Prediction Model of Secondary Substances in Anthocyanins Synthesis of Purple Corn

The aim of this study was to assay the polyphenols,flavonoid,polyphenol oxidase and phenylalnine ammonialyase which were relative to the anthocyanins synthesis of purple corn. The optimization of multiple linear regression model of anthocyanins synthesis was y=4.383 86-0.205 45x1＋5.479 638x2＋0.195 575x4. According to standard partial regression coefficient testing,the result indicated that polyphenols content was negatively correlated with anthocyanins and the relative influence to anthocyanins synthesis was-42.7%; flavonoid content and activity of polyphenol oxidase were positively correlated with anthocyanins of purple corn and the relative influence to anthocyanins synthesis were 71.45% and 73.32% respectively. There was no positive correlation between the activity of phenylalnine ammonialyase and anthocyanins of purple corn. The establishment of multiple linear regression model of anthocyanins synthesis was to provide theory foundation of producing anthocyanins in laboratory.

Comparison of forage yield,silage fermentative quality,anthocyanin stability,antioxidant activity,and in vitro rumen fermentation of anthocyanin-rich purple corn(Zea mays L.) stover and sticky corn stover

The objective of this study was to observe the forage yield, silage fermentative quality, anthocyanin stability, and antioxidant activity during the storage period and in vitro rumen fermentation of anthocyanin-rich purple corn （Zea mays L.） stover （PS） and sticky corn stover （SS）. Forage yield of corn stover was weighed and ensiled with two treatments： （1） hybrid sticky waxy corn stover （control）, and （2） hybrid purple waxy corn stover （treatment）. Samples were stored in mini-silos for periods of 0, 7, 14, 21,42, 63, 84, and 105 d. The results showed that PS had significantly higher （P〈0.05） yields of dry matter （DM）, organic matter （OM）, gross energy （GE）, crude protein （CP）, neutral detergent fiber （NDF）, acid detergent fiber （ADF）, and total anthocyanins than that of the SS. Anthocyanin-rich purple corn stover silage （PSS） showed higher （P〈0.05） levels of DM and CP relative to the sticky corn stover silage （SSS）. Although anthocyanin-rich PSS displayed a lower （P〈0.05） level of pelargonidin-3-glucoside （P3G）, it had higher （P〈0.05） levels of peonidin （Peo） and pelargonidin （Pel） compared to the control. Delphinidin （Del） and malvidin （Mal） were not detected in SSS during the ensilage period; in PSS, Del was no longer detected after 7 d of ensilage. Specifically, total anthocyanins in anthocyanin-rich PSS decreased rapidly （P〈0.05） prior to 7 d of ensilage, and then remained at relatively stable （P〉0.05） constants. Compared to the anthocyanin-rich PSS, SSS displayed significantly higher （P〈0.05） pH value and ammonia nitrogen （NH3-N） content. Propionic acid （PA） at 0 d and butyric acid （BA） during the entire study period were not detected, whereas anthocyanin-rich PSS showed a higher （P〈0.05） level of lactic acid （LA） than that of the SSS. Compared with the SSS extract, anthocyanin-rich PSS extract showed a higher （P〈0.05） level of 2,2-diphenyl-1-picryihydrazyl （DPPH） scavenging activity and displayed a lower （P〈0.05） half maximal inhibitory concentration （IC50） value. Moreover, anthocyanin-rich PSS reduced （P〈0.05） gas production （GP）, and displayed lower levels of immediately soluble fraction and ratio of acetic acid （AA） to PA at 12 h, but the other parameters were unaffected （P〉0.05） relative to the control. Taken together, the results indicated that： （1） anthocyanins could be stable in silage; （2） anthocyanin-rich PSS showed better silage fermentative quality and stronger antioxidant activity; and （3） anthocyanin-rich PSS had no negative effect on rumen fermentation parameters.