The members of lactic acid bacteria (LAB) are gram-positive bacteria which have low G+C DNA in their gemones. Genus Lactococcus, Lactobacillus, Streptococcus, Enterococcusbelong to LAB and have been well characterized by microbiological and molecular biological studies. Their chromosomes and their genetic elements such as bacteriophages, plasmids, insertion sequences and transposons can be used as genetic resources of LAB. The completion of whole genome sequence of Lactococcus lactis strain IL1403 will become a major and important step toward opening new possibilities for the development of unused or unknown genes located on its chromosome and those of other related LAB. Many useful genes have also been found on bacteriophages and plasmids: Especially, many genes for resistance against bacteriophages, of which contamination result in serious damage to the dairy and silage-making fermentations, have been identified. Some of these genetic information and application have been granted patents for phage defense. Here, we introduce some genetic resources of LAB, and consider the prospect of their application, possibilities, importance and usefulness for the next century.

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Indonesia has several traditional fermented foods, wherein the process of manufacture is highly dependent on the microorganisms naturally present in the raw materials and in the environment. There are five popular traditional fermented foods in Indonesia, namely tape ketela (fermented cassava tuber), brem (rice wine), tempe kedelai (fermented soybean), urutan (fermented pork sausage), and terasi (fish or shrimp paste).
These products are normally consumed as they are or used as condiments, flavouring and seasoning agents in a variety of foods. During fermentation, microbial activity and the presence of various enzymes, play an active role in the development of the overall quality of finished products.
The production of Indonesian traditional fermented foods is commonly a small scale, labour intensive, and low profit margin operation, which is ideal for industrial participation of lowincome population.
This paper will focus its discussion on the method of production, microbial ecology, biochemical changes, chemical composition, nutritive values and sensory properties of the products.

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Enterococcus faecium WHE 81, isolated from a smear-surface soft cheese, was shown to produce at least two bacteriocins, with high anti-Listeria activity. One of the bacteriocins produced was purified to homogeneity by ammonium sulfate precipitation, desalting on an ODP-90 reversephasecolumn, SP Sepharose HP cation exchange chromatography and C₂2/C₁₈ reverse-phase chromatography. This purification method is superior to the previously published method, resulting in a 2,500-fold increase in the specific activity, and a recovery of 46%. Mass determination and sequencing of this bacteriocin revealed a peptide of 53 amino acid residues with a molecular mass of 5,462.2 Da. Two cysteine residues (positions 23 and 52) form a disulfide bond. The identified peptide is a class II bacteriocin whose sequence is similar to that of enterocin B produced by Enterococcus faecium CTC492, a strain isolated from Spanish dry fermented sausages.

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The in vivo role of Lactobacillus gasseri SBT10239 was investigated to elucidate the effect it has on inhibiting coliforms and fecal enzymes such as β-glucuronidase and β-glucosidase, which are known to metabolically activate carcinogenic compounds in the intestine. L. gasseri SBT10239colonized the intestinal tract of rats and continued to control fecal flora, even after termination of the administration of lactic acid bacteria. The administration of L. gasseri SBT10239 in rats also resulted in significant (P<0.01) inhibition of coliforms and anaerobes. The activity of the fecal enzymes β-glucosidase and β-glucuronidase also decreased significantly (P<0.001) and this correlated well with the decreased number of coliforms and anaerobes found in the intestinal tracts of the rats. Moreover, this strain was able to colonize the intestinal tracts of the rats.

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