Agricultural Research Management Information System

Home
Research Summary
Search
About Us
- ARMIS
- Brochure
Contact Us
Report
User Request
Data Input
Help
- Operation Manual
  - PDF
  - Video
- Program Area & Commodity
We have reached 37600 number of research entries at this moment.

- Logout

Research Detail

Home
Research
Detail

Rheological Study of Starches by Starch Phosphorylase Enzymes Extrated from Indigenous Plant Sources ( Corn & Potato)

Dr. Mst. Aley Nasreen
Principle Scientific Officer
Biochemistry Department, BJRI,Dhaka.

Md. Mahabub Ali
Scientific Officer
Biochemistry Department,BJRI,Dhaka.

Dr. Ferdous Ara Dilruba
Principle Scientific Officer
Printing Department , Chemistry Division, BJRI,Dhaka.

Abstract/ Executive Summary:

Starch viscosity increases over time due to high temperature. This is the general behavior of starch when it started to cook, granule of starch swells and due to high temperature evaporation take place. That’s why sample become more and more viscous over time. Generally activity of the enzyme increases with the increases of substrate and certain amount of enzyme is required for a certain concentration of substrate. If the dozes of the enzyme are more than its requirement, then it becomes a part of solute of the viscous solution and viscosity is increased instead of decreased. That’s why different concentration of substrate responded in a different manner. From the above results, it can be concluded that the 0.001% enzyme is precise for 3 to 4.25% degradation of corn starch viscosity. Enzyme concentration over this dozes can not contribute further degradation and the less concentration contribute to degrade little bit less than its appropriate doze. Starch phosphorylase from potato performs 90% reduction of viscosity by 10 minutes and initial reduction ( with in minutes) is 25 to 28%. Enzyme activity shows Michaclis Menten kinetic reaction where substrate concentration has limitation to perform enzyme activity. In this study 3.5% corn starch is maximum for enzymatic degradation. Beyond this concentration enzyme activity goes down. In case of potato starch 5% starch is the maximum concentration for 0.006% enzyme.

Keywords: Phosphorylase, corn and potato

Location: Central station, BJRI, Dhaka

Start Date: 01-01-2011

End Date: 01-07-2012

Program Area: Knowledge Management

Commodity: Potato

Objectives:

In textile industry, fabrics/yarns are subjected to size by starch. The sizing fabrics are further required to desize.Desizing procedures are performed by either chemically or enzymatically. Starch phosphorylase degrades starch to a certain level, where in three or four unit of glucose joined together.Such kind of activity of the starch phosphorylase may contribute to serve the desizing purpose more efficiently than amylase.

Methodology:

Rheological study of corn starch by applying starch phosphorylase has been studied by Brookfield digital viscometer ( Model DV – E) . Starch ( corn/potato) sample was prepared by cooking starch in 1M potassium phosphate buffer ( pH 7.00 ) by hot plate at 95 degree centigrade. When viscous starch sample was prepared, temperature was cooked down to 40 degree centigrade. Rheological measurement was carried out at 40 degree centigrade. For enzyme catalytic reaction enzyme substrate ratio was 0.25 ml : 50 ml, 0.5ml : 50ml and 1.00ml : 50ml.

Source of Information: BJRI, Dhaka, Bangladesh.

Article Link (Online Journal):

Funding Source:

1. Government

Budget:

Total Budget (Tk.) :

Achievement/Findings:

Starch phosphorylase from potato ( ptStp) shows Michaelis – Menten kinetic reaction, which has limit of maximum substrate concentration 3.25%. Enzyme ptStp 0.001% shows maximum degradation of viscosity with 3.5% corn starch and 0.006% ptStp shows maximum degradation with 5% potato starch.

Knowledge Management: Report/Proceedings