The present work reports with the screening of biofilm-producing bacteria from the dental caries. The dental pathogens showed resistance against various antibiotics and biofilm forming ability at various levels. Among the bacterial strain, Pseudomonas aeruginosa DC-17 showed enhanced biofilm production. Extracellular polymeric substance (EPS) was synthesized by the selected bacterial isolate considerably and contributed as the major component of biofilm. EPS composed of eDNA, proteins and lipids. The total protein content of the EPS was found to be 1.928 mg/mL and was the major component than carbohydrate and DNA. Carbohydrate content was 162.3 mg/L and DNA content of EPS was 4.95 μg/mL. These macromolecules interacted in the matrix to develop dynamic and specific interactions to signalling biofilm to differentiating various environments. Also, the isolated bacteria showed resistant against various commercially available antibiotics. The isolates showed more resistance against penicillin (98%) and were sensitive against amoxicillin. Among the factors, temperature, pH and sugar concentration influenced biofilm formation. Biofilm forming ability of the selected bacterial stain was tested at various pH values and alkaline pH was favoured for biofilm production. Biofilm production was found to be maximum at 40 °C and 8% sucrose enhanced biofilm formation. Biofilm formed by P. aeruginosa DC-17 was resistant against various tested antimicrobials and chemicals.

本工作报道了从龋齿中产生生物膜的细菌的筛选。牙科病原体在各种水平上均显示出对各种抗生素的抗性和生物膜形成能力。在细菌菌株中，铜绿假单胞菌DC-17显示出增强的生物膜产量。所选细菌分离物大量合成了细胞外聚合物（EPS），并成为生物膜的主要成分。EPS由eDNA，蛋白质和脂质组成。发现EPS的总蛋白质含量为1.928 mg / mL，是碳水化合物和DNA以外的主要成分。碳水化合物含量为162.3 mg / L，EPS的DNA含量为4.95μg/ mL。这些大分子在基质中相互作用以发展动态和特异性相互作用，从而向生物膜发出信号以区分各种环境。而且，分离的细菌显示出对各种市售抗生素的抗性。分离株对青霉素的耐药性更高（98％），对阿莫西林敏感。在温度因素中，pH和糖浓度影响生物膜的形成。在各种pH值下测试所选细菌染色剂的生物膜形成能力，并且碱性pH值有利于生物膜的生产。发现在40°C时生物膜产量最高，而8％的蔗糖增强了生物膜的形成。生物膜形成者铜绿假单胞菌DC-17对各种经过测试的抗微生物剂和化学药品具有抵抗力。