Research on the application of natamycin, the late

Study on the application of a new preservative natamycin (Part 2)

3.2 extraction and separation of natamycin

natamycin is insoluble in water, so it is crystalline in the fermentation broth. Natamycin crystal has needle type, disc type and so on. They are all formed in the fermentation process, and the diameter is generally 0.5~20? Zi M

natamycin was initially extracted with water-soluble or partially water-soluble solvents

maldonado et al. [13] separated natamycin from the filtered fermentation broth by vacuum concentration or extracting the crude antibiotic mixture with butanol. These methods need to remove part of the water before pretreatment, and a large number of organic solvents are used, which increases the extraction cost and environmental pollution. In addition, natamycin is prone to partial acidolysis, which affects the recovery rate

Borden et al. [14] extracted high-purity natamycin from the fermentation broth in two steps: they first adjusted the pH of the fermentation broth to 10~11 with NaOH or KOH, added a certain amount of water-soluble solvent, such as isopropanol, dissolved the natamycin in the fermentation broth, and then used cross flow filtration to remove the insoluble solids in the above fermentation broth. Finally, reduce the pH to 5.5~7.5 to precipitate natamycin. The mass ratio of natamycin obtained from the fermentation broth in the precipitated solid can reach 10% to 50%. In order to improve the stability of natamycin in the extraction process, antioxidants (such as BHA, BHT), ascorbic acid, isoascorbic acid, etc. can be added. Natamycin usually exists in the form of hydrated natamycin, which is more stable than anhydrous natamycin

raghoenath et al. [9] separated natamycin from fermentation broth in two steps: ① decomposed mycelium; ② Natamycin was isolated from the treated fermentation broth. The process of decomposing mycelium includes bacteria lysis, solubilization of cellular substances, and fracture of crystal clusters and fibers. The decomposition degree of mycelium can be detected by microscopic observation or viscosity change. The decomposition methods of mycelium include homogenization, high-speed shear force, ultrasonic technology, heat, pH (acidity), enzymatic hydrolysis, surfactant, etc., which can be used alone or in combination. The basis for choosing these methods is that they will not affect the structure and biological activity of natamycin, nor will they decompose natamycin. Then, according to the different diameters and densities of various substances in the hydrolysate, natamycin and impurities were separated by gradient centrifugation. In this way, more than 90% of impurities can be removed, and the separation effect increases with the addition of water and salt. Finally, the crystals containing three water molecules were obtained by vacuum drying (temperature about 40 ℃)

4 main application of natamycin

4.1 application in food

natamycin is widely used as a food preservative. Bunger et al. [15] treated the antibacterial mixture composed of sorbate preservative, natamycin and dihydroxycarbonate in the manufacturing process of beverages and other foods, especially fruit juice beverages, calcium beverages, tea beverages, beverages containing milk solids and proteins, which can effectively prevent the growth of microorganisms in beverages

adding 15mg/kg natamycin to soy sauce can effectively inhibit the growth and reproduction of yeast and prevent the emergence of white flowers. Moreover, natamycin has low cost and has no impact on the quality and flavor of soy sauce [16]. John et al. [17] studied that the inclusion complex formed by natamycin and cyclodextrin can not only greatly increase the water solubility of natamycin without affecting its original structure and antibacterial activity, but also facilitate the uniform spray of natamycin solution on the surface of cheese

haan Deben Rudolf et al. [18] invented a mixed powder made of natamycin and other antibiotics to treat sausage, cheese and other foods. This method can keep sausage at 12 ℃ for at least 60 days without mildew. Natamycin can also be used in jam, butter, orange juice, raw meat, salad sauce and mold prevention []

4.2 medical application

recently, natamycin has been studied and reported in medicine, especially in corneal fungal infection. Jani et al. [21] reported a case of fungal corneal ulcer treated with natamycin and trichia antibiotic ointment. Dorocka bobkowska [22] found that natamycin has a very obvious therapeutic effect on oral candidiasis. Thomas[23] applied natamycin solution locally to the cornea, and found that natamycin also had a significant therapeutic effect on keratitis caused by limited bacteria in the empty position of the forming corner of the oil inlet and return pipes by the manufacturer of the filamentous real experimental machine, and the best solution concentration was 5%. Monika et al. [24] reported that natamycin can treat keratitis caused by Scopulariopsis brevicaulis. Gagandeep[25] et al. Reported that a 65 year old woman was treated with amphotericin b5 in the vitreous because of endophthalmitis caused by aspergillase after cataract surgery? Zi g, natamycin 5%, while atropine 1% treatment, the effect is obvious. Some people have used natamycin and other drugs to treat scleral abscess caused by cataract extraction, and the effect is obvious [26]

buchta loading speed is too fast or too slow [27] and other reports have reported that amphotericin B and natamycin are combined to treat neonatal skin diseases caused by Fusarium umbellatum. Natamycin can also be used to treat skin and mucous membrane diseases, as well as vaginal and pulmonary aspergillosis

5 development prospect of natamycin

natamycin, as a microbial preservative, has attracted much attention because of its safety, natural and healthy characteristics. Countries have invested human and material resources to study it. Natamycin has many advantages: extending the shelf life of food, preventing spoilage caused by yeast and mold; Reduce food recycling caused by deterioration and reduce production costs; Meet the requirements of consumers for natural food; Do not change the flavor of food; Low dose and high efficiency; Long antibacterial effect, etc. Lytocid is a highly effective inhibitor of mold and yeast produced by Taiwan Litong Co., Ltd. the main ingredient is natamycin, which can be widely used in the preservation of all kinds of food (such as dairy products, meat products, baked goods, etc.). In this way, the domestic Ministry of health has also approved the use, and the content of natamycin in dimycin is ≥ 50%

natamycin is a highly effective antibacterial agent in medicine, and there are many studies at present. A foreign company, intercontinental Medical Book Corp, has produced an ophthalmic drug called natacyn for the treatment of eye diseases caused by fungi

with the deepening understanding of natamycin biosynthesis gene cluster, we will actively promote the use of genetic engineering technology to improve the biosynthesis ability of natamycin or modify its chemical structure, and obtain new natamycin derivatives. The research of natamycin will always be a hot spot

Author: state run Lu

source: Feed Industry