Structural and thermal investigations of starch polymers as matrices for retention of rhynchophorol aggregation pheromone

Abstract

The present study aimed to prepare and characterize amylose inclusion complexes with rhynchophorol aggregation pheromone. The potato and cassava V-amylose–rhynchophorol complexes were successfully obtained, but the B-type polymorph was also formed. The potato (64.6%) and cassava (40.9%) amylose complexes have presented high crystalline indexes, confirmed by the XRD technique. No endothermic peaks associated with the melting of crystalline arrays were noticed between 30 and 100°C. The dynamic TG runs demonstrated that both the degree of order of crystalline arrays and molecular weights influence the thermal stabilities of the V-amyloses-rhynchophorol. The isothermal TG showed that the retention of rhynchophorol seems to be directly proportional to the molecular weights of starch polymers. The recovered rhynchophorol contents were in the order of 10−7 grams per 50 milligrams of dried powders, which would be useful for insect attraction as demonstrated by the GC–MS technique. The starch polymers studied have presented suitable for retention of rhynchophorol guest molecules.