This study was conducted to determine the effects of partial replacement (40.0%) of sodium chloride by potassium chloride, potassium lactate and calcium ascorbate on quality characteristics of cooked pork ham during cold storage. The cooked pork hams with partial replacement of sodium chloride by potassium chloride and potassium lactate had lower lightness (L*) and higher bitterness than others (p <0.05). However, redness (a*), yellowness (b*) and overall acceptability of sensory properties were not different among the treatments (p >0.05). The partial replacement of sodium chloride by all substitutes leads to increase tenderness (p <0.05). There are no problems in microbiological stability and lipid oxidation of cooked pork hams with 40% replacement of sodium chloride by potassium chloride, potassium lactate and calcium ascorbate during cold storage. Therefore, it is possible to use potassium chloride, potassium lactate and calcium ascorbate as partial substitutes of sodium chloride in cooked pork ham.

환경 스트레스에 의해 야기되는 활성 산소종에 의한 피해에 내성을 가지는 식물의 개발을 위하여 딸기 유래의 cytosolic ascorbate peroxidase 유전자(ApxSC7)를 Agrobacterium tume-faciens LBA4404를 매개로 형질전환 시켰다. Hygromycin으로 선발된 캘러스로부터 재분화 된 식물체는 야생형과 비교하여 형태적으로 차이를 나타내지 않았다. PCR 및 Southern blot 분석을 통하여 형질전환 식물체의

감귤류 (자몽, 레몬, 금귤, 밀감 및 오렌지)를 착즙하여 얻은 쥬스를 sep-pak C_18 cartridge를 사용하여 ascorbate 및 phenolic 획분으로 분리한 다음 pH를 달리한 in vitro 반응계에서 아질산염 소거 및 N-nitrosodimenthylamine(NDMA) 생성억제 효과를 분석하였다. 감귤류 쥬스 ascorbate 획분의 아질산염 소거능은 5ml 첨가시 pH 2.5 에서 79.9 ~ 98.6%, pH 4.2에서 48.5 ~ 86.3%였으나, pH6.0에서는 35.2% 이하였다. Phenolic 획분은 ascorbate 획분에 비해 높은 소거능을 보였으며 특히 pH6.0 에서는 ascorbate 획분에 비해 2배 이상의 높은 소거능을 나타내었다. NDMA 생성억제 효과는 phenolic 획분의 첨가시에 월등히 뛰어나 pH 2.5의 반응용액에 금귤, 밀감 및 오렌지쥬스의 phenolic 획분을 첨가했을 때 92.8% 이상이었으나, ascorbate 획분이 첨가된 경우에는 NDMA 생성 억제 효과를 거의 나타내지 못하였다. 따라서 감귤류 쥬스의 NDMA 생성억제와 관련된 주된 인자는 phenol 화합물인 것으로 사료된다.

A study was undertaken to determine the thermal inactivation of Escherzchia coli O157:H7 as influenced by the effects of temperature, time, suspension medium and ascorbate. Tryptic soy broth was more heat resistant than phosphate buffer (pH 7.1), with D values of 1.52-1.68 min at 60℃ and 1.51-1.63 min at 70℃ compared with 1.52-1.65 min at 60℃ and 1.26-1.61 min at 70℃ for phosphate buffer as suspension medium. E. coli O157:H7 was completely inhibited within 30 min when small inoculum (10^6 CFU/ml) was heated at 70. When E. coli O157:H7 was preheated at 48℃ for 60 min in phosphate buffer before heating, D values were 1.28-1.60 min at 60℃, and 1.13-1.56 min at 70℃, showing that preheating increases the heat resistance of the strain. Phosphate buffer containing ascorbate (0.001 M) was enhanced the thermal inactivation of the strain when inoculated as large inoculum (10^9 CFU/ml), while ascorbic acid was no effect at low cell concentrations (10^6 CFU/ml).

돔배기 육, 연골 및 껍질의 저장 중 총균, 대장균 및 병원성미생물의 생육에 미치는 chitosan-ascorbate(CA)(0.01%) 및 모려(10 ppm)의 처리효과를 조사하였다. 에서 6일간 저장한 결과 대조구의 경우 총균수는 육, 연골 및 껍질에서는 각각 4.24, 3.81, 2.20 log cycle이 증가하였으나 CA처리구는 육에서는 2.66 log cycle이, 연골에서는 2.37 log cycle이, 껍질에서는 1.24 log c

Chitosan-ascorbate (CA)를 표면처리한 후 에서 감압건조한 과메기(VD-과메기)의 품질특성과 고지방식이 흰쥐의 혈청지질과 항산화계 효소활성에 미치는 영향을 조사하였다. VD-과메기의 제조기간은 360~4800.2~0.5128.3~135.040℃40℃서 감압건조하는 방법은 제조기간을 크게 단축시킬 뿐만 아니라 과메기의 위생성과 영양성을 높일 수 있는 방법으로 산업적 활용이 기대

본 연구는 chitosan-ascorbate (CA) 첨가(0.1%)가 물김치의 숙성에 미치는 영향과 고콜레스테롤식이 흰쥐의 혈청지질에 미치는 효과를 조사하였다. CA첨가 물김치는 무첨가에 비하여 탁도가 낮고, 보존성이 높으며, glucosamine함량이 무첨가에 비하여 배, SOD활성이 로 높았으며 2025 kDa의 chitosan으로 제조한 CA2025가 가장 양호하였다. 동물실험은 SD계 흰쥐로 정상식 이군(NC), 고콜레스테롤 식이군(HC

A cytosolic ascorbate peroxidase, hydrogen peroxide-scavenging enzyme, was characterized from Codonopsis lanceolata. The cytosolic ascorbate peroxidase cDNA (CAPX) was 983 nucleotides long and possess an open reading frame of 753 bp with 251 amino acids (MW 27.9 kDa) with pI 5.61. The deduced amino acid sequence of CAPX shows high homology to other known cytosolic APXs (78~83%), but the CAPX was clustered independently from compared ten plant APXs. The CAPX gene was highly expressed in leaf and stem tissues, but not in root. When Codonopsis leaves cut using scalpel were soaked in 1 mM hydorgen peroxide, the expression of CAPX gene was suppressed.

Ascorbate peroxidase (APX) plays a crucial role in the detoxification of hydrogen peroxide. APX activity is maintained significantly higher in the paraquat­treated leaves of the paraquat-tolerant Rehmannia glutinos. This study was conducted to understand structural and regulatory characteristics of APX gene in R. glutinosa. A putative APX cDNA clone (RgAPX1) was isolated from a leaf cDNA library using a partially sequenced expressed sequence tag clone. RgAPX1 is consisted of 1148 bp nucleotides and contains an open reading frame encoding a 250 amino acid-long polypeptide. Deduced RgAPX1 amino acid sequence shares higher sequence similarity to cytosolic APXs. RgAPX1. expression was higher in the leaf than in the flower and root. Southern blot result indicates the presence of one or two RgAPX1-related genes in R. glutinosa genome. RgAPX1 transcription was affected differentially by various stresses and phytohormone. The results indicate that RgAPXl is constitutively expressed in most tissues and its expression is modulated for the immediate and efficient detoxification of H2O2 under normal and stress conditions.

In order to investigate low molecular antioxidants synthesized by enhanced UV-B radiation, we used the seedlings of two rice varieties. Woonjangbyeo, UV-tolerant, and Hwajoongbyeo, UV-susceptible, were subjected under supplemental UV-B irradiation. When rice seedlings were irradiated with UV light for short period, biosynthesis of total phenolic compound, ascorbate and glutathione were momently reduced. With an increase of UV-B radiation, however, those were slightly synthesized. The content of lipid peroxides in UV-challenged rice leaves was considerably increased after 12 hrs of UV-B treatment. Lipoxygenase activity under supplemental UV-B radiation was differently responded on rice varieties.

To assess resistance of transgenic tobacco plants which overexpress superoxide dismutase (SOD) and ascorbate peroxidase (APX) in chloroplasts to water stress, changes in leaf water potential, turgor potential, stomatal conductance and transpiration rate were measured. Leaf water potential in all plants remained high up to day 4 after withholding water but thereafter decreased markedly. In spite of a remarkable decrease in leaf water potential, some of transgenic plants maintained higher turgor potential compared with control plant on day 12. In particular, the transgenic plant expressing MnSOD showed an outstanding maintenance in turgor pressure by osmotic adjustment throughout the experiment, resulting in high stomatal conductance and transpiration rate. However, among transgenic plants, osmotic potential was reduced more effectively in multiple transformants such as the double transformant expressing both MnSOD and APX, and the triple transformant expressing CuznSOD, MnSOD and APX than single transformants. Consequently, further research is needed to get general agreement on the tolerance of transgenic plants to water stress at different growth stages for each transgenic plant.