Kentucky State University
Acetogenin Activity Levels in the Ripe Fruit of Seven Pawpaw [Asimina triloba (L.) Dunal] Varieties as Determined by the Brine Shrimp Test
Institution
Kentucky State University
Faculty Advisor/ Mentor
Jeremiah Lowe; Kirk Pomper; Sheri Crabtree
Abstract
Pawpaw [Asimina triloba (L.) Dunal] is a native tree fruit in eastern North America. Annonaceous acetogenins are molecules that contain long chain fatty acids and are present in pawpaw fruit and vegetative tissues. These compounds display pesticidal activity, possibly representing a new botanical pesticide for agronomic pest control. Kentucky State University is the site of the USDA Repository for Asimina species, and germplasm evaluation and collection are program priorities. Fruit is a major biomass source for acetogenin extraction, and identification of selections with high and low levels of fruit annonaceous acetogenin activity would allow for breeding programs to focus on breeding for a desired level of acetogenin activity in pawpaw trees. The objectives of this study were to compare annonaceous acetogenin activity in ripe fruit tissues and identify high activity genotypes. Five pawpaw fruits were collected from individual trees of each pawpaw variety and advanced selection (Sunflower, Hi 7-5, Hi 1-4, Hi 1- 14, Haz 1, Haz 1.9, and Haz 2) with known and unknown fruit acetogenin activity. Ten g of fruit pulp were extracted with 70% ethanol and the brine shrimp test was employed to assess acetogenin activity in pulp extracts. Each concentrated extract was transferred to vials at 5, 10, 20, and 50 ppm concentrations of pulp with three replicate vials per concentration. Fruit pulp LC50s were compared to evaluate fruit acetogenin activity.
Acetogenin Activity Levels in the Ripe Fruit of Seven Pawpaw [Asimina triloba (L.) Dunal] Varieties as Determined by the Brine Shrimp Test
Pawpaw [Asimina triloba (L.) Dunal] is a native tree fruit in eastern North America. Annonaceous acetogenins are molecules that contain long chain fatty acids and are present in pawpaw fruit and vegetative tissues. These compounds display pesticidal activity, possibly representing a new botanical pesticide for agronomic pest control. Kentucky State University is the site of the USDA Repository for Asimina species, and germplasm evaluation and collection are program priorities. Fruit is a major biomass source for acetogenin extraction, and identification of selections with high and low levels of fruit annonaceous acetogenin activity would allow for breeding programs to focus on breeding for a desired level of acetogenin activity in pawpaw trees. The objectives of this study were to compare annonaceous acetogenin activity in ripe fruit tissues and identify high activity genotypes. Five pawpaw fruits were collected from individual trees of each pawpaw variety and advanced selection (Sunflower, Hi 7-5, Hi 1-4, Hi 1- 14, Haz 1, Haz 1.9, and Haz 2) with known and unknown fruit acetogenin activity. Ten g of fruit pulp were extracted with 70% ethanol and the brine shrimp test was employed to assess acetogenin activity in pulp extracts. Each concentrated extract was transferred to vials at 5, 10, 20, and 50 ppm concentrations of pulp with three replicate vials per concentration. Fruit pulp LC50s were compared to evaluate fruit acetogenin activity.