The Research Of Anthocyanin Synthesis Mechanism In The Development Of Blueberry

The quality of fruit is mainly determined by several factors, including fruit color, flavor, Nutritional value etc. For blueberries, fruit color is one of the most important, which is closely related to the type, abundance, and distribution of flavonoids. Blueberries are newly recognized super-fruit for they are rich in anthocyanin, which contributes to a lot of health benefit. So we aim to investigate the change of key quality and enzymes involed in anthocyanin synthesis during blueberry fruit development. To fulfil the goal,’Bluecrop’and’Powderblue’were harvested from full-bloom to ripening every10days, then sugars, anthocyanin, total phenols, flavonoid and related enzymes were analyzed. The results indicated that:1:Developmental roles of key fruit quality for blueberryBlueberry fruit mainly accumulation Hexose, there was marked positive correlation between anthocyanin and Hexose.(Bluecrop, r=0.818*, r=0.835**; Powderblue, r=0.769*, r=0.805*).The total phenolics and flavonoid decreased as the development of blueberry, and increased slightly at the end of development. The contents of anthocyanin increased in the development of blueberry.The contents of Anthocyanin, Phenolics, Sugars, Flavonoid in bluecrop was lower than those of powderblue.2:Research of anthocyanin synthesis enzymes in blueberryThe activity of PAL was not marked correlated with anthocyanin level but was in parallel with the changes of Phenolics and Flavonoid. Their concomitance could be confirmed. Metabolic enzymes involved in the development of the fruit expression gradually lower in the beginning of the development process,and fall to lowest in the middle of fruit development, and then begin to express increases. The contents of anthocyanin in bluecrop and poweder blue related the amount of protein expression enzymes CHS, CHI, DFR, ANS.They are significant positive correlation (CHS r=0.942* , CHI r=0.930**, DFRr=0.910**, ANSr=0.875**), and protein expression of PAL was no significant correlation with anthocyanin (PAL r=0.630). Powder blue anthocyanin content and PAL protein expression is significantly related,(PAL r=0.873**), and corresponding to the enzyme activity. And DFR and no significant correlation between ANS (DFR r=0.334, ANS r=0.679). CHI, CHS, DFR and ANS are the key enzymes in the synthesis of anthocyanin in bluecrop. ANS (the key enzyme synthesis, and PAL is the key enzyme in powder blue synthesis. ANS immunohistochemical positioning results show that ANS mainly distributed in the fruit exocarp, seeds, mesocarp and the vascular bundle.3:Relationship between the developmental roles of key fruit quality and anthocyanin synthesis enzymesDuring the fruit development of Bluecrop, expression of CHI, DFR, CHS and ANS significantly correlated to glucose and fructose content. In Powderblue, expression of PAL and ANS positively rela ted to glucose and fructose content. To some extent, these results indicated that sugar may promote th e expression of anthocyanin synthases, thereby promoting the synthesis of anthocyanin, but the under lying mechanism needs to be further studied.