Screening The Strain With Metabolising Lactic Acid And Investigation Of New Compound Synthesised In Cell

The special fungus was screened, which could metabolize lactic acid to produce a new compound, named LAMOPD (Lactic acid Metabolite of Penicillium decumbens K₁). The strain was identified by the morphological observation and gene homology analysis. Then, the culture character of strain Penicillium decumbens K₁ was studied, and the compound of LAMOPD was separated and purified for analyzing of the structure with the four type of spectrums. The results showed as follow:First, with the lactic acid as the sole carbon source, screening microbes which could metabolizing lactic acid, from different environmental conditions acquisition of the soil samples. As a result, a total of 172 strains had been screened. Then, the strains was cultivated with the lacitic acid as the main carbon source, LC-MS was used to detected the metabolites from the strains. The result showed that a strain named K₁ could synthesize a new substance LAMOPD.Second, the strain K₁ was identified as Penicillium decumbens K₁ by morphological observation and gene homology analysis. The results of Penicillium decumbens K₁ cultivation under different carbon sources showed that it could produce the compound of LAMOPD through metabolizing sucrose, glucose, citric acid, starch, glycerin, corn powder, cotton powder and lactic acid. The concentration of LAMOPD in mediumâ… reached 3.51g/L after 84h of culture.Third, the compound of LAMOPD was obtained after organic solvent extraction and purification by column chromatography. The purity of the compound of LAMOPD could reach 59.34% after eluting from D101 by 10% alcohol-water with the velocity of flowing 2BV/h . After PHPLC separation for two times, the purity of LAMOPD was 90.02%. It could satisfy the need of spectrums analysis. The essence characteristic of LAMOPD were researched by character reactions, such as AlCl3, dragendorff, biuret reaction, gydration engrave trione reaction, HCl-Mg and tris-phenol/chlorofomn, the results showed that LAMOPD might not belong to the protein, amino acid, flavones, polypeptide and alkaloids.Fourth, the structure of new compound LAMOPD was elucidated by UV, LC-MS, IR and NMR spectrum techniques, the results as follow : 1. The material characteristics of the UV absorption wavelength of 222nm, 243nm and 324nm showed that the structure of LAMOPD might contain the conjugate Benzene ring; 2. In the IR spectra, there were absorption peaks by hydroxyl and carbonyl, nitryl, and benzene; 3. LC-TOF-MS showed the weight of the LAMOPD was 281.1097, the ion fragment showed that the structure might contain benzene ring, hydroxy and carbonyl groups; 4. The result of Energy spectrum showed that the element ratio of N : O was 1 : 2 in the structure of LAMOPD; 5. NMR spectra showed that there were hydroxyl, carbonyl, methyl and benzene in the the substance, the molecular formular was C11H11O6N3. Searching for the"SciFinder Scholar database", 161 kinds of compound was found with weight 281, but none of them was completely related with the new compound of LAMOPD, so it came to the conclusion that the LAMOPD was an unknown new compound, and the structure was speculated, but the precision structure of LAMOPD needed further research.