Research On The Separation And Identification Of Solid-state Fermentation Kudzu Root "Jinhua" Fungus And The Activity Of Fermentation Products

Isoflavone compounds is the most important bioactive components of pueraria.It has antioxidant, protecting cardiovascular, inhibiting tumor cell growth and other physiological and pharmacological activity. At present, the use of pueraria resources have focused on the application of kudzu root starch, ignoring the extraction of isoflavone compounds, pharmaceutical and process disjointed phenomenon is serious, leading to a large amount of waste of resources. Eurotium Cristatum,as known as ’Jinhua’ bacteria, is the dominant fungi in the process of brick tea fermentation,has a variety of medical health function,Such as antioxidant, bacteriostat,anticancer,etc.It can use substances such as tannin and starch as carbon source, secrete a variety of extracellular enzymes,for example polyphenol oxidase, pectinase, cellulase, protease and so on.In order to research whether the ’Jinhua’ fungus grow on and biotransformate the kudzu root, get higher active fermentation products. One of advantages of strain was isolated form Fuzhuan Tea.Pueraria lobata, its in the wild as the substrates in solid-state fermentation.Using the DPPH-radical scavenging capacities of fermentation products were investigated, making a determination of the contents of fermentation Products of puerarin were detected by high performance liquid chromatography,to lay the ground for a comprehensive understanding of the biological activity of puerarin derivatives or analogues and research and development of new drug. Study the antibacterial activity of fermented products, to provide theoretical basis for its research utilization. Study the Cherry tomato postharvest storage test use fermented products,, with the selected fruit is Cherry tomato, and discuss the effect and mechanism of fresh-keeping, to provides the new direction of fresh-keeping agent for Cherry tomatoes preservation.At the same time,For improving the antioxidant activity of fermented product optimization puerarin-"golden flower" solid-state fermentation conditions, eventually lay the ground for industrialized production.The test results are as follows:1. One of advantages of strain was isolated form Fuzhuan Tea, named it as LS1,puerarin can provide all the nutrients of the growth of it.LS1 was identified preliminarily as Eurotium cristatum with Genbank accession number of KR812327 by morphological characteristics and the analysis of ITS-5.8S rDNA region.2. Using vitamin C (Vc), BHT, and puerarin as the reference substances,the DPPH-radical scavenging capacities of transformed derivatives were investigated. The results show that the transformed products shows DPPH-radicals scavenging capabilities in vitro.After fermentation, Antioxidant activity of the kudzu in the wild product is obviously better than before at various concentrations.with Significant difference (P<0.05)3. Making a determination of the contents of fermentation Products of puerarin were detected by high performance liquid chromatography.The results show that the puerarin pueraria lobata, its in the wild as the substrates in solid-state fermentation content increased 20.48%、7.00% and 20.29% respectively.4. Detect the inhibition activities of four kinds of pathogenic fungi of three kinds of substrates and fermented product by Plate confrontation method. The results show that all the substrates have broad-spectrum antibacterial activity, but the inhibition activities were worser than the positive control group Evil mildew.After the byconversion of LS1,the inhibition activities of all the transformed products were better than Evil mildew in Alternaria sonali.5. Detection the inhibition activities to five kinds of spoilage bacteria of three kinds of substrates and fermented product by round filter paper method.The results show that that strongest inhibition of Y-2 to Escherichea coli (Inhibitory rate was 12.67±0.09),belongs to moderate sensitivity, as well as only the moderate sensitive inhibition of Y-2 is to Stahylococlus aureus, Bacillus cereus, Bacillus subtilis (Inhibitory rate were 11.40±0.09,10.43±0.05 and 10.93±0.09,respectively).6. At temperature(20℃), humidity(75%),Y-1 and Y-2 were used to cherry tomatoes preservation test (16 days storage). By recording cherry tomatoes decay rate, weightlessness rate,vitamin C (Vc),titratable acid,reducing sugar during storage.Results show that at the end of the storage, compared with the blank control group.Y-1 and Y-2 group significantly reduce the rot rate(53.33% and 45.00%,respectively)and weightlessness rate(4.86% and 4.31%,respectively) of cherry tomatoes, and maintaining high Vc(Descent rate are 11.95% and 14.71%,respectively),titratable acid(Descent rate are 0.26% and 0.30%,respectively), reducing sugar(Descent rate are 1.12% and 1.32%,respectively).7. The DPPH·radical scavenging capacities used for indication,Using single factor and response surface method to optimize the fermentation conditions of kudzu in the wild as the substrates in solid-state fermentation, was as follows:inoculating amount of LS1 6 X 1010 a/mL,the thickness of materials layer 0.6cm,the initial moisture content 100%,fermentation time 5 d,fermentation temperature 30 ℃, the antioxidant activity of fermentation products was the highest,the scavenging DPPH rate was 59.63%.