Author(s): Rajib Tiwari, Rishiram Baral, Nissa Parajuli, Riken Shrestha, Sapana Pun, Ashmita Pahari and Shila Gurung

Abstract: Bacteria are single-celled microorganism which lack nuclear membrane but are metabolically active causing many human diseases making itself an important therapeutic target in pharmacological sciences. Antibacterial agents are the group of materials that fight against such pathogenic bacteria, killing or reducing their metabolic activity. Meanwhile, various infectious diseases caused by virus, bacteria and other sources are being treated by locally available herbal remedies and are gaining interest among various indigenous and ethnic group. This study was conceived to figure out the scientific background of these selected medicinal plants by taking their traditional and local use as a reference basis for selection of these plants. Quantitative phytochemical screening revealed that the ethanolic extract of Cassia fistula showed highest Total Phenolic content (TPC) with 94.63 ±5.22 µg GAE/mg of extract and Aleuritopteris bicolor showed highest Total Flavonoid Content (TFC) with 429.16±7.21µg QE/mg of extract. DPPH free radical scavenging study showed that Aleuritopteris bicolor showed the highest DPPH radical scavenging activity withIC50 value 46.76 μg/ml. Well diffusion method of antibacterial test showed that Cassia fistula showed best antibacterial activity against three bacteria followed by Crinum amoneum. This result coincides with the local and traditional use of these plant materials and provide scientific evidence for their anti-microbial property. This study even paved marvelous pathway for further study of these plant materials.