Factors that influence the extraction methods of terpenes from natural sources

Due to their various applications, terpenes and terpenoids are secondary metabolites of industrial interest. These compounds can be found in a wide variety of organisms from virtually all biological kingdoms. However, it has been identified that various factors in the production process, such as the place and time of harvest, pretreatments, extraction, and purification, generate differences in the profile of terpenes and terpenoids that can be obtained from organisms. The first factor that influences the extraction of compounds is drying since an inappropriate choice of the drying method can lead to the loss of the compounds of interest or the appearance of others that arise due to the decomposition of the original molecules. Similarly, Soxhlet extraction is the most used method in the recovery of terpenoids due to its high extraction efficiency. However, unconventional extraction methods have proven to be effective alternatives for terpenoid recovery, particularly the use of microwave and high-pressure extraction, as well as the use of unconventional solvents, achieving extraction efficiencies equal to or greater than Soxhlet in shorter times. This review will address the differences observed in the extraction of terpenoids and the main factors that cause them, as well as a comparison of the advantages and disadvantages of the various methodologies for drying, extraction, and separation of these compounds.