CN1266855A

CN1266855A - Process for preparing chitosan

Info

Publication number: CN1266855A
Application number: CN 99119390
Authority: CN
Inventors: 渠荣遴; 杜荣骞; 于明喜; 李德森; 纪明耀; 张玉树
Original assignee: Dagang Oilfield Group Tuanbowa Development Co; Tianjin Genetics Society; Tianjin University
Current assignee: Dagang Oilfield Group Tuanbowa Development Co; Tianjin Genetics Society; Tianjin University
Priority date: 1999-09-15
Filing date: 1999-09-15
Publication date: 2000-09-20
Anticipated expiration: 2019-09-15
Also published as: CN1094944C

Abstract

A process for preparing chitosan using the fly maggot, fly pupa and fly pupa shell as raw material includes washing, crushing, removing protein, fat, mouth part and viscus, decolouring, decalcifying, washing to obtain chitin, reaction with solution of sodium hydroxide, maintaining temp at 65-140 deg.C for 1-10 hr, filtering or centrifugal separation, washing and baking. Its advantages are low contents of ash, heavy metals and calcium, simple process and low cost.

Description

A kind of preparation method of chitosan

The invention belongs to a kind of preparation method of chitosan.

The production of chitosan is main raw material with shrimp, crab shell at present, owing to be subjected to the restriction of raw material type, the content of chitosan ash content, heavy metal and calcium of preparation is higher, product be difficult to be directly used in the field that medicine, fine chemistry industry etc. have relatively high expectations to chitosan mass (Chinese patent, CN1085564).Also having with the silkworm chrysalis skin is raw material (" preparation of pupa cot glycan and as the research of enzyme immobilization carrier "; " research and development of natural products " 97; 9 (2): reach 48～52) or with " puparium " preparation method that " maggot skin " is the feedstock production chitosan (produce the processing condition of chitosan by five kinds of raw materials "; " fine chemistry industry " 96; 13 (4): 54～57); but preparation process is long; repeatedly change alkaline solution; complex process; the cost height; be unfavorable for large-scale production, also not with maggot skin and maggot mouthpart, the isolating report of internal organs.

The purpose of this patent is that employing housefly maggot, housefly fly pupa and tame fly puparium are raw material, improves preparation technology, overcomes the shortcoming of existing technology of preparing.

Raw materials such as puparium after housefly maggot, housefly pupa, housefly sprouted wings clean with substratum and are separated, and prevent from substratum is brought in the reactor.Adopted the high speed disintegrator break process 20～60 seconds, after filtration or centrifugal remove most of protein slurry after, again raw materials such as maggot skin are put into concentration less than 6% sodium hydroxide solution, 80～100 ℃ of heating 3～15 hours, continue to remove protein and fat.After reactant is emitted from still; remove mouthpart and internal organs by stirring and segregation; filter or centrifugal after product is washed to neutrality; adding concentration was at room temperature decoloured 2～6 hours less than 0.6% potassium permanganate solution; put into 0.3%～3% oxalic acid demanganize 1～5 hour once more behind the edulcoration; be washed to neutrality again; add 0.5～2.0N hydrochloric acid (analytical pure) decalcification 3～15 hours; put into reactor after the cleaning; adding concentration is 35～65% sodium hydroxide solution; be incubated 1～10 hour and carry out deacetylated reaction under 65 ℃～140 ℃ conditions, the product that obtains after reaction is finished is cleaned with pure water; chitosan of the present invention is made in oven dry.According to the difference of raw material type, raw material that has such as puparium can not removed the needs of mouthpart and internal organs without fragmentation yet, but the main raw material housefly maggot of production usefulness must be through fragmentation, and note removing mouthpart and internal organs, to improve the quality of product.

Because it is that raw material is produced chitosan that the present invention adopts housefly maggot, housefly pupa and tame fly puparium, this preparation method makes low ash content under better simply processing condition, low ca content, low-heavy metal content and in or low viscous chitosan, wherein ash content is lower than 0.5%, and calcium contents is lower than 200 μ g/g, and heavy metal (in Pb) content is lower than 2 μ g/g, viscosity (1% solution of 1%HAc, 20 ℃) is 10～200mpas.

Embodiment:

Get the housefly maggot 40Kg behind the isolation medium, put into high speed disintegrator with its fragmentation after cleaning, after with industrial centrifugal machine the maggot slurry being thrown away, the maggot skin is cleaned, put into reactor again with clear water.In reactor, add 50 liters of 5% sodium hydroxide solutions, be warming up to 100 ℃, be incubated after 8 hours, mixture in the reactor is emitted, through stir and filter with 100 eye mesh screens remove fly maggot mouthpart and internal organ after, remove alkali lye, the product of water flushing removal alkali lye is till go out liquid and be neutrality.The product of cleaning is put into 0.5% potassium permanganate solution decolouring 5 hours, take out and put into 1% oxalic acid demanganize 1 hour after cleaning once more, put into 2% hydrochloric acid decalcification 12 hours again after cleaning with pure water.Put into 50% sodium hydroxide solution after product after the decalcification washed, be warming up to 100 ℃, be incubated 1 hour and carry out deacetylated reaction, drench alkali lye after reaction is finished, with product clean, oven dry makes the chitosan of the present invention's preparation.

Claims

1. the preparation method of a chitosan; the invention is characterized in the employing housefly maggot; the puparium that housefly fly pupa and housefly stay after sprouting wings is a raw material; separate with substratum through cleaning; after 20～60 seconds after-filtration of break process or centrifugal treating are removed most of protein slurry in high speed disintegrator; raw materials such as maggot skin being put into concentration heated 3～15 hours under 80 ℃～100 ℃ conditions of reactor less than 6% sodium hydroxide solution again; continue to remove protein and fat; reactant is emitted the back and is removed mouthpart and internal organs by stirring and segregation from still; filter or centrifugal after product is washed to neutrality; adding concentration was at room temperature decoloured 2～6 hours less than 0.6% potassium permanganate solution; put into 0.3%～3% oxalic acid solution demanganize after cleaning once more 1～5 hour; be washed to neutrality then; the analytical pure hydrochloric acid decalcification of adding 0.5～2.0N 3～15 hours; put into reactor after the cleaning and carry out deacetylated reaction, reaction is finished after pure water is cleaned and chitosan of the present invention is made in oven dry.

2. deacetylated reaction according to claim 1 is characterized in that this reaction is that to add concentration in reactor be 35～65% sodium hydroxide solution, is heated to 65 ℃～140 ℃, is incubated to carry out under the condition in 1～10 hour.