• Korean Chemical Engineering Research
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• v.58 no.1
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• pp.21-28
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• 2020

The stem extract from Pyrus serotina var has natural antioxidant ability, but the extraction method does not result in a soluble compound in cosmetic formulations. This study investigated the cosmetic efficacy of the Pyrus serotina var stem extract and its epidermis permeation ability when combined with polymer micelles and a cell penetrating peptide. The total concentration of polyphenol compounds was determined to be 103.1644 ± 1.38 mg/g in the ethanol extract and 78.97 ± 1.45 mg/g in the hydrothermal extract. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging effects were 55.94 ± 0.22% in the ethanol extract at 1,000 mg/L. Superoxide dismutase (SOD) activity rates were 104.05 ± 3.28% in the ethanol extract at 62.5 mg/L. The elastase inhibition rate was 67.21 ± 2.72% in the ethanol extract at 1,000 mg/L. An antimicrobial effect was observed in the Propionibacterium acnes strain. In the epidermal permeability experiment, it was confirmed that formulation of the polymer micelle containing the Pyrus serotina var stem extract and cell penetrating peptide (R6, hexa-D-arginine) showed small particle size and much better skin permeability. The cumulative amount of total Pyrus serotina var stem extract that penetrated to the skin over time increased over 24 hours in three formulations. The three formulations showed 51.61 ㎍/㎠ (Formulation 0), 75.97 ㎍/㎠ (Formulation 1) and 95.23 ㎍/㎠ (Formulation 2) skin penetration, respectively. Therefore, it was confirmed that the ethanol extracts of Pyrus serotina var stem showed good cosmetic efficacy and excellent epidermis permeation ability when combined with a polymer micelle and cell penetrating peptide. Thus, this extract has the potential to be used as a safe and natural cosmetic material in the future.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.4
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• pp.582-586
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• 1995

The effects of cultural temperature and nutritional components on the production of ethanol using juice of Pyrus serotina as the substrate for Saccharomyces cerevisiae ATCC 4124 were studied. After anaerobic cultivation in 5L flask of a defined pear juice at 2$0^{\circ}C$, ethanol concentration of 11.5%(v/v) could be obtained. The addition of a small amount of K2S2O5 was essential for the successful production of ethanol. Ethanol concentration could be further enhanced by supplementing a small of various complex nitrogen sources. When 0.05% of yeast extract and 0.05% of (NH4)2HPO4 were added to a defined medium, ethanol concentration obtained after 7 day cultivation at 2$0^{\circ}C$ was 12.3%.

• Journal of the Korean Applied Science and Technology
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• v.36 no.3
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• pp.685-699
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• 2019

Antioxidant, antibacterial, and skin penetration tests were conducted to investigate the skin absorption of Pyrus serotina var leaf extracts using polymer micelles and their applicability to cosmetic ingredients. Total polyphenol content was found to be $118.83{\pm}9.39mg/g$ in Pyrus serotina var leaf ethanol extract and $106.89{\pm}4.45mg/g$ in Pyrus serotina var leaf hydrothermal extract. The DPPH radical scavenging activity was found to be the highest radical scavenging activity of $74.39{\pm}7.48%$ of the Pyrus serotina var leaf ethanol extract at the concentration of 500 mg/L. The SOD-like activity was $91.62{\pm}0.43%$, the highest value at the concentration of 1,000 mg/L in the hydrothermal extract. After the experiment, antioxidation, wrinkle improvement and whitening activity were confirmed, and the Pyrus serotina var leaf extract was highly likely to be realized as antioxidant and antibacterial material. In the skin penetration experiment with the Pyrus serotina var leaf ethanol extract, the permeation amount of total accumulated tannic acid was found to be Formulation 2 ($55.45{\mu}g/cm^2$), Formulation 1 ($46.43{\mu}g/cm^2$), Formulation 0 ($34.36{\mu}g/cm^2$). In the liposome's skin penetration experiment containing pear leaf hydrothemal extract, the total amount of accumulated tannic acid permeation was found to be Formulation 5 ($75.01{\mu}g/cm^2$), Formulation 4 ($64.01{\mu}g/cm^2$) and Formulation 3 ($36.60{\mu}g/cm^2$). Through this study, we confirmed the possibility of antioxidant and wrinkle effects of Pyrus serotina var leaf extract. In addition, as a result of skin penetration through the production of polymer micelles and liposome containing Pyrus serotina var leaf extract, It will be more usable in cosmetic industry.

• Mycobiology
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• v.34 no.3
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• pp.151-153
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• 2006

Rhizopus soft rot caused by Rhizopus stolonifer occurred on pears (Pyrus serotina) in the Jinju City Agricultural Products Wholesale Market in Korea from 2004 to 2005. The infection usually started from wounds due to cracking at harvest time. The lesions started as water-soaked, rapidly softened, then gradually expanded. The mycelia grew vigorously on the surface of the fruits and formed stolons. Colonies on potato dextrose agar at $25^{\circ}C$ were white cottony to brownish black. Sporangia were globose, black and $90{\sim}120\;{\mu}m$ in size. Sporangiophores were light brown and $480{\sim}2600{\times}12{\sim}18\;{mu}m$ in size. Sporangiospores were globose to oval, brownish, streaked, and $8{\sim}14{\times}6{\sim}10\;{\mu}m$ in size. Columella were light brownish gray, hemispherical and $70{\sim}80\;{\mu}m$ in size. On the basis of these symptoms, mycological characteristics and pathogenicity tests on host plants, the fungus was identified as Rhizopus stolonifer (Ehrenb.) Vuill. This is the first report of rhizopus soft rot on pear (P. serotina) caused by R. stolonifer in Korea.

• Korean Journal of Organic Agriculture
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• v.21 no.3
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• pp.373-380
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• 2013

A severe pink mold rot on matured asian pear (Pyrus serotina Rehder) fruit occurred in the organic farmers' orchard in Jinju, Korea in October, 2012. Decay of pear fruit appeared as a softened water-soaked symptom that was easily punctured by pressure. Later pink mycelium appeared on the surface of pear fruit and produced a mass of powdery pink conidia spores. Optimum temperature for mycelial growth of T. roseum was $25^{\circ}C$. Conidia showed hyaline, smooth, 2-celled, thick-walled with truncate bases, ellipsoidal to pyriform, and characteristically held together zig-zag chains and $10{\sim}22(34){\times}6{\sim}10(12){\mu}m$ in size. Conidiophore was erect, colorless, unbranched type, and 4-5 ${\mu}m$ width. On the basis of mycological characteristics, pathogenicity test, and molecular identification with the ITS region, the causal fungus was identified as Trichothecium roseum (Pers.) Link ex Gray.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2002.11a
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• pp.101.1-101
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• 2002

• Research in Plant Disease
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• v.12 no.3
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• pp.164-167
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• 2006

Potential factors favoring black stains during fruit development in Pyrus serotina was investigated. Black stain occurred from young fruit till harvest. The color of the affected fruits in early stage was black or light reddish brown, but turned to light brown over time. Fruit bags with lower light transmission and inner bags with poor aeration stimulated the symptoms, and high water permeability of the bags increased the black stain. Much rain and/or poor light transmission and aeration within the canopies also favored the occurrence of black stain. Diminution of pathogenic fungi density by lime sulfur was more effective than the canopy spray of fungicide for the prevention of black stain.

• Food Science of Animal Resources
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• v.29 no.2
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• pp.157-163
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• 2009

This study was conducted for the isolation, purification, and characterization of a protease from Korean pear, to see its proteolytic activity on chicken actomyosin and to find the optimum pH and temperature of activity on chicken actomyosin. The protease was isolated from crude extract of Korean pear by ammonium sulfate precipitation. Further purification was done by DEAE-Sepharose ion-exchange chromatography, Mono-Q and Mini-Q column chromatography. The purified enzyme gave a single protein band on SDS polyacrylamide gel electrophoresis and the molecular weight was found to be 38 kDa. The specific activity of purified enzyme was 34,907 unit/mg with 25 fold purification and the yield was 2%. The purified enzyme incubated with chicken actomyosin showed high activity. The optimum pH and temperature for enzyme activity on chicken actomyosin were 6.5 and $70^{\circ}C$, respectively. A protease was purified from Korean pear for the first time and characterized. It was found to be promising for meat tenderization.

• Journal of the Korean Institute of Landscape Architecture
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• v.22 no.4
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• pp.95-117
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• 1995

This study was carried out to investigate Korean native trees in the America landscape through arboretums, the plant inventory of America, computer files for accessions from Korea, source lists of plants and seeds, and seed and plant nursery company. The results were as follows; 1. Korean native trees introduced in America and Canada were 119 species, 116 species were being cultivated in arbrids were being sold in nurseries, new cultivars were selected from 32 species, and hybrids were bred from 5 species. 2. Abies koreana, Malus baccata, and Stewartia koreana were being cultivated in many arboretums and sold in many nurseries. Also there were new hybrids as well as new cultivars. 3. 25 species including Albizzia julibrissin were being cultivated in many arboretums and sold in many nurseries. Also there were new hybrids. 4. Ilex integra and Ilex rotunda were being cultivated in many arboretums and sold in many nurseries. There were no new cultivars, but there were new hybrids. 5. 44 species including Abies holophylla were being cultivated in many arboretums and sold in many nurseries. There were no new cultivars or hybrids. 6. Populus tremula var. davidiana was being cultivated in many arboretums. There were new cultivars of 'Erecta', 'Gigas', 'Pendula', but no new hybrids. They were not sold by any nurseries. 7. 41 species including Abies nephrolepsis were being cultivated in many arboretums. But they were not sold by any nurseries. They didn't have any new cultivars or hybrids. 8. Diospyros kaki 'Kyungsan Bansi', Elaeocarpus sylvestris var. ellipticus, and Pyrus serotina 'Dankae' were not being cultivated in arboretums in America but some nurseries were selling those species as well as new cultivars. 9. Only 3 species (Berchemia berchemiaefolia, Carpinus eximia, and Chionanthus retusus var. coreana which are native Korean plants) were not introduced in America or Canada.

• Journal of the Korean Institute of Landscape Architecture
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• v.23 no.3
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• pp.144-154
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• 1995

The fruit color characteristics and persisting period of deciduous woody landscape plants were investigated through the field survey in Suwon region from January 1, 1992 to March 20, 1993. The summary of the study results was as follows; The total fruit color persisting period was about 320 days from May 1, 1992 when Prunus mume was beginning of fruit coloring, to March 20, 1993 when the fruits of Platanus occidentalis and platanus X acerifolia were persisting. And the plants of fruit persisting period over 60 days after leaf falling were Vibumum erosum, Ilex serrata, Ilex verticillata 'Christmas Cheer', Platanus X acerifolia, Platanus occidentalis, Berberis thunbergii 'Atropupurea', Ligustrum obtusifolium. According to the KBS standard color number, 52.6% of of the fruit color were red, 18.9% yellow, 11.6% black, green 9.5%, white 2.1%, violet 1.1%, and red is followed black 4.2%. Evodia daniellii, Ilex verticillata 'Christmas Cheer', Ilex serrata, Ginkgo biloba, Lindera obtusiloba, and Lindera erythrocarpa should be planted male and female species together for fruits. We got the new information on the fruit color characteritics and persisting period of Malus 'Hopa', Malus 'Almey', Malus 'Pioneer X', Acer rubrum, Malus prunifolia, Pyrus serotina, Berberis thunbergii 'Atropurpurea', Vibumum rhytidophyllum, Rosa spp. Vitis vinifera, Vaccinium angustifolium, Ilex verticillata 'Christmas Cheer', Magnolia stellata, Aronia arbutifolia, Sorbus alnifolia, Lonicera japonica var. aueroreticulta, and Ligustrum X vicaryi. And we need to introduce new cultivars of woody landscape plants including Malus spp, Berberis spp, Sorbus alnifolia yellow autumn leaf clone etc. for the better planting design. The fruit persisting period of woody landscape plants studied by fruit name was that sorosis 276 days, samara 155 days, legume 153 days, hip 133 days, pome was 124 days, drupe 92 days, berry 73 days, capsule 67 days, follicle 55 days and nut 52 days respectively.