For example A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an essential micronutrient which an organism needs in small quantities for the proper functioning of its metabolism. Essential nutrients cannot be synthesized in the organism, either at all or not in sufficient quantities, and therefore must be obtained through the diet. Vitamin C can be synthesized by some species but not by others; it is not a vitamin in the first instance but is in the second. The term vitamin does not include the three other groups of essential nutrients: minerals, essential fatty acids, and essential amino acids. Most vitamins are not single molecules, but groups of related molecules called vitamers. For example, there are eight vitamers of vitamin E: four tocopherols and four tocotrienols. Some sources list fourteen vitamins, by including choline, but major health organizations list thirteen: vitamin A (as all-trans-retinol, all-trans-retinyl-esters, as well as all-trans-beta-carotene and other provitamin A carotenoids), vitamin B1 (thiamine), vitamin B2 (riboflavin), vitamin B3 (niacin), vitamin B5 (pantothenic acid), vitamin B6 (pyridoxine), vitamin B7 (biotin), vitamin B9 (folic acid or folate), vitamin B12 (cobalamins), vitamin C (ascorbic acid), vitamin D (calciferols), vitamin E (tocopherols and tocotrienols), and vitamin K (phylloquinone and menaquinones). A veterinary drug (also animal drug) refers to a drug intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease in animals. Veterinary drugs can be roughly classified into four categories: ① general disease control drugs; ② infectious disease control drugs; ③ internal and external parasitic disease control drugs; ④ (including growth-promoting drugs). Except for biochemical immune products (bacteria, vaccines, serums, antitoxins and toxoids, etc.) for the prevention and treatment of infectious diseases, and special veterinary drugs such as special parasitic drugs for livestock and poultry and growth-promoting drugs, the rest are the same as those for human use, but the dosage , dosage forms and specifications are different. It has long been widely used to control livestock and poultry diseases. Sweetening agent are food additives that impart sweetness to soft drinks. It can be divided into nutritive sweeteners and non-nutritive sweeteners according to their nutritional value; according to their sweetness, they can be divided into low-sweetness sweeteners and high-sweetness sweeteners; Divided into natural sweeteners and synthetic sweeteners. The main functions of sweetening agent in food are as follows: (1) Taste: Sweetness is one of the indicators of many foods. In order to make food and beverages taste palatable, a certain amount of sweetener needs to be added. (2) For the adjustment and enhancement of flavor, sweetness is generally required in cakes; in beverages, there is a "sugar-acid ratio" for flavor adjustment. Sweeteners allow products to achieve good flavor while retaining fresh flavor. (3) The formation of flavor, sweetness and the flavor of many foods are complementary to each other, and the flavor of many products is produced by the combination of flavor substances and sweeteners, so many foods are added with sweeteners. Cosmetics are compound mixtures made of various raw materials through reasonable deployment and processing. Cosmetics have a wide variety of raw materials with different properties. According to the raw material properties and uses of cosmetics, it can be roughly divided into two categories: matrix raw materials and auxiliary raw materials. The former is a kind of main raw material of cosmetics, which occupies a large proportion in cosmetic formulations and plays a major functional role in cosmetics. The latter is responsible for shaping, stabilizing or imparting color, fragrance and other properties to cosmetics, which are not used in cosmetic formulations, but are extremely important. Cosmetics are chemical mixtures made of natural, synthetic or extracted substances with different functions as raw materials and processed through production procedures such as heating, stirring and emulsification. API refers to active pharmaceutical ingredent, includes human growth hormone powder, pure minoxidil powder, paracetamol powder and acetylsalicylic acid powder. It indicate that the raw materials used for the production of various preparations, the active ingredients in the preparations, and various powders, crystals, extracts, etc., prepared by chemical synthesis, plant extraction or biotechnology for medicinal purposes. Substances that the patient cannot take directly. Natural active ingredient refers to active ingredients extracted from natural products, such as oyster meat powder, bulk krill oil, tomato lycopene extract powder, etc. Chemical products are the species formed from chemical reactions. During a chemical reaction reactants are transformed into products after passing through a high energy transition state. This process results in the consumption of the reactants. It can be a spontaneous reaction or mediated by catalysts which lower the energy of the transition state, and by solvents which provide the chemical environment necessary for the reaction to take place. When represented in chemical equations products are by convention drawn on the right-hand side, even in the case of reversible reactions. The properties of products such as their energies help determine several characteristics of a chemical reaction such as whether the reaction is exergonic or endergonic. Additionally the properties of a product can make it easier to extract and purify following a chemical reaction, especially if the product has a different state of matter than the reactants. Reactants are molecular materials used to create chemical reactions. The atoms aren't created or destroyed. The materials are reactive and reactants are rearranging during a chemical reaction. Here is an example of reactants: CH4 + O2. A non-example is CO2 + H2O or "energy". Food additives are substances added to food to preserve flavor or enhance taste, appearance, or other sensory qualities. Some additives have been used for centuries as part of an effort to preserve food, for example vinegar (pickling), salt (salting), smoke (smoking), sugar (crystallization), etc. This allows for longer-lasting foods such as bacon, sweets or wines. With the advent of processed foods in the second half of the twentieth century, many additives have been introduced, of both natural and artificial origin. Food additives also include substances that may be introduced to food indirectly (called "indirect additives") in the manufacturing process, through packaging, or during storage or transport.