• Proceedings of the Materials Research Society of Korea Conference
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• 1993.05a
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• pp.32-32
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• 1993

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.139.1-139
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• 2003

Tissues from woody plant contain higher amount of phenolic compounds and polysaccharides, which give inhibitory effects on reverse transcriptase and/or Taq ploymerase. The common multiple-step protocols using several additives to inhibit polyphenoic compounds during nucleic acid extraction are time consuming and laborious. Sodium sulfite (Na$_2$SO$_3$) was used as inhibitor of polyphenolic oxidases in extraction buffer and compare it's effect between commercial RNA extraction kit and small-scale double-stranded RNA (dsRNA) extraction by RT-PCR. During nucleic acid extraction procedure, addition of 0.5％-1.5％ (w/v) sodium sulfite to Iysis buffer or STE buffer resulted in lighter color change than extracts without sodium sulfite and improve the RT-PCR detection. When commercial RNA extraction kit used, optimal concentration of sodium sulfite were variable according to the host plant. However, using dsRNA as RT-PCR template, 1.5％ sodium sulfite in STE buffer improves the detection of both viruses and unspecific amplifications were reduced significantly, Furthermore, when viruses existed at low titers in host plant, small-scale dsRNA extractions were very reliable.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.237-238
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• 1998

The kinetics of sulfite oxidation must be fast and the concentration of sulfite must be low to emulate oxygen uptake by blood. The kinetics were studied yielding a first order rate constant in sulfile, zero order in oxygen. Limitations of the technique were evaluated using the experimental rate constant and an adaptation of Lightfoot's approximation, while the reaction of hemoglobin is reversible and essentially instantaneous, that for sulfite is irreversible and finite. Thus if the approach to saturations not monotonic or if the mass transfer resistance is significantly lowered, e. g. when blood film thicknesses are thinner than a few hundred microns, deviations may occur.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.1
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• pp.11-15
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• 1977

Brownish discoloration develops very rapidly in the storage of dried oyster. This undesirable browning is mainly caused by the series of reactions of sugar-amino condensation, enzymatic oxidation of tyrosine and/or the oxidative rancidity of lipids in the tissue of oyster. Sulfites are commonly used as inhibitors for Maillard type browning reactions in agricultural products. The inhibitory effect of sulfite treatment on canned oysters was also confirmed in some investigations. The results suggested that sulfites not only work on blocking tile amadori rearrangement but also on the reduction of free tyrosine which retards the progress of enzymatic oxidation of tyrosine tyrosinase. In this paper, the effect of sodium sulfite treatment on the reduction of reducing sugar and free tyrosine as a function i)f browning inhibition in oyster was tested and other treatment with glucose-oxidase and yeast were also applied. In preparation of samples, fresh oysters were soaked in sodium sulfite solution by various concentration for different treating times, washed in running water to remove the sulfite residue, and finally dried in the shade. In the result, the treatment of sodium sulfite was certainly effective on the reduction of both free tyrosine and reducing sugars in fresh oyster. The best results were obtained by the treatment of 0.5M sodium sulfite solution for 60 minutes each for soaking and washing. Treatment with, glucose-oxidase and yeast solutions, however, did appear somewhat effective but it required so much time for a certain effect that it seemed not practically applicable.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.940-946
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• 1996

One of the biggest Problems in making jeotkal is the reduction of its shelf-life when lowering the salt content from 20-30% to below 10%. Therefore, in order to extend the shelf-life of the low-salted jeotkal, prior to setting the minimum allowance value of sulfiting agents as food additives for fermented fish products, the preservative effects of sulfite salts on the low-salted myungranjeot (soused roe of Alaska pollack) were studied through various chemical and microbial analyses. The pHs of the low-salted Myungranjeot treated with bisulfite and metasulfite salts rapidly decreased in the biginning of fermentation, while the lactic acid contents increased constantly. Sodium bisulfite and metasulfite enhanced the production of $NH_2-N$ after 10 day-fermentation, whereas they inhibited the production of VBN, TMA and TBA, and the growth of microorganisms including fungi during fermentation. The estimated shelf-lives of low-salted myungranjeot treated with control, sodium sulfate, sodium bisulfite, and sodium metasulfite on the basis of VBN 50 mg% were about 16, 14, 20 and 24 days, respectively.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.29 no.3
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• pp.34-42
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• 1997

This study was carried out to investigate the proper cooking conditions of soda-anthraquinone and alkaline sulfite-anthraquinone pulping of rice-straw, and get basic data f9r the use of rice-straw chemical pulp through the test of characteristics and physical properties of pulps made in the various cooking conditions From the experimental results , we can conclude as follows. In the soda-anthraquinone pulping of rice-straw, the optimum cooking conditions were 60 min. at $150^{\circ}C$ in the amount of caustic soda of 20% with the addition of anthraquinone(0.05%). And total yield, Kappa No. and brightness of pulp made in the condition above mentioned were 41.9%, 7.7 and 51.1 respectively. In the alkaline sulfite-anthraquinone pulping of rice-straw, the proper mixing ratio of cooking chemical(caustic soda : sodium sulfite) was 50:50. And the optimum cooking conditions were 60 min. at $150^{\circ}C$ in the amount of cooking chemical of 20% with the addition of anthraquinone(0.05%). At that time, the total yield, Kappa No, and brightness of pulp were 50.1%, 9.1 and 40.2 respectively. As a result, the alkaline sulfite-anthraquinone pulping was superior to the soda-anthraquinone pulping in the aspect of yield, but inferior in the viewpoints of Kappa No. and brightness. For the comparison of qualities of pulps made in the various cooking methods and conditions, the physical properties of four sorts of pulps were tested. As a result, soda-anthraquinone pulps were superior to alkaline sulfite-anthraquinone pulps in the various strengths excluding tear strength and brightness. On the other hand, pulps made in the condition of addition of cooking chemical of 20% were superior to pulps in the dosage of 15% in the aspects of all the strengths and brightness.

• Korean Journal of Medicinal Crop Science
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• v.6 no.4
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• pp.245-250
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• 1998

This research was carried out to investigate the effective methods of browning inhibition on Paeonia lactiflra Pall during hot air dehydratin. After drying for 36 hrs without pretreatment and with briquet fumigation moisture contents of Paeonia lactiflora Pall. was 16.0% and 16.2%, respectively, while with acidic solution, sulfite salt solution and blanching it was lower of 13.5, 12.9 and 14.8%, respectively. Using freeze drying moisture content was highest of 18.8%. The Hunter values of dried Paeonia lactiflora Pall., L, a, band ${\triangle} E$ showed that non-treatment had the most browning with 61.60, 1.89, 10.20 and 39.78, respectively, while briquet fumigation and sulfite salt solution were excellent in reducing browning. During freeze drying browning didn't occur. Paeoniflorin content was 2.41 and 2.51 %, respectively, in briquet fumigation and sulfite salt solution and was the highest (2.70%) in freeze drying. The content of $SO_2$, was 0.63% both in briquet fumigation and sulfite salts. It was 0.15% and 0.17% higher than nontreatment and freeze drying. The most effective pretreatment to inhibit browning of Paeonia lactiflora Pall. was soaking in sulfite salt solution $(0.5% NaHSO_4-0.5% Na_2S_2O_3)$ considering many things such as manpower, economical efficiency, drying time, commodity, etc. but safety should be evaluated to treat sulfite salts solution on peony roots.

• Bulletin of the Korean Chemical Society
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• v.29 no.7
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• pp.1295-1296
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• 2008

• Journal of the Korean Wood Science and Technology
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• v.22 no.1
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• pp.28-33
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• 1994

The chemical compositions of pine bark from mechanical pulp industry were determined, and effect of Ca base acid sulfite on bark cooking was investigated under various conditions. The pine bark was composed of 39.5 % alkali extractives, 50.3 % lignin, and a small amount of carbohydrate. The contents of alkali extractives and lignin were remarkably higher than those of pine wood. The bark was composed of high content of arabinose and xylose, while the wood was composed of high content of mannose. When pine bark was cooked with 75 % free acid at 145 $^{\circ}C$, the rate of cooking and delignification was improved with the increase of total acid, but it was very difficult to delignify the bark by 50 % and over under these conditions. In the presence of 60~65 % free acid and at 155~165 $^{\circ}C$, initial cooking rate, delignification, and delignification selectivity were considerably increased, but condensation reaction of lignin was considerable at the end of cooking. Therefore, it was shown that pine bark was very difficult to delignify by the Ca-base acid sulfite cooking.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 1993.12a
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• pp.19-20
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• 1993

농산물의 수확 후 취급이나 가공중에 일어나는 효소적갈변 현상은 외관의 변색에 의한 소비자의 기호성을 저하시킬 뿐만 아니라 상품의 가치를 하락시키며, 경제적인 손실을 초래함으로서 현재 식품에 종사하는 기술자나 가공업자에게 가장 관심이 있는 분야이다. 효소적갈변의 주역을 담당하고 있는 polyphenol oxidase(PPO)(EC1.14, 18.1)은 대부분의 식품에 존재하고 있으며 monophenol의 hydroxylation에 의한 o-diphenol화합물의 형성반응(cresolase)과 o-diphenol화합물의 o-quinone으로의 산화반응(catecholase)을 촉배한다. 그리고 여기서 일단 생성된 o-quinone은 다시 다른 o-quinone이나 그밖의 단백질, 아미노산, 환원당 등의 여러 성분들과 상호 반응하여 갈변식품의 특유의 색소인 melanine을 형성한다. 효소적갈변에 의한 품질의 저하는 식품가공산업에서 해결되어야 할 하나의 큰 과제이다. 현재까지 식품산업에서 가장 널리 쓰이고 있는 효소적갈변 저해제는 sylfite류 이다. 그들은 새우의melanosis(blackspot)를 억제하며, 감자, 버섯, 사과와 다른 과채류의 갈변을 방지할 뿐 아니라 쥬우스와 포도주의 off flavors를 일으키는 폴리페놀 플리머의 형성을 감소 시킨다. 그러나 최근 sulfite가 사람의 건강에 좋지않는 부작용을 일으키며, 특히 천식을(asthma)을 지니고 있는 사람이 sulfite가 함유된 식품을 먹었을 경우 사망을 초래할 수 있어 식품첨가물로서 그들의 사용이 미국 FDA에 의해 재평가되고 있다. 최근에 FDA는 셀러드바에서의 sulfite사용을 금지 시켰으며 점차 감자가공품에의 사용을 금지하는 방향으로 나아가고 있다. 따라서 현재 실질적이고 기능적인 sulfite의 대체 화합물의 개발이 절실히 필요한 실정이다. 이러한 배경으로 본 강연에서는 효소적갈변 저해제의 개발과 그들의 식품가공에의 적용 현환 및 화장품, 의약품으로의 응용에 대해 설명하고자 한다.