| Fresh feces of Nipponia Nippon, collected without contamination, was inoculated into the common broths and the anaerobic meat liver soups respectively and then cultured for 24~48 h in 37 ℃. Things of the above cultured, after diluted to the same gradient and inoculated on solid culture mediums quantitatively, were cultured for 24~48 h under the condition with oxygen and without oxygen. According to the different colonies from the solid culture mediums, they were isolated and purified. G~+ spore bacilli,G~+ having no spore bacilli,G~+ coccobacteria and G~-bacilli were firstly confirmed through microscopic observation and then the identified tests were carried out, including oxygen needing,amylam,M. R and V. P,O/F,catclase,gelatin liquefaction,KNO3 reduction,indole,ferment of saccharide and mellow,sodium malonate and sodium citrate,phenglalanine,movation,Nacl-phily,acid resistance test and so on. Finally, 22 strains of bacteria were identified. they were B. bifidum,B. mininmum,L. oris,L. brevis,L. panis,L. mali,L. helvericus,L. acidophicus,P. acidpropionici,B. circulans,B. coagulans,B. pantothenticus,E. faecalis,L. paramesenteroides,S. acidominimus,S. intestinalis,lactococcus,klebsiella,citrobater,proteus and B. caccae. Then the experiment inhibiting E.Coli was conducted to 9 strains of lactobacilluse, and the results suggested that B. bifidum,B. mininmum,L. mali,L. helvericus and lactococcus inhibited the growing of E.Coli obviously, especially B. mininmum the best suppressing result so that it was suitable for making microbrobials. In determining the nature, the phenomenon of B.mininmum repressing E.Coli appeared strongly after 48 h. In quantitative test, the metabolic substance of B. mininmum had an increasingly inhibitive effect on E.coli. The concentration of E.Coli, originally 2.25×10~8 cfu/ml, was less than 5×10~5 cfu/ml after being cultured for 36 h. The results of challenged experiment to all isolated strains showed that B. circulans,B. pantothenticus and an unidentified coccobateria were pathogenic to animals apparently, and other isolated germs had no evident pathogenic effect on animals. B. bifidum and B. mininmum were cultured in proliferous culture mediums, and the result showed that improved broth was the best. The result of drug sensitivity test indicated B. bifidum and B. mininmum were high sensitive to Streptomycinum, Kanamycin, Amikacin, Decycline, Erythromycinum and Cefazolin, while resistant to Penicillinum and Ampicillinum. Both of them were tamed in controlled temperature. And the result showed that both of them multiplied quickly in milk medium. Time of solidifying milk was apparently dropped with temperature going up. When 42 ℃, time of solidifying milk was between 3 ~ 5 h. While microbrobials made,B. mininmum was chosed as strain, improved broth as culture medium, alginate sodium as capsule bodies, corn starch as protestants. B.mininmum had been cultured, and then liquid cultivation was centrifuged and measured the concentration. After that microencapsulations were made in the clean bench. The microencapsulations were brown and grainy. Its diameter was between 0.5~1.0 mm. By checking its qualities, the result showed that the efficiency of pack was 64.05%, and that the yield rate of pack was 50.6%, and that its living B. mininmum number was up to 8.6×1011 cfu/ g;and that it could resist the acid of stomach;and almost dissolved in 45 minute in the artificial intestine fluid, the probability of it releasing germs was 94.5%;and after stored 90 d under 4 ℃in freezer, the number of living B. mininmum was 8.0×107 cfu/g. Moreover, the animal protective experiment showed that the microencapsulation had a certain sanitarian function.
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