| Pomegranate, belonging to family Punicaceae, is an edible fruit widely cultivated in China. It is a rich source of various bioactive compounds, which demonstrate not only nutritional but also antioxidant and anti-inflammatory activities, and has thus been extensively used in several traditional medicine systems since ancient times. By now, large amounts of researches on nutritional and antioxidant characteristics of pomegranates have been done. But most of these researches have only focused on one organ or one cultivar. There is still little information on how antioxidants and mineral elements content in pomegranate change depending on organs and cultivars, which are considered to be important endogenous factors influencing nutritional and epidemiological values in many economic crops such as tea. As a result, the selection of cultivar and efficient application of pomegranate are severely limited. The objective of this research was to elucidate the organic and cultivaral trend of nutritional and antioxidant characteristics in pomegranate. Antioxidants and mineral elements content, and antioxidant capacity were investigated in different organs and cultivars of China-grown pomegranates. The results were as follows:1. Polyphenols and flavanoids content and antioxidant capacity in the leaves of pomegranates were of leaf age dependence. The highest polyphenols (126.44 mg·g-1 FW) and flavanoids content (15.37 mg·g-1 FW) and antioxidant capacity (388.87μmol·L-1 FW) were observed in leaf bud. Polyphenols and flavanoids content and antioxidant capacity in young leaves were 101.98 mg·g-1 FW, 13.09 mg·g-1 FW, and 300.45μmol·L-1 FW, respectively. In mature leaves were observed the lowest content of polyphenols (10.56 mg·g-1 FW) and flavanoids (10.56 mg·g-1 FW), and antioxidant capacity (222.38μmol·L-1 FW).2. During a growth season, polyphenols and flavanoids content and antioxidant capacity in leaf bud of pomegranates increased significantly at first and then decreased to great extent. The highest content of polyphenols (124.74 mg·g-1 FW) and flavanoids (15.14 mg·g-1 FW), and antioxidant capacity (476.11μmol·L-1 FW) were observed in leaf bud at fruit-setting stage. Whereas values of the three parameters (55.16 mg·g-1 FW for polyphenols, 10.56 mg·g-1 FW for flavanoids, and 231.32μmol·L-1 FW for antioxidant capacity) in leaf bud were the lowest at the beginning of vegetative growth.3. Mineral elements content in the leaves of pomegranates were influenced by leaf age. The content of potassium, calcium, magnesium, copper and zinc were the highest at the stage of leaf bud, and gradually decreased thereafter. In contrast, iron and manganese content gradually increased with the development of leaf and in the mature leaves were observed the peak content of manganese and iron.4. Mineral elements content in leaf bud of pomegranates were influenced by harvest time. The content of potassium, calcium and magnesium in leaf bud harvested late were higher than that harvested early. In contrast, higher iron and zinc content were observed in the leaf bud harvested early than that harvested late.5. Polyphenols, flavanoids and mineral elements content in the flowers of pomegranates were influenced by anthesis time. Polyphenols and flavanoids content and antioxidant capacity were significantly higher in the flowers of early anthesis (39.24 mg·g-1 FW, 8.52 mg·g-1 FW, and 212.50μmol·L-1 FW, respectively) than those of late anthesis (32.74 mg·g-1 FW, 7.0 mg·g-1 FW, and 134.43μmol·L-1 FW, respectively). The content of potassium, calcium, magnesium, zinc and manganese in the flowers of early anthesis were 19.56～93.08% higher than in the flowers of late anthesis, whereas copper content was 11.04% higher in the flowers of late anthesis than those of late anthesis.6. Different content of polyphenols, flavanoids and mineral elements and antioxidant capacity were observed in different tissues of flowers. Polyphenols and flavanoids content and antioxidant capacity were much higher in the petal (53.46 mg·g-1 FW, 8.32 mg·g-1 FW, and 95.16μmol·L-1 FW, respectively) than in the torus (36.77 mg·g-1 FW, 6.25 mg·g-1 FW, and 61.54μmol·L-1 FW, respectively). The content of potassium, calcium, magnesium and manganese in the torus were 50.19～161.69% higher than in the petal, whereas the higher content of iron, copper and zinc were observed in the petal.7. Polyphenols, flavanoids and mineral elements content and antioxidant capacity in the flowers of pomegranates varied with the development of flower. Polyphenols and flavanoids content and antioxidant capacity decreased with the development of flower. Mineral elements content were the highest at the beginning of flower development, and then gradually decreased to the lowest at the developmental stage of D. Thereafter, mineral elements content slightly increased.8. There was no relationship between the content of polyphenols, flavanoids, and mineral elements in the leaves and fruit color of pomegranates. The highest content of polyphenols and flavanoids were observed in leaf bud of FH-2 (110.90 mg·g-1 FW) and FH-3 (14.52 mg·g-1 FW), respectively, whereas the lowest content of polyphenols and flavanoids were observed in the cultivar of"Honghuayueji". In the mature leaves, the highest content of polyphenols and flavanoids were observes for FH-2 (89.77 mg·g-1 FW and 11.98 mg·g-1 FW), whereas the lowest content of polyphenols and flavanoids were observed for"Fenhuyueji"(35.19 mg·g-1 FW) and"Baihuayueji"(6.80 mg·g-1 FW), respectively. The highest content of potassium, calcium and magnesium were observed in the leaf bud of FH-3, and in FH-3 were observed the highest content of manganese, copper and zinc. In the mature leaves, the highest content of potassium,copper, manganese and zinc were observed for the cultivar of"Fenhuashiliu".9. There were significant differences in polyphenols and flavanoids content between the same organ (leaf, flower, peel, seed or sarcocarp juice) of different cultivars. Polyphenols and flavanoids content ranged from leaves,flower,peel, seed, sarcocarp juice, respectively.
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