Human Oral Squamous Cancer Cell Death Induced by a Lipopeptide Extract from Bacillus amyloliquefaciens

Bacillus spp., established by Chon in 1872, is made up of Gram-positive aerobic or facultative endosporeforming rod-shaped bacteria. The optimal temperature for growth is ranged from 30°C to 40°C, with no growth below 15°C or above 50°C. They are widespread in the environment being found in dust, soil, water, air, and vegetable matter, and are an important source of fine biochemicals, antibiotics, and insecticides. Several species of Bacillus have been reported to be effective against plant pathogens (Yoshida et al., 2001). They can antagonize pathogens by competing for nutrients and alcove, by stimulating the defensive capacities of the host plant and by producing fungal toxic compounds that render the host more resistant to further pathogen ingress (van Loon et al, 1998; Durrant and Dong, 2004). Antibiotics from Bacillus spp. were identified to biosurfactants (Stein, 2005). These compounds, such as lipopeptide, glycolipid, phospholipid, fatty acids, polymeric and particulate biosurfactants, are microbially derived surface-active and amphipathic molecules produced by various microorganisms such as bacteria, filamentous fungi and yeast during growth (Zasloff, 2002; Stein, 2005). Previous studies have indicated that lipopeptides play a major role in disease suppression, because of their high surface activities and antibiotic potential (Romero et al., 2007). To the best of our knowledge, there are few studies on the cytotoxic activities of marine derived lipopeptides, such as cytotoxicity of Bacillus vallismortis metabolites on colon cancer carcinoma cells, the metabolites of Bacillus SW31 (similar to Bacillus firmus) induced apoptosis of