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Ingyu Choi - One of the best experts on this subject based on the ideXlab platform.

  • Biomass characteristics and ethanol production of yellow poplar (Liriodendron tulipifera) treated with slurry composting and biofiltration liquid as fertilizer
    Biomass and Bioenergy, 2012
    Co-Authors: Ho-yong Kim, KI SEOB GWAK, Su-yeon Lee, Hanseob Jeong, Keun-ok Ryu, Ingyu Choi
    Abstract:

    Abstract The main purpose of this study was to examine the influence of slurry composting and biofiltration liquid fertilizer (SCBLF) treatment on the biomass characteristics and ethanol production of yellow poplar ( Liriodendron tulipifera ). The relative growth rate, biomass production, and chlorophyll content were significantly increased by SCBLF treatment. Nutrients in SCBLF caused an increase in chlorophyll content, which led to improved biomass production (3.4%) and increased glucose content (9.8%). Organosolv and dilute acid pretreatment for ethanol production were carried out, and the pretreatment processes were conducted at the same solid to liquid ratio (1:10), reaction temperature (150 °C), preheating time (40 min), and residence time (10 min). The water insoluble solid recovery of organosolv pretreatment with 1% sulfuric acid on SCBLF-treated yellow poplar was the lowest (46.7%). Exchangeable cation contents in SCBLF enhanced the pretreatment effect by reducing glucose degradation. Simultaneous saccharification and fermentation processes were carried out to determine the ethanol production of the pretreated biomass. Organosolv pretreatment with 1% sulfuric acid on SCBLF-treated biomass resulted in the highest ethanol production (39.68 g L −1 ) and yield based on initial weight (18.66%).

  • investigation of physicochemical properties of biooils produced from yellow poplar wood Liriodendron tulipifera at various temperatures and residence times
    Journal of Analytical and Applied Pyrolysis, 2011
    Co-Authors: Kwang Ho Kim, Ingyu Choi, Soo-min Lee, Hwanmyeong Yeo, In Yong Eom, Donha Choi, Joonweon Choi
    Abstract:

    Abstract Fast pyrolysis of yellow poplar wood ( Liriodendron tulipifera ) was performed under different temperature ranges and residence times in a fluidized bed reactor to maximize the yield of biooil. In this study, the pyrolysis temperature ranged from 400 °C to 550 °C, and the residence time of pyrolysis products was controlled between 1.2 and 7.7 s by inert nitrogen gas flow. The results revealed that the distribution of thermal degradation products (biooil, biochar, and gas) from the woody biomass was heavily influenced by pyrolysis temperature, as well as residence time. The highest yield of biooil was approximately 68.5 wt% (wet basis), with pyrolysis conditions of 500 °C and 1.9 s of residence time. Water content of the biooils produced at different temperatures was 25–30 wt%, and their higher heating values were estimated to be between 15 MJ/kg and 17 MJ/kg. Using GC/MS analysis, 30 chemical components were identified from the biooil, which were classified into 5 main groups: organic acids, aldehydes, ketones, alcohols, and phenols. In addition, biochar was produced as a co-product of fast pyrolysis of woody biomass, approximately 10 wt%, at temperatures between 450 °C and 550 °C. The physicochemical features of the biochar, including elemental analysis, higher heating values, and morphological properties by SEM, were also determined.

  • effects of dilute acid pretreatment on enzyme adsorption and surface morphology of Liriodendron tulipifera
    Journal of the Korean wood science and technology, 2011
    Co-Authors: Byeongcheol Min, KI SEOB GWAK, Joonweon Choi, Bon-wook Koo, Hwanmyeong Yeo, Ingyu Choi
    Abstract:

    In this study, dilute acid pretreatment of Liriodendron tulipifera was performed for enzymatic hydrolysis. As the pretreatment temperature was increased, enzymatic hydrolysis and enzyme adsorption yield also increased. The highest enzymatic hydrolysis yield was 57% (gig) and enzyme adsorption was 44% (gig). Enzymatic hydrolysis yield was determined with weight loss of pretreated biomass by enzyme, and enzyme adsorption was a percentage of enzyme weight attaching on pretreated biomass compared with input enzyme weight. When L. tulipifera was pretreated with 1% sulfuric acid at 160℃ for 5 min., hemi-cellulose was significantly removed in pretreatment, but the lignin contents were constant. Other changes in surface morphology were detected on biomass pretreated at 160℃ by a field emission scanning electron microscope (FESEM). A large number of spherical shapes known as lignin droplets were observed over the entire biomass surface after pretreatment. Hemicellulose removal and morphological changes improved enzyme accessibility to cellulose by increasing cellulose exposure to enzyme. It is thus evidence that enzyme adsorption is a significant factor to understand pretreatment effectiveness.

  • evaluation of oxalic acid pretreatment condition using response surface method for producing bio ethanol from yellow poplar Liriodendron tulipifera by simultaneous saccharification and fermentation
    Journal of the Korean wood science and technology, 2011
    Co-Authors: Hyeyun Kim, Jae-won Lee, Thomas W Jeffries, Ingyu Choi
    Abstract:

    이 연구에서는 백합나무(Liriodendron tulipifera)를 옥살산으로 전처리한 시료로부터 에탄올 생산 가능성을 조사하고, response surface methodology(RSM)를 도입하여 전처리 조건을 분석하고자 한다. 산농도, 전처리 시간, 반응 온도를 조절하여 2(3) factorial central composite experimental design을 바탕으로 각기 다른 l5가지의 전처리 조건에서 시험하였다(central point에서 2반복). 전처리 후 고체 시료는 발효 균주인 Pichia stipitis를 사용하여 동시 당화발효로 에탄올 생산에 이용되었으며, 각각의 시료에서의 72시간에서의 에탄올 생산량(y,g/l)이 최대값으로, 종속변수로써 RSM에 적용되었다. 180℃에서 40분간 0.013 g/ g의 옥살산으로 처리한 시료가 가장 많은 양의 에탄올(9.7 g/l)을 생산하였으며, response surface methodology 분석에 따르면, 전처리 조건에서 온도 인자가 ethanol에 가장 큰 영향을 미치는 것으로 제시되었으며, 결과는 수식화되어 나타내었다.

  • Organosolv pretreatment of Liriodendron tulipifera and simultaneous saccharification and fermentation for bioethanol production
    Biomass and Bioenergy, 2011
    Co-Authors: Bon-wook Koo, Ho-yong Kim, Nahyun Park, Soo-min Lee, Hwanmyeong Yeo, Ingyu Choi
    Abstract:

    An acid-free organosolv process was proposed to overcome the problems caused by acid catalyst in organosolv process, thereby producing ethanol from Liriodendron tulipifera effectively. Although relative lignin contents were above 20%, enzymatic conversion increased significantly to 65% at all conditions, and thus correlation between lignin and enzymatic conversion could not be explained using relative lignin content. Enzymatic conversion increased significantly above 65% regardless of temperature, which suggests the organosolv pretreatment with sodium hydroxide can be performed at lower temperature. FE-SEM showed that the process made the structure loose and broke down biomass through lignin dissolution. Wrinkle formation by alkaline swelling was also observed and it might increase surface area. Although pore-volume increased slightly, it was not the sole key factor for the organosolv pretreatment with sodium hydroxide. Increase in surface area and enzyme adsorption enhanced the enzymatic hydrolysis. Ethanol of 96% could be produced theoretically and it suggested that the acid-free organosolv process was an effective pretreatment method for bioethanol production from L. tulipifera.

Chung-yi Chen - One of the best experts on this subject based on the ideXlab platform.

  • antioxidant and anticancer constituents from the leaves of Liriodendron tulipifera
    Molecules, 2014
    Co-Authors: Yafei Kang, Chung-yi Chen
    Abstract:

    Sixteen compounds were extracted and purified from the leaves of Liriodendron tulipifera. These compounds include aporphines, oxoaporphine, coumarin, sesquiterpene lactone, benzenoids, cyclitol and steroids. (+)-Norstephalagine (2) (an aporphine) and scopoletin (8) (a coumarin) were isolated from Liriodendron tulipifera leaves from the first time. The identified compounds were screened for their antiradical scavenging, metal chelating and ferric reducing power activities. The results have showed that these compounds have antioxidative activity. The study has also examined the chemopreventive property of the isolated compounds against human melanoma cells A375. The results shown that (−)-anonaine (1), (−)-liridinine (3), (+)-lirinidine (6), lysicamine (7) and epitulipinolide diepoxide (9) significantly inhibited the proliferation of melanoma cells. These results revealed that these compounds have antioxidative activity and chemopreventive activity in skin melanoma cells.

  • Biofunctional Constituents from Liriodendron tulipifera with Antioxidants and Anti-Melanogenic Properties
    International journal of molecular sciences, 2013
    Co-Authors: Yi-chieh Lin, Chung-yi Chen, Zhi-hong Wen, Po-len Liu, Hui-min Wang
    Abstract:

    From the stems of Liriodendron tulipifera, seventeen known compounds have been extracted, isolated and purified. By using spectroscopic analysis, the structures of these pure constituents were determined as three lignans, four steroids and ten benzenoids. Identified compounds were screened for antioxidant abilities using: 1,1-diphenyl-2-picrylhydrazul (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging free radical activity assays; metal chelating power test; and ferric reducing/antioxidant power (FRAP) examination. The result revealed that seventeen compounds had potential anti-oxidative capabilities. In addition, the anti-tyrosinase effect was determined by calculating the hydroxylation of L-tyrosine to L-dopa and the oxidization of L-dopa to dopaquinone, according to in vitro mushroom tyrosinase evaluation platform. Furthermore, based on assays on B16F10 cell line, our data suggest that five compounds isolated from L. tulipifera would be able to inhibit tyrosinase activity and reduce the melanin content in animal cells. Therefore, some of the examined compounds could be potentially used in the cosmetic skin whitening business, therapeutic applications or the food industry.

  • Bio-Functional Constituents from the Stems of Liriodendron tulipifera
    Molecules, 2012
    Co-Authors: Chien-chih Chiu, Han-lin Chou, Pei-fang Wu, Hui-min Wang, Hsin Liang Chen, Chung-yi Chen
    Abstract:

    Four known compounds have been isolated from the stems of Liriodendron tulipifera, and the structures of these pure constituents were determined using spectroscopic analysis. Isolated compounds were screened for free radical scavenging ability, metal chelating power assay and ferric reducing antioxidant power assay (FRAP). The anti-tyrosinase effects of L. tulipifera compounds were calculated the inhibition of hydroxylation of L-tyrosine to L-dopa according to an in vitro mushroom tyrosinase assay. The study also examined the bio-effects of the four compounds on the human melanoma A375.S2, and showed that liriodenine (1) and (-)-norglaucine (4) significantly inhibited the proliferation of melanoma cells in the cell viability assay. Wound healing results indicated that liriodenine (1), (-)-glaucine (3) and (-)-norglaucine (4) exerted anti-migration potential. Interestingly, (-)-glaucine (3), neither liriodenine (1) nor (-)-norglaucine (4) showed promising anti-migration potential without inducing significant cytotoxicity. Furthermore, a dramatically increased level of intracellular reactive oxygen species (ROS) was detected from (-)-glaucine (3). The cell cycle assessment demonstrated a moderate G2/M accumulation by (-)-glaucine (3). The above results revealed the anti-cancer effects of L. tulipifera compounds, especially on the anti-migration ability indicating the promising chemopreventive agents to human skin melanoma cells.

Takashi Okuyama - One of the best experts on this subject based on the ideXlab platform.

  • tensile growth stress and lignin distribution in the cell walls of yellow poplar Liriodendron tulipifera linn
    Trees-structure and Function, 2002
    Co-Authors: Masato Yoshida, Haruki Ohta, Hiroyuki Yamamoto, Takashi Okuyama
    Abstract:

    Five specimens that contained a continuous gradient of wood, from normal to tension wood regions, were collected from an inclined yellow poplar (Liriodendron tulipifera), and the released strain of tensile growth stress was quantified. Ultraviolet (UV) microspectrophotometry was used to examine the relationship between lignin distribution in the cell wall and the intensity of tensile growth stress. The UV absorption of the secondary wall and the cell corner middle lamella decreased with increasing tensile released strain (i.e., tensile growth stress). The UV absorption in the compound middle lamella region remained virtually constant, irrespective of the tensile released strain. The absorption maximum (λmax) remained virtually constant in the secondary wall, the cell corner middle lamella, and the compound middle lamella region at 273–274, 277–278, and 275–278 nm respectively, irrespective of the tensile released strain. The ratios of the UV absorbance at 280 to 260 nm and 280 to 273 nm of the secondary wall decreased with increasing tensile released strain. The ratios in the cell corner and compound middle lamella region remained constant, irrespective of the tensile released strain. The lignin content of the secondary wall decreased, while the syringyl/guaiacyl ratio increased with increasing tensile released strain. Gelatinous fibers were not observed in the tension wood regions, but the secondary wall became gelatinous-layer-like, i.e., the lignin content and microfibrillar angle decreased and the cellulose content increased. A definite gelatinous layer seems to be important for generating greater tensile growth stress. It is concluded that a decrease in lignin and an increase in cellulose microfibrils parallel to the fiber axis in the secondary wall are necessary to produce large tensile growth stress.

  • tension wood and growth stress induced by artificial inclination in Liriodendron tulipifera linn and prunus spachiana kitamura f ascendens kitamura
    Annals of Forest Science, 2000
    Co-Authors: Masato Yoshida, Tomonobu Okuda, Takashi Okuyama
    Abstract:

    La relation entre la contrainte de croissance et le niveau d'inclinaison artificielle a ete etudiee sur des pousses de deux especes angiospermes. La contrainte de croissance de traction generee par Prunus spachiana, qui produit des fibres gelatineuses, est plus forte que celle de Liriodendron tulipifera, qui n'en produit pas. Dans les deux especes, une augmentation de l'inclinaison de 0 a 20° par rapport a la verticale, produit proportionnellement une augmentation de la contrainte de traction generee sur la face superieure de la tige inclinee et une decroissance de l'angle des microfibrilles cellulosiques. Des inclinaisons superieures a 20° ne produisent pas de variation supplementaire, ni de la contrainte ni de l'angle des microfibrilles. La largeur du cerne en cours de formation augmente lineairement avec l'angle d'inclinaison, toutefois l'excentricite de la croissance n'est pas un facteur contribuant de maniere dominante au moment de flexion induisant le retour a la position verticale normale. Cet article revele le caractere borne de la contrainte de croissance, qui peut augmenter jusqu'a un certain point mais ensuite ne depasse pas cette limite.

  • Tension wood and growth stress induced by artificial inclination in Liriodendron tulipifera Linn. and Prunus spachiana Kitamura f. ascendens Kitamura
    Annals of Forest Science, 2000
    Co-Authors: Masato Yoshida, Tomonobu Okuda, Takashi Okuyama
    Abstract:

    International audienceThe relationship between the amount of growth stress and the degree of artificial inclination was investigated in saplings of two angiosperm species. The tensile growth stresses generated in Prunus spachiana, which forms gelatinous fibers, were larger than those in Liriodendron tulipifera, which does not form gelatinous fibers. In both species, the tensile growth stresses generated in the upper side of inclined stems increased and the cellulose microfibrillar angle decreased proportionally as the inclination changed from 0° (vertical) to 20°. At inclinations over 20°, the tensile growth stress and cellulose microfibrillar angle did not change further. The thickness of the current growth layer increased linearly with the angle of inclination, but eccentric growth was not the main factor contributing to the upward bending moment to return the axis to the normal vertical position. This paper reveals that the growth stress generated by inclination is limited. That is, growth stress increases with the inclination angle to a point, but then does not increase further.Bois de tension et contrainte de croissance induits par inclinaison artificielle chez Liriodendron tulipifera Linn. et Prunus spachiana Kitamura f. ascendens Kitamura. La relation entre la contrainte de croissance et le niveau d'inclinaison artificielle a été étudiée sur des pousses de deux espèces angiospermes. La contrainte de croissance de traction générée par Prunus spachiana, qui produit des fibres gélatineuses, est plus forte que celle de Liriodendron tulipifera, qui n'en produit pas. Dans les deux espèces, une augmentation de l'inclinaison de 0 à 20° par rapport à la verticale, produit proportionnellement une augmentation de la contrainte de traction générée sur la face supérieure de la tige inclinée et une décroissance de l'angle des microfibrilles cellulosiques. Des inclinaisons supérieures à 20° ne produisent pas de variation supplémentaire, ni de la contrainte ni de l'angle des microfibrilles. La largeur du cerne en cours de formation augmente linéairement avec l'angle d'inclinaison, toutefois l'excentricité de la croissance n'est pas un facteur contribuant de manière dominante au moment de flexion induisant le retour à la position verticale normale. Cet article révèle le caractère borné de la contrainte de croissance, qui peut augmenter jusqu'à un certain point mais ensuite ne dépasse pas cette limite

Robert O. Teskey - One of the best experts on this subject based on the ideXlab platform.

  • Effects of stem size on stem respiration and its flux components in yellow-poplar (Liriodendron tulipifera L.) trees.
    Tree physiology, 2017
    Co-Authors: Hailan Fan, Mary Anne Mcguire, Robert O. Teskey
    Abstract:

    Carbon dioxide (CO2) released from respiring cells in the stems of trees (RS) can diffuse radially to the atmosphere (EA) or dissolve in xylem sap and move internally in the tree (FT). Previous studies have observed that EA decreases as stem or branch diameter increases, but the cause of this relationship has not been determined, nor has the relationship been confirmed between stem diameter and RS, which includes both EA and FT. In this study, for the first time the mass balance technique was used to estimate RS of stems of Liriodendron tulipifera L. trees of different diameters, ranging from 16 to 60 cm, growing on the same site. The magnitude of the component fluxes scaled with tree size. Among the five trees, the contribution of EA to RS decreased linearly with increasing stem diameter and sapwood area while the contribution of FT to RS increased linearly with stem diameter and sapwood area. For the smallest tree EA was 86% of RS but it was only 46% of RS in the largest tree. As tree size increased a greater proportion of respired CO2 dissolved in sap and remained within the tree. Due to increase in FT with tree size, we observed that trees of different sizes had the same RS even though they had different EA. This appears to explain why the EA of stems and branches decreases as their size increases.

Masato Yoshida - One of the best experts on this subject based on the ideXlab platform.

  • tensile growth stress and lignin distribution in the cell walls of yellow poplar Liriodendron tulipifera linn
    Trees-structure and Function, 2002
    Co-Authors: Masato Yoshida, Haruki Ohta, Hiroyuki Yamamoto, Takashi Okuyama
    Abstract:

    Five specimens that contained a continuous gradient of wood, from normal to tension wood regions, were collected from an inclined yellow poplar (Liriodendron tulipifera), and the released strain of tensile growth stress was quantified. Ultraviolet (UV) microspectrophotometry was used to examine the relationship between lignin distribution in the cell wall and the intensity of tensile growth stress. The UV absorption of the secondary wall and the cell corner middle lamella decreased with increasing tensile released strain (i.e., tensile growth stress). The UV absorption in the compound middle lamella region remained virtually constant, irrespective of the tensile released strain. The absorption maximum (λmax) remained virtually constant in the secondary wall, the cell corner middle lamella, and the compound middle lamella region at 273–274, 277–278, and 275–278 nm respectively, irrespective of the tensile released strain. The ratios of the UV absorbance at 280 to 260 nm and 280 to 273 nm of the secondary wall decreased with increasing tensile released strain. The ratios in the cell corner and compound middle lamella region remained constant, irrespective of the tensile released strain. The lignin content of the secondary wall decreased, while the syringyl/guaiacyl ratio increased with increasing tensile released strain. Gelatinous fibers were not observed in the tension wood regions, but the secondary wall became gelatinous-layer-like, i.e., the lignin content and microfibrillar angle decreased and the cellulose content increased. A definite gelatinous layer seems to be important for generating greater tensile growth stress. It is concluded that a decrease in lignin and an increase in cellulose microfibrils parallel to the fiber axis in the secondary wall are necessary to produce large tensile growth stress.

  • tension wood and growth stress induced by artificial inclination in Liriodendron tulipifera linn and prunus spachiana kitamura f ascendens kitamura
    Annals of Forest Science, 2000
    Co-Authors: Masato Yoshida, Tomonobu Okuda, Takashi Okuyama
    Abstract:

    La relation entre la contrainte de croissance et le niveau d'inclinaison artificielle a ete etudiee sur des pousses de deux especes angiospermes. La contrainte de croissance de traction generee par Prunus spachiana, qui produit des fibres gelatineuses, est plus forte que celle de Liriodendron tulipifera, qui n'en produit pas. Dans les deux especes, une augmentation de l'inclinaison de 0 a 20° par rapport a la verticale, produit proportionnellement une augmentation de la contrainte de traction generee sur la face superieure de la tige inclinee et une decroissance de l'angle des microfibrilles cellulosiques. Des inclinaisons superieures a 20° ne produisent pas de variation supplementaire, ni de la contrainte ni de l'angle des microfibrilles. La largeur du cerne en cours de formation augmente lineairement avec l'angle d'inclinaison, toutefois l'excentricite de la croissance n'est pas un facteur contribuant de maniere dominante au moment de flexion induisant le retour a la position verticale normale. Cet article revele le caractere borne de la contrainte de croissance, qui peut augmenter jusqu'a un certain point mais ensuite ne depasse pas cette limite.

  • Tension wood and growth stress induced by artificial inclination in Liriodendron tulipifera Linn. and Prunus spachiana Kitamura f. ascendens Kitamura
    Annals of Forest Science, 2000
    Co-Authors: Masato Yoshida, Tomonobu Okuda, Takashi Okuyama
    Abstract:

    International audienceThe relationship between the amount of growth stress and the degree of artificial inclination was investigated in saplings of two angiosperm species. The tensile growth stresses generated in Prunus spachiana, which forms gelatinous fibers, were larger than those in Liriodendron tulipifera, which does not form gelatinous fibers. In both species, the tensile growth stresses generated in the upper side of inclined stems increased and the cellulose microfibrillar angle decreased proportionally as the inclination changed from 0° (vertical) to 20°. At inclinations over 20°, the tensile growth stress and cellulose microfibrillar angle did not change further. The thickness of the current growth layer increased linearly with the angle of inclination, but eccentric growth was not the main factor contributing to the upward bending moment to return the axis to the normal vertical position. This paper reveals that the growth stress generated by inclination is limited. That is, growth stress increases with the inclination angle to a point, but then does not increase further.Bois de tension et contrainte de croissance induits par inclinaison artificielle chez Liriodendron tulipifera Linn. et Prunus spachiana Kitamura f. ascendens Kitamura. La relation entre la contrainte de croissance et le niveau d'inclinaison artificielle a été étudiée sur des pousses de deux espèces angiospermes. La contrainte de croissance de traction générée par Prunus spachiana, qui produit des fibres gélatineuses, est plus forte que celle de Liriodendron tulipifera, qui n'en produit pas. Dans les deux espèces, une augmentation de l'inclinaison de 0 à 20° par rapport à la verticale, produit proportionnellement une augmentation de la contrainte de traction générée sur la face supérieure de la tige inclinée et une décroissance de l'angle des microfibrilles cellulosiques. Des inclinaisons supérieures à 20° ne produisent pas de variation supplémentaire, ni de la contrainte ni de l'angle des microfibrilles. La largeur du cerne en cours de formation augmente linéairement avec l'angle d'inclinaison, toutefois l'excentricité de la croissance n'est pas un facteur contribuant de manière dominante au moment de flexion induisant le retour à la position verticale normale. Cet article révèle le caractère borné de la contrainte de croissance, qui peut augmenter jusqu'à un certain point mais ensuite ne dépasse pas cette limite