Kojic acid, chemically known as 5-hydroxy-2-hydroxymethyl-1,4-pyrone, is found in the brewing of soy sauce, bean paste, and alcohol, and can be detected in many fermentation products fermented with Aspergillus. The presence of kojic acid.
On October 27, 2017, the World Health Organization's International Agency for Research on Cancer published a preliminary list of carcinogens, and kojic acid was listed in the list of three types of carcinogens.
Kojic acid alias: Kojic acid; 2-Hydroxymethyl-5-hydroxy-γ-pyrone; 5-Hydroxy-2-hydroxymethyl-4H-4-pyranone
Character: colorless prismatic crystal
Density (g/ m3, 25/4 ° C): 1.58
Melting point (oC): 153 to 154 ° C
Boiling point (oC, atmospheric pressure): 323
Solubility: Soluble in water, alcohol, acetone, slightly soluble in ether, ethyl acetate, chloroform and pyridine, insoluble in benzene.
It can be oxidized, added, reduced, and lipidated, and can also undergo complexation reaction with metal ions.
1. In the industry, starch or molasses is commonly used as a raw material for fermentation and purification. The microorganism capable of producing kojic acid is Aspergillus (including Aspergillus oryzae, Aspergillus oryzae, Aspergillus niger, Aspergillus niger, Aspergillus oryzae, Aspergillus niger, etc.).
2. Inclined species seed culture fermenter culture medium culture medium filtration
3. The filtrate is concentrated under reduced pressure → crystallized and recrystallized to dry the kojic acid.
4. It is a substance produced by the metabolism of a variety of kojimycin fungi and Aspergillus oryzae.
It should be stored in a closed package to avoid high temperature and high humidity.
1. Applied in the field of cosmetics. In human skin, tyrosine undergoes complex oxidation and polymerization with oxygen radicals under the catalysis of tyrosinase, and finally melanin is synthesized. Kojic acid can inhibit the synthesis of tyrosinase, so it can strongly inhibit the formation of melanin in the skin, and it is safe and non-toxic, and does not produce leukoplakia sequelae. Therefore, kojic acid has been formulated into lotion, mask, lotion and skin cream. It can effectively treat high-grade whitening cosmetics such as freckles, age spots, pigmentation and acne. Kojic acid at a concentration of 20 ug/ml inhibits 70-80% of the activity of various tyrosinases (or polyphenol oxidases PPO), and is generally added in cosmetics in an amount of 0.5 to 2.0%.
2. Food processing. Kojic acid can be used as a food additive to maintain the taste, aroma and texture of fresh, antiseptic and anti-oxidant foods; kojic acid also produces maltol and ethyl maltol. Experiments have shown that kojic acid can inhibit the conversion of sodium nitrite into carcinogenic nitrosamines in bacon, and the addition of kojic acid in food does not affect the raw materials. In food processing, kojic acid has a wide range of applications.
3. The field of medicine. Because kojic acid has no mutagenic effect on eukaryotic cells, it can eliminate free radicals and enhance white blood cell kinetics in human body, which is beneficial to human health. Therefore, kojic acid has been used as a raw material for cephalosporin antibiotics, and the finished drug is used for treatment. Headache, toothache and local inflammation are ideal for analgesic and anti-inflammatory effects.
4. In the agricultural field. Kojic acid can be used to produce biopesticide. Adding bio-fertilizer (dark-red liquid) made of 0.5-1.0% kojic acid, whether it is sprayed at a low concentration as a foliar fertilizer, or made into a growth-increasing agent for root application, this crop production accelerator for food and Vegetables have obvious yield-increasing effects.
5. In other fields. Kojic acid can also be used as an iron analysis reagent, a film spotting agent, and the like.
6. Kojic acid and its derivatives are used as whitening agents in the cosmetics industry, and also play a role in antiseptic and moisturizing effects. In the food industry, kojic acid is used as a food additive, as a preservative, preservative and color protectant, and as a raw material for the preparation of the flavoring agents maltol and ethyl methacrylate. It can also be used to produce intermediates for cephalosporin antibiotics. It can also be used to produce pesticides and pesticides.
7. Kojic acid and its derivatives such as acetate have certain antibacterial properties, no one-time stimulation and cumulative stimulation to the skin, and can be used as a preservative for cosmetics and food. It can absorb ultraviolet light strongly and can be used alone or in combination for various sunscreen products such as soap. It can treat and prevent the formation of skin spots such as liver spots, and the effect is obvious in the range of 1% to 2.5%. Helps maintain humidity and reduce skin wrinkles. Adding dandruff to the hair supply.
Polyphenol oxidase (PPO) present in fresh fruits and vegetables and crustaceans can cause browning. During the processing and storage of these foods, the endogenous phenolic substances are catalyzed by enzymes to form brown pigment or melanin, which affects the color of food. And produce bad flavors.
Preventing enzymatic browning of food has long been an important research topic.
The use of polyphenol oxidase inhibitors in food processing and preservation is an important means of preventing enzymatic browning of products.
Currently commonly used treatment methods are the use of sulfur dioxide or other strongly reducing sulfur compounds. Since these compounds remain in the food and release sulfur dioxide in the later process, the flavor of the food is damaged.
Kojic acid is safe and non-toxic. It is an ideal polyphenol oxidase inhibitor. It has significant effects on the color protection of fruits and vegetables and crustaceans. It can be used in combination with existing ascorbic acid and citric acid. It can be replaced or partially replaced. Traditional polyphenol oxidase inhibitors.
Fresh citron, spinach, kale, apple, banana, citrus and fresh cut flowers are currently preserved by chilling, freezing, water or light salt water, but they are often ineffective or inconvenient, so a kind of need is needed. Use a method that is easy to use.
Preservation involves the maintenance of the state of color, shape, volume, flavor, aroma, water content, etc. However, due to limitations in its own ability and amount of addition, the preservatives currently used are difficult to fully meet the requirements.
For example, ethoxyquine used for apple preservation allows a residual amount of only 1 ppm.
The study of kojic acid shows that it has anti-oxidation and antibacterial effects, is completely non-toxic and soluble in water, and can be effective in a small amount. It is an ideal material for fresh preservation of flowers, vegetables and fruits.
Coloring agents and pigments are generally used in the processing of aquatic products such as sausages, hams, and the like, and caviar. Currently, the coloring agents and coloring agents widely used are sodium nitrite.
As we all know, because nitrite can be converted into nitrosamines during food processing and digestion, a substance with strong carcinogenicity and toxicity, the world is strictly limited in its use, and the color protection effect of nitrite is also not ideal.
Other synthetic or natural pigments also have deficiencies in the color retention due to the problem of air oxidation, resulting in a shorter color retention time.
The use of kojic acid in meat products not only reduces the use of harmful chromic chromic reagents, but also has a good processing effect with vitamin C, niacinamide and other currently used color-protecting agents, and has antibacterial and anti-carcinogens. It also reduces or replaces the amount of sorbic acid and benzoic acid, and is therefore an ideal color preservative.
The application study of kojic acid shows that kojic acid can protect the color due to its antioxidant activity. The kojic acid itself has a sensitive blood red reaction with iron in myoglobin, which can partially replace the coloration of sodium nitrite.
Studies have shown that the addition of kojic acid and other compounds before the meat is smoked can inhibit the conversion of nitrite to nitrosamines, because kojic acid can selectively bind to distillates in wood and inhibit the formation of carcinogens. Adding kojic acid to bacon not only keeps the flesh color, but also prevents microbial growth.
Kojic acid has the following advantages over benzoic acid, sorbic acid and its salts, which are currently widely used in food additives:
Soluble in water, solves the problem that preservatives such as sorbic acid and benzoic acid need to be dissolved in an organic solvent before adding food;
Not used by bacteria, it has stronger and more extensive antibacterial power, while sorbic acid has weak antibacterial power and is easy to be used by bacteria. It can only be added when it is sterile;
Heat stable, can be heat sterilized together with food, and sorbic acid is easily volatilized by heat;
The pH value had no significant effect on the antibacterial activity of kojic acid, while the sorbic acid and sodium benzoate decreased with the increase of pH value;
Kojic acid is not irritating to humans and inhibits the production of carcinogens by nitrite. Sorbic acid is irritating to human skin and eyes, and can produce carcinogens when nitrate is present.
1. Kojic acid is unstable to light, heat and metal ions. Do not add high temperature when formulating. It is necessary to control the content of metal ions such as iron in the system.
2. It is preferred to add a suitable complexing agent such as EDTA and an antioxidant such as sodium sulfite in the system.