水蜜桃 asked in 社會與文化語言 · 1 decade ago



An optimised procedure is reported for extraction of pectin from pumpkin pulp, using an enzyme preparation from Aspergillus awamori. In contrast to pumpkin pectin obtained previously by digestion with cell-free culture medium from Bacillus polymyxa, the material prepared in the present work forms gels with 60 wt% sucrose at pH 3, although the yield is somewhat lower (14% in comparison with 22%). The main action of the enzyme complex from A. awamori is to degrade cellulose and other insoluble constituents of the plant tissue, but it also has some pectinesterase activity, which could allow degree of esterification (DE) to be manipulated by varying digestion time. The time used in this investigation (3 h) gave a DE of 53%; reduction in DE at longer times should yield pectin with a higher content of unesterified galacturonate residues, capable of binding lead and other heavy-metal cations. Some possible medicinal and food uses are suggested.


The natural polysaccharide pectin (a basic building material for cell walls of higher plants)possesses a wide spectrum of functional properties.In combination with water and some other substances,it can act as a thickener,gelling agent,stabilizer,emulsi .er,cation-binding agent,etc.(Bottger,1990).One substance having so many separate properties of technological interest makes pectin a biopolymer especially valuable for medicine and food production.Pectin is not only an effective or even necessary additive to form the structure of food products but also has medicinal bene .ts which include lowering the cholesterol level in blood,removing heavy metal ions from the body,stabilizing blood pressure,and restoring intestinal functions (Voragen,Pilnik,Thibault,Axelos,&Renart,1995).


The world consumption of pectin constantly grows and has already exceeded 20,000 tons a year.Dried lemon or orange peel and apple pomace are the main raw materials for its production.

Update 2:

And although the potential stock of these raw materials enables the main pectin producers (USA,Germany,Denmark)to plan an annual increase of pectin production of approximately 3.8%(Phillips,2000),searching for new pectin-containing raw materials is an important task of science and industry.

Update 3:

Another urgent task is to improve pectin extraction techniques from raw material.The current technology is based on acidic hydrolysis and has at least two demerits:

Update 4:

acidic extraction does not allow pectin to be extracted fully with no damage to its structure and it does not meet environmental safety due to acid usage.

Update 5:

An enzyme-hydrolytic technology seems environmentally safe and more effective in terms of pectin yield.

Update 6:

Analysis of the scientic and patent literature shows that a number of research centres have been conducting studies to develop a biotechnological method of pectin extraction but these works are of exploratory nature only,

Update 7:

they do not yet involve a wide range of researchers,and their results are far from industrial application.However,the achievements of biotechnology encourage optimism,including the problem under consideration.

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2 Answers

  • 1 decade ago
    Favorite Answer

    從南瓜提練果膠的最佳程序是使用Aspergillus awamori(一種曲黴菌)酵素調製。對照先前使用多黏芽孢桿菌為培養基以無細胞培養消化獲得的南瓜果膠,現在準備的材料可形成pH 3重量百分比為60 wt%的蔗糖膠,雖然產量比較低(14%對比22%).。從A. awamori合成的酵素主要作用方式為降解細胞膜或其它不溶的植物組職,同時有果膠酯酶作用,可藉由改變消化時間操控酯化程度。此研究的時間(3小時)可使酯化53%,更長時間的減少酯化應可產生較高;果膠甲酯酶抑製劑殘餘物含量的果膠,具有膠合鉛及其它重金屬陽離子的能力。



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  • Anonymous
    1 decade ago




    Source(s): 自己的經驗
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