• Journal of the Korean Wood Science and Technology
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• v.23 no.2
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• pp.32-36
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• 1995

A study was conducted to evaluate the dynamic mechanical properties (modulus of elasticity, resonant frequency and interanal friction) of compression wood in Pinus densiflora. Vibration method was used for estimation of dynamic modulus of elasticity and the values were compared to those of static bending modulus of elasticity. The results obtained are as follows: 1. The dynamic modulus of elasticity of compression wood decreased, whereas that of normal wood increased, with increasing specific gravity. 2. The resonant frequency of compression wood decreased, whereas that of normal wood increased, with increasing specific gravity. 3. The internal friction of compression wood increased with increasing specific gravity. 4. The correlation coefficients between dynamic and static moduli of elasticity in compression and normal woods were high.

• Journal of the Korean Wood Science and Technology
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• v.24 no.2
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• pp.81-93
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• 1996

To elucidate the structure of procyanidin in Korean red pine (Pinus densiflora S. et Z.), bark, the extractives were extracted with acetone-water mixture(7:3, v/v) from inner bark of Korean red pine. The extracts separated three fractions which were extracted by liquid-liquid extraction. The extracting solvents were chloroform and ethyl acetate and water. The part of ethylacetate soluble was chromatographed by liquid chromatography. The ethylacetate soluble portion yielded four natural procyanidin dimers, two known epicatechin-($4{\beta}{\rightarrow}6$)-catechin, catechin-($4{\alpha}{\rightarrow}8$)-catechin and two unknown catechin-($4{\beta}{\rightarrow}6$)-catechin and conformational isomer of epicatechin-($4{\alpha}{\rightarrow}6$)-catechin. The additional catechins was also isolated. The structures of these procyanidins were elucidated by their $^{13}C$-NMR spectra.

• Mycobiology
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• v.34 no.4
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• pp.191-195
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• 2006

This study was conducted to investigate the different effects of ectomycorrhizal fungal (ECMF) species on the growth of seedlings of Pinus densiflora, and the effects of ECMF diversity on plant productivity. A total of five species of ECMF were isolated from root tips of pine seedlings collected from Mt. Songni and used as inocula. Pots containing pine seedlings were inoculated with either a single ECMF species or a mixture of five ECMF species. All of the seedlings formed ECM on their roots except for the control plants. The pine seedlings' growth responses varied by the different ECMF species. Also, pine seedlings inoculated with a mixture of five ECMF species showed the highest growth response. The results of the study suggest that the colonization of diverse species of ECMF will increase plant productivity, and the selection of suitable ECMF species could be an important factor for plant growth.

• Journal of the Korea Furniture Society
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• v.14 no.1
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• pp.11-20
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• 2003

Wood cell-wall modification with acetic anhydride, lumen filled with styren monomer and methyl methacrylate, and a combination of these two treatments were studied for their effectiveness for dimensional stability. Compared to those of untreated Pinus densiflora Sieb. et Zucc and sole acetylated red pine, The combination of acetylation and impregnation with methy methacrylate greatly reduced water absorption, increased ASE to the best and gave better bending strength and compression strength.

• Korean Journal of Medicinal Crop Science
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• v.13 no.2
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• pp.110-114
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• 2005

Extracts from sawdust of Pinus densiflora were showed antifungal activity against Lentinula edodes. It was extracted by hot water and then successively extracted by n-hexane, ethyl acetate, and methanol. The yields of the n-hexane-soluble, ethyl acetatesoluble, methanol-soluble and methanol-insoluble fractions of water extracts were 8.2%, 10.6%, 32.0%, and 49.2%, respectively. The ethyl acetate-soluble fraction showed the greatest antifungal activity against L. edodes: 41.5% inhibition at 1,000 ppm. However, there were not significant differences of antifungal activities between n-hexane-soluble fraction and methanol-soluble fraction at a concentration of 1,000 ppm. The hot water extracts showed 23.5% of antifungal activity against L. edodes at a concentration of 1000 ppm. The four antifungal compounds were separated from ethyl acetate fraction by thin layer chromatography.

• Mycobiology
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• v.41 no.2
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• pp.77-81
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• 2013

This study aimed to investigate differences in ectomycorrhizal (ECM) fungal communities between disturbed sites and undisturbed old forest sites. ECM root tips of Pinus densiflora were collected from 4 sites disturbed by human activities and 3 undisturbed old forest sites adjacent to the disturbed sites. Results in this study showed that the number of ECM root tips, species diversity, and number of species were significantly higher in the disturbed sites than in the undisturbed sites, suggesting that the ECM fungal community structure was affected by the degree of disturbance.

• The Korean Journal of Mycology
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• v.48 no.2
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• pp.117-124
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• 2020

In this study, we isolated endophytic fungi from the conifer leaves of Pinus densiflora inhabiting Mt. Gyehwasan in Korea. We identified the isolated fungal strains based on their morphological characteristics and phylogenetic analysis using DNA sequences of the internal transcribed spacer, small subunit rDNA, large subunit rDNA, and β-tubulin region. In the process of this study, we confirmed two endophytic fungi that have not been recorded previously in Korea, Lophiostoma macrostomum and Pestalotiopsis lespedezae. In this report, we described the morphological characteristics of these fungal strains and the results of their molecular analysis.

• Korean Journal of Plant Resources
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• v.12 no.1
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• pp.10-19
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• 1999

The water status of Pinus densiflora and P. koraiensis was observed after the treatment of simulated acid rain for every month August 1997 to March 1998. Both of the species showed increase of dry weight, water saturation deficit and epidermis transpiration after treatment of simulated acid rain (pH 3.5) for first three months. On the contrary, water content was decreased in both the species after three month of simulated acid rain treatment. The effect of simulated acid rain, however, became weaker after that and no big difference was observed after seven month of treatment. Water potential of the leaf of both species became lower than that of the control(pH 5.6) after seven month treatment of simulated acid rain. The cuticle layers of the epidermis and florins ring were damaged seriously and the size of the gap between stomata became bigger after the treatment of simulated acid rain.

• The Korean Journal of Ecology
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• v.8 no.4
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• pp.197-200
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• 1985

The relations of crown width and DBH for Pinus densiflora, Pinus rigida, Pinus koraiensis, and Ginkgo biloba were accomplished to estimate the level of crown competition. Measurements of the relations revealed that crown width and DBH were highly correlated for the same species. Also it seems that these relations are independent of age and site quality. The results of regression analysis were as follow: P. densiflora, Y=0.3477X+0.3828 r=0.95 p. rigida, Y=0.3537X+0.1645 r=0.95 P. koraiensis, Y=0.2895X+0.6310 r=0.92 G. biloba, Y=0.4360X+0.0995 r=0.90 The significant differences between G. biloba and pine species seems due to their structural differences of crown formation according to tree species. As results of computing Maximum Crown Area and Crown Competition Factor as indices of crown competition, they indicated that P. densiflora would grow better under the natural conditions.

• Natural Product Sciences
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• v.16 no.1
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• pp.10-14
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• 2010

Phytochemical examination of the barks of Pinus densiflora Siebold et Zuccarini has led to the isolation of one phenylpropanoid, one lignan, one flavonoid, one flavan 3-ol and two procyanidins : 4-O-$\beta$-D-glucopyranosyl-p-coumaric acid (1), 2,3-dihydro-2-(4-methoxy)-7-hydroxy-3-hydroxymethyl-5-(3-hydroxy propyl)-benzofuran 3-O-$\alpha$-D-glucopyranoside (2), taxifolin 3'-O-$\beta$-D-glucopyranoside (3), (+)-catechin (4), procyanidin B1 (5) and epicatechin-($4{\beta}$-8)-catechin-($4{\alpha}$-8)-catechin (6). Among them, Compound 4, 5 and 6 showed potent anti-oxidative activities and these anti-oxidative activities were significantly different compared with ascorbic acid as positive control.