• 한국식품과학회지
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• 제26권3호
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• pp.204-212
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• 1994

곶감중 당은 주로 glucose, fructose, mannose였다. 당도 조절을 위하여 가한 sucrose는 즉시 단당류로 분해되었다. Glucose는 $25^{\circ}C$ 발효의 경우 발효 8일째 거의 발효가 완료되었으나 $15^{\circ}C$ 경우 75% 정도 발효되었다. 발효속도는 발효온도에 관계없이 glucose>fructose>mannose 순이었다. 곶감에서 검출된 유기산은 acetic acid, levulinic acid, 4-methylvaleric acid, oxalic acid, N-butyric acid, succinic acid 등이었고 발효온도에 관계없이 발효초기에 감소하다 4일, 6일째 증가후 다시 감소하는 경향이었다. Levulinic acid는 발효가 진행됨에 따라 가장 급격히 감소하였다. Acetic acid와 4-methylvaleric acid는 발효가 진행됨에 따라 증가하였다. 유리 아미노산은 Ala, Gly, Val, Leu, Ile, Met, Ser, Pro, Phe, Asp, Hyp, Glu, Asn, Lys, Gln, Arg, His, Trp, Tyr 등 19가지가 검출되었다. 총 유리아미노산의 함량은 발효온도에 관계없이 발효 2일까지는 감소하다가 다시 증가하여 2주에서 원료용액과 같은 수준이었다. Ethanol함량은 발효 8일째까지는 $25^{\circ}C$우 9.4%(v/v), $15^{\circ}C$ 발효의 경우는 5.3%(v/v)였으나 12주째에는 $25^{\circ}C$ 경우 9.4%(v/v), $15^{\circ}C$ 경우 14.5%(v/v)로 $15^{\circ}C$ 경우가 알코올함량이 높았다. 고급 알코올은 2-methyl-1-propanol, 3-methyl-1-butanol, 2-methyl-1-butanol, 2-methyl-2-propanol 등이 0.001%(v/v)에서 0.06%(v/v) 범위에서 검출되었고 발효기간의 경과에 따라 증가하는 경향이었다.

• 대한수의학회지
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• 제25권1호
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• pp.7-17
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• 1985

Many investigators have been pursuing various attempts so far to produce hepatitis B surface antigen(HBsAg) vaccines using the techniques such as isolation from plasma of chronic HBsAg carrier, recombinant DNA technique or preparation of synthetic peptides specific for immunogenic determinants. Hepatitis B virus can not grow on any cell lines by the tissue culture technique at the present time. The plasma of chronic HBsAg carrier is expensive and its source is limited. The HBsAg from the recombinant DNA technique gave still very low yield. Another approach, therefore, has been initiated to develop a synthetic hepatitis B virus vaccine. The possible use of several distinct synthetic vaccines in prophylaxis can be facilitated by availability of full synthetic immunogens. Peptides synthesized for potential application as antiviral vaccines have been mostly tested in the form of conjugates with carrier proteins, although the free synthetic peptide can be immunogenic. To understand basic knowledges on the antigenicity and immunogenicity of a synthetic peptide specific for major immunogenic determinant of HBsAg, a nonapeptide, $H_2N^{139}Cys-Thr-Lys-Pro-Thr-Asp-Gly-^{146}Asn-Aba$ COOH, which corresponds to HBsAg amino acid residues 139 to 147, was synthesized by the Merrifield's solid-phase method with a slight modification. The antigenicity and immunogenicity of this specific synthetic peptide were examined comparing with purified plasma-derived natural HBsAg. The results obtained are as follows; 1. The peptide synthesized showed the identical amino acid composition to the theoretical value. The degree of purification and molecular weight were acertained by methods of high performance liquid chromatography and mass spectrometry. 2. Using m-maleimidobenzoyl-N-hydroxysuccinimide ester as a conjugating agent, the synthetic peptide was conjugated to rabbit albumin and ${\gamma}$-globulin, tetanus and diphtheria toxoids, and keyhole limpet hemocyanin. Their conjugation yields were 8.3, 9.5, 15.8, 13.5, and 11.2%, respectively. 3. The natural HBsAg was purified from plasma of chronic HBsAg carrier. By the electron microscopic observation of the purified natural HBsAg preparation, no Dane particles were observed and the preparation showed negative DNA polymerase activity. 4. Antigenicity of the synthetic peptide and the plasma-derived natural HBsAg was determined by competition radioimmunoassay using $^{125}I$-natural HBsAg. Their 50% inhibitions appeared as $90{\mu}g/ml$ and $0.12{\mu}g/ml$ for the synthetic peptide and the natural HBsAg, respectively. This indicates that the former was about 750-fold less antigenic than the latter. 5. Immunogenicity of the synthetic peptide was determined by administering the peptide-carrier conjugates into rabbits with and without Freund's complete adjuvant. Regardless the carrier proteins and adjuvant, positive immune responses to the synthetic peptide were observed. The higher antibody titers, however, were shown in the groups administered with Freund's complete adjuvant. 6. Immunizing dose 50% in mice of the various peptide-carrier conjugates was 5.47, 6.00, 65.16, 31.25 and $13.03{\mu}g/dose$ for rabbit albumin and ${\gamma}$-globulin, tetanus and diphtheria toxoids, and keyhole limpet hemocyanin, respectively, while the natural HBsAg showed $0.65{\mu}g/dose$. 7. It was postulated that homologous proteins prefer to heterologous ones as the carriers.