储存玉米陈化数学模型的建立和机理探讨

RESEARCH ON AGING MATHEMATICAL MODEL AND MECHANISM OF STORED MAIZE

通过对不同储存年限玉米的9个生理生化指标进行测定,以储存时间、生活力、发芽率、呼吸强度为因变量,以脂肪酸值、水溶性酸值、电导率、过氧化氢酶(CAT)活力、过氧化物酶(POD)活力、丙二醛(MDA)含量为自变量分别进行逐步回归建立数学模型.结果表明:所建立的4个方程都筛选出脂肪酸值、POD活力、MDA含量3个指标;以储存时间为新陈度建立的模型为Y=0.026XFAV-0.0012XVPOD+0.21XCMDA-0.66,该数学模型验证得知,以脂肪酸值、POD活力、MDA含量所建立的方程可测算玉米的新陈度.对储存玉米陈化机理的探讨,发现自由基损伤是玉米陈化的主要原因,玉米籽粒内脂肪酸的积累、POD活力的下降、MDA的增加是玉米陈化的最重要表现.

The 9 physiological biochemical indexes of maize stored for different years were measured, using stored time, viability, germination rate, respiratory intensity as the dependent variable, the fatty acid value, water- soluble acid value, electrical conductivity, the vigor of catalase （CAT） and peroxidase （POD）, Con- tent of malondiadehyde （MDA） as the independent variable, the mathematical model were established by stepwise regression principle separately. The results showed that the fatty acid value（FAV）, the vigor of POD （VPOD）, content of MDA （CMDA） were all screened out by the 4 mathematical model; the mathematical model Y=0. 026XFAV-0. 0012XVPOD ＋0. 21XCMDA -0. 66 was founded when stored time as freshness ＆ aging degree, through the validation, the model that founded by the fatty acid value, the vigor of POD, content of MDA could forecast the aging of stored maize. The aging mechanism of stored maize were discussed, it was transpired that the free radical damage was the essential reason for the aging of storage maize, the fatty acid accumulation, reduction of POD vigor, increase of MDA were the most phenomenon of the aging of storage maize.