Throughout the ages, natural products have been the most consistently successful source of lead compounds that have found many applications in the fields of medicine, pharmacy and agriculture. Microbial natural products have been the source of most of the antibiotics in current use for the treatment of various infectious diseases. Since the discovery of penicillin in 1928, studies on soil bacteria and fungi have shown that microorganisms are a rich source of structurally unique bioactive substances. After Penicillin, many other drugs including chlortetracycline, chloramphenicol, streptomycin, erythromycin, rifamycin, lincomycin, cephalosporin C, vancomycin, erythromycin, nalidixic acid, amphotericin B, nystatin, and daunorubicin the antitumor agent were discovered from microorganisms. Currently, many of the pathogens implicated in infectious disease are rapidly developing resistance to the available antibiotics making treatment of these infections very difficult hence the need to look for more effective antibiotics. I. Background Microorganisms have provided a wealth of metabolites with interesting activities such as antimicrobial, antiviral and anticancer. In this study, a total of 50 aquatic microbial isolates from 30 samples (taken from waste polluted soil samples form different industrial areas) were screened by the agar-well diffusion method for ability to produce antibacterial-metabolites. Microorganisms play an essential role in maintaining soil fertility: cycling nutrients, influencing their availability; improving soil structure; supporting healthy plant growth; degrading organic pollutants. Some soil bacteria and fungi cause plant diseases; others are antagonistic to plant pathogens and invertebrate pests. Microorganisms play an essential role in maintaining soil fertility: cycling nutrients, influencing their availability; improving soil structure; supporting healthy plant growth; degrading organic pollutants. Some soil bacteria and fungi cause plant diseases; others are antagonistic to plant pathogens and invertebrate pests. The rhizosphere provides a region of increased microbial activity in which certain groups of bacteria and fungi are more likely to proliferate than in the bulk soil. Some rhizosphere microorganisms originate from the seed but the majority is derived from the soil, in which a plant is growing, and they will be returned to the soil, thus bulk soil and rhizosphere reciprocate impact on microbial communities. This is especially important in the case of plant pathogenic microorganisms and microbial antagonists to pests and pathogens. Any one group of microbes is unlikely to perform with maximum efficiency under all circumstances so genetically diverse populations are needed to provide continuation of important soil processes. Since the relationship between the size, diversity and activity of microbial populations and soil 'quality' is unclear, also how these properties fluctuate throughout the seasons, with crop rotations, and the scale (temporal, spatial) on which they vary, it is difficult to predict effects of changes in agricultural practice, land use, climate, introduction of novel plants, microbial inoculants and pollution on soil quality.