Min-Su Kim;Yun-Jeong Han;Sharanya Tripathi;Jinwoo Kwak;Jin-Kyung Kwon;Byoung-Cheorl Kang;Jeong-Il Kim
Korean Journal of Plant Resources
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v.36
no.5
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pp.527-539
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2023
Pepper (Capsicum annuum L.) is an important vegetable and spice crop that has been cultivated worldwide. Pepper fruits have unique taste and aroma, providing a variety of antioxidants and compounds important for human health, which makes a high economic value. In addition, there is a high demand for new pepper varieties, according to consumer's preference. However, pepper is a recalcitrant plant for in vitro tissue and organ differentiation and plant regeneration, which makes it difficult to develop demanded varieties using newly developed technologies such as genetic engineering and gene editing. In this study, tissue culture and regeneration conditions were investigated using seven pepper varieties that were obtained from the core-collection of Seoul National University. We observed callus and bud induction and shoot formation using several media composition composed of different cytokinins and auxin concentrations. As a result, it was found that there were differences in callus induction and shoot formation of each variety depending on the hormone composition, and the highest regeneration was shown when the medium containing Zeatin Riboside and the petioles of seedlings were used. In particular, out of seven pepper varieties, CMV980 exhibited a higher regeneration efficiency (approximately 48%) than other varieties, followed by Yuwolcho. Therefore, this study provides CMV980 and Yuwolcho as good candidates that can be used for pepper transformation, which might contribute to the development of various varieties through gene editing technology in the future.
Isolation and identification of Mycoplasma were performed to clarify Mycoplasma infection of mice fed by conventional feeding at two ($K_1$, $K_2$) institutes in Korea. The twenty mice to be tested were randomly sampled from each of 10 breeding colonies in respective institute. Identification of the Mycoplasma strains isolated from the nasal cavity, lung and synovia of mice was made according to the morphology of colonies, biological and biochemical properties with special reference to M. pulmonis, M. arthrotodis and M. neurolyticum. In addition, growth inhibition test was performed using hyperimmune rabbit antisera to the strain PG-22 of M. pulmonis, the strain PG-6 of M, arthritidis and the strain PG-28 of M. neurolyticum and also differentiation of isolates from L-form bacteria was dont by Dieses staining and culture method with passage of the isolates on liquid media eliminated antibacterial drug. On the other hand, a total of 13 strains out of the 44 isolated M. pulmonis from mice was investigated for their susceptibility against 16 antibiotics in vitro. The antibiotic sensitivity test was made using $3{\times}10^4$ organisms/0.3ml on each plate(90mm diameter) with antibiotic mono-or tri-disk. The results obtained are summarized as follows: 1. Out of 20 mice from 10 breeding colonies in Kl institute, mycoplasma-like strains from the nasal cavity of 16 mice(80%) and from the lung of 8 mice(40%) were isolated, while out of 20 mice in K2 institute, M-like strains were isolated from the nasal cavity of 14 mice(70%) and from the lung of 6 mice(30%). However, no mycoplasma-like organisms were isolated from the synovia of the 40 mice examined. All the 44 strains isolated were identified as the organisms of M. pulmonis. 2. Out of the 16 antibiotics tested, penicillin, oleandomycin and bacitracin showed no activity against all the 13 M. pulmonis strains. On the contrary, lincomycin, clindamycin, chloramphenicol, tetracycline, minocycline, kanamycin, gentamycin and tobramycin showed high activity with three different antibiotic concentration of tridisk, but amikasin and spiramycin showed intermediate activity. Other antibiotics such as polymyxin B and colistin showed low activity, while erythromycin showed lower activity than others.
We have conducted in vitro experiments with nano-silver liquid for their effect against various plant pathogenic bacteria. Different types of nano-silver liquid WA-CV-WA13B, WA-AT-WB13R and WA-PR-WB13R were used. These are classified based on different manufacturing processes. The tested bacteria were provided by KACC. We experimented ten bacterial isolates in Clavibacter, Erwinia, Pseudomonas, Ralstonia, and Xanthomonas genera. In order to determine the level of concentrations of control effects, different concentrations (10, 25, 50, and 100 ppm) of each different nano-silver liquid were added in the culture media. As a result, WA-CV-WA13B showed high inhibition effect against C-1 at 10 ppm, and showed minor inhibition effects against P-6, X-1, and X-2. WA-AT-WB13R showed bactericidal effect against P-6 at 10 ppm. At 10 ppm, WA-AT-WB13R showed relatively high inhibition effects against C-1, X-1, and X-2. WA-PR-WB13R showed bactericidal effects against P-5, P-6 and X-2 at 10 ppm or higher concentrations. All the tested three nano-silver liquid showed bactericidal effects against all the tested plant pathogenic bacteria at concentrations of 25 ppm or higher. These results indicated the possible use of nano-silver liquid for the control of plant pathogenic bacteria.
Kwon, Soo Jeong;Roy, Swapan Kumar;Kim, Hye-Rim;Moon, Young-Ja;Yoon, Ki-Hong;Woo, Sun Hee;Boo, Hee Ock;Koo, Jin-Woog;Kim, Hag Hyun
KOREAN JOURNAL OF CROP SCIENCE
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v.62
no.3
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pp.259-274
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2017
Platycodon grandiflorum (Bell flower) is an important plant that has traditionally been used as herbal medicine for the treatment of cough, phlegm, sore throats, lung abscesses, chest pains, dysuria, and dysentery. The present study was initiated to investigate the feasibility of inducing shoot and root organogenesis in cultured explants of P. grandiflorum in a range of culture media and through use of various plant growth regulators (PGRs). The plantlets (Stem containing one node) were isolated and cultured on different concentrations of Murashige and Skoog (MS) medium supplemented with PGRs. We found that proliferation and elongation of shoots and roots could be achieved on 1/4 MS for P. grandiflorum with wild and green petals and on 1/8 MS for P. grandiflorum with double petals. The highest levels of development and elongation of adventitious shoots and roots were observed when petal explants were cultured on 1/4 MS (pH 3.8) supplemented with 5% sucrose. Increasing the agar concentration reduced shoot growth and rooting potential; nevertheless, the highest number of shoots and roots was observed on 0.6% agar. In the case of growth regulators, 1/4 MS supplemented with $1mg\;L^{-1}$ 6-benzylaminopurine (BA) was found to be best for shooting, although higher concentrations of BA tended to reduce shoot and root elongation. The highest number of shoots was achieved on $0.5mg{\cdot}L^{-1}$ thidiazuron (TDZ) from double petal explants grown on 1/8 MS. However, root and shoot elongation were found to decrease when TDZ concentrations were increased. Low concentrations of kinetin, naphthalene acetic acid, indole acetic acid, and 3-indole butyric acid induced shoot and root proliferation and elongation. Taken together, our study showed that low concentrations of PGRs induced the greatest root formation and elongation, showing that the optimal concentration of PGRs for shoot proliferation was species-dependent.
Polyclonal antisera against regional (abdominal and subcutaneous) fats were developed to reduce body fat in rats. Isolation and culture of abdominal and subcutaneous adipocytes of rats were performed for analyzing lactate dehydrogenase (LDH) concentration. At the level of 1:1,000 dilution, little antibody reactivity appeared in non-immunized serum whereas both of antisera against abdominal (AAb) and subcutaneous adipocyte plasma membrane proteins (SAb) had relatively strong reactivity till the level of 1:128,000 dilutions. Compared with regional fats, extremely low reactivities of AAb and SAb were detected with PMP of the organs (p<0.001). Both AAb and SAb were most strongly reacted with each adipocyte plasma memebrane proteins and showed statistically (p<0.01) higher cross-reactivities compared with non-immunized serum based on LDH analysis. In conclusion, these results may indicate that the present polyclonal antibodies against regional inedible adipocyte plasma membrane proteins are well developed and have safety in cross-reactivities with body organs.
A composite material was produced as an artificial bone substitute which is gradually degrAded and replaced by the regenerated natural bones after implantation. To detect the effect of the material on the cell's activity, the composite specimens were placed in MEMs and incubated at $37^{\circ}C$ for one week. Human uterus cervical cancer origin HeLa 3 cells and mouse subcutaneous origin L929 cells were cul- tured in the specimen dissolved MEMs for 5 days to investigate cytotoxicity via cell growth rates. ${Na_2}^{51}CrO_4$ solution was added to the media, to label the HeLa 53 cells, and the released amount of $^{51}Cr$ was measured by a $\gamma$-counter. On the cell growth investigation, no significant cytotoxic phenomena were revealed in both HeLa S3 and L929 cell cultures. On the released 51CR from the incubated HeLa 53 cells, no significant cell degeneration was observed from the composite embedded MEMs.
Background : Nowadays a lot of research is based on natural substances or materials world wide since many kinds of side effects are accompanied by anti tumor chemotherapy. In Chinese medicine, Dioscorea bulbifera L is widely used to treat many kinds of cancer, but in Korea it is rarely used. Therefore, we need to scientifically identify anti tumor effects of Dioscorea bulbifera L. Objective : We aimed to identify anti tumor effects of Dioscorea bulbifera L on the stomach cancer cells through molecular biological methods. Materials & Methods : We used AGS, a stomach cancer cell from American Type Culture Collection. We injected the boiled extract of Dioscorea bulbifera L 5 ul(sample 1), 10ul(sample 2) to cultured media(ml) for 0,6,12,18,24 hours. We measured the killing effect on stomach cancer cells through Tryphan blue exclusion test and suppressive effect on viability of stomach cancer cells via MTT assay. Results : Tryphan blue exclusion test showed that each test group killed more stomach cancer cells than the controlled group with a dosage-dependent, but not significantly. MTT assay showed that each test group had a more suppressive effect on viability of stomach cancer cells than the controlled group without a dosage-independent, but not significantly. The cell cycle analysis via flow cytometry showed that the test group extended cell cycle, and there was no peak in M phase, the number of sub G1, G0, G1 phase cells increased a little, but not significantly. Conclusion : This experiment showed that Dioscorea bulbifera L. has an anti-tumor effect, but not significantly. This is in vitro experiment and basic experiment on Dioscorea bulbifera L. We hope more progressive researches on Dioscorea bulbifera L. will be conducted and its anti tumor will be more accurately identified.
Background : Nowadays many researches about it s cure are going on world widely since cancer is one of the most human health threatening diseases. In Chinese and North Korean medicine, Duchesnea india(Audra.) Foche. is practically used to treat many kinds of cancer, but in Korea it is rarely used. So, we need to scientifically identify anti-tumor effects of Duchesnea india(Audra.) Foche. Objective : We are aimed to identify anti-tumor effects of Duchesnea india(Audra.) Foche. on the stomach cancer cells through molecular biologic methods. Material & Methods : We used AGS as stomach cancer cells from American Type Culture Collection. We added the boiled extract of Duchesnea india(Audra.) Foche. $5{\mu}l$(Sample I), $10{\mu}l$(Sample II) to cultural media(ml)for 0,6, 12, 24, 48 hours. We measured the killing effect on stomach cancer cells through Tryphan blue exclusion test and the suppressive effect on viability of stomach cancer cells via MTT assay. the quantitative RT-PCR was used to examine their effect on the revelation of Bcl-2, Bcl-XL, and Bax, which are genes related to apoptosis. We measured change of mitochondria membrane permeability and membrane potential via flow cytometry. Result : 1. The killing effect on stomach cancer cells showed that each test groups killed more stomach cancer cells than the control group with a time(6 hours later) and density dependent manner, which was statistical significance. 2. The suppressive effect on viability of stomach cancer cells showed that each test groups had more suppressive effects on viability of stomach cancer cells than the control group with a time(6 hours later), which was statistical significance. 3. In the test about the revelation of genes related to apoptosis, the revelation of Bcl-2 and Bcl-XL decreased with a density manner which was statistical significance. but the revelation of Bax was not changed with statistical significance. 4. As a result of this test, Duchesnea india(Audra.) Foche. caused apoptosis by decreasing the absorbance of mitochondria with statistical significance. and also induced apoptosis by decreasing the membrane potential of mitochondria. Conclusion : This experiment showed that Duchesnea india(Audra.) Foche. has anti-tumor effect with statistical significance. This is in vitro experiment and basic experiment on Duchesnea india(Audra.) Foche. We hope more progressive researchs on Duchesnea india(Audra.) Foche. will go on and its anti-tumor effects will be more practically identified.
Objective: We are aimed to identify anti-tumor effects of Curcuma longa L. on the stomach cancer cells through molecular biologic methods. Material & Methods: We used AGS as human stomach cancer cells obtained from American Type Culture Collection. The boiled extract of Curcuma longa L. $5{\mu}l$ (Sample I), $10{\mu}l$ (Sample II) was treated to cultural media(ml) for 0, 6, 12, 24, 48 hours. We measured the killing effect on stomach cancer cells through Trypan blue exclusion test and the suppressive effect on viability of stomach cancer cells via MTT assay. For identification of its anticancer mechanism, the revelation of Bcl-2, Bcl-XL, and Bax which are genes related to apoptosis using the quantitative RT-PCR, change of mitochondria membrane permeability and membrane potential via flow cytometry, the cycle of cell mitosis, caspase cleavage and annexin V staining were examined. Results: 1. showed significant killing effect on stomach cancer cell than the control group with a time(6 hours later) and density dependent manner, which was statistical significance. 2. Extract of Curcuma longa L. showed suppressive effect on viability of stomach cancer cells that each test groups had more suppressive effects on viability of stomach cancer cells than the control group with a time(6 hours later), which was statistical significance.(p<0.05) 3. In the test about the revelation of genes related to apoptosis, the revelation of Bcl-2 and Bcl-XL decreased with a density manner which was statistical significance. but the revelation of Bax was not changed with statistical significance. 4. Extract of Curcuma longa L. caused apoptosis by decreasing the absorbance of mitochondria with statistical significance, and also induced apoptosis by decreasing the membrane potential of mitochondria. 5. Extract of Curcuma longa L. destructed the cell cycle of cell mitosos. 6. Cell apoptosis was induced by extract of Curcuma longa L. certificated by method of caspase cleavage and annexin V staining. Conclusion: This experiment showed that Curcuma longa L. has anti-tumor effect with statistical significance. This is in vitro experiment and basic experiment on Curcuma longa L.. We hope more progressive research on Curcuma longa L. will go on and its anti-tumor effects will be more practically identified.
This study was designed to examine the factors affecting in fertilization and development of embryos in vitro, and to examine whether zone drilling by laser irradiation can improve the hatching rate of IVF embryos from DNA marker-proved Hanwoo. DNA markers related to marbling score were identified using DNA fingerprinting with Ml3 probe and restriction enzyme Hae III. Oocytes were aspirated from immature ovarian follicles using a combined method of rectal ovarian-palpation and transvaginal ultrasound-guidance(6.5MHz) under local anesthesia. The aspirated oocytes were washed twice with fresh D-PBS containing 5% FBS and were rewashed 4 to 5 times with TCM-199 containing 5% FBS. A morphological grade of I to IV was assigned to each oocyte. Data were analyzed using the GLM procedure of SAS. Sperm separation methods did not have any significant effect on cleavage or developmental abilities of IVF embryos. Significantly(P<0.05) higher cleavage rate was observed in embryos from GI(60.0%, 3/5), GII(69.2%, 18/26) and GIII(62.1%, 59/95) compared to embryos from GIV oocytes(36.2%, 25/69). And the developmental rate to blastocyst stage was higher(P<0.05) in embryos from GI(33.3%, 1/3) and GII oocytes(38.9%, 7/18) than those from GIII(16.9%,10/59) and GIV oocytes(4.0%, 1/25). There was no significant difference in development of IVF embryos to blastocyst by media for in vitro culture. Proportion of hatched blastocyst was significantly(P<0.05) higher in embryos received zona drilling by laser than those of non-drilled.
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