibiotic resistance profile of LAB isolates prior to their application in respective industry since the results in this study showed that some LAB isolates are resistant to several antibiotics being used commonly in livestock industry as growth promoter and disease treatment. Introduction Lactic acid bacteria (LAB) are a group of Gram-positive bacteria. One of the main characteristics of LAB is the ability to ferment sugar to produce lactic acid as the predominant organic acid. Due to long history of LAB in traditionally fermented foods, they have been awarded the status of "Generally Recognized as Safe" by the American Food and Drug Agency