Organic Composition and Fatty Acid Profile of Macadamia Nut Oil and Its Impact on the Body Weight of Male Rabbits

Abstract

This study investigated the organic composition and biological effects of macadamia nut oil using GC–MS analysis and an in vivo experimental model. The GC–MS results revealed that macadamia oil is predominantly composed of fatty acid derivatives, with a marked dominance of monounsaturated fatty acids. The principal compound identified was 9-octadecenoic acid (Z)-, methyl ester (26.86%), followed by oleic acid (18.83%) and hexadecanoic acid, ethyl ester (13.32%). Moderate levels of E-9-octadecenoic acid ethyl ester (7.00%) and 8,9,12-octadecatrienoic acid, methyl ester (3.12%) were also detected, indicating the presence of both mono- and polyunsaturated fatty acids. Minor constituents, including eicosapentaenoic acid (1.70%) and other long-chain unsaturated fatty acids (≤1.71%), suggest a diverse lipid profile with potential antioxidant and anti-inflammatory properties. Chromatographic analysis showed well-resolved peaks, with the most abundant compounds eluting between 29 and 31 minutes, confirming the predominance of long-chain fatty acids. Biologically, the results demonstrated a progressive increase in body weight in both control and treated groups. At baseline, no significant difference was observed between the control (1250 ± 45 g) and macadamia group (1245 ± 42 g) (P = NS). After two weeks, body weight increased to 1320 ± 38 g in the control group and 1355 ± 40 g in the treated group, with no significant difference (P > 0.05). However, by week 4, a significant increase (P < 0.05) was recorded in the macadamia-treated group (1480 ± 48 g) compared to the control group (1410 ± 50 g). These findings indicate that prolonged administration of macadamia nut oil may enhance weight gain, potentially due to its high content of bioactive monounsaturated fatty acids. Overall, the study highlights the rich fatty acid composition of macadamia oil and its potential physiological impact on growth performance