Chemometric Analysis of Volatile Compounds of NIPRINEEM Oil and Other Brands of Neem Seed Oils Sold in Nigeria

Azadirachta indica A. Juss (neem, family Meliaceae) is a reputable medicinal plant. Various parts of the plant are used as a remedy against different ailments, as a natural pesticide, as raw material in the cosmetic industry, and for marking other commodities. The seed oil is a major product of the plant and its quality depends on the seed quality and extraction methods employed. In this study, the chemical profile of NIPRDNEEM oil is compared with that of other brands of neem seed oils by using gas chromatography-mass spectrometry (GC-MS) and chemometrics. The fatty acid identified in NIPRDNEEM oil were: oleic acid (34.09%), stearic acid (11.4%), linoleic acid (15.94%), palmitic acid (23.4%), arachidic acid (0.73%), and the other compounds were: 1-Monolinoleoylglycerol trimethylsilyl ether (0.95%) and farnesyl alcohol (13.20%). The branded oils were composed predominantly of oleic acid (13.50% - 26.76%), palmitic acid (6.88% - 11.99%), linoleic acid (7.32% - 11.17%), stearic acid (4.29% - 13.08%), and arachidic acid (0.53% - 1.27%). The unbranded oil contained oleic acid (30.04%), stearic acid (14.91%), linoleic acid (14.62%), palmitic acid (12.34%), and arachidic acid (0.93%). Stigmasterol, stigmasterol acetate, and sitosterol were the sterols identified in the oils. Characterization of the fatty acid profile of neem seed oil is vital for industrial and economic purposes. The fatty acids profile of the NIPRDNEEM oil and other neem seed oil were comparable. Both PCA plots and HCA dendrogram from the chemometric analysis shows three main grouping of all samples. While NIPRDNEEM and the local neem oil were grouped, suggesting a high degree of resemblance of both samples.