1. Malondialdehyde (MDA) is one of the commonly used indicators to measure the degree of oxidative stress and can reflect the degree of plant membrane lipid peroxidation. In living organisms, free radicals act on lipids to undergo a peroxidation reaction. The end product of oxidation is malondialdehyde, which can cause cross-linking and polymerization of life macromolecules such as proteins and nucleic acids, and is cytotoxic. Malondialdehyde (MDA), the end product of lipid oxidation, affects mitochondrial respiratory chain complexes and key enzyme activities in mitochondria in vitro. MDA is one of the most important products of membrane lipid peroxidation, and its production can also aggravate membrane damage. Therefore, MDA content is a commonly used indicator in the study of plant aging physiology and resistance physiology. MDA can be used to understand the degree of membrane lipid peroxidation and indirectly measure the degree of damage to the membrane system and the stress resistance of plants.
2. Reducing sugar refers to sugars with reducing properties. Among sugars, both monosaccharides containing free aldehyde or ketone groups and disaccharides containing free aldehyde groups are reducing. Reducing sugars include glucose, fructose, galactose, lactose, maltose, etc. Soluble sugar is an important osmotic adjustment substance in plants. Adverse environments such as water stress, salt stress, and cold stress will cause significant changes in the soluble sugar content in plants.
3. Chlorophyll is the main pigment for photosynthesis in plants. It is a family of lipid-containing pigments located in the thylakoid membrane. Chlorophyll absorbs most of the red and violet light but reflects green light, so chlorophyll appears green, and it plays a central role in light absorption during photosynthesis. The level of chlorophyll content directly affects the photosynthetic ability of plant leaves. Leaf chlorosis is a common phenomenon that occurs after plants are poisoned by heavy metals. Hg can cause damage to chloroplasts, the site of photosynthesis in plants.
4. Glutathione (GSH) is a tripeptide containing γ-amide bond and sulfhydryl group, composed of glutamic acid, cysteine ??and glycine. Glutathione can help maintain normal immune system function, and has antioxidant and integrated detoxification effects. The sulfhydryl group on cysteine ??is its active group (so it is often abbreviated as G-SH) and is easily combined with certain drugs. (such as paracetamol), toxins (such as free radicals, iodoacetic acid, mustard gas, heavy metals such as lead, mercury, arsenic, etc.), and have an integrated detoxification effect.
5. Peroxidase is a type of oxidoreductase produced by microorganisms or plants. They can catalyze many reactions. Peroxidase is an enzyme that uses hydrogen peroxide as an electron acceptor to catalyze the oxidation of substrates. Mainly found in peroxisomes of cells, with iron porphyrin as a prosthetic group, it can catalyze the oxidation of phenolic and amine compounds by hydrogen peroxide, and has the ability to eliminate superoxide 6. Superoxide Dismutase (SOD) , also known as liver protein. SOD is an active substance derived from living organisms. It is an active protease containing metal elements and can eliminate harmful substances produced by organisms during their metabolism. SOD has special physiological activity and is the primary substance that scavenges free radicals in organisms. The level of SOD in living organisms is an intuitive indicator of aging and death.
7. Catalase is an enzyme that catalyzes the decomposition of hydrogen peroxide into oxygen and water, so that H2O2 does not react with O2 under the action of iron chelates to form very harmful -OH, which exists in Cellular peroxides in the body.
8. Soluble protein: refers to proteins that can be dissolved in water or other solvents in the form of small molecules. It is usually used as an important indicator in experiments on plant physiology, microorganisms, and food processing. For example, soluble protein is one of the important indicators of plant cold resistance. Soluble proteins are important osmotic regulating substances and nutrients. Their increase and accumulation can improve the water retention capacity of cells and protect the vital materials and biofilms of cells. Therefore, they are often used as one of the indicators for screening resistance.
9. Non-protein thiol (NPT) content: Non-protein thiol (NPT) is one of the main substances in the heavy metal detoxification mechanism of plants. It is mainly composed of substances rich in sulfhydryl groups. Including phytochelates (PCs), glutathione (GSH), γ-glutamylcysteine ??(γ-EC), cysteine, etc. Sulfhydryl groups can combine with Hg ions and reduce free Hg in cells to achieve the purpose of detoxification. Therefore, the NPT content in different parts of the tung tree can reflect the tolerance of the tung tree to Hg.
10. Gel chromatography (gel chromatography), also called molecular sieve chromatography, means that when the mixture passes through the gel chromatography column with the mobile phase, each component is separated according to its molecular size. Separation technology. Gel chromatography has been widely used for the separation and purification of enzymes, proteins, amino acids, polysaccharides, hormones, alkaloids and other substances.
11. Electrophoresis: Under the action of an electric field, charged particles move toward an electrode with the opposite electrical property, which is called electrophoresis (EP). The technology that utilizes the different moving speeds of charged particles in an electric field to achieve separation is called electrophoresis technology.
12. Two-dimensional electrophoresis is a combination of isoelectric focusing electrophoresis and SDS-PAGE. That is, isoelectric focusing electrophoresis (separation according to pI) is performed first, and then SDS-PAGE (separation according to pI) is performed. molecular size), the electrophoresis pattern obtained after staining is a two-dimensional distribution of protein patterns. Electrophoresis technology was used to isolate and purify proteins related to mercury stress in tung flower seedlings, and the functions and properties of these proteins were further studied and analyzed. The dual effects of hydrogen and the toxicity of phenols and amines. 13. Leaf mercury continuous separation technology: separate the mercury content in the leaves into three parts: leaf surface mercury, leaf cuticle mercury and leaf tissue mercury. Measure these three parts separately. The expected result may be: tissue mercury > cuticle mercury > Surface mercury, which may be related to the protein content of various parts of the leaves.