Preliminary locality-associated variation in volatile organic compounds and antimicrobial activity of Etlingera coccinea essential oils collected from Sabah, Malaysia

Vincent J, Benjamin MAZ, Shamsudin NA, Ason FE, Jaziri AA, Mohd Mokhtar RA, Awang MA, Rusdi NA. 2026. Preliminary locality-associated variation in volatile organic compounds and antimicrobial activity of Etlingera coccinea essential oils collected from Sabah, Malaysia. Biodiversitas 27 (9): d270924. https://doi.org/10.13057/biodiv/d270924. Etlingera coccinea (Zingiberaceae) is an aromatic species traditionally used as food and ethnomedicine in Sabah, Malaysia. This study characterized the Volatile Organic Compounds (VOCs) and antimicrobial activity of E. coccinea Essential Oils (ECEOs) from six Sabah localities: Ranau, Sandakan, Danum, Ulu Kimanis, Paitan, and Long Pasia. ECEOs were obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry, using three independent biological replicates per locality for VOC profiling and antimicrobial assays. Preliminary locality-associated variation was explored using multivariate analysis, while antimicrobial activity was assessed by disc diffusion. ECEO yields ranged from 0.0223% to 0.0360% (w/w). Neral and citronellyl propionate were the predominant VOCs, forming two preliminary compositional groups, with neral predominating in Ranau, Danum, and Ulu Kimanis and citronellyl propionate in Sandakan, Paitan, and Long Pasia. Certain ECEOs produced notable inhibition against selected bacterial strains, particularly Staphylococcus aureus and Clostridium novyi. Long Pasia produced the largest zone of inhibition against Cryptococcus neoformans, although no standard antifungal positive control was included. Exploratory correlation analysis identified associations between VOC variation and antimicrobial responses but did not establish causation. These findings provide preliminary chemical profiling and antimicrobial screening evidence supporting further investigation of ECEOs and comparison of locality-associated patterns across the sampled populations in Sabah.