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This thesis aims at natural enzyme inhibitor and describes the
screening and identification of strains which could produce
hen egg white lysozyme inhibitor isolating from the soil. After
screening, we isolate four strains. They are Erwinia
rhapontici H-55, Pseudomonas aeruginosa M-1001,
Enterobacter sakazakii M-1002 and Enterobacter cloacae M-1204
after identi- fication and characterization respectively.
Strain M-1001 has the best inhibitory activity. Studying on
optimum cultural condition of strain M-1001, maximum
inhibitory activity was obtained when the strain was grown
aerobically in a medium consisting of 0.25% glucose, 0.25% beef
extract, 0.25% polypeptone, 1.0% sodium glutamate and 1.0%
soluble starch ( pH 7, 37℃, 180rpm, 48 hours ). The
inhibitors were purified from the culture supernatant of
P. aeruginosa M-1001 by ammonium sulfate fractionation, DEAE
Sepharose CL-6B chromatography and Sephacryl S-200 gel
filtration. We purify two inhibitory active fraction named F-Ⅰ
and F-Ⅱ. Their molecular weights are 57000 and 33000
daltons. The pH stability are 6~10 and 6~11. Thermal
stability are 50℃ and 40℃. Respectively, their specific
activities could increase about 20 and 7.5 times. On the test
for biological activity of inhibitor produced by strain
M-1001. The growth of Gram positive bacteria could be
inhibited. The result is good for development of new antibiotic.
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