Isolation, Purification Of The Antibiotics From The Fermentation And The Hyphae Of Streptomyces Roseoflavus Strain Men-myco-93-63

Streptomyces roseoflavus strain Men-myco-93-63 was a biological agent isolated from potato scab disease declined soil, which showed sound inhibition on many plant pathogens. The objective of the research is to purify and analyse the main components from the fermentation and the hyphae, and to identify their properties and the structure.At first a primary screening model using Streptomyces scabies strain S87 as a indicator for isolation of the antibiotics from fermentation was established. The fermentation was deposited by chitosan water solution to remove the proteins deposition, and then was separated to two parts by the macropore gel D312: the water-soluble and water-non-soluble. The later part was washed by a gradient of ethanol, and separated into three parts. Their bioassay were all investigated. The active substance were from the 70% part, which was isolated by the retaining screen column Sephadex G-15, analyzed by the reverse-phase high-performance liquid chromatography (HPLC), and detected by the Photodiode Array Detector(PDA).The chromatographic conditions were as follows: the column as Agilent ZORBAX Extend-C18 5um 4.6×250 mm;the flow rate: 1 ml/min;the mobile phase, 30%-80%-100% (acetonitrile: water). The substance was instability and decompounded in the low-temprature conditions. The water-soluble part was separated by the iron exchange gel D81, which was washed by 5% HAc. After making the pH to 7 by using NH₃·H2_O, the substance was separated by the retaining screen column Sephadex G-10. The samples above were under bioassay and the ELSD detector, compared with the two results and then mixed the parts with the same bioassay effect on the pathogens. After concentrated and freezing-desiccation treat, a white powder was obtained. However, the powder could not inhibit the pathogens.A primary screening model using Verticillium dahliae strain V41 as a indicatior for isolation of the antibiotic from the hyphae was used in the process. The hyphae were treated with the acetone and ultrasonic vibration. The treated solution was evapored in decompression and crystalled in the ethyl acetate, from which a yellow powder was obtained. By using the macropore gel XAD-1600 and the ODS C18 column for separation of the solution, a group of analogy substances were obtained. The monomer that was prepared by the HPLC decomposed continually, and turned back to its original condition after 30 min. At last, based on their IR, ESI-MS and H-NMR spectrum data, we suggested that the molecular weight was about 737. Because the monomer could not obtained in the study, the particular structure was notobtained in this research yet.