Title: Research progress in some traditional and non-traditional medicinal species in the USDA, ARS, PGRCU (S9) germplasm collection Authors
Submitted to: Proceedings Assoc for Advancement of Industrial Crops (AAIC) Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: July 22, 2014
Publication Date: N/A
Technical Abstract: Flavonoids and anthocyanins have shown anti-cancer activities in humans. Therefore, fruit and leaves from several accessions of Abutilon theophrasti Medik., and seeds from Desmodium discolor Vogel, D. incanum (G. Mey) D.C., D. intortum (Mill.) Urb., D. sandwicense E. Mey., D. tortuosum (Sw.) D.C., Hibiscus sabdariffa L., and Teramnus labialis (L.f.) Spreng. accessions in the USDA, ARS, PGRCU genetic resource collection could be sources of myricetin, quercetin, kaempferol, isorhamnetin, luteolin, apigenin, and anthocyanins. The objectives of this are to report medicinal plant research progress for flavonoid and anthocyanin index variability among these species. Leaves and seeds from greenhouse or field grown plants were ground to a fine powder and ~0.2 g of tissue was placed in tubes, and weighed. Extraction solvent (60% HPLC-grade methanol with 1.2 M HCl) was added to each, and samples were mixed and incubated. The extracts were centrifuged, filtered, and injected separately for analysis. Separations were performed by reverse phase high performance liquid chromatography using an Agilent 1100. The mobile phase consisted of an HPLC-grade acetonitrile/methanol mix and formic acid in filtered, sterile water. Samples were injected and analytes were monitored with a diode-array detector. Flavonoid standards were used to generate standard curves for peak identification and quantification. An Opti Sciences CCM-200 chlorophyll content meter was converted to a hand-held anthocyanin index meter for measuring cyanidin and pelargonidin monoglucosides. Leaves from each A. theophrasti accession were inserted between the meter and the LED diode 8 weeks after planting. Abutilon theophrasti produced significant variation for leaf anthocyanin indexes (ranging from 6-11) and flavonoids in leaves and fruit (ranged from 0-5 mg g-1). The Desmodium accessions produced significantly greater concentrations of quercetin and kaempferol than the best control (D. incanum, 477072). Three H. sabdariffa accessions produced significantly more myricetin than all other flavonoids (ranging from 268-1925 µg g-1). Significant variations for flavonoid concentrations were detected in T. labialis seeds. More quercetin (ranging from 1-2 mg g-1) was produced in T. labialis seeds than the other flavonoids. These species showed sufficient variation for the development of superior cultivars and will provide government, public and private organizations with nutraceuticals, functional foods, and phytopharmaceuticals.