• Korean Journal of Plant Tissue Culture
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• v.22 no.4
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• pp.207-211
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• 1995

Immature zygotic embryos from immature seeds of Wasabia japonica (cv Dalma) were isolated and cultured on modified MS medium supplemented with 2,4-D, IAA, and BA. Immature zygotic embryos were classified into torpedo shape and cotyledon stage. The highest rates of callus formation were obtained of 1.0mg/L IAA(torpedo stage, 90.0%)and 1.0mg/L 2,4D plus 0.1mg/L BA(cotyledany stage,84.3%). Somatic embryos after 60 days of culture. These numerous somatic embryo could be seperated and subcultured on the same media for further propagation. After 90 days of culture, most somatic embryos were developed well organized embryos which were able to produce into whole plants.

• Journal of the Korean Society of Tobacco Science
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• v.21 no.1
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• pp.10-16
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• 1999

Leaves harvested were separated with visual characters into 2 classes such as immature and mature leaves. In the curing process, the prolonged yellowing treatment during yellowing stage was automatically controlled at the different stalk position, and condition of curing process after this period was all the same with conventional ones. In case of prolonged yellowing in immature leaves, increase of price per kg reached to 8 % compared with those of conventional ones. In physical properties, filling capacity and shatter index was decreased with the degree of maturity, and it was equal level in filling capacity of immature leaves between curing method, while shatter index was decreased in prolonged yellowing treatment than that of conventional ones. There was no difference in chemical components between immature leaves of prolonged yellowing and conventional ones. As to the prolonged yellowing of immature leaves, there was decreased in citric and malic acid contents of the nonvolatile organic acids, and it was equal level in all higher fatty acids content of leaves cured by prolonged yellowing treatment compared with in that of conventional curing method. The contents of key compounds such as solanone, damascenone, damascone in the essential oil were lower in prolonged yellowing of immature leaves than those of mature leaves cured by conventional ones.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2005.05a
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• pp.199-200
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• 2005

• Journal of Life Science
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• v.11 no.4
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• pp.311-315
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• 2001

To identify the effects embryo developmental stage and gelrite concentration on plant regeneration in seed culture of rice, mature and immature seeds of rice were cultured on the $N_{6}$ medium supplemented with2 mg/$\ell$ 2.4-D and different levels of gelrite(0.2~1.0%). The calli formed immature embryos were produced more plants than those from mature embryos. The maximum frequency of plant regeneration was achieved in the culture of the calli of immature embryos which was harvested at the 21$^{th}$ day after pollination. The plant regeneration on the medium with gelrite was more accelerate than that on the medium with agar. The highest frequency(55%) of plant regeneration was obtained from the calli transferred to the medium with 6g/$\ell$ gelrite.

• Animal Systematics, Evolution and Diversity
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• v.18 no.2
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• pp.213-217
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• 2002

The present paper is a part of the study on the immature stages of genus Tipula in Korea. It describes and illustrates each immature stage of Tipula (Yamatotipula) latemurginata from egg to pupa.

• Korean Journal of Plant Tissue Culture
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• v.21 no.5
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• pp.293-297
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• 1994

In order to induce immature pollen derived plants, anthers of Ranunculus japonicus Thunb. were cultured on Murashige and Skoog's medium supplemented with various combinations of auxins and cytokinins. The combinations of NAA and BA were more effective than those of 2,4-D and kinetin in the formation of calli and embryos. Up to 5t5% of the anthers cultured on medium containing 0.5 mg/L NAA and 1.0 mg/L BA gave rise to plantlets. The most suitable stage for anther culture in the induction of calli and/or embryos from immature pollens was at the uninucleate and early binucleate stage (3 days before anthesis). Immature pollens developed into embryos by repeated division of the vegetative nucleate after 60days of culture.

• Journal of the Korean Wood Science and Technology
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• v.50 no.4
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• pp.272-282
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• 2022

The essential oil extracted from Citrus × natsudaidai (Yu. Tanaka) Hayata peels is known to have various biological properties. However, the chemical composition of essential oil is influenced by the ripening stages of fruits, which then affects related biological activities. This study investigates the antioxidant activities of essential oils extracted from Citrus × natsudaidai peels at different ripening stages (immature, mature, and overripe). The essential oils were extracted using the hydro-distillation method. As a result of gas chromatography-mass spectrometry (GC-MS) analysis, d-limonene was dominant and was increased as matured. However, 𝛄-terpinene was decreased. The antioxidant properties and their total phenolic content (TPC) were influenced by the ripening stages. The TPC was highest in the immature stage of essential oil (1,011.25 ± 57.15 mg GAE/100 g). 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity was excellent in the immature stage (EC₅₀ = 15.91 ± 0.38 mg/mL). 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity was superior in overripe stage (EC₅₀ = 20.43 ± 0.37 mg/mL). The antioxidant activity measured using ferric reducing antioxidant power (FRAP) assay showed higher values for the essential oils in immaturity (1,342.37 ± 71.07 mg Fe²⁺/100 g). Comprehensively, the essential oil in the immature stage showed the best antioxidant activity. Finally, knowing the chemical composition and antioxidant activity at different ripening stages will provide data for selecting the right fruit.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.336-342
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• 1994

Changes in physicochemical characteristics were investigated for immature barley kernels roasted at $160{\sim}220^{\circ}C$ for $1{\sim}12$ min. Only small differences in chemical constituents including starch, protein, fat, ash, total dietary fiber, and ${\beta}-glucan were observed between immature and mature barley kernels. The amounts of 75% ethanol-soluble sugars and amino acids present in immature barley kernels were considerably higher than those in mature kernels, and gradually decreased in the process of roasting. Of free sugars, sucrose, raffinose, glucodifructose($GF_{2}$) and maltose were reduced by roasting. Glucose and fructose, simple reducing sugars, decreased at the early stage of roasting, followed by a slight increase at the later stage. Starch and nitrogen contents decreased slowly, while TDF(total dietary fiber) had a tendency to increase slightly. Stacking volume of immature barley kernels increased markedly, especially at the higher temperatures. L value of immature barley decreased throughout roasting, and a, b values increased at the early stage of roasting but b value decreased with continued roasting. The degree of roasting was strongly affected by the roasting temperature. Darkness of immature barley kernel, depending on the degree of roasting, was highly associated with concentrations of brown pigments extracted from roasted immature barley kernels.

• Journal of Embryo Transfer
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• v.13 no.2
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• pp.191-197
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• 1998

Immature nocytes and in VitrO matured Oocytes collected from the slaughtered Korean cattle were frozen slowly with 10% ethylene glycol+5% polyvinyl pyrolidine+0.05M trehalose (l0EPT), 10% ethylene glycol+5% ficoll+0.05M sucrose (1OEFS), or 10% ethylene glycol+5% ficoll+0.05M trehalose (l0EFT) by cell freezer (experiment 1). And also,They were ultra-rapidly frozen with 30% ethylene glycol+10% polyvinyl pyrolidine+0.5M trehalose (3OEPT) or 30% ethylene glycol+18% ficoll+0.5M sucrose (3OEFS) using electron microscope grid (experiment 2). In experiment 1, the cleavage rate was 23.0% when immature oocytes were frozen slowly using various cryoprotectants descrihed above, and 5.1% of cleaved oocytes developed to over morula stage after in Vitro fertilization (IVF). There were no significant differences among these groups. When matured oocytes were frozen slowly, the total cleavage rate was 19.7%, and over morula stage was 3.2%. lOEPT (4.8%) and EFS (4.4%) were slightly more effective than l0EFT (0.0%) for development in vitro. Only in l0EFT treated group, immature oocytes have higher developmental capacity than matured ones, when they were frozen slowly and IVF after thawing. In experiment 2, oocytes were ultra-rapidly frozen using the electron microscope grid with two kind of cryoprotectants described above. In immature oocyte group, the cleavage rate was 13.9% and 5.8% of cleaved oocytes developed to over morula stage after IVF, and in matured group, 25.7 and 7.6%, respectively. There were no significant differences between two kind of cryoprotectants, but in ultra-rapid freezing using electron microscope grid, the efficiency is slightly higher in matured oocyte group.

• Journal of Embryo Transfer
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• v.26 no.3
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• pp.201-207
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• 2011

The present study was performed to investigate the survival and subsequent embryonic developmental rate of immature and mature oocytes after vitrification and pronuclear stage embryos after slow-freezing and vitrification. We have also tried to examine the dependency of concentrations (7.5, 15%) and exposure time (5, 10, 20 min) of ED cryoprotectant on developmental rate of pronuclear stage embryos. The developmental rates of 2-ce1l and blastocyst embryos at mature oocytes were significantly (p<0.05) higher than immature oocytes. After slow freezing, vitrification and thawing of pronuclear stage embryo, the survival and developmental rates of blastocysts and hatched blastocysts were significantly (p<0.05) higher after vitrification than after slow-freezing. On contrary, the developmental rates of 2-cell embryos were significantly (p<0.05) higher after slow freezing than after vitrification. The cryopreservation methods of pronuclear stage embryos vitrified by exposed to 7.5% ED solution for 5 minutes was significantly (p<0.05) higher than other experimental group. The results of our study suggest 1hat the developmental rates of mature oocytes have been more successful than immature oocytes during vitrification. Vitrification was more efficient than slow freezing in case of pronuclear stage embryos. The effective cryopreservation method of pronuclear stage embryos was vitrified by exposed to 7.5% ED solution for 5 minutes.