Studies On The Main Secondary Metabolites And Its Relationship To Quality In Flue-cured Tobacco Of Strong Aroma Style Flue-cured Tobacco

In this study，the five polyphenolic compounds，four alkaloids, and fourplasmids pigment compounds of secondary metabolites in tobacco，with a typicalstrong aroma style flue-cured tobacco in the the ecological conditions of the HenanProvince. The change rule of the variation of these secondary compounds and relatedenzymes, the relationship between the different classes of secondary metabolites inthe site, regional, and their formation with the aroma quality were studied，usingcorrelation analysis and stepwise regression analysis. The results were as follows:1、The dynamic changes of polyphenols and the related enzymesThe accumulation of polyphenolic compounds in the Vigorous period is verylow， topping tobacco polyphenol content higher increase in， when75d aftertransplanting, the accumulation and increases are the highest，changes in the total ismore stable subsequently，the content had a certain level of increase in the mature，inthe later growth period decreased. The change rule of the content of the chlorogenicacid showing a single peak curve Trend, and peaking at the mature stage；the contentof scopolitin had the highest growth rate at the period of75-90d after transplanting；the content of rutin showing irregular trends in the accumulation，had the moresubstantial rise in the preiod of vigorous and maturity.The content compared between the different parts is that the lower leaves> themiddle leaves> the upper leaves. The lower leaves was significantly higher than themiddle and upper parts of the tobacco in the early growth stage, the content of thethree parts is simliar at the period of the maturity of the upper leaves，the content ofthe upper leaves is more than the middle leaves in the period of later growth stage.Chlorogenic acid and rutin showed the same consistent results. Compared between thedifferent pilot，the peak of Xiangcheng county pilot and Fangcheng pilot in differentleaf parts of the period of performance is inconsistent, the content of the Chlorogenicacid, rutin and polyphenols total of the lower parts of tobacco leaves in Fangchengpilot had the peak at75d after transplanting，but45d after transplanting and90d aftertransplanting in the Xiangcheng County.Main related enzymes were: the activity of PPO showing a gradually increasingtrend, a dramatic rise in front of the Dome period，when the maturity achieved thehighest value，at the later growth period lower. POD activity was on the rise at theperiod of45d after transplanting,60d and90d after transplanting had the bimodal,after transplanting,45d-60d, the highest increase was at the. period of45-60d aftertransplanting.It showed the close relationship between the content of polyphenols and PPOactivity. the correlation between chlorogenic acid，total polyphenol and PPO activityreached a significant level at the upper leaves and the middle leaves. The relationshipbetween rutin with PPO activity reached significant at the middle leaves; The relationship between polyphenol with PAL activity was high.2、The dynamic changes of Alkaloids and the related enzymesAt the period of75d after transplanting，Alkaloids had a higher increase，alsowas the accumulation，the trend of content change leveled off at the period of themature. the middle leaves and the upper leaves have a higher increase at the period of75d and90d after transplanting，Slowdown in the late growth stage.TDC activity showed a single peak curve, with smaller increases in early growthstage, when75d after transplanting the highest rate of increase peaked, then fell to itslowest level at90d after transplanting. the relation between Alkaloid content and TDCactivity did not reach significance level, PAL and alkaloids showed a higher level ofpositive correlation. nicotine and alkaloid total and reducing sugar reached a verysignificant level, the correlation with the total sugar reached a significant level;nicotine and anabasine, and free amino acids reached a significant level; alkaloids andtotalthe nitrogen content was negatively correlated and reached significant level andhighly significant level.3、The dynamic changes of Plastid pigments and the related enzymesChlorophyll content showing decreased with the advance of the growth period, atthe early period had the higher content, the later decline, achieved the highest declinein tobacco mature. Carotenoid content in the Vigorous period showing the trend ofreduced，the content of the tobacco β-carotene and total carotenoid showing theincreasing trend at the period of75d after transplanting, and have a greater decline in90d after transplanting.The activity of LOX presents a single peak curve trend, at75d after transplantingtobacco had the highest content，also was the fastest period the Pigments degradationof， as substantial degradation of the plastid pigment, LOX activity wascorrespondingly reduced. Chlorophyll b and LOX activity’s correlation reached asignificant level.4、The content characteristics of polyphenols, alkaloids and plastid pigment influe-cured tobaccoThe content of new chlorogenic acid,4-o-coffee-d-quinic acid, rutin andscopolitin in order to:lower leaves＞middle leaves＞upper leaves; The content ofchlorogenic acid and total polyphenol in order to: middle leaves＞upper leaves＞lower leaves; The content of rutin in order to: upper leaves＞middle leaves＞lowerleaves. The content of alkaloids in typical strong aroma style flue-cured tobaccoranged from1.158-2.045%.in middle flavor tobacco were higher than those of strong aroma style flue-curedtobacco, the difference reached a significant level. Scopoletin content while strongaroma style flue-cured tobacco higher than in the middle flavor tobacco. The contentof alkaloids in middle flavor tobacco were higher than those of strong aroma styleflue-cured tobacco, both reached a significant level of difference between the fivealkaloids components, including nornicotine, anabasine and anatabine achievedbetweena very significant level.5、The relationship of secondary metabolites and aroma qualityThe relation between aromatic amino acid metabolism and polyphenol compounds at the period of45d and75d after transplanting showing a highly significant negativecorrelation in strong aroma style flue-cured tobacco of Henan Province. The relationbetween products of Maillard reaction and polyphenol compounds at the period of75d after transplanting showing a significant negative correlation. Sensory quality andalkaloid content at45d and60d after transplanting showed a significant negativecorrelation. the neophytadiene and chlorophyll content105d after transplantingpresents a significant negative correlation; products degraded by carotene,and thecarotenoid content45d after transplanting showed a significant negative correlation.