Mineral composition of the kernel cake from the seeds of five rubber tree clones cultivated in Côte d’Ivoire

The objective of this study was to determine the mineral composition of the kernel cake derived from the seeds of five rubber tree (Hevea brasiliensis) clones commonly cultivated in Côte d’Ivoire (PB217, GT1, IRCA41, IRCA230, and IRCA331). The experiment was conducted at the CNRA Research Center of Bimbresso, Abidjan, from March 2024 to January 2025. Oil extraction was performed using a Soxhlet apparatus with hexane, and mineral profiling was carried out according to AOAC (1990) procedures. Results showed significant variation (p < 0.05) in macro- and micronutrient contents among clones. GT1 exhibited the highest levels of magnesium (526.48 mg/100 g) and potassium (2275.86 mg/100 g), whereas PB217 showed the highest phosphorus (1182.21 mg/100 g), sulfur (561.29 mg/100 g), and calcium (270.39 mg/100 g) concentrations. IRCA331 presented the highest sodium (22.40 mg/100 g), copper (4.89 mg/100 g), and iodine (3.24 mg/100 g) levels. These findings demonstrate the nutritional potential of rubber seed kernel cake as a valuable mineral source for animal feeding and as an organic soil amendment in sustainable agriculture.