chuong 5 san xuat chât phu gia từ VSV

SẢN XUẤT CÁC CHẤT PHỤ GIA TỪ VSV 1.Sản xuất acid glutamic (bột ngọt) Sản xuất acid lactic, acid citric, acid acetic Sản xuất nucleotic (chất siêu ngọt) Sản xuất dextran 1.Sản xuất sodium glutamat(bột ngọt)  Sodium glutamat tinh thể hình kim màu trắng, chất phụ gia sử dụng phổ biến làm chất điều vị cho thực phẩm chế biến  Sodium glutamat dẫn xuất acid glutamid, acid amin cần thiết có hương vị thịt, sản xuất bàng đường lên men fermentor có sụt khí với chủng VK Corynebacterium glutamicum sodium glutamat CƠ CHẾ TẠO TỔNG HỢP THỪA A.GLUTAMIC Ở VI KHUẨN Glucose co2 Purivat Citrat Citrat Oxaloacetat A-ketoglutarat Malat NH4 Fumarat Acid glutamic Succinat Màng tế bào chất Thành tế bào Acid glutamic Cơ chế gây tổng hợp thừa  Biến đổi di truyền ,gây ức chế gen chiụ trách nhiệm tổng hợp enzim xúc tác phản ứng chuyển A ketoglutarat thành succinat  Sự thay đổi tính thấm màng tê bào chất có liên quan đến sụ tạo thành acid béo màng Sự tạo thành a.béo lại lệ thuộc vào hàm lượng biotin mơi trường Trường hợp thiếu biotin làm màng tế bào cho thẩm thấu acid glutamic ngồi Do nghiên cứu nồng đọ biotin thích hợp điều quan trọng Thơng thường acid amin VSV tổng hợp với lượng vừa phải đủ để đáp ứng nhu cầu acid amin sinh tổng hợp protein cho tế bào, nhờ chúng có khả điều hòa trao đổi chất, giúp chúng tồn phát triển tự nhiên Hầu hết VSV dùng CNLM sản xuất acid amin chủng đột biến, có khả siêu tổng hợp acid amin, có nghĩa chúng VSV khả điều hòa sinh tổng hợp, nhờ tế bào VSV nhà máy hóa học tí hon , giúp người tổng hợp chất acid amin cần thiết với số lượng lớn Acis glutamic sản xuất dựa chế VSV đột biến có khả siêu tổng hợp acid glutamic lên men Fermenteur điều kiện mơi trường tối ưu Trong suốt q trình lên men Acid glutamic tổng hợp bên tế bào VSV xuất mơi rường bên ngồi với lượng lớn vượt xa nhu cầu tế bào Aspergillus niger metabolic network at 120 hours culture time (    In order to produce amino acids using microorganisms, it is important to find a microorganism with a high potential for producing amino acids One gram of natural soil contains about 100 million microorganisms From these a useful one can be picked out Once a microorganism suitable for the fermentation method has been selected, it is necessary to enhance its potential, that is, to make improvements to take full advantage of the potential of the organism Generally, microorganisms produce the 20 kinds of amino acids only in the amounts necessary to themselves They have a mechanism for regulating the quantities and qualities of enzymes to yield amino acids only in the needed amounts Therefore, it is necessary to release this regulatory mechanism in order to manufacture the target amino acid in large amounts The yield of an amino acid depends on the quantities and qualities of the enzymes The yield increases if the enzymes involved in the production of the target amino acid are present in large quantities under workable conditions, while it decreases if the enzymes are present in small quantities Suppose that a microorganism has a metabolic pathway A (a) B (b) C (c) D (a, b, and c are enzymes) In order to produce only amino acid C in large amounts, you have to enhance the actions only of enzymes a and b and to get rid of the action of enzyme c Strains are improved using various techniques to make this process possible A fermentation tank is filled with syrups/sugars derived from sugar cane, corn, and cassava, and then fermentation conditions are set so that the stirring conditions, air supply, temperature, and pH are optimum Finally, only the target amino acid is obtained from this fermented broth in high purity  Particularly Ticona, Nutrinova and high value chemicals with PVOH, Emulsions and Specialties are searching for new market applications through their development partnerships with customers The business line Specialties of Celanese Chemicals is a leading producer of TCD alcohol DM, which is primarily used for the manufacture of special polymers for resins and plastics, lacquers and coatings TCD alcohol’s properties also makes it irreplaceable as a protective coating for CDs and binding adhesives for DVDs Together with its customers, Ticona introduced the temperatureresistant and robust polymer Fortron® PPS for aircraft construction – particularly in the new wide-bodied jets The liquid crystal polymer Vectra® LCP is used by our customers in electronics and telecommunications technology, particularly in the manufacture of high-precision, robust microcomponents Additional application areas will be opened up in the future with the development of new, particularly high temperature-resistant Vectra® types    Definition of Yeast Extract  When a yeast cell is inactivated, a natural digestion process called "autolysis" starts During this process the yeast's own enzymes break down proteins and other parts of the cell This causes the release of peptides, amino acids, vitamins and other yeast cell components which, once the insoluble components have been removed, is called "Yeast Extract" The Food Chemical Codex defines Yeast Extract as follows: " Yeast Extract comprises the water soluble components of the yeast cell, the composition of which is primarily amino-acids, peptides, carbohydrates and salts Yeast Extract is produced through the hydrolysis of peptide bonds by the naturally occurring enzymes present in edible yeast or by the addition of food-grade enzymes" The two main applications of Yeast Extract   Natural aromatic ingredient for savoury foods Yeast Extracts are increasingly used for their unique taste, which is the result of amino acids and small peptides formed out of the yeast protein by the autolysis process They constitute a natural flavour ingredient, imparting delicate bouillon, meaty or cheesy notes and enhancing the flavour for a wide range of food products : soups, sauces, meat and fish preparations, savoury mixes, etc    Source of nitrogen & growth factors for culture media  Yeast Extracts are rich in nitrogen, vitamins and other growth stimulating compounds and therefore are used as an ingredient in media for the cultivation of microorganisms These organisms are for example used in the production of antibiotics, biopharmaceuticals, vitamins, organic acids, dairy cultures, probiotics, etc  Production process of Yeast Extract  The raw material is baker's or brewer's yeast The yeast cells undergo the following treatments :  Separation from the culture medium  Opening of the cells : moderate heat treatment or salt addition which allows the conservation of the enzymes  Autolysis : this step of the process is performed under mild conditions of pH and temperature ; its duration depends on the type of yeast and to what extent the proteins have to be broken down  Separation of the insoluble part such as Yeast Cell Walls from the water soluble components of yeast (mainly proteins, peptides, amino-acids, etc ) which constitute the Yeast Extract  Concentration and pasteurisation of the Yeast Extract solution  Packaging in pails, drums or totes for the liquid and paste forms (resp 50 - 65 % and 70 - 80 % dry matters)  or Spray drying and Packaging in bags, boxes, big bags for the powder forms, which can be in fine or granulated particles, or even oil coated to prevent the emission of dust   Main components of Yeast Extract  The typical composition of Yeast Extract is (expressed on dry matters basis) :  total nitrogen content : to 12 %, corresponding to a protein content of 50 to 75 %  amino nitrogen content : 3.0 to 5.2 %  total carbohydrate content : to 13 %  lipid content : none or very little  Depending upon applications, salt can be added to Yeast Extract  Regulatory status of Yeast Extract  In Europe, Yeast Extract is regulated by the European Directive 88/388 and classified as "natural flavouring preparation" In North America, the Food & Drug Administration considers Yeast Extract as natural flavour (§21 CFR 101.22) Search FAQ What are the main characteristics of Yeast BetaGlucan ? Detail FAQs  English  Français Infos légales © Eurasyp - Tous droits réservés - Design by Eurelis ... 1960,người ta biết chất 5 -IMP có hoạt tính tăng vò đặc biệt  Từ năm 1962, Nhật bắt đầu sản xuất loại bột với vò gắp trăm lần bột Đó loại nucleotic như: 5 -IMP (inosin monophosphat); 5 - GMP ( guanin... điều vị lên gần 3000 tấn/ năm Cơ chế tổng hợp IMP- AMP- GMP VSV 1.phương pháp thuỷ phân ARN nấm men enzim VSV Enzim VSV ARN ( nấm men) 5 - nucleotic Phương pháp lên men kết hợp với PP chuyển đổi... IMP hay GMP Phương pháp lên men giai dọan với 1chủng VSV đột biến  Brevibacterium ammoiagenes  Môi trườg lên men IMP 4.Phương pháp lên men giai đoạn với 2chủng VSV đột biến  Chủng đột biến Corynebacterium