الفهرس 
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Abstract
’Probiotics’ are live ’microorganisms’ that have ’health’ benefits for their ’hosts, Athough probiotic’ ’strains can be ’’isolated from a variety of ’’sources, the main criterion for ’’applications is that they come from different ’marine ’sources. Bacterial ’’probiotics commonly used ’include ’Lactobacillus, ’Bifidobacterium, and Streptococcus ’ species, as well as ’Lactococcus lactis and also some Enterococcus ’’organisms. It was found that ’’probiotics have a variety of health ’’benefits for both humans and ’’animals. Probiotics support the growth of ’beneficial ’microorganisms while ’decreasing the ’amount of ’pathogens, optimizing the ’host’s gut microbes balance’, and reducing the risks of ’gastro-intestinal ’diseases.
In this ’’study, isolates were ’identified using microscopically, biochemical and molecular characteristics, as well as the probiotic properties of lactic acid bacteria isolated from ’sea water.
Three hundred ’potential probiotics’’ were isolated from various sea water. Out of them 198 isolates hemolytic showed hemolytic’ ’activity and the others were ’non-hemolytic. Catalase tests’’ were carried out for further confirmation of ’’LAB in one hundred’ and two isolates ’and according to ’the results’ all were negative for ’the catalase test. ’Seven ’isolates showed resistant for ’gastric pH and different ’ranges of ’PH (2.0, 3.0, 4.0, 5.0, 6.0 and 8.0) and these seven isolates ’could tolerate bile salt (0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 1%), ’Antimicrobial efficacy was investigated ’against the most ’common Gram-positive and Gram-negative infections. The activity of ’commercially available ’antibiotics was ’tested against the ’selected isolates, some of them were sensitive ’ to some antibiotics and others were resistant. Following the ’investigation of these isolates’ probiotic ’properties, the safety was determined ’using a cytotoxicity’ assay, Molecular ’identification techniques were used to ’identify probiotics using Phylogenetic ’tree’’ from the [16S’ sequence] data of the two bacterial’ isolated in the this ’study, Enterococcus faecium AUMC-B-450 and Enterococcus faecium AUMC-B-451. Determination’ of secondary’ metabolite via ’GC/Mass in Enterococcus faecium AUMC-B-450 and Enterococcus faecium AUMC-B-451. Using sweet whey and tryptone as a medium for biomass production of Enterococcus faecium SH7 increasing biomass to 1.4 folds compared with MRS medium. The biomass of E.faecium SH7 increased by using central composite design CCD (11 g/l-1) compared with plackett burman design (9.5 g/l-1) to 1.6 fold, the productivity also increased from 0.198 gL-1h-1 to 0.23gL-1h-1 after 48 h respectively. This research suggested that the sweet whey was an effective low-cost material that could be used for culturing probiotic E. faecium by static culture process.
According to the ’results, That the two ’ strains of Enterococcus faecium for ’application as a ’probiotic in ’the food and feed industries in the future, and suggested that the sweet whey was an effective low-cost material that could be used for culturing probiotic E. faecium for ’commercially culture process.