Kyung-Hoan Im

Studies on Immuno-Modulatory and Antitumor Effects of Crude Polysaccharides Extracted from Paecilomyces sinclairii

Neutral salt soluble [0.9% NaCl (Fr. NaCl)], hot water soluble (Fr. HW) and methanol soluble (Fr. MeOH) materials were extracted from Paecilomyces sinclairii. In vitro cytotoxicity tests. Fr. HW was not cytotoxic against MH3T3, Sarcoma 180 and HepG2 cancer cell lines at the concentration of , while HT-29 cell line was cytotoxic at the concentration of . Fr. NaCl and Fr. MeOH were slightly cytotoxic to the cell lines. Intraperitoneal injection with Fr. NaCl and Fr. MeOH exhibited antitumor activity with life prolongation effect of 32.3% in mice inoculated with Sarcoma 180. Fr. NaCl improved proliferation of spleen cells and the immunopotentiation activity of B lymphocyte by increasing spleen cell numbers and the alkaline phosphatase activity by folds, respectively. Fr. NaCl generated of nitric oxide (NO) when cultured with RAW 264.7, a mouse macrophage cell line, at the concentration of , while iipopolysaccharide, a positive control, produced . The Fr. NaCl showed the hightest antitumor effect and activation of B lymphocytes and macrophage. From these results, antitumor effect of P. sinclaitii was likely due to immunopotentiation activity.

Identification and quantification of carotenoids in paprika fruits and cabbage, kale, and lettuce leaves

Twelve carotenoids were identified in Korean leafy vegetables and paprikas. by high-performance liquid chromatography, Carotenoid contents varied greatly, with red paprika having a higher antheraxanthin and capsanthin contents than other paprikas. Orange paprika had higher levels of zeaxanthin, β-cryptoxanthin, lutein, and α-carotene compared to those of other paprikas. The results of Pearson’s correlation analysis using quantitative data of carotenoids revealed that significant positive relationships were apparent between capsanthin and antheraxanthin (r=0.9870, p <0.0001), zeaxanthin and α-cryptoxanthin (r=0.9951, p <0.0001), as well as lutein and α-carotene (r=0.9612, p <0.0001). Because the correlations between carotenoids levels have provided valuable information regarding metabolic associations, this technique will contribute to identifying metabolic links for carotenoid biosynthesis.

Effects of Heavy Metals on Plant Growths and Pigment Contents in Arabidopsis thaliana

The effect of heavy metals on seedling growth and pigment levels was studied in Arabidopsis using essential (Cu, Mn, and Zn) and non-essential metals (Pb and Hg). Generally increasing the concentrations of the metals resulted in a gradual decrease in root and shoot lengths, a decrease in chlorophylls, an increase in anthocyanins and a fluctuation in carotenoid content depending on the metal types. The toxicity of the metals decreased in the following order: Cu > Hg > Pb > Zn > Mn. Among the five metals, Cu was exceptionally toxic and the most potent inducer of anthocyanins. Pb induced the smallest quantity of anthocyanins but it was the strongest inducer of carotenoids. It suggests that the Cu-stressed Arabidopsis may use anthocyanins as its main antioxidants while the Pb-stressed Arabidopsis use carotenoids as its main protectants. All of the five metals induced an accumulation of anthocyanins. The consistent increase in anthocyanin content in the metal-stressed Arabidpsis indicates that anthocyanins play a major role in the protection against metal stresses.

Targeted metabolite profiling to evaluate unintended metabolic changes of genetic modification in resveratrol-enriched rice (Oryza sativa L.)

Resveratrol-enriched rice (RR) includes the stilbene synthase gene for resveratrol synthesis and the phosphinothricin-N-acetyltransferase gene for glufosinate tolerance. To investigate unintended effects resulting from RR’s genetically modified chemical composition, 56 polar and nonpolar secondary metabolites were analyzed with gas chromatography–mass spectrometry in RR and conventional non-transgenic rice. Rice was cultivated during two seasons along three representative climatic regions in the Republic of Korea. Principal components analysis was used to visualize chemical composition differences among rice samples. The results showed that chemical composition was more influenced by growing year and location than by whether or not the rice was transgenic. Pearson’s correlations and hierarchical clustering analysis also indicated no difference in the biochemical structures of RR versus non-transgenic rice. In addition, the glufosinate-ammonium treatment did not significantly change RR chemical composition.

The Characteristics of Cultural Conditions for the Mycelial Growth and Fruiting Body Formation of Paecilomyces sinclairii

매미누꽃동충하초(Paecilomyces sinclairii)를 전라남도 백양사의 인근 숲에서 채집하여 균주를 순수 분리하고 균사의 최적 배양조건과 특성을 조사하였다. 균사생장에 적합한 pH는

Global Analysis of Gene Expression upon Acid Treatment in Arabidopsis thaliana

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Overexpression of a Kunitz-type trypsin inhibitor (AtKTI1) causes early flowering in Arabidopsis

의 범위였으며 pH 8에서 가장 왕성한 균사생장을 보였고, 온도는

Overexpression of the downward leaf curling (DLC) gene from melon changes leaf morphology by controlling cell size and shape in Arabidopsis leaves

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Arabidopsis leaf necrosis caused by simulated acid rain is related to the salicylic acid signaling pathway

가 적합하였다. 균사생장에 가장 적합한 배지는 Hamada 배지였으며 탄소 영양원은 dextrin, 질소 영양원은 glutamine인 것으로 조사되었다. 균사의 생장은 C/N비가 20:1일 때, 옥수수추출물과 우유가 혼합한 배지에서 가장 양호하였다. 자실체는 20%의 누에번데기가 첨가된 현미배지에서 500lux,

Altered cell shapes, hyperplasia, and secondary growth in Arabidopsis caused by beet curly top geminivirus infection.

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