Gas Chromatographic Profiling of Volatile Compounds in Neem Leaf Essential Oil from Zamfara State

Azadirachta indica, commonly known as neem, is extensively cultivated across Northern Nigeria and is used traditionally for the management of skin infections, malaria, and inflammatory conditions. The essential oil derived from neem leaves contains a complex array of bioactive volatile compounds responsible for its pharmacological properties. This study profiled the volatile composition of essential oil extracted from neem leaves collected from Gusau, Zamfara State in North West Nigeria using Gas Chromatography with Mass Spectrometry detection. Hydrodistillation was used for oil extraction, and yield was calculated as percentage weight. GC-MS analysis was performed against the NIST spectral library for compound identification. The essential oil yield was 0.84% w/w. A total of 34 volatile compounds were identified, with azadirachtin precursors, limonene, caryophyllene, and alpha-pinene among the major constituents. Minor components included geraniol, linalool, and camphor. The composition differed notably from published profiles of neem oils sourced from South East Asian and Central African samples, suggesting geographical influence on secondary metabolite accumulation. The identified terpenoid profile supports the reputed antimicrobial and anti-inflammatory activities of neem oil. The findings provide baseline chemotypic data for neem populations in Zamfara State relevant to standardisation efforts. Keywords: neem essential oil, GC-MS, volatile compounds, Zamfara State, Azadirachta indica.