What is Tetramer technology

Tetramer technology: a technique in which MHC monomer molecules are tetramerized to increase their affinity and can be combined with multiple TCRs on T cells.

Introduction to tetramer technology

 

Since the soluble MHC monomer molecule has a low affinity with the TCR, the dissociation is fast, and the multivalent molecule can bind to multiple TCRs on one specific T cell, so that the dissociation speed is greatly slowed down. To this end, Altman et al. proposed the construction of MHC class I molecular tetramers by means of the biotin-avidin cascade amplification principle. The method uses a genetic engineering technique to add a 15 amino acid residue of Bio A substrate peptide (BSP) to a MHCI-like molecule such as the carboxy terminus of the HLA-A2 heavy chain to form a fusion protein, which is pressed in vitro. A certain proportion is incubated with beta microglobulin and specific antigenic short peptides to fold into the correct conformation and become pMHC complexes. Biotin is labeled on the lysine residue of the substrate peptide such that a fluorescein-labeled streptavidin binds to four biotinylated pMHC complexes to form a tetramer, MHC-antigen peptide tetramer and After binding of TCR on antigen-specific CFI-, antigen-specific CTLs in vivo can be quantified by flow cytometry and sorted for in vitro culture amplification and functional analysis.

 

Effect

The tetramer technology enables specific, efficient and direct quantification of antigen-specific CTI-activity assays, and can be applied to immunological research and detection, specific immunotherapy, and vaccine efficacy monitoring.

 

  • As a clinical diagnostic tool, quantitatively measure the ratio of antigen-specific CTI in peripheral blood and tissues, and perform phenotypic and functional analysis. Altman et al. have detected antigen-specific CTI in a large number of asymptomatic AIDS patients. The detection rate is as high as 2%. Zerbini et al. used tetramer technology and immunohistochemistry to detect peptide-specific CD8 CTLs in tumor tissues of hepatocellular carcinoma patients for the first time, providing broad prospects for the application of immunotherapy to MAGE antigens in HCC. In situ staining of tetramers in autoimmune diseases was first used in TCR transgenic mice. Through the quantitative detection, phenotypic and functional analysis of antigen-specific CTL, it laid the foundation for elucidating the pathogenesis of viral infectious diseases, tumors and autoimmune diseases.

 

  • For adoptive tumor immunotherapy: Mei-denbauer et al. administered a large number of Melan-A peptide-specific CTLs (42.1%) to 8 patients with refractory malignant melanoma, and found peripheral blood singles. The ratio of antigen-specific CTL in nuclear cells is determined by infusion. 01% to 0.07% rose to 2% after infusion. Moreover, these cells can survive in vivo for several weeks, have the function of secreting INF-7, and preferentially aggregate to the tumor to play a role.

 

(3) Monitoring of vaccine efficacy: In recent years, the use of antigen peptide pulse treatment as a vaccine to immunize the body to induce an effective CTL response has become a research hotspot. The efficacy of the vaccine can be monitored by tetramers constructed with homologous peptides.

 

About us

Creative Peptides is specialized in the process development and the manufacturing of bioactive peptides. We are dedicated to offering custom peptide synthesis, process development, GMP manufacturing as well as catalog products for customers in industry and research area. Here are some our products like: Glycopeptides SynthesisGhrelin PeptidesGlucagon Like PeptidesChelate Peptides, etc.

A brief talk on the Sodium Butyrate

Sodium butyrate is a chemical substance with a molecular formula of C4H7NaO2 and a molecular weight of 110.0869. The character is white or white like powder, and has special cheese rancidity like odour and hygroscopicity. The density is 0.96g/mL (25/4 C), the melting point is 250~253 C, and it is soluble in water and ethanol.

About the enzyme activity of the sodium butyrate, there are mainly four aspects: 1, buffering capacity of feed ingredients is the main factor affecting the free acid content in the stomach. The greater the buffer capacity, the more free acid can be absorbed in the stomach, which makes the free acid in the stomach decreased, the pH value in the stomach increased, and then affect the activity of protease and protein digestion and decomposition. Generally speaking, the higher the contents of protein, calcium, phosphorus and trace minerals, the higher the buffer capacity of the feed. 2, the dissociation degree is small, acidity is weak, to achieve the same acidification capacity is much larger than inorganic acid, adding cost is high; Sodium butyrate as acidifier, added in the feed diet is direct, added acid is easy to be neutralized by alkali, loss of acidification; if can not reach the small intestine, can not effectively reduce the intestinal acidification effect PH value can not inhibit the growth of harmful bacteria and promote the proliferation of beneficial bacteria. 3. Sodium butyrate is stable at low temperature and under sealed condition, but it can not be mixed with substances, dust, superheated materials and strong oxidizing agents. It is easy to dilute and agglomerate during storage or cause feed moisture. 4, the absorption and metabolism of short chain fatty acids in the colon are very strong, and butyric acid is the fastest. Because of the rapid metabolism of butyric acid, the serum half-life of butyric acid in the body is only 6 minutes. In the use of sodium butyrate as a therapeutic drug, in order to achieve effective blood concentration, the commonly used method is to use sustained-release technology, sodium butyrate is coated into tablets, so that butyric acid can reach the colon without previously being absorbed and metabolized by the small intestine.

For example. Breast cancer is a common malignant tumor, which seriously affects the health of women. In recent years, the incidence of breast cancer in the world is increasing year by year and the age is gradually younger [. Sodium butyrate is a sodium salt of short-chain fatty acid butyric acid. It mainly changes chromatin structure by changing the acetylation degree of histone and participates in the expression of many genes. Sodium butyrate can be produced by anaerobic bacteria after digestion and fermentation of carbohydrates and proteins in the above foods. Sodium butyrate accounts for a large proportion of energy sources in colon epithelial cells, which stimulates the release of colon peptides or growth factors, regulates the blood supply of colon mucosa and promotes the growth of colon epithelial cells. Epithelial cell proliferation, but some reports have shown that sodium butyrate can also inhibit the proliferation of tumor cells and induce cell senescence and apoptosis.

The industrial enzyme production of the Sodium Butyrate is a complex access, so for more information, you can click here to visit our website.

A brief talk on the invertase

Invertase, also known as sucrase or beta-D-fructofuran glucosidase, is the key enzyme in sugar metabolism in organisms. It catalyzes the following reactions in sucrose metabolism: sucrose + H2O fructose + glucose. Sucrose is the main product of photosynthesis in higher plants. It is an important factor in carbon transport, sink metabolism, sugar accumulation, fruit quality formation, and also a regulator of cell metabolism. Sucrose may play a role by influencing gene expression. Therefore, transaminase, which is closely related to sucrose metabolism and accumulation, has become one of the hotspots of papain enzyme, biochemical, physiological, ecological and molecular biology research in recent years.

Invertases are highly polymorphic, including acid invertases (AI), neutral invertases (NI) and alkaline invertases. Many reports regard neutral invertase and alkaline invertase as the same invertase. Acidic invertase mainly exists in enzyme urease or bound to the cell wall, and its optimum pH is 3.0-5.0; neutral and alkaline enzymes are located in the cytoplasm, and the optimum pH is about 7.0. The molecular weight of the transformed enzyme is 50~80 kD, which is monomer or two dimer. There are vacuolar invertase expression in reproductive organs. Studies on cultivated tomatoes, wild tomatoes and transgenic tomatoes showed that the expression of vacuolar invertase determined the soluble sugar content of the fruit at the late ripening stage. In situ hybridization showed that cell wall invertase might exist in serrapeptase enzyme. Tissue and sub-tissue localization of invertase showed that high activity of invertase in cell wall was associated with rapid tissue growth, while high activity of vacuolar invertase was often associated with fruit development or rapid expansion of storage organs. This phenomenon was found in seedlings, young leaves, young roots and young fruits. Fast growing tissue always has a high level of AI activity, while NI activity is much lower than AI activity. In melon, the increase of AI activity provides hexose as a carbon source for rapid tissue growth. Invertase from melon fruits hydrolyzes sucrose to glucose and fructose to maintain osmotic pressure of cells.

Invertase is related to fruit development, maturation and sugar accumulation. As fruit ripening and sucrose accumulation, AI activity decreased. This change has been found in netted melon, sugar beet and other plants. Schaffer et al. concluded that the decrease of soluble AI (in vacuole) activity was a primary condition for sucrose storage by comparing sweet and non-sweet melon varieties. Sucrose hydrolase activity (insoluble AI and soluble AI, NI) of peach was higher in young fruit stage. Sucrose accumulation and hydrolytic enzyme activity decreased with fruit development. As a cytosolic enzyme, NI has lower AI level in mature tissues, so NI is more important for sucrose hydrolysis. NI was found to regulate sucrose metabolism in mature tissues of sugarcane, beet, citrus and carrot, but not in immature tissues. The activity of NI in immature tissues of Melon reticulata was higher than that of AI. With fruit development, the decreasing trend was the same as that of AI. Gao et al. thought that the function of NI in sucrose metabolism of Melon fruits might be different from other sucrose storage papaya papain

Sucrose metabolism in higher plants is a complex process. The distribution of key invertases in plants and their changes in sucrose accumulation have been studied. It is a research direction to study the direct effect of invertase genes on sugar accumulation in fruit by molecular biological means. In addition, environmental stress and invertase regulation have also been studied. The study provides a good foundation, but the adversity area involved and the accumulation of information are very limited. Because most of the growth cycles of plants and crops are in adverse ecological conditions, it is still of great practical significance to study the polymorphism expression and physiological regulation of invertase under various stresses.

How does DNA vaccine work?

DNA vaccines are a type of nucleic acid vaccines, which are also called genetic vaccines. The plasmid vector containing the encoded protein gene sequence is introduced into the host by intramuscular injection or microprojectile bombardment, and the antigenic protein is expressed by the host cell, thereby inducing the host cell to generate an immune response to the antigen protein to prevent and treat the disease.

Nucleic acid vaccines are developed by modern biotechnology means, including immunology, biochemistry, molecular biology, etc. They are divided into DNA vaccines and RNA vaccines. At present, the research on nucleic acid vaccine is mainly based on DNA vaccine. DNA vaccines are also known as naked vaccines. After the DNA vaccine is introduced into the host, it is taken up by the cells, and the protein antigen of the pathogen is expressed in the cells, and the cellular immunity and humoral immunity are stimulated by a series of reactions.

The immune mechanism of the nucleic acid vaccine is illustrated as follows:

  1. Nucleic acid vaccine is a nucleic acid-mediated immunization vaccine developed in recent years.

The essence is that the eukaryotic expression vector containing the pathogen antigen gene can be taken up by the body cells and express the antigenic protein of the pathogen when it is introduced into the body, thereby inducing the body’s immune response to the protein. A systemic or local immune response can be triggered as the route and location of the introduction differs. In a systemic immune response, both humoral and cellular immunity can be induced.

  1. Nucleic acid vaccine can trigger a comprehensive immune response

When a protective antigen gene with a highly expressed regulatory sequence is introduced into an animal’s somatic cell, only a small amount is taken up by the cell and enters the nucleus. Under the control of the promoter on the vector, the antigen gene mRNA is transcribed, and the latter enters the cytoplasm and is translated. Corresponding antigenic protein.

 

  1. Nucleic acid vaccine can also induce local immune response and immune memory

If a gold granule coated with a nucleic acid vaccine is introduced into the mucosa by a gene gun, it may be taken up and expressed by lymphocytes or mucosal epithelial cells in the mucosa-associated lymphoid tissue under the mucosa, and the produced antigen protein is easily localized by the antigen. The presenting cells (APC) recognize, ingest, process and present to TH cells, further activating B cells in local lymphoid follicles to differentiate into plasma cells and Bm cells, which produce immune memory, the former can synthesize IgA, and the IgA monomer has a J chain linked together. When passing through the mucosa, the secretory sheet produced by the mucosal epithelial cells is linked to the dimeric IgA, and the stable secretory type IgA is discharged together with the mucosal secretion, distributed on the mucosal surface, in the mucosal part. It plays a very important role in defense against infection.

So, here comes with the question: how does the DNA vaccine work?

 

The mechanism of action and influencing factors of DNA vaccine

The DNA vaccine is a new vaccine in 1990, also known as a nucleic acid vaccine. The DNA vaccine clones a foreign gene encoding an antigenic protein into a eukaryotic plasmid expression vector, introduces the recombinant plasmid directly into the animal cell, and allows the foreign gene to express the antigenic protein in the animal through the transcriptional system of the host cell. Thereby inducing the host to produce an immune response to the antigenic protein for the purpose of preventing and treating the disease.

DNA vaccine can stimulate the body-specific immune response, has a long immunization period, has the advantages of low production cost, easy mass production and preservation, and is a new generation vaccine with application prospects. However, compared with traditional vaccines, the immune response stimulated by DNA vaccines is relatively weak, which is not enough to cause sufficient immune protection, especially for humans and large animals. Therefore, studying the mechanism of action and influencing factors of DNA vaccines is crucial for the development and application of the vaccine.

The mechanism of action of DNA vaccine

Current studies have shown that the immune response induced by DNA vaccines includes both humoral immunity (specific antibodies) and cellular immune responses with longer memory times and cell killing power. It is generally considered that after the nucleic acid vaccine is introduced into the body, it is taken up by surrounding tissue cells, antigen-presenting cells or other inflammatory cells. The plasmid DNA molecules taken up by tissue cells such as muscle cells are then transcribed into mRNA in the nucleus and then transferred to the cytoplasm for translation into antigenic protein molecules. An antigenic protein molecule secreting cells released into the interstitial space is captured by an antigen-presenting cell, processed into an antigen peptide, and presented to the T cell to initiate an immune response. APCs in peripheral lymphoid organs directly ingest nucleic acid vaccines, express antigens and present them to T cells, triggering an immune response. Dendritic cells are the most important antigen-presenting cells in the process of nucleic acid immunization, while B cells do not participate in antigen presentation during nucleic acid immunization. After eliciting an immune response, the cytotoxic T cell response recognizes and kills the muscle cells expressing the foreign antigen, causing the myocyte to dissolve and release the intracellular antigen, and APC directly acquires the antigen from the injection site, and then initiates the subsequent immune response. The combined action of several pathways allows DNA vaccines to stimulate T lymphocytes via the histocompatibility complex MHC I and MHC II pathways, as well as activate B lymphocytes. Tissue cells such as muscle cells may play a role in storing plasmids and releasing them during the immunization process.

DNA vaccines are a relatively new development in the field of vaccinology, and this approach is now moving toward rational DNA vaccine design. Strategies include optimizing vector backbones, transgenic sequences, co-expression stimuli, introduction systems for vectors, and targeting vectors for obtaining appropriate immunostimulation. Another consideration is the use of design methods to optimize gene expression. Since been discovered, DNA vaccine has entered a new stage after more than 10 years of development. Due to its ease of use and wide application, it has become a trend in the development of new vaccines in the 21st century. Although the DNA vaccine itself is relatively less immunogenic, recent studies have shown that DNA vaccines are primed, enhanced with recombinant viral vectors or recombinant protein vaccines, and are extremely effective in activating the immune system and inducing a strong immune response. This prime-boost immunization program has been used as a new vaccine model. The effects of DNA vaccines are determined by factors such as the plasmid itself, vaccine adjuvants, and immunization protocols, and their interactions. There are many strategies for enhancing the immunological or therapeutic effects of DNA vaccines, including optimization of antigen expression, selection of immune pathways, delivery vehicles, and selection of adjuvants.

A brief talk on the nucleic acid vaccine

Nucleic acid vaccine is to clone an exogenous gene encoding a specific antigen into an eukaryotic expression plasmid, and then inoculate the recombinant plasmid into the body, so that the exogenous gene can be expressed in the host body, producing an antigen to stimulate the immune system and induce specific immune response. Nucleic acid vaccine is the third generation vaccine after inactivated vaccine, Viral Vaccine and recombinant protein vaccine.

In May 1994, the World Health Organization (WHO) Global Vaccine and Immunoregulation and other three agencies jointly held a conference on nucleic acid vaccines in Geneva. The participants fully affirmed the potential application value of nucleic acid vaccines. Nucleic acid vaccines have many prominent advantages:

(1) they can express natural protein antigens, form correct folding and post-translational glycosylation modifications, what is called the vaccine delivery and present them to the host immune system similar to the natural infection process, closer to the natural molecular form, including configuration-related sites, so that they can induce more effective immune response.

(2) It can induce omnidirectional immunity, including cellular immunity and humoral immunity. After immunization with nucleic acid vaccine, specific antibodies with high titers and CTL reaction can be detected.

(3) Production is simple, cost is low, stability is good and storage is convenient. Nucleic acid vaccine only involves gene operation. It does not need radiation protection facilities like the first generation attenuated live vaccine, nor does it need cell culture, protein purification and other complex processes like the second generation Recombinant Protein Vaccine. The nucleic acid vaccine is only a gene fragment of an antigen of the pathogen, not the gene of the whole pathogen, and the plasmid is used as a vector, and no infectious factors are involved. Immunization is sustained and long-term immunity can be obtained by one vaccination, which avoids the tedious need to strengthen immunization for many times, such as inactivated vaccine and recombinant subunit vaccine.

The cross-protection of homologous and heterologous strains, using conservative DNA sequences between homologous and different strains as nucleic acid vaccine, can break through the limitation of geographical strains, which has been confirmed in influenza A virus. Therefore, nucleic acid vaccines have shown great potential in the prevention of infectious diseases such as bacteria, viruses and parasites. It has been proved that DNA vaccine has both safety of recombinant subunit vaccine and high efficacy of attenuated live vaccine in inducing comprehensive immune response. The research of nucleic acid vaccine is becoming a new direction of development.

In 1990, Wolff. first proposed the technique of naked DNA. They tried to make mouse muscle cells absorb plasmid DNA to produce new proteins by chemical methods. The control group was injected with DNA without any chemical reagents. Unexpectedly, the muscle cells of the control group absorbed the exposed plasmid DNA and expressed exogenous proteins at a high level. Williams found that the protein expressed in vivo could induce immune response in 1991. Tang confirmed Williams’discovery in 1992. In 1993, Ulmer confirmed that the recombinant plasmid encoding influenza A virus nucleoprotein could effectively protect mice against different subtypes of influenza virus. Subsequently, a large number of animal experiments showed that under suitable conditions, DNA vaccination can produce both cellular and humoral immunity.

At present, there are two expression vectors, plasmid DNA and RNA. Using RNA as vaccine can solve some safety problems related to DNA vaccine. Because of the short existence time of the RNA, it will not integrate into the chromosomal DNA, so it will not cause insertion mutation. It has been proved that direct injection of RNA into mouse skeletal muscle results in transient expression of reported genes in vivo. Martinod injected the NP gene encapsulated by liposome directly into the body subcutaneously and intravenously, effectively stimulated the specific cytotoxic T cell effect of anti-virus, and the NP protein produced by the translation of the RNA could be processed into different antigenic polypeptides according to the corresponding MHC type I molecule. It should be emphasized that RNA cannot replace DNA vaccine, it does not have all the advantages of DNA.        

Its expression is short and does not induce long-term immunity. Inorganic adjuvant will play a important role in this access. In addition, RNA is not as stable as DNA, and its production, storage and transportation costs are higher than DNA. Plasmid DNA is more commonly used because of its stable nature, easy extraction and preservation, long expression time in vivo and strong immune response. Unlike inactivated vaccines, attenuated live vaccines and recombinant genetic engineering vaccines, the chemical properties of commonly used nucleic acid vaccines are double-stranded cyclic DNA.

Although the occurrence and development of nucleic acid vaccine is not long, it has made many gratifying achievements. It has many advantages, such as simple operation, high level of protective humoral and cellular immunity induced by the organism at the same time, and is safe and effective. It has broad application prospects in anti-pathogenic infections and anti-cancer. It is attracting strong interest of scholars in various fields. However, in the development of nucleic acid vaccines, some potential problems cannot be ignored. There are still many imperfections in the development of nucleic acid vaccines. There is still a lot of work to be done in practical application.

A brief talk on the transport protein

Transport protein are a large class of membrane proteins that mediate chemicals and signal exchange inside and outside the biofilm. Lipid bilayers form a hydrophobic barrier around cells or organelles that isolates them from their surroundings. Although some small molecules can penetrate directly through the membrane, most hydrophilic compounds, such as sugars, amino acids, ions, drugs, etc., require the help of specific transport protein to pass through the hydrophobic barrier. Therefore, transport protein play an important role in a wide range of cellular activities such as nutrient uptake, metabolite release, TCR repertoire and signal transduction.

Transport protein have many transport proteins in the inner membrane of chloroplasts, called transport protein. Their function is to selectively transport molecules into and out of chloroplasts. Transport of all transport protein in the chloroplast inner membrane is driven by concentration gradients rather than active transport. This is not only different from the transport proteins in the cytoplasmic membrane, but also different from the transport system in the mitochondrial inner membrane. There are also active transport proteins in the mitochondrial inner membrane and the scFv repertoire. An important transport mechanism of chloroplast transport protein is the exchange of “Pi transport protein” through which Pi and phosphoglycerin can be transported simultaneously. Chloroplast photosynthesis requires a large amount of inorganic phosphorus, and a large amount of intermediate 3-phosphoglyceric acid (3PGAL) is released. The phosphoric acid exchange carrier protein in the chloroplast inner membrane can transfer the inorganic Pi in the cytoplasmic membrane to the chloroplast matrix through the exchange and release the 3PGAL formed in the chloroplast matrix into the cytoplasm. Phosphate exchange transport protein are the most abundant proteins in the inner membrane of chloroplasts, accounting for about 12% of the total inner membrane proteins.

On June 5, 2014, Tsinghua University announced that the crystal structure of human glucose transporter GLUT1 was first analyzed by Professor Yan Ning’s research team of Tsinghua University Medical College in the world, and its working mechanism and pathogenesis of related diseases were preliminarily revealed. This research achievement has been praised as a “milestone” major scientific achievement by the international academic circles. Yan Ning’s research team started the GLUT1 study in 2009. In the past five years, they have made bold innovations, made important breakthroughs in research ideas and experimental techniques, and established China’s leading edge in the forefront of structural biology. Human transmembrane transport of glucose has been studied for about 100 years. GLUT1, a glucose-transporting protein, was first isolated from red blood cells in 1977, but its gene sequence was identified in 1985. Since then, obtaining the three-dimensional structure of GLUT1 to truly understand its transport mechanism has become the frontier and the most difficult research hotspot in this field. In the past few decades, many of the world’s top laboratories in the United States, Japan, Germany, the United Kingdom and other countries have been or are trying to tackle this problem, but have never succeeded.

It is reported that this achievement is not only a major breakthrough in the study of peptide repertoire in the glucose transport protein , but also provides an important molecular basis for understanding the transport mechanism of other glucose transport protein with important physiological functions just like the bound antibodies, revealing the process of life-sustaining substances entering the cell membrane and transporting them into the human body. It is of great guiding significance to understand the life process step by step. Professor Lu Bai of Tsinghua University Medical College said, “The significance of this achievement lies in two aspects. First, from the point of view of scientific research, the first reveals the structure of human transport protein, which can help people understand the most basic process of molecular transport in life science. From a clinical point of view, it is helpful to understand the pathogenesis of epilepsy, cancer and diabetes in young children, and can be used as a potential target for drug research and development. After the results were published in the Journal Nature, 2012 Nobel Prize laureate Bryan Klebica said, “The structure of mammalian membrane proteins is much more difficult than that of bacterial homologous proteins because of the anti-idiotypic antibodies, so the structure of mammalian membrane proteins obtained so far is very few. But to develop drugs for human diseases, it is very important to obtain the structure of human transport protein. Structural analysis of GLUT1 itself is a challenging and risky task, so it is a great achievement. As for the production of anti idiotypic antibodies Ronald Cabeck, a professor at the University of California, Los Angeles and a specialist in transporter protein research, said, “Academia has studied the structure of GLUT1 for half a century, and Yanning was the first person in the world to obtain the crystal structure of GLUT1. To some extent, she has overcome the past 50 years to engage in it.” All the scientists involved in the study. This is also the first human transporter structure ever obtained and represents an important technological breakthrough just like the Fab repertoire. The results are self-evident for the study of cancer and diabetes. Harvey Laudish, a professor at the Massachusetts Institute of Technology and a member of the American Academy of Sciences and the cloning of GLUT1 gene, said, “This is a very important achievement that has finally revealed clearly the 12 transmembrane structures and transport mechanisms of GLUT1, which has been speculated for 30 years since the cloning of the gene.

An introduction of Indian Bread Extract

Background and overview

The dried sclerotium of Poria cocos (Schw.) Wolf, which is parasitic on the rhizome of Pinus koraiensis or Pinus massoniana, is buried in the soil under 20~30 cm. The inner part of the nucleus is white, the outer part is suede, and the sclerotium with pine root is scorpion. A fungus belonging to the genus Polyporaceae, which is a dry epidermis that is peeled off when the sclerotium is processed. As a traditional medicine and food homologous item, it has a long history of application, its sweet, light, and flat, has the effect of diminishing water, spleen and spleen, often used for edema, urinary sputum, spleen and spleen, then diarrhea, restlessness, horror and insomnia.

 

The main chemical components of the extract are: polysaccharides, triterpenoids, fatty acids, sterols, enzymes, and the like. Since the 1970s, many scholars have studied the chemical constituents and biological activities of medlar, and found that a large number of triterpenoids contained therein have immunomodulatory, antitumor, anti-inflammatory antagonistic aldosterone, and induced leukemia cell line HL-60. Very good pharmacological activity. Modern pharmacological studies have shown that triterpenoids and polysaccharides in alfalfa extract have a variety of physiological activities as natural active substances, such as improving immunity, antibacterial, hypoglycemic, anti-tumor and the like. The whitening effect of cockroaches, such as the inhibitory effect of triterpenoids on tyrosinase in alfalfa extracts, has also been reported. The sputum has the effects of turbidity, turbidity, stagnation, spleen and so on, and it is reflected in many classic traditional medical works. It is worth noting that modern science and technology research on the biological activity of alfalfa extract mainly focuses on improving immunity, anti-tumor, anti-inflammatory, etc., which may be caused by the difference in the theoretical system of medicine. Of course, the traditional effects of sputum, such as urinary system, soothing (anti-convulsion), etc., are also supported by some modern research results.

 

Ingredient

 

The extracts are rich in chemical components, including polysaccharides, triterpenoids, steroids, proteins, minerals, etc. Among them, polysaccharides and triterpenoids are abundant and active, so most of them are The separation and identification studies are also aimed at these two types of components.

 

Polysaccharide compound

Lycium barbarum polysaccharide is a fungal polysaccharide and is a symbolic component of earthworms, accounting for 70% to 90% of dry weight. Due to the complexity of the composition and structure of the polysaccharide, the polysaccharides isolated from the sputum by different researchers vary from molecular weight to composition to structure. According to the composition of Lycium barbarum polysaccharides, they can be divided into two categories: one is a homopolysaccharide of dextran, which is mainly linked by β-(1→3) glycosidic bonds, which contains a small amount of (1→6) linked glucan. Branching, also known as Pachyma, is the majority of this type of polysaccharide. Derivatization of ubiquitin can improve water solubility and biological activity, such as carboxymethylation, hydroxyethylation, hydroxypropylation, sulfation, etc., among which the biological activity of carboxymethylated derivatives (CMP) obvious. Another type of polysaccharide is a heteropolysaccharide composed of fructose, galactose, glucose, mannose or the like.

 

Triterpenoid

Triterpenoids are another major active ingredient in alfalfa. Although the content is far less than that of polysaccharides, it also plays an important role in the biological activity of alfalfa. To date, dozens of triterpenoids have been isolated from sputum, including citric acid and ibrate. The structure of the triterpenoids is basically derived from lanosterane.

 

other

There are many other compounds in the sputum, such as sterols, fatty acids, gums, lecithins, proteins, etc., but their number and variety are few, and lack of obvious variety specificity, so there is less in-depth study of these compounds.

 

 

About us

As a global Contract Research Organization (CRO), Alfa Chemistry has served the pharmaceutical and biotechnology industries for eight years. We offers an extensive catalog of Finger Citron Extract, Flos Caryophyllata Extract, Sword Bean, Lophatherum gracile in a wide range of applications.