Measurement of antioxidant biological activity of seven food-grad sorghum hybrids grown in a Mediterranean environment

Authors: PONTIERI, PAOLA - Istituto Di Bioscienze E Biorisorse-Uos Portici-cnr; DEL GIUDICE, FABIO - Bioteam Laboratory; DIMITROV, MARTIN - Sofia University St "kliment Ohridski"; PESHEVA, MARGARITA - Sofia University St "kliment Ohridski"; VENKOV, PENCHO - Sofia University St "kliment Ohridski"; DI MARO, ANTIMO - Second University Of Naples; PACIFICO, SEVERINA - Second University Of Naples; Gadgil, Priyadarshin; Herald, Thomas; TUINSTRA, MITCHELL - Purdue University; PIZZOLANTE, GRAZIANO - Universita Del Salento; ROMANO, ROBERTA - Universita Del Salento; ALIFANO, PIETRO - Universita Del Salento; DEL GIUDICE, LUIGI - Istituto Di Bioscienze E Biorisorse-Uos Portici-cnr

Submitted to: Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/8/2016
Publication Date: 8/15/2016
Citation: Pontieri, P., Del Giudice, F., Dimitrov, M.D., Pesheva, M.G., Venkov, P.V., Di Maro, A., Pacifico, S., Gadgil, P., Herald, T.J., Tuinstra, M.R., Pizzolante, G., Romano, R., Alifano, P., Del Giudice, L. 2016. Measurement of antioxidant biological activity of seven food-grad sorghum hybrids grown in a Mediterranean environment. Food Chemistry. 10(7):904-910.

Interpretive Summary: In recent years, there has been growing interest in research into the role of plant-derived antioxidants in food and human health. The antioxidant content of plant foods may contribute to the protection they offer from disease. Sorghum is a good source of antioxidant compounds with a variety of genetically dependent types and levels including phenolic acids, flavonoids, and condensed tannins. The goal of the present study was to measure the antioxidant capacity in grains of seven white food-grade sorghum hybrids bred and adapted for growth in the central USA and grown in a Mediterranean area of Southern Italy. Results show that all samples had similar values for total phenolic content with the Hy F-X715 Ch hybrid exhibiting slightly higher levels than the other hybrids. This research may aid in the selection of white food grade sorghum for growth in Mediterranean environments.

Technical Abstract: In recent years, there has been growing interest in research into the role of plant-derived antioxidants in food and human health. The antioxidant content of plant foods may contribute to the protection they offer from disease. Sorghum is a good source of antioxidant compounds with a variety of genetically dependent types and levels including phenolic acids, flavonoids, and condensed tannins. The goal of the present study was to measure the antioxidant capacity in grains of seven white food-grade sorghum hybrids bred and adapted for growth in the central USA and grown in a Mediterranean area of Southern Italy. To accomplish this, the above sorghum hybrids were analyzed using the bioassay (Ty1antiROS test) and two different chemical assays, i.e., 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and 2,2'-azinobis-(3-ethylbenzothiazolin-6-sulfonic acid) (ABTS) radical assay. All sorghum samples were also analyzed for phenolic contents. The results of Ty1antiROS test show that all seven studied sorghum hybrids possess antioxidant activity with ID50 values between 28 and 250 µg/ml and, while all the samples are effective in scavenging the ABTS•+ target species they exert only a weak DPPH• antiradical effect. Furthermore, results show that all samples had similar values for total phenolic content with the Hy F-X715 Ch hybrid exhibiting slightly higher levels than the other hybrids (44.82 mg gallic acid equivalents [GAE] per 100 g of flour). The correlation coefficient of antioxidant activity analysis among the different methods applied show a positive correlation between the ABTS data and those of DPPH (R = 0.61) and a weakly positive correlation between the ABTS data and those of Ty1antiROS method (R= 0.38).