There has been much debate on the ultimate fate of

There has been much debate on the ultimate fate of meiobenthos in the ecosystem. The pathways from meiofauna could be linked to macrofauna, nektons and nutrient regeneration (Coull, 1973). It is because majority of meiofauna in the interstitial environment of the Red Sea occur in the top few centimeters of sediment where they are easily accessible to predators including fishes. This hypothesis was supported by many other investigators (Sudarshan and Neelakantan, 1986). The nematodes seem to play the role of conveyer belt and therefore the meiofauna of Red Sea could be considered important as food for higher trophic levels.
In conclusion, a total of 10 meiofaunal taxa were identified at the interstitial habitat of the Red Sea, with meiofauna SCR 7 being primarily dominated by nematodes, harpacticoid copepods, polycheates and ostracodes. The meiofaunal density is influenced by a set of physico-chemical factors of the sediment as well as by the presence of the biogenic structures. The more food availability of mangroves and seagrass meadows, their sediment stability, protection from predators, and their habitat complexity increase the density of meiofaunal community in the Red Sea sediment. Over 50% of the density of all meiofaunal taxa occurred in the upper layer of 0–4cm depth and progressively decreased with increasing depth in the Red Sea sediment.

Acknowledgement
The authors extend their sincere appreciation to the Deanship of Scientific Research at King Saud University – Saudi Arabia for funding this work through Research Group number (RG-1436-242).

Introduction
The surface-active compounds commonly used in many industries are chemically synthesized; they are widely used in almost every sector of recent industry (Samadi et al., 2007). The expansion in environmental carefulness has led to serious consideration of biological surfactants as the most promising alternative to existing product (Henkel et al., 2012). Biosurfactants are considered as one of the high values of microbial products, which have gained considerable interest in recent years that have become an important product of biotechnology for industrial and medical applications (Nitschke and costa, 2007; Makkar et al., 2011). The reasons for their publicity are lower toxicity, specificity of action, simplicity of preparation and extensive applicability. Moreover, they can be used as moistening agents, dispersing agents, emulsifiers, foaming agents, beneficial food elements and detergents in many industrial regions such as: organic chemicals, pharmaceuticals and cosmetics, beverages and foods, metallurgy, mining, petroleum, petrochemicals, biological control and management and many others (Banat et al., 2000; Perfumo et al., 2010; Vedaraman and Venkatesh, 2011). Over the above, biosurfactants have many advantages over synthetic ones, including bioavailability, structural diversity, specific activity at extreme salinity, temperatures and pH (Datta et al., 2011). In spite of these advantages, good attributions and a variety of potential uses of biosurfactants, efforts to commercial production have failed due to the low yield obtained and high production cost. The possibility of economical biosurfactant production to reduce pollution was caused by wastes. Increasing biosurfactant yields and decreasing production costs are essential factors affecting the efficiency of biosurfactant production process (Kosaric, 1992; Bognolo, 1999; Moussa et al., 2006). Syldatk and Hausmann (2010) found that the use of costly substrates, gave low yields and accumulation of undesirable product mixtures rather than refined biosurfactant compounds, such constraints explain why there is restricted production of biosurfactants in industry. Great varieties of agronomic, industrial by-products and material residues are recently available as nutrients for biosurfactant fermentation industry (Makkar and Cameotra, 2002; Savarino et al., 2007; Ferreira, 2008; Silva et al., 2009). Therefore hopefully tomorrow’s microbial surfactants appear to depend particularly on the use of plentiful and cheap substrates for optimization of the operational cultivation conditions, which can markedly increment the yield (Mukherjee et al., 2007, 2008; Mutalik et al., 2008; Makkar et al., 2011). The world production of fats and oils is about 120 million tonnes, 81% of which are from plant sources (Brackmann and Deutschland, 2004). Most of the oils and fats are used in the food industry, which produces large amounts of waste frying oils. The disposal of frying oil waste is causing a great problem, which explains the increasing interest in the use of waste frying oils for microbial transformation (Vedaraman and Venkatesh, 2011). The beneficial effects of this field were paid attention to for isolation and characterization of biosurfactants produced by extremophiles such as halophilic and thermophilic bacteria (Mnif et al., 2009; Kumar et al., 2008; Joshi et al., 2008). This study aimed at isolation of some bacterial isolates from different sources (Oil contaminated soil, uncontaminated soil and from Red sea water at Jeddah region in kingdom of Saudi Arabia [KSA]), then screening assays for biosurfactant production from obtained isolates. The waste frying oil will be reused as a substrate for the production of cheaper biosurfactant.