1. Partitioning of Antioxidant /Antiradical Activities and Antioxidant Compounds Between Dried Dates (Tamers) and Date Syrup (Dibs) Fatima Jaffer Ahmed, supervised by Dr. Ameer Al-Laith Fatima Jaffer Ahmed, supervised by Dr. Ameer Al-Laith Biology Department, Science college, University of Bahrain Reactive oxygen species (ROS) and free radicals are substance that can cause severe damage to the tissues and organisms when produced internally. However, in our body, there are specific substances that can prevent their formation or protect against their harmful effect by delaying, preventing oxidation or radical formation at relatively low concentration. These substrates are called antioxidants and antiradicals. Date palm fruits are a rich source of phenolic compounds which possess antioxidant and antiradical activities. The concentration of these compounds varies with cultivar and maturity stages. Samples Tamer of four cultivars (Khalas, Khunaizi, Ruzaiz and Selawi) from Bahrain and Saudi Arabia and three Bahraini date-dibs. 1Al-Farsi et al. (2005) J. Agri. F. Chem. 53:7586–7591. 2Biglari et al. (2008) F. Chem. 107(4): 1636-1641. 3Halliwell et al. (1991) Amer. J.Med. 91(3C): 14S-22S. 4Halvorsen et al (2002) J. Nutr. 132: 461-471. 5Mansouri et al. (2005) F. Chem. 89(3): 411-420. 6Vinson et al. (2005) J.Amer.Col. Nutr. 24(1):44–50. Figure 1: The figure shows the antioxidant activities (FRAP values) of fresh dates, tamers and dibs of two cultivars (Khalas and Khunaizi). Figure 2: The figure shows that the total phenolics of fresh dates is higher than that of tamers, but of tamers is lower than that of dibs. Figure 3: the total flavonoids of fresh dates is higher than that of tamers, but of tamers is lower than that of dibs. Table 1: FRAP value, DPPH inhibition, OH inhibition, and NO inhibition of fresh, tamer and dibs of the cultivars Khalas and Khunaizi a. a, Data are expressed as mean ± SD (n=3). The mean ± SD followed by the same letter, within a column, are not significantly different (p>0.05), b, the standard at 5 mg. Table 2: Antioxidant components of fresh, tamer, and dibs of the cultivars Khalas and Khunaizi a. a, Data are expressed as mean ± SD (n=3). The mean ± SD followed by the same letter, within a column, are not significantly different (p>0.05), b, not determined Antioxidant and antiradical activities were higher in dibs than in tamer The higher antioxidant/antiradical activities of dibs resulted from the partitioning of compounds that normally contribute to the antioxidant/ antiradical abilities between tamer and dibs, since most phenolics are water soluble and can leak out from tamer to dibs. The major contributors to antioxidant/antiradical activities were the phenolic compounds Materials and Methods Introduction The overall FRAP value (mmole/100g) of tamers is lower than that in dibs (Table 2). It can be inferred that the increase in FRAP value of dibs was due to the soluble components that leaked from tamer to dibs and has antioxidant activities such as phenolic compounds The amount of Khalas and Khunaizi dibs were needed to scavenge the 50% of NO., DPPH. and. OH radical is lower than that of tamer of the same cultivars, indicating that dibs exhibited higher antiradical activity than tamer. The anthocyanins and carotenoids contents (mg/100g) were lower in dibs than in the tamer, which may be attributed to several environmental factors including heat, light, temperature and storage. The free phenolics, total phenolics and total flavonoids (g GAE/100g) were higher in dibs than in tamer. This indicates that partitioning of the phenolic compounds had occurred from tamer to dibs. Such higher content of phenolics may be responsible for the higher antioxidant and antiradical activity in dibs than in tamer. The free phenolics, total phenolics and total flavonoids (g GAE/100g) are higher in dibs than in tamer. This can indicate that partitioning of the phenolic compounds had occurred from tamer to dibs. Such higher content of phenolics may be responsible for the higher antioxidant and antiradical activity in dibs than that in tamer. Discussion Conclusion References Results Methods The antioxidant/antiradical activities were estimated by four different assays: The Ferric Reducing Antioxidant Power (FRAP) assay. The Diphenylpicrylhydrazyl (DPPH) Radical Scavenging assay. Nitric Oxide (NO) Scavenging assay. Deoxyribose Degradation assay (Hydroxyl (OH) Scavenging assay) The antioxidant/antiradical constituents includes: Total Anthocyanins Total Carotenoids Total Phenolics (free and esterified) Total Flavonoids.