**4. Final considerations**

This work allowed the obtainment of very interesting data about the use of low value-added raw materials aiming at reducing the costs of the process of sustainable biodiesel production. The raw material used was the oil extracted from the larvae of the Pachymerus nucleorum easily found in the native forests of the mesoregion of Alto Turi (Maranhão, Brazil), which has little or almost no commercial value.

The technology for extraction of oil from the larvae of Pachymerus nucleorum is simple and to be suitable for sustainable production of biodiesel should be optimized, since it has a high acidity index, which hinders its direct use in traditional transesterification. On the other hand, the oil yield in the course of thermal extraction is very inviting, and may have a cost-effective effect, which may contribute to biodiesel being more competitive with fossil diesel.

The results revealed throughout the physical–chemical characterization of the oil (in natura and esterified) and of the biodiesel originating from the larvae of Pachymerus nucleorum indicated that this oil when previously treated can be used in the transesterification process by basic homogeneous catalysis.

Finally, Brazil in view of its geographical location is a country that emerges with a high potential for the development of innovative technologies in the area of renewable energy production, because it has tropical forests with vast biodiversity consisting of tropical forests rich in mineral resources, with exuberant fauna and flora with food, timber, steel, catalytic, medicinal, and renewable energy applications.
