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Onion 發問時間: 社會與文化語言 · 1 0 年前

有關兒茶素層析圖的問題

有關兒茶素層析圖的問題

並問如何利用表一應用在圖2

The HPLC detection and quantitative analysis, as

shown in Fig. 2 and Table 1, indicated that the content

of catechins in the dried TP sample was 93.6%. It contained

six main catechins, namely ()-catechin and ()-epigallocatechin

(C and EGC, 5.1%), ()-epigallocatechin gallate

(EGCG, 40.9%), ()-epicatechin gallate (ECG, 30.4%),

()-gallocatechin gallate (GCG, 10.9%) and ()-epicatechin

(EC, 6.3%). A little caffeine (elution time 10.8 min)

was found in the TP sample. In comparison with green

tea infusions, the extracted TP has an analogous composition

and proportion of catechins.

The catechins present in TP exhibit different biological

properties, due to the differences in their molecular structure.

It is reported that the more galloyl groups the catechin

contains, the stronger is its ability to scavenge free

radicals (Cai et al., 2002; Dreosti, 2000). On the other

hand, the ester bond-containing catechins, such as EGCG

and ECG, possess greater ability to inhibit enzymes. EGCG has been the focus of many studies because of its prominent biological functions such as inhibition of enzymes, and inhibition of cell proliferation

and tumour angiogenesis. The EGCG, ECG and GCG

account for more than 82% (w/w) of the TP sample. It is

therefore speculated that TP will take part in complexing

reactions with protein and, to some extent, affect the activities

of digestive enzymes.

圖片參考:http://img527.imageshack.us/img527/8250/97547463mg...

這篇轉至Science Direct網站

http://www.sciencedirect.com/

篇名:

Effects of tea polyphenols on the activities of a-amylase,! pepsin,

trypsin and lipase

已更新項目:

假如Denise網友你有看到這篇請跟我聯絡一下

想問你兒茶素及酵素的問題

因為之前po這一篇被奇摩知識刪掉了

我的mail: onion250@yahoo.com.tw

2 個已更新項目:

TO Denise

你好

我是食品系的

但因為我們對化學所學的事很少

所以老師給一篇文章對我們來說時在是很吃力

真的很抱歉.對你造成麻煩

1 個解答

評分
  • 1 0 年前
    最佳解答

    上次回答過的內容我就不在重覆PO了

    我想你也清楚了~不過我很好奇你的backgroud是什麼?

    因為覺得你好像對於HPLC沒啥概念咧!?@_@

    BTW,你這次的問題是”如何利用表一應用在圖2?”

    表一所表示的是5種不同的catechins

    利用圖2下所描述之HPLC方法

    各打入不同濃度的標準品所得到的response(通常是用peak的面積)所作出的定量曲線(通常會採線性範圍)

    y=ax^2+b (y=peak area; x=濃度;a=slope斜率; b=intercept截距)(表一下方有描述)

    因此我們由圖2所分析綠茶萃取物(TP)的層析圖譜中

    利用積分軟體得到其peak的面積

    再代入表一的定量曲線內,即可得到各個catechins的濃度了

    再把溶解、稀釋TP sample 的液體體積代入計算(你這沒列paper其餘部份我不清楚),即可得到各個萃取出catechins的純量

    再去跟原本的乾燥的綠茶萃取物重量比,就可得到各個 catechins佔TP的比例了(表一最右列即是,其所加總即與文中的93.6%相符)

    因為你指的那個網站http://www.sciencedirect.com/%E8%A6%81%E7%9C%8B%E5...

    所以我無法也懶得再去找全文來詳閱

    還是僅能就你所PO的內容來回答囉!!

    2007-11-09 16:54:27 補充:

    呵呵~~我本身也是唸食品營養的!

    其實很多做分析工作的人

    都是從食品相關科系出來的呦~

    參考資料: 自己~工作多年經驗
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