Influence of various drying techniques on essential oil content and components of Artemisia pallens Wall. ex DC

Artemisia pallens, popularly known as “davana,” is a highly valued medicinal and aromatic plant, producing essential oil rich in bioactive compounds with significant therapeutic and industrial applications. This study evaluates the impact of various drying methods on the content and composition of davana essential oil, aiming to optimize postharvest processing for improved quality and farmer profitability. Essential oils (EOs) were extracted from shade dried plant samples collected at various time intervals using a Clevenger apparatus and analysed by GC–MS. A total of 24 compounds were identified across different drying durations, with davanone as the major constituent, which is highly prized for the food and fragrance industries. Essential oil content and chemical composition varied significantly with drying time and temperature. The highest essential oil content (0.163 ± 0.025 %) was recorded after 24 h of shade drying, while prolonged drying beyond 48 h led to a decline in both essential oil content and compound diversity. Among the major constituents, davanone peaked at 38.87 ± 3.76 % at 24 h of shade drying, bicyclogermacrene reached a maximum of 14.66 ± 1.41 % at 18 h, and spathulenol was highest at 6.72 ± 1.54 % at 18 h. Heat sensitive compounds such as trans - ethyl cinnamate and (2 E ,6 Z )-farnesol showed significantly lower levels under oven drying ( trans -ethyl cinnamate: 5.93 ± 0.83 % at 60 °C). PCA analysis revealed that fresh and shade-dried samples retained key bioactive compounds better, whereas oven and sun drying caused compositional shifts, likely due to heat induced degradation or transformation. Overall, shade drying for 24 h is optimal for retaining maximum essential oil content and chemical integrity, especially davanone, indicating it as the most suitable method for A. pallens essential oil processing .