Antimicrobial Constituents from Fruits of Ailanthus Altissima SWINGLE

Zhao Chun-Chao,Shao Jian-Hua,Li Xian,Xu Jing,Zhang Peng The Pharmaceutical Society of Korea 2005 Archives of Pharmacal Research Vol.28 No.10

A new naturally occurring sterol, compound 5, and six known stigmasterols were isolated from fruits of Ailanthus altissima Swingle by repeated column chromatography and RP-HPLC. Their structures were identified as, 5${\alpha}$-stigmastane-3,6-dione (1), 3${\beta}$-hydroxystigmast-5-en-7-one (2), stigmast-5-ene-3${\beta}$, 7${\alpha}$-diol (3), 6${\alpha}$-hydroxystigmast-4-en-3-one (4), 5${\alpha}$-stigmastane-3${\beta}$, 6${\beta}$-diol (5), stigmast-4-ene-3${\beta}$, 6${\alpha}$-diol (6), stigmast-5-ene-3${\beta}$, 7${\alpha}$, 20$\xi$-triol (7) by spectral analysis and comparison with the published data. These compounds have not been reported from genus Ailanthus, whereas compound 7 was identified by NMR for the first time. In addition, the $95\%$ ethanol extract and compounds from the fruits of Ailanthus altissima SWINGLE were assayed for in vitro antimicrobial activity. The extract was potent active against the assayed bacteria while compounds 3 and 7 exhibited moderate activity.

Antimicrobial Constituents from Fruits of Ailanthus Altissima SWINGLE

Chun-Chao Zhao,Jian-Hua Shao,Xian Li,Jing Xu,Peng Zhang 대한약학회 2005 Archives of Pharmacal Research Vol.28 No.10

A new naturally occurring sterol, compound 5, and six known stigmasterols were isolated from fruits of Ailanthus altissima Swingle by repeated column chromatography and RP-HPLC. Their structures were identified as, 5α-stigmastane-3,6-dione (1), 3β-hydroxystigmast-5-en-7-one (2), stigmast-5-ene-3β, 7α-diol (3), 6α-hydroxystigmast-4-en-3-one (4), 5α-stigmastane-3β, 6β- diol (5), stigmast-4-ene-3β, 6α-diol (6), stigmast-5-ene-3β, 7α, 20ξ-triol (7) by spectral analysis and comparison with the published data. These compounds have not been reported from genus Ailanthus, whereas compound 7 was identified by NMR for the first time. In addition, the 95% ethanol extract and compounds from the fruits of Ailanthus altissima SWINGLE were assayed for in vitro antimicrobial activity. The extract was potent active against the assayed bacteria while compounds 3 and 7 exhibited moderate activity.

Recombinant Human Granulocyte Colony-Stimulating Factor Promotes Preinvasive and Invasive Estrogen Receptor-Positive Tumor Development in MMTV-erbB2 Mice

Chun Ling Zhao,Guang Ping Zhang,Zheng Zheng Xiao,Zhi Kun Ma,Cai Peng Lei,Shi Yuan Song,Ying Ying Feng,Ya Chao Zhao,Xiao Shan Feng 한국유방암학회 2015 Journal of breast cancer Vol.18 No.2

Purpose: We investigated whether recombinant human granulocyte colony-stimulating factor (rhG-CSF) could promote the development of preinvasive and invasive breast cancer in mouse mammary tumor virus (MMTV-erbB2) mice with estrogen receptor- positive tumors. Methods: MMTV-erbB2 mice were randomly divided into three experimental groups with 20 mice in each group. MMTV-erbB2 mice were treated with daily subcutaneous injections of vehicle or rhG-CSF (low-rhG-CSF group, rhG-CSF 0.125 μg; vehicle-rhG-CSF group, normal saline 0.25 μg; and high-rhG-CSF group, rhG-CSF 0.25 μg) at 3 months of age. Cellular and molecular mechanisms of G-CSF action in mammary glands were investigated via immunohistochemistry and reverse transcription polymerase chain reaction. Results: Low, but not high, rhG-CSF doses significantly accelerated mammary tumorigenesis in MMTV-erbB2 mice. Short-term treatment with rhG-CSF could significantly promote the development of preinvasive mammary lesions. The cancer prevention effect was associated with reduced expression of proliferating cell nuclear antigen, cluster of differentiation 34, and signal transducers and activators of transcription 3 in mammary glands by >80%. Conclusion: We found that G-CSF was regulated by rhG-CSF both in vitro and in vivo. Identification of G-CSF genes helped us further understand the mechanism by which G-CSF promotes cancer. Low doses of rhG-CSF could significantly increase tumor latency and increase tumor multiplicity and burden. Moreover, rhG-CSF effectively promotes development of both malignant and premalignant mammary lesions in MMTV-erbB2 mice.

Antifungal activity of Streptomyces albidoflavus L131 against the leaf mold pathogen Passalora fulva involves membrane leakage and oxidative damage

Chao Chen,Yumei Wang,Chun Su,Xinqing Zhao,Ming Li,Xiaowei Meng,김영우,양승환,Yushu Ma,Dong-Zhi Wei,서주원 한국응용생명화학회 2015 Applied Biological Chemistry (Appl Biol Chem) Vol.58 No.1

Passalora fulva (or Fulvia fulva) is the causalmicroorganism of tomato leaf mold, the outbreak of whichoccurs worldwide in greenhouse especially when humidityis high. However, studies on antifungal agents of P. fulvaare still very limited. In this study, a marine-derivedStreptomyces albidoflavus strain L131 showing potentinhibitory activities against P. fulva was identified andcharacterized. The active antifungal components wereobtained, and studies on the antifungal mechanisms of thecrude extract showed that the antifungal metabolites ofL131 caused damage of hyphae and spore development, aswell as plasma membrane of P. fulva. In addition, accumulationof endogenous reactive oxygen species of the leafpathogen was also observed after treatment by cultureextracts of L131. To our knowledge, this is the first reporton the studies of the antifungal mechanisms againstP. fulva, which benefit further development of biocontrolagent against tomato leaf mold disease.

Experimental Study and Analysis of Insulator Breakdown Characteristics with Short-tail Lightning Impulse

Zhao, Yuan,Li, Yu,Deng, Chun,Yuan, Yi-Chao,He, Jin-Liang,Wang, Xi The Korean Institute of Electrical Engineers 2014 The Journal of International Council on Electrical Vol.4 No.3

The voltage waveform on the insulator by a direct lightning stroke is a short-tail lightning impulse. Experimental study and analysis of insulator breakdown characteristics under short-tail lightning impulses are given in this paper with the contrast of standard lightning impulse. The impacts of crossarm and transmission lines are also considered. The experimental results indicate that the insulator 50% breakdown voltage under short-tail impulse is significantly higher than that of standard wave with both positive and negative polarities, about 25~30%. The 50% breakdown voltage of insulator with negative-polarity short-tail impulse is about 5% higher than with positive-polarity one. The insulator voltage-time characteristics are also given with short-tail and standard lightning impulses.

Antifungal activity of Streptomyces albidoflavus L131 against the leaf mold pathogen Passalora fulva involves membrane leakage and oxidative damage

Chen, Chao,Wang, Yumei,Su, Chun,Zhao, Xinqing,Li, Ming,Meng, Xiaowei,Jin, Yingyu,Yang, Seung-Hwan,Ma, Yushu,Wei, Wei,Joo-Won, Suh 한국응용생명화학회 2015 Applied Biological Chemistry (Appl Biol Chem) Vol.58 No.1

Passalora fulva (or Fulvia fulva) is the causal microorganism of tomato leaf mold, the outbreak of which occurs worldwide in greenhouse especially when humidity is high. However, studies on antifungal agents of P. fulva are still very limited. In this study, a marine-derived Streptomyces albidoflavus strain L131 showing potent inhibitory activities against P. fulva was identified and characterized. The active antifungal components were obtained, and studies on the antifungal mechanisms of the crude extract showed that the antifungal metabolites of L131 caused damage of hyphae and spore development, as well as plasma membrane of P. fulva. In addition, accumulation of endogenous reactive oxygen species of the leaf pathogen was also observed after treatment by culture extracts of L131. To our knowledge, this is the first report on the studies of the antifungal mechanisms against P. fulva, which benefit further development of biocontrol agent against tomato leaf mold disease.

A New Ferulic Acid Ester and Other Constituents from Dracocephalum peregrinum

Li-Min Dai,Chun-Chao Zhao,Hui-zi Jin,Yun-Heng Shen,Hui-Liang Li,Cai-Yun Peng,Jian Tang,Wei-Dong Zhang 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.10

A new ferulic acid ester, 1'-methyl-2'-hydroxyethyl ferulate (1), together with methylcaffeate (2), 4- hydroxy cinnamic acid (3), ferulic acid (4), caffeic acid (5), diosmetin (6), luteolin (7), 5,3',4'-trihydroxy- 3,7-dimethoxyflavone (8), eriodictyol (9), kaempferol (10), quercetin (11), acacetin-7-Oglcopyranoside (12), 4-(β-glucopyranosyloxy) benzoic acid (13), luteolin-7-O-(6''-feruloyl) glucopyranoside (14), luteolin-7-O-glucopyranoside (15), kaempferide-3-O-rhamnopyranoside (16), quercitrin (17), kaempferol-3-O-glucopyranoside (18), prunasin (19), quercetin-7-O-glucopyranoside (20), quercetin-3-O-glucopyranoside (21), plantaginin (22), linarin (23), luteolin-7-O-rutinoside (24), and chlorogenic acid (25) were isolated from the aerial parts of Dacocephalum peregrinum. The structure of 1 was elucidated on the basis of spectroscopic and HR-ESI-MS analyses. In addition, compound 1 exhibited mild inhibitory effect on NO production in LPS-stimulated RAW264.7 cells.

A New Ferulic Acid Ester and Other Constituents from Dracocephalum peregrinum

Dai, Li-Min,Zhao, Chun-Chao,Jin, Hui-Zi,Tang, Jian,Shen, Yun-Heng,Li, Hui-Liang,Peng, Cai-Yon,Zhang, Wei-Dong 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.10

A new ferulic acid ester, 1'-methyl-2'-hydroxyethyl ferulate (1), together with methylcaffeate (2), 4-hydroxy cinnamic acid (3), ferulic acid (4), caffeic acid (5), diosmetin (6), luteolin (7), 5,3',4'-trihydroxy-3,7-dimethoxyflavone (8), eriodictyol (9), kaempferol (10), quercetin (11), acacetin-7-O-glcopyranoside (12), 4-($\beta$-glucopyranosyloxy) benzoic acid (13), luteolin-7-O-(6"-feruloyl) glucopyranoside (14), luteolin-7-O-glucopyranoside (15), kaempferide-3-O-rhamnopyranoside (16), quercitrin (17), kaempferol-3-O-glucopyranoside (18), prunasin (19), quercetin-7-O-glucopyranoside (20), quercetin-3-O-glucopyranoside (21), plantaginin (22), linarin (23), luteolin-7-O-rutinoside (24), and chlorogenic acid (25) were isolated from the aerial parts of Dacocephalum peregrinum. The structure of 1 was elucidated on the basis of spectroscopic and HR-ESI-MS analyses. In addition, compound 1 exhibited mild inhibitory effect on NO production in LPS-stimulated RAW264.7 cells.

Impact of Elevational Gradients and Chemical Parameters on Changes in Soil Bacterial Diversity Under Semiarid Mountain Region

Khan Salman,Han Chun,Iqbal Awais,Guan Chao,Zhao Changming 한국미생물학회 2023 The journal of microbiology Vol.61 No.10

Elevation gradients, often regarded as “natural experiments or laboratories”, can be used to study changes in the distribution of microbial diversity related to changes in environmental conditions that typically occur over small geographical scales. We obtained bacterial sequences using MiSeq sequencing and clustered them into operational taxonomic units (OTUs). The total number of reads obtained by the bacterial 16S rRNA sequencing analysis was 1,090,555, with an average of approximately 45,439 reads per sample collected from various elevations. The current study observed inconsistent bacterial diversity patterns in samples from the lowest to highest elevations. 983 OTUs were found common among all the elevations. The most unique OTUs were found in the soil sample from elevation_2, followed by elevation_1. Soil sample collected at elevation_6 had the least unique OTUs. Actinobacteria, Protobacteria, Chloroflexi were found most abundant bacterial phyla in current study. Ammonium nitrogen ( NH4 +-N), and total phosphate (TP) are the main factors influencing bacterial diversity at elevations_ 1. pH was the main factor influencing the bacterial diversity at elevations_2, elevation_3 and elevation_4. Our results provide new visions on forming and maintaining soil microbial diversity along an elevational gradient and have implications for microbial responses to environmental change in semiarid mountain ecosystems.

Boundary Layer and Cooling Rate and Microstructure Formation on the Cooling Sloping Plate

Ren Guo Guan,Zhan Yong Zhao,Run Ze Chao,Lei Dong,이종수,Chun Ming Liu 대한금속·재료학회 2013 METALS AND MATERIALS International Vol.19 No.5

During melt treatment by cooling sloping plate, laminar flow and turbulent flow exist on sloping plate surface commonly. The thickness of velocity boundary layer and the critical transfer distance from laminar flow to turbulent flow increase with the decrease of initial flow velocity. The thickness of temperature boundary layer increases with the increment of flow distance and the decrease of initial flow velocity. The melt cooling rate and melt thickness have an inverse proportion relationship. The melt cooling rate of cooling sloping plate process can reach 102-103 K/s and belongs to meta-rapid solidification scope. Uniform solute field and high cooling rate can lead to eruptive nucleation. In addition, a large quantity of heterogonous nuclei appears on the sloping plate surface, and vibrating flow can enable heterogonous nucleus to escape off the plate, which leads to nucleus multiplication. Under relative uniform solute field and high cooling rate, some grains can keep stable growth surface, go on growing with the round surface and finally maintain their globular structure. However, there are always some grains that grow along a certain preferred direction, but under vibrating flow their dendritic arms break and transform into near spherical structure.