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The current study was performed in order to explore the effect of Eurotium cristatum LJSC.2001 on the fermentation quality of raw dark tea. Golden flower loose tea was produced by using E. cristatum LJSC.2001 to ferment raw dark tea from the cultivars Zhuyeqi, Yuntaidaye and Taoyuandaye provided by representative manufacturers (Yuntaishan, Yunshang, Baishaxi and Junhe) in Anhua, Hunan province, and comparative analysis of their taste and aroma quality was carried out by sensory evaluation, basic physicochemical analysis, analysis of catechin components by high performance liquid chromatography (HPLC), and headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). Results showed that after fermentation by E. cristatum LJSC.2001, the dry tea samples were darker in color and fully covered with golden flower; their infusions were darker in color, and had a strong fungal aroma and a mellow and full taste, and the brewed tea was soft. Raw dark tea from Baishaxi had a stronger fungal aroma after fermentation, while retaining a distinct pine smoke-like aroma. The contents of taste compounds including tea polyphenols, free amino acids, soluble carbohydrates, flavonoids, total catechins, myricetin, quercetin, and kaempferol showed an overall decreasing trend. The content of catechins in Yuntaidaye raw dark tea from Yuntaishan and Yunshang declined most. The relative contents of esters and aldehydes increased after fermentation. There were differences in the content of volatile components among the different fermented tea samples, methyl salicylate and (E,E)-2,4-heptadienal being the major ones. Multivariate statistical analysis showed significant differences in volatile composition between golden flower loose tea and raw black tea. There were 19 characteristic volatile components identified including methyl salicylate, (E,E)-2,4-heptadienal, (E)-linalool 3,7-oxide, (E)-furan oxidized linaloa, acetophenone, (E)-2-,(Z)-6-nonadienal, (E)-2-hexenal, (E,E)-3,5-octadien-2-one and n-tridecane. The contents of the nine volatile components increased significantly after fermentation, and they all contributed to the fungal aroma of golden flower loose tea. It can be seen that fermentation by E. cristatum LJSC.2001 can impart a more mellow and fuller taste and a more prominent fungal aroma to raw black tea.

Combined with Thermo-Calc thermodynamic calculation, scanning electron microscopy, X-ray diffraction, EPMA, TEM and EBSD technologies, the effects of Mn content on phase transformation temperature and microstructure of the as-cast Fe-xMn-3.4Al-0.34C(x=4-8) experimental steels were investigated. Results show that with the increment of Mn content, Ae1 continuously decreases from 703.7 ℃ (4Mn) to 501.2 ℃ (8Mn), while final temperature of austenite transition (Ae3) linearly decreases from 1005.6 ℃ (4Mn) to 863.0 ℃ (8Mn). With the increase of Mn content, residual austenite gradually increases from undetectable to 12.6%; the microstructure is gradually transformed from the dual-phase microstructure of cementite (θ)+ the high-temperature ferrite (δ) to the high-temperature ferrite (δ) + martensite (α′) + residual austenite (γ). The residual austenite is distributed in the boundary of δ ferrite and the martensite lath.

Objective: To identify the genotypes of Toxoplasma gondii that infects HIV-positive people in Dali of Yunnan Province through analyzing the genetic loci of the surface antigens SAG1 and SAG3., Methods: A total of 291 blood samples from HIV-positive cases were collected from the HIV/AIDS Prevention and Control Institution in Yunnan. Nested PCR was used to amplify SAGI and SAG3 genes in the blood samples. The products were digested with restriction enzymes Sau96 I, Hae II and Nci I, and sequenced., Results: Of the 291 HIV-positive blood samples, 64 showed successful amplification of SAGI gene, and 42 of SAG3 gene, with product sizes of 390 bp and 225 bp, respectively. Enzymetic digestion of the PCR products resulted in fragments of 350 bp and 50 bp for SAGI, and -200 bp band for SAG3, consistent with RH, a particular type I strain of T. gondii. Sequencing of the SAG1 and SAG3 PCR products showed that their sequence identities with SAGI (Accession No. GQ253073) and SAG3 (Accession No. JX218225.1) of the type I strain of T. gondii were 99.98%-100% and 99.96% -99.98% respectively., Conclusion: The Toxoplasma gondii in HIV-positive cases in Dali of Yunnan Province is the type I strain of T. gondii.

Objective: To preliminarily understand the genotype characteristics of Toxoplasma gondii in blood of HIV-positive persons in Lincang City, Yunnan Province., Method: Two segments of SAG2 gene of T. gondii from blood samples of HIV-positive persons in Lincang City were extracted and amplified by using the nested PCR method and the genotype was identified and compared with the standard strain (Type I) of Toxoplasma gondii., Results: Thirty-five SAG2 genes (241 bp) and 35 SAG2 genes (221 bp) of T. gondii were amplified from 170 blood samples of the HIV-positive people, and 4 of each case were selected and digested with enzyme, then 2 aim gene fragments of each case were chosen and compared with the standard strain (Type I) of T. gondii. The digestion of SAG2 gene (241 bp) showed the genotype of the blood samples was Type I or Type II, and the digestion of SAG2 gene (221 bp) confirmed that the genotype was Type I., Conclusion: It is preliminarily confirmed that the genotype of T. gondii in blood of HIV-positive persons in Lincang City, Yunnan Province is Type I.

Toxoplasma gondii is an intracellular protozoan parasite that infects all warm-blooded animals. The surface antigens of T. gondii with the potential for application as antigens of diagnosis and vaccines have been studied extensively in recent years, especially for P43, P35, P30, P23 and P22. The studies on the surface antigen in tachyzoites of T. gondii are reviewed in this paper.

Objective: To comparatively analyze Toxoplasma gondii separated from HIV-positive people and RH strain GRA6 gene., Methods: By using the nested PCR, the amplification of Dali HIV-positive blood samples and RH strains of Toxoplasma GRA6 genome was performed. The GRA6 gene amplification positive product was selected and the electrophoresis imaging was performed by being digested with the Mse I endonuclease, and the gene sequences were measured and analyzed., Results: The GRA6 gene fragment (800 bp) was successfully amplified, and about 600 bp and 200 bp bands were got by Mse I. The sequencing results showed that T. gondii GRA6 gene positive samples had 2 nucleotide variation compared with T. gondii strain RH, namely 447 base pair at C becoming G, and 623 base pair at G becoming T. At 146 bp and 690 bp, the Mse I restriction sites (TTAA) were found., Conclusion: The preliminary judgment shows that the Dali HIV-positive T. gondii genotype is consistent with RH strain, belonging to genotype I.