ABSTRACT
Coconut oil cake (COC), a byproduct of oil extraction, contains high levels of cellulose. The aim of this study was to isolate a cellulose-degrading yeast from rotten dahlia that can effectively use COC as the only carbon source for cellulase secretion. Based on screening, Meyerozyma guillermondii CBS 2030 (M. guillermondii) was identified as a potential candidate, with the highest cellulolytic activity among the yeast strains isolated, with the carboxymethyl cellulase (CMCase) activity reaching 102.96 U/mL on day 5. The cellulose in COC samples was evaluated before and after degradation by M. guillermondii. Analysis based on field emission scanning electron microscopy (FESEM) revealed that the COC structure was changed significantly during the treatment, indicating effective hydrolysis. Fourier transform infrared spectroscopy (FTIR) of the modified functional groups indicated successful depolymerization of coconut cake. X-ray diffraction (XRD) and analysis of color differences established effective degradation of COC by M. guillermondii. The results demonstrate that M. guillermondii effectively secretes CMCase and degrades cellulose, which has important practical significance in COC degradation.
ABSTRACT
AIM: To study the immune characterization of HBsAg DNA recombinant attenuated salmonella typhimurium vaccine and the expression of enhanced green fluorescence protein gene pEGFPC3 in mice. METHODS: Plasmid pcDNA3s and pEGFPC3 was transformed into attenuated salmonella typhimurium SL8786 by electricity instrument to construct recombinant vaccine SL8786/EGFPC3 and SL8786/pcDNA3s. Mice were immunized with the recombinant vaccine and the quantity of anti-HBs antibody in the sera was measured by time resolved fluorescence immunoassay(TRFIA), While the cytotoxocity of CTL was measured by LDH release assay. RESULTS: It produced strong specificity CTL response after taking SL8786/pcDNA3s orally to mice and anti-HBs was highest in 11 weeks. EGFPC3 expression in two mice spleen cells was detected by flow cytometry(FCM). EGFP masculine ratio is 19.20% and 17.36% respectively. but SL8786/pcDNA3 in two mice spleens cell EGFP masculine ratio only is 1.95% and 1.63%. The mice was taken SL8786/EGFPC3 orally after three weeks, fluorescence expression in its liver, spleen, kidney, chest gland, duodenum, muscle, etc. were observed. CONCLUSION: HBV DNA vaccine can induce specific cellular and humoral immune responses in vivo in mice by oral. Recombinant attenuated salmonella typhimurium SL8786/EGFPC3 we constructed. It has green fluorescence expression in mice's partial organization, and it offers a model for research gene engineering vaccine.
