Isolating and Screening of Effective Decomposing Strain of Silkworm Chrysalis Protein and Study on Parts of Its Enzymatic Properties

[Objective] The research aimed to obtain an effectively-decomposing strain of silkworm chrysalis protein and discuss its enzymatic properties.[Method] The effectively-decomposing bacteria of protein was isolated from the decayed silkworm chrysalis by using dilution plate and its enzymatic properties were tested after primary screening and second screening.The enzyme activity was determined and the intermediate and small molecule protein content in silkworm chrysalis was measured after solid-state fermentati...

Isolation,Screening and Primary Identification of a Keratin-degrading Fungus

[Objective] The paper was to provide new germplasm sources for efficient and economical degradation and utilization of animal keratin.[Method] The keratin-degrading fungus was isolated,screened and primarily identified by using the combination method of traditional isolation and screening,solid culture-medium degradation and animal test.[Result] A strain of non-pathogenic filamentous fungi with high degradation efficiency was obtained,which was preliminarily identified to be a species in Mucoraceae.[Conclusion] The discovery of the strain enriched the family members of keratin-degrading fungus,and provided new germplasm resources for degradation and utilization of animal keratin.

Isolation and Screening of Oenococcus oeni and Its Medium Optimization

[Objectives] This study was conducted to further improve the application of Oenococcus oeni in the wine brewing industry. [Methods] O. oeni was isolated, screened, and identified, and medium optimization was performed to determine the best medium, temperature and oxygen conditions. [Results] O. oeni grew better in mFT80 medium, and the culture conditions were 25 ℃ and an anaerobic condition. [Conclusions] This study provides a reference for the development of China’s wine industry.

Isolation and Screening of Cd-tolerant Bacterial Strains from Paddy Soils around Lead-zinc Tailings

Microorganisms being used in Cd-contaminated soil remediation have broad prospects in application.In order to obtain more Cd-tolerant microbial resources,paddy soils around lead-zinc tailings were collected to extract Cdtolerant bacterial strains by using the methods of enrichment culture,purification and gradient screening.The strains were identified by morphological and biochemical characteristics and 16S rDNA sequence analysis.The Cd-tolerance and Cdadsorption abilities were then analyzed.The results showed that 6 Cd-tolerant bacterial strains were isolated,3 strains could grow in solid medium which had a cadmium concentration of 700 mg/L.These three strains(i.e.KGJ,KDT,and TU)were members of the Pseudomonas genus(Pseudomonas sp.)identified by morphological and biochemical characteristics and 16S rDNA sequence analysis.The growth curve indicated that the growth rates of the strains were obviously inhibited under 250 mg/L cadmium treatment.The three strains were tolerant of cadmium concentrations over 250 mg/L for long periods of time up to the stationary phase,and TU had the strongest Cd-tolerance.The order of metal tolerance of TU to different heavy metals was Cd^2+ >Zn^2+ >Pb^2+respectively.Chemical analysis showed that the adsorption quantity of the 3 bacterial strains of KGJ,KDT,and TU were 7.596 mg/g,12.237 mg/g and 36.926 mg/g respectively by dry-weight,when the concentration of cadmium was 150 mg/L.All 3 strains had good tolerance and ability to adsorb cadmium,and therefore are considered important potential microbial resources for the remediation of Cd pollution in soil.

Study on Isolation and Degradation Characteristics of an Aniline-degrading Strain

[Objective] The research aimed to screen out an efficient aniline-degrading strain and study its degradation characteristics. [Method] By domesticated enrichment culture, an efficient aniline-degrading strain named as DA-K was isolated from activated sludge sample collected from a chemical plant in Henan. DA-K could use aniline as the sole carbon and nitrogen sources. The strain was carried out physiological and biochemi- cal identification, and its biological degradation characteristics were studied. [ Result] DA-K strain was G - and red-shaped, and its colony color was off-white. It was initially determined as Acinetobacter sp. By measuring, the optimum growth temperature and pH for DA-K were respectively 30 ~C and 6.0. DA-K strain could grow well in inorganic salt medium with aniline of 2 500 mg/L. After shaking for 96 h under the conditions of pH 6.0, 30 ℃, 180 r/min and 1 000 mg/L of aniline, the degradation rate of the aniline by DA-K could reach nearly 80%. [ Conclusion] The DA-K strain had a higher aniline degradation efficiency and actual treatment capability of the aniline wastewater, which laid foundation for establishing gene engineerincl strain.