• Korean Journal of Weed Science
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• v.30 no.4
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• pp.380-389
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• 2010

Transgenic herbicide-resistant sweet potato plants [Ipomoea batatas (L.) Lam.] produced through a biolistic transformation were used in this study. The objective of this research was to find out a rapid and reliable assay method for confirming glufosinate-ammonium resistance. The techniques tested include whole-plant bioassay, one leaf bioassay, and leaf disk bioassay. Parameters investigated in this study were leaf injury and ammonium accumulation at 1 and 5 days after treatment of glufosinate-ammonium. In the leaf disk bioassay, leaf injury of the transgenic line 7171 was 1.9-fold less affected by glufosinate-ammonium than the wild type. The leaf injury of 7171 in one leaf and whole-plant bioassays was 59- and 92-fold less affected by glufosinate-ammonium, respectively, compared with that of the wild type. Leaf disk, one leaf, and whole-plant bioassays showed that ammonium accumulation of the 7171 was 2 to 20-, 4 to 43-, and 6 to 115-fold less affected by 0.5-5 mM glufosinate-ammonium than that of the wild type. All three bioassays successfully distinguished the resistance from the transgenic lines, but one leaf bioassay is the simplest and quickest. Leaf injury and ammonium accumulation were the same in leaves 1, 3, 5, 7, and 10 of 3 mM glufosinate-ammonium treated plants or nontreated plants. The one leaf bioassay was chosen as the standard procedure for future confirmation of resistance in transgenic sweet potato because it is a rapid and reliable assay.

• 한국균학회소식:학술대회논문집
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• 2016.05a
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• pp.25-25
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• 2016

Biological control has many advantages as a disease control method, particularly when compared with pesticides. One of the most important benefits is that biological control is an environmental friendly method and does not introduce pollutants into the environment. Another great advantage of this method is its selectivity. Selectivity is the important factor regarding the balance of agricultural ecosystems because a great damage to non target species can lead to the restriction of natural enemies' populations. The objective of this research was to evaluate the effects of several different bacterial isolates on the efficacy of biological control of soil borne diseases. White rot caused by Sclerotium cepivorum was reported to be severe disease of garlic and chive. The antifungal bacteria Burkholderia pyrrocinia CAB08106-4 was tested in field bioassays for its ability to suppress white rot disease. In field tests, B. pyrrocinia CAB08106-4 isolates suppressed white rot in garlic and chive, with the average control efficacies of 69.6% and 58.9%, respectively. In addition, when a culture filtrate of B. pyrrocinia CAB08106-4 was sprayed onto wounded garlic bulbs after inoculation with a Penicillium hirstum spore suspension in a cold storage room ($-2^{\circ}C$), blue mold disease on garlic bulbs was suppressed, with a control efficacy of 79.2%. These results suggested that B. pyrrocinia CAB08106-4 isolates could be used as effective biological control agents against both soil-borne and post-harvest diseases of Liliaceae. Chinese cabbage clubroot caused by Plasmodiophora brassicae was found to be highly virulent in Chinese cabbage, turnips, and cabbage. In this study, the endophytic bacterium Flavobacterium hercynium EPB-C313, which was isolated from Chinese cabbage tissues, was investigated for its antimicrobial activity by inactivating resting spores and its control effects on clubroot disease using bioassays. The bacterial cells, culture solutions, and culture filtrates of F. hercynium EPB-C313 inactivated the resting spores of P. brassicae, with the control efficacies of 90.4%, 36.8%, and 26.0%, respectively. Complex treatments greatly enhanced the control efficacy by 63.7% in a field of 50% diseased plants by incorporating pellets containing organic matter and F. hercynium EPB-C313 in soil, drenching seedlings with a culture solution of F. hercynium EPB-C313, and drenching soil for 10 days after planting. Soft rot caused by Pectobacterium carotovorum subsp. carotovorum was reported to be severe disease to Chinese cabbage in spring seasons. The antifungal bacterium, Bacillus sp. CAB12243-2 suppresses the soft rot disease on Chinese cabbage with 73.0% control efficacy in greenhouse assay. This isolate will increase the utilization of rhizobacteria species as biocontrol agents against soft rot disease of vegetable crops. Sclerotinia rot caused by Sclerotinia sclerotiorum has been reported on lettuce during winter. An antifungal isolate of Pseudomonas corrugata CAB07024-3 was tested in field bioassays for its ability to suppress scleritinia rot. This antagonistic microorganism showed four-year average effects of 63.1% of the control in the same field. Furthermore, P. corrugata CAB07024-3 has a wide antifungal spectrum against plant pathogens, including Sclerotinia sclerotiorum, Sclerotium cepivorum, Botrytis cinerea, Colletotrichum gloeosporioides, Phytophotra capsici, and Pythium myriotylum.

• Communications for Statistical Applications and Methods
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• v.3 no.3
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• pp.179-186
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• 1996

Bioequivanence models arise typically in bioassays when new preparations are compared against standard ones by means of responses on some biological organisms. Relative potency measures provide nice interpretations for such bioequivalence and their estimation constitutes the prime interest of such studies. A conditional quantile process based on the k-nearest neighbor method is proposed for this purpose. An alternative procedure based on Kolmogrov-Smirnov type estimator has also been considered along with. ARIC ultrasound data are analyzed as examples.

• BMB Reports
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• v.28 no.3
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• pp.227-231
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• 1995

In order to figure out the relationships between structural features and biological activity of the host-specific HC-toxin in maize, structurally related cyclic tetrapeptides, chlamydocin and CYL-2 were isolated, and their biological activities in maize were examined. Biological activities of preparations were determined by root growth inhibition and electrolyte leakage bioassays. Chlamydocin and CYL-2 showed toxicities to maize. However, the toxicities of these compounds were non-specific. Thus, the precise peptide ring structure of HC-toxin apparently does not play an important role in toxicity, while resistance of maize to HC-toxin is based on a precise ring conformation.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2003.10a
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• pp.140-140
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• 2003

• Biomedical Science Letters
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• v.15 no.2
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• pp.161-166
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• 2009

Human erythropoietin(EPO) is a glycoprotein that enhances red blood cell production by stimulating proliferation and differentiation of erythroid progenitor cells in the bone marrow. Patients with chronic kidney disease(CKD) suffer from anemia caused by reduced production of EPO in the kidney. Recombinant human EPO protein has been used successfully for the treatment of anemia associated with CKD. Recently, attention has been paid to the development of side effect of EPO, pure red cell aplasia(PRCA), in some patients with CKD. PRCA is a rare disorder of erythropoiesis that leads to a severe anemia due to an almost complete cessation of red blood cell production. EPO-related PRCA is caused by the production of EPO-neutralizing antibodies(Abs) that eliminate the biological activity of EPO as well as endogenous EPO in patients undergoing therapy. Since 1988, almost 200 cases worldwide have been reported with Ab-positive PRCA after receiving EPO therapeutics. The underlying mechanisms of the breaking of immune tolerance to self-EPO have been investigated. Modification of formulation, organic compounds of container closures, and route of administration has been suggested for the possible mechanism of increased immunogenicity of EPO. A number of assays have been used to detect Abs specific to EPO. These assays are generally grouped into two major categories: binding Ab assays and neutralizing Ab assays(bioassays). There are several types of binding Ab assays, including radioimmunoprecipitation assay, enzyme-linked immunosorbent assay, and the BIAcore biosensor assay. In vitro cell-based bioassays have been utilized for the detection of neutralizing Abs. Finally, the recent experience with anti-EPO Abs may have considerable implications for the future development and approval of EPO preparations. Also, considering that millions of patients are being treated with EPO, clinicians need to be aware of signs and consequences of this rare but severe clinical case.

• IMMUNE NETWORK
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• v.7 no.4
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• pp.203-208
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• 2007

Background: Angiogenesis mediated by VEGF constitutes a new target for anti-cancer therapy which has explored through different ways of intervention aiming at the blocking of the tumoral angiogenesis. In the present study, we developed the assays by which efficacies of anti-VEGF inhibitor candidates are evaluated at the various levels. Methods & Results: First, we developed two sandwich ELISAs using coated anti-VEGF Ab and soluble Flt-1 receptor fusion protein (sFlt-1/Fc). As low as 200 pg/ml of hVEGF diluted in human sera was detectable by these assays. In addition, we found that VEGF inhibitors ($2{\mu}g/ml$ of either anti-VEGF Ab or sFlt-1/Fc) completely block 5 ng/ml VEGF in these ELISAs. Subsequently, two bioassays, wound healing and HUVEC tube formation assays, revealed that anti-VEGF Ab $(1{\mu}g/ml)$ & sFlt-1/Fc Ab $(1{\mu}g/ml)$, or SU5416 (VEGFR tyrosine kinase inhibitor, $1{\mu}M$) prevents the activity of VEGF $(1{\sim}10ng/ml)$. Finally, secretion of MMP-9 by VEGF-stimulated macrophages was abolished by treatment of anti-VEGF Ab $(1{\mu}g/ml)$ in gelatin zymography. Conclusion: ELISAs together with bioassays developed in this study are appropriate for evaluation of the efficacy of inhibitors of VEGF.

• KSBB Journal
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• v.16 no.6
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• pp.547-553
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• 2001

Glycoprotein from the water extract of dried root barks of slippery Elm was investigated for its anticancer immunostimulating activity, The glycoprotein contained molecular weight 15,000 to 500,000 Da, total carbohydrates 55.8 to 72.1%), total uronic acid 30.0 to 30.5%, and total proteins 5.0 to 6.1%. The anticancer immunostimulating activities were examined for both in vitro bioassays such as immune cell proliferation assay, mixed lymphocyte reaction (MLR), direct mitogenicity, T-dependent antibody production, and in vivo bioassays such as septic shock test and anticancer activity test in B16 melanoma transplanted mouse model. In vivo assay, the glycoprotein at the concentration of 3 mg/kg showed the best result that median survival time increased to about 140% in contrast to control groups.

• Korean Journal of Organic Agriculture
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• v.22 no.2
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• pp.321-334
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• 2014

This study was conducted to identify plant growth promoting effects of native plant resources and medicinal plants. 65 kinds of plant extracts from 64 species were evaluated based on two rice(Oryza sativa) seedling bioassays for gibberellins and gibberellin-like substances. 12 extracts of Artemisia princeps stem and leaf, Cirsium japonicum var. maackii whole plant, Rhododendron mucronulatum branch and leaf, Phragmites communis stem, Coix lacryma-jobi var. mayuen whole plant, Lespedeza bicolor branch and leaf, Hydrangea serrata f. acuminata whole plant, Phlomis umbrosa whole plant, Glycyrrhiza uralensis Rhizome, G. uralensis stem and leaf, Angelica gigas root, and Cnidium officinale rhizome showed growth promotion of rice seedlings. Our results suggested that the parts of these plants could be the potential sources as farm-made liquid fertilizers for plant growth promotion.

• Mycobiology
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• v.31 no.3
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• pp.179-182
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• 2003

A total of 187 endophytic fungi were isolated from 11 plant species, which were collected from 11 locations in Korea. Their antifungal activities were screened in vivo by antifungal bioassays after they were cultured in potato dextrose broth and rice solid media. Antifungal activity against plant pathogenic fungi such as Magnaporthe grisea(rice blast), Corticium sasaki(rice sheath blight), Botrytis cinerea(tomato gray mold), Phytophthora infestans(tomato late blight), Puccinia recondita(wheat leaf rust), and Blumeria graminis f. sp. hordei(barley powdery mildew) was determined in vivo by observing the inhibition of plant disease development. Twenty(11.7%) endophytic fungi fermentation broths were able to control, by more than 90%, at least one of the six plant diseases tested. Among 187 liquid broths, the F0010 strain isolated from Abies holophylla had the most potent disease control activity; it showed control values of more than 90% against five plant diseases, except for tomato late blight. On the other hand, fourteen(7.5%) solid culture extracts exhibited potent disease control values of more than 90% against one of six plant diseases. The screening results of this study strongly suggested that metabolites of plant endophytic fungi could be good potential sources for screening programs of bioactive natural products.