Nisha Negi, Richa Kumari, Neha Neha, Aishwarya Aishwarya, Sanya Chauhan, Ritika Sharma, Sony and Sushila Devi*

Department of Microbiology, Himachal Pradesh University Summerhill, Shimla (171005), India

*Corresponding Author: Devi S, Department of Microbiology, Himachal Pradesh University Summerhill, Shimla (171005), India.

Received: January 08, 2025; Published: January 27, 2025

Abstract

Plant growth and its defence mechanism have been facilitated by endophytic microorganism, in symbiotic association with bacteria found in various plant sections. This study, focuses on the isolation and characterization of endophytes utilizing different medicinal herbs like Achyranthes bidentata, Asparagus racemosus, Centella asiatica, Withania somnifera, and Viola odorata, Urtica dioica, Eupatorium adenophorum, Carica papaya, Thuja occidentalis, and Cinnamonum tamala that are well known for their therapeutic efficacy. Endophytic microorganisms were isolated, out of which some were bacterial and some were fungal species. These endophytic organisms were further screened for their antimicrobial, antioxidant, and plant growth-promoting activities. Among fungi, Arthrinium sp. from Cinnamonum tamala exhibited maximum free radical scavenging activity of 93.95%, while Alternaria sp. showed the minimum of 77.32% free radical scavenging activity. In antifungal assays, Alternaria sp. and Fusarium sp. inhibited Aspergillus niger and Penicillium notatum, while Ulocladium sp. inhibited Rhizopus sp. In antibacterial tests, Bipolaris sp. from Thuja occidentalis showed the largest zone of inhibition (32mm), while Alternaria sp. showed the smallest (9mm). Minimum inhibitory concentration (MIC) assays revealed that the fungi ethyl acetate extracts of the effectively inhibited pathogenic bacteria, with MIC values as low as 0.625mg/100μl. These insights reveal the potential of endophytic microorganisms in sustainable agriculture and therapeutic development, offering promising leads for combating antibiotic-resistant pathogens.

Keywords: Antibiotic Resistance; Endophytes; Medicinal Plants; Antioxidant

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Citation

Citation: Nisha Negi., et al. “In Vitro Screening of Bioactive Endophytic Microorganisms Isolated from Medicinal Flora of the Himalayan Region". Acta Scientific Agriculture 9.2 (2025): 84-95.

Copyright

Copyright: © 2025 Nisha Negi., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.