• International Journal of Industrial Entomology and Biomaterials
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• v.25 no.1
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• pp.133-137
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• 2012

To increase the solubility of lyophilized sericin, we added three types of lyoprotectant: sucrose, trehalose and dextran. The addition of lyoprotectant increased the solubility of lyophilized sericin especially when 1.0% of sucrose, 1.0% and 1.5% trehalose are added. The secondary structure of lyophilized sericin showed that the content of ${\beta}$-sheet or aggregated structure reduced in the presence of lyoprotectant. The morphology of lyophilized was also affected by the addition of lyoprotectant. Whereas flake structure was obtained in the case of pure sericin, a scattered and relatively small flake structure was formed in the presence of lyoprotectant. These finding shows that the presence of lyoprotectant prevents aggregation of sericin molecules and increases the solubility of lyophilized sericin.

• Microbiology and Biotechnology Letters
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• v.43 no.4
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• pp.385-390
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• 2015

In order to develop an eco-friendly biofertilizer, a plant growth promoting rhizobacterium (PGPR), Bacillus sp., SH1RP8 was investigated. SH1RP8 was lyophilized via freeze-drying along with other protective agents that protect cells from lysis. The freezedried powder of Bacillus sp. SH1RP8, containing 5% skim milk (w/v), exhibited the highest survival rate of 30.6% among all the protective agents (skim milk, glucose, and peptone). The lyoprotective effect of the skim milk, mixture including 5% skim milk, and substrates on the survival of the test strain was examined. Control group was added only skim milk and test groups were added skim milk and other substrates. As a result, the group supplemented with both glycerol and 5% skim milk showed the protective effect much higher by 214.29% than the control group. Freeze-dried Bacillus sp. SH1RP8 could be a good candidate as a potential biofertilizer due to its effective PGPR activity.

• KSBB Journal
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• v.9 no.3
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• pp.306-311
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• 1994

Optical resolution of racemic ${\alpha}$-methylbenzylamine was carried out by using Bacillus licheniformis protease in organic media. Enantioselective amidation of racemic amino with an ester as an acyl donor was successfully employed to resolve the racemate. To enhance reaction rate and enantioselectivity, pH-adjustment by lyophilization of enzyme dissolved in buffer, colyophilization with salts or lyoprotectants, selection of solvents and molecular design of esters were investigated. The optimization of the resolution reaction achieved about 30-fold increase in initial reaction rate and about 12-fold increase in enantioselectivity, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.1
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• pp.126-130
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• 2006

The purpose of this research was to study the effect of freeze drying on the microorganisms in kefir. Influences of lyoprotectants and rehydrated media (water at $4^{\circ}C$, $25^{\circ}C$; 10% reconstituted milk at $4^{\circ}C$, $25^{\circ}C$) on the viability of lactic acid bacteria and yeasts in freeze-dried kefir were investigated. Kefir was made from cow milk which was inoculated with 5% kefir grains, and incubated at $20^{\circ}C$ for 20 h. Lyoprotectants (galactose, lactose, maltose, sucrose and trehalose) were added independently before dehydration of kefir by freeze drying. Results indicated significant loss in viability of microorganisms in kefir after freeze-drying. Addition of 10% galactose or 10% sucrose as lyoprotectants significantly increased the survival rates of both lactic acid bacteria and yeasts (p<0.05). The $4^{\circ}C$ rehydration temperature showed the best viabilities for yeasts, however, viability was not significantly affected by rehydration media (p>0.05).

• Applied Chemistry for Engineering
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• v.23 no.6
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• pp.599-603
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• 2012

The enantioselective hydrolysis of racemic styrene oxide in organic solvents was conducted using a recombinant E. coli expressing protein-engineered Mugil cephalus epoxide hydrolase (McEH). The volumetric total activity of the recombinant E. coli was enhanced 2.2-fold by IPTG induction at a mid-exponential growth phase. Among organic solvents with different log P values, isooctane was chosen based on the high activity and the enantioselectivity of McEH. Some lyoprotectants such as skim milk or sucrose enhanced the McEH activity. Enantiopure (S)-Styrene oxide with a 98% ee was obtained from the racemic styrene oxide with a 53.6% yield based on its theoretical yield in isooctane.