Methanol extract of Isodon ternifolius (D. Don) KUDO leaves has antimicrobial and antioxidant activities but no neuroprotective activity.

Aruna Chanu Hijam; Arunkumar Singh Koijam; Reena Haobam

doi:10.52756/ijerr.2024.v39spl.016

Aruna Chanu Hijam Department of Biotechnology, Manipur University, Canchipur, Imphal-795003, Manipur, India https://orcid.org/0000-0002-5614-6039
Arunkumar Singh Koijam Insect Bioresources Laboratory, Animal Bioresources Programme, Institute of Bioresources & Sustainable Development, Department of Biotechnology, Govt. of India, Takyelpat, Imphal-795001, Manipur, India https://orcid.org/0000-0001-5778-4932
Reena Haobam Department of Biotechnology, Manipur University, Canchipur, Imphal-795003, Manipur, India https://orcid.org/0000-0002-2994-9493

DOI: https://doi.org/10.52756/ijerr.2024.v39spl.016

Keywords: Bactericidal, free radicals’ quencher, fungicidal, neurotoxicity, phytochemicals

Abstract

Isodon ternifolius (D. Don) KUDO is a medicinal plant traditionally used by the indigenous people of Manipur, India, as a room fumigant and a means to ward off evil spirits. The current study was designed to assess the antimicrobial, antioxidant, and neuroprotective properties of I. ternifolius. The dried leaves of I. ternifolius were heat extracted with methanol (ME) and screened for phytochemical constituents. The antimicrobial activity was investigated against pathogenic microbes. In-vitro antioxidant activity was assessed by 2-deoxyribose, 2, 2´-Azinobis-3-ethylbenzo-Thiozoline-6-sulphonate (ABTS), and 1, 1-Diphenyl-2-Picrylhydrazyl (DPPH) assay methods. The endogenous reactive oxygen species (ROS) level on SH-SY5Y cells was detected using 2′,7′-Dichlorofluorescein diacetate (DCF-DA). The neuroprotective activity of ME was studied in rotenone-treated SH-SY5Y cells. ME was observed to have substantial antimicrobial potential against four pathogenic bacterial strains - B. subtilis, Streptococcus, K. pneumoniae and E. aerogenes and also revealed antifungal activity against C. albicans. ME also showed potent free radical quenching activity in chemical and cell-culture-based DCF-DA assays and possesses high phenolic and flavonoid contents. However, ME did not show neuroprotective activity in rotenone-treated SH-SY5Y cells.

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