Assessment of Bioactivity of <i>Homalomena aromatica</i> Essential Oil From Northeast India Through Combinative In Vitro and In Silico Approaches

Homalomena aromatica Schott is a valuable medicinal aromatic plant having wide range of applications in ethnobotany, pharmacology, perfumery and flavor industry. Traditionally, various part of H. aromatica such as leaves and rhizomes were applied to treat joint pain, skin diseases, colds, asthma, diarrhea, and jaundice. Whole herbs extracts are used to address muscle weakness, rheumatism, and allergies, purify the blood, treat deafness, and promote wound healing, especially in postpartum women. The present study is subjected to assess anti-inflammatory, anti-diabetic, tyrosinase inhibitory, acetylcholinesterase (AChE), antimicrobial, and genotoxic efficacies of H. aromatica rhizome essential oil (HAEO). To validate the findings of biological assays, in silico methods including Prediction of Activity Spectra for Substances (PASS) tool, target prediction, and molecular docking were employed. Using Clevenger apparatus dry rhizome of HAEO was extracted. The chemical profiling was performed using gas chromatography/mass spectrometry (GC/MS) where HAEO yield was 1.09% ± 0.641% (v/w) with 12 compounds where linalool was identified as major compound (76.29%). Anti-inflammatory activity showed IC₅₀ value for protease inhibitory assay 19.59 µL/mL and albumin denaturation assay 32.16 µL/mL. The IC₅₀ value for α-amylase inhibitory activity showed 29.84 µL/mL, whereas tyrosinase inhibitory activity showed 73.62 µL/mL. Acetylcholinesterase inhibitory (AChEase) activity revealed an IC₅₀ value of 38.13 µL/mL. Antimicrobial activity showed minimal inhibitory concentration (MIC) values of 10 ± 0.47 and 45 ± 0.47 µg/mL against Staphylococcus aureus and Candida albicans. Genotoxicity analysis showed HAEO has moderate toxic effect. In silico results identified six potential targets via Swiss target prediction: (AChE, CYP51, peroxisome proliferator-activated receptor [PPAR], cyclooxygenase-2 [COX-2], and tyrosinase-related protein 1 [TYRP1]). Additionally, molecular docking studies revealed Linalool -7.4 kcal/mol, Spathulenol -8.5 kcal/mol, aromadendrene oxide-(2) -8.3 kcal/mol better docking scores. For the first time, this study reports on anti-diabetic, anti-tyrosinase, acetylcholinesterase inhibitory activities and genotoxicity of HAEO. In silico investigation supports these activities by evaluating binding affinities and interactions between compounds and their respective targets through molecular docking. From the current reports, HAEO can be used for development of natural drugs in near future.