Raveh, E., Gilat Research Center, Agricultural Research Organization, Ministry of Agriculture, Mobile post, Negev 85280, Israel
Saban, T., Department of Clinical Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, PO Box 653, Beer-Sheva 84015, Israel
Zipi, H., Gilat Research Center, Agricultural Research Organization, Ministry of Agriculture, Mobile post, Negev 85280, Israel
Beit-Yannai, E., Department of Clinical Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, PO Box 653, Beer-Sheva 84015, Israel

BACKGROUND: New pomelo and mandarin scion varieties growing under subtropical arid conditions were investigated for total antioxidants in the juice. Four different rootstocks - sour orange (Citrus aurantium (L.); SO), Volkamer lemon (C. volkameriana (Ten & Pasq.)), SB812 (C. sunki (Hort. ex Tan.) × Poncirus trifoliate (L.)) and C. macrophylla (Wester) - were tested. RESULTS: Fruit juice was tested for total antioxidants, ascorbic acid and total polyphenol contents. Cyclic voltammetry (CV) analysis revealed three different antioxidant groups for pomelo and four groups for mandarin. CV analysis for the pomelo scion/rootstock combinations showed that ascorbic acid concentration was highest for scions grafted onto SO.Total polyphenol levels were similar among the pomelo varieties. Mandarin analysis revealed that 'Merav' scion/SO had the highest ascorbic acid concentration (1.91 ± 0.01 mmol L-1). Total polyphenol analysis discovered that 'Merav' 4/119-/SB812 gave the highest levels, while 'Ora Shani' scion grafted on to any tested rootstock contained the lowest. CONCLUSION: We suggest that the SO rootstock is superior to Volka, 812 and macrophylla in terms of juice antioxidant capacity. For the pomelo, both 'Flamingo' scions were found to have high antioxidant production capacity, with 'Flamingo' 3/73 being slightly superior regardless of the rootstock. The best mandarins were 'Merav' hybrids in combination with SO rootstock. © 2009 Society of Chemical Industry.