Obovatol isolated from <i>Magnolia obovata</i> enhances pentobarbital-induced sleeping time: Possible involvement of GABA_A receptors/chloride channel activation

Ma, Hong,Jo, Young-Jun,Ma, Yuan,Hong, Jin-Tae,Kwon, Byoung-Mog,Oh, Ki-Wan Elsevier 2009 Phytomedicine Vol.16 No.4

<P><B>Abstract</B></P><P>This study aimed to investigate the effects of obovatol isolated from <I>Magnolia obovata</I> on pentobarbital-induced sleeping behaviors and to determine whether these effects were mediated by GABA<SUB>A</SUB> receptors/chloride channel activation, using a western blot technique and Cl<SUP>−</SUP> sensitive fluorescence probe. GABA<SUB>A</SUB> receptors subunits expression and chloride influx were investigated in cultured cerebellar granule cells. Obovatol (0.05, 0.1, and 0.2mg/kg) prolonged the sleeping time induced by pentobarbital (42mg/kg). In addition, obovatol (20 and 50μM) significantly increased Cl<SUP>−</SUP> influx in the primary cultured cerebellar granule cells. Moreover, obovatol increased the expression of GABA<SUB>A</SUB> receptor α-, β-, and γ-subunits. However, it had no effect on the abundance of the expression of glutamic acid decarboxylase (GAD), suggesting that obovatol might not activate GAD. These results suggest that obovatol potentiates pentobarbital-induced sleeping time through the GABA<SUB>A</SUB> receptors/chloride channel activation.</P>

Interface Engineering for Organic Electronics

Ma, Hong,Yip, Hin-Lap,Huang, Fei,Jen, Alex K.-Y. WILEY-VCH Verlag 2010 Advanced Functional Materials Vol.20 No.9

<P>The field of organic electronics has been developed vastly in the past two decades due to its promise for low cost, lightweight, mechanical flexibility, versatility of chemical design and synthesis, and ease of processing. The performance and lifetime of these devices, such as organic light-emitting diodes (OLEDs), photovoltaics (OPVs), and field-effect transistors (OFETs), are critically dependent on the properties of both active materials and their interfaces. Interfacial properties can be controlled ranging from simple wettability or adhesion between different materials to direct modifications of the electronic structure of the materials. In this Feature Article, the strategies of utilizing surfactant-modified cathodes, hole-transporting buffer layers, and self-assembled monolayer (SAM)-modified anodes are highlighted. In addition to enabling the production of high-efficiency OLEDs, control of interfaces in both conventional and inverted polymer solar cells is shown to enhance their efficiency and stability; and the tailoring of source–drain electrode–semiconductor interfaces, dielectric–semiconductor interfaces, and ultrathin dielectrics is shown to allow for high-performance OFETs.</P> <B>Graphic Abstract</B> <P>The strategies of utilizing surfactant-modified cathodes, hole-transporting buffer layers, and self-assembled-monolayer (SAM)-modified anodes for high-efficiency organic light-emitting diodes (OLEDs) are highlighted. Controlling the interfaces of conventional and inverted polymer solar cells (PSCs) are also shown to enhance efficiency and stability, while tailoring source–drain electrode–semiconductor interfaces, dielectric–semiconductor interfaces, and ultrathin dielectrics allow for high-performance organic field-effect transistors (OFETs). <img src='wiley_img_2010/1616301X-2010-20-9-ADFM200902236-content.gif' alt='wiley_img_2010/1616301X-2010-20-9-ADFM200902236-content'> </P>

Magnolol enhances pentobarbital-induced sleeping behaviors: possible involvement of GABAergic systems

Ma, Hong,Kim, Chung-Soo,Ma, Yuan,Nam, Sang-Yoon,Kim, Dong-Seon,Woo, Sung-Sick,Hong, Jin-Tae,Oh, Ki-Wan John Wiley Sons, Ltd. 2009 Phytotherapy research Vol.23 No.9

<P>This study was performed to investigate whether magnolol enhances pentobarbital-induced sleeping behaviors through the GABAergic systems. Magnolol prolonged the sleeping time induced by pentobarbital. In addition, magnolol increased chloride influx in primary cultured cerebellar granule cells. The expression of the GABA<SUB>A</SUB> receptor &agr;-subunit was increased selectively by magnolol, but magnolol had no effect on the abundance of &bgr;- or &ggr;-subunits. The expression of glutamic acid decarboxylase (GAD) was not influenced by magnolol. It is suggested that magnolol may enhance pentobarbital-induced sleeping behaviors through the activation of GABAergic systems. Copyright © 2009 John Wiley & Sons, Ltd.</P>

Demonstration of monolignol β-glucosidase activity of rice Os4BGlu14, Os4BGlu16 and Os4BGlu18 in <i>Arabidopsis thaliana bglu</i>45 mutant

Baiya, Supaporn,Mahong, Bancha,Lee, Sang-Kyu,Jeon, Jong-Seong,Ketudat Cairns, James R. Elsevier 2018 Vol. No.

<P><B>Abstract</B></P> <P>The glycoside hydrolase family 1 members Os4BGlu14, Os4BGlu16, and Os4BGlu18 were proposed to be rice monolignol β-glucosidases. <I>In vitro</I> studies demonstrated that the Os4BGlu16 and Os4BGlu18 hydrolyze the monolignol glucosides coniferin and syringin with high efficiency compared to other substrates. The replacement of the conserved catalytic acid/base glutamate residue by a nonionizable glutamine residue in Os4BGlu14 suggested that it may be inactive as a β-glucosidase. Here, we investigated the activities of Os4BGlu14, Os4BGlu16, and Os4BGlu18 <I>in planta</I> by recombinant expression of their genes in the <I>Arabidopsis bglu</I>45-2 (monolignol β-glucosidase) mutant and analysis of monolignol glucosides by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MSMS). The <I>bglu</I>45-2 line exhibits elevated monolignol glucoside levels, but lower amounts of coniferin, syringin, and <I>p</I>-coumaryl alcohol glucoside were seen in <I>Arabidopsis bglu</I>45-2 rescued lines complemented by the <I>Os4BGlu14</I>, <I>Os4BGlu16</I>, and <I>Os4BGlu18</I> genes. These data suggest that the <I>bglu45-2</I> mutant has a broader effect on monolignols than previously reported and that the Os4BGlu14, Os4BGlu16 and Os4BGlu18 proteins act as monolignol β-glucosidases to complement the defect. An OsBGlu16-GFP fusion protein localized to the cell wall. This apoplastic localization and the effect of these enzymes on monolignol glucoside levels suggest monolignol glucosides from the vacuole may meet the monolignol β-glucosidases, despite their different localization.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Triple quadrapole LCMSMS was used to monitor monolignols in Arabidopsis. </LI> <LI> Arabidopsis <I>bglu</I>45-2 has higher levels of monolignol glucosides than wild type. </LI> <LI> Overexpression of Os4BGlu14, 16, and 18 in this line decreased monolignol glucosides. </LI> <LI> Os4BGlu14 complemented the <I>bglu</I>45-2 mutation, despite lacking a catalytic acid/base. </LI> <LI> Os4BGlu16-eGFP was localized to the apoplast, apart from vacuolar glycosides. </LI> </UL> </P>

β-Glucosidases: Multitasking, moonlighting or simply misunderstood?

Ketudat Cairns, J.R.,Mahong, B.,Baiya, S.,Jeon, J.S. Elsevier Scientific Publishers Ireland Ltd 2015 Plant science Vol.241 No.-

β-Glucosidases have a wide range of functions in plants, including roles in recycling of cell-wall oligosaccharides, defense, phytohormone signaling, secondary metabolism, and scent release, among others. It is not always clear which one is responsible for a specific function, as plants contain a large set of β-glucosidases. However, progress has been made in recent years in elucidating these functions. To help understand what is known and what remains ambiguous, we review the general approaches to investigating plant β-glucosidase functions. We consider information that has been gained regarding glycoside hydrolase family 1 enzyme functions utilizing these approaches in the past decade. In several cases, one enzyme has been assigned different biological functions by different research groups. We suggest that, at least in some cases, the ambiguity of an enzyme's function may come from having multiple functions that may help coordinate the response to injury or other stresses.

Institutional and Natural Resource Use Dynamics and their Implications on Sustainable Watershed Management in the East Uluguru Mountains in Tanzania

Mattee, A.Z,Mahonge, C.P.I,Nsenga, J.V,Nindi, S.,H. Kayeye 한국외국어대학교(글로벌캠퍼스) 아프리카연구소 2010 Asian Journal of African Studies Vol.28 No.-

The mountainous areas are made of multiple and diverse natural resources with multiple uses as well as intricate interactions of socio‐economic and ecological interests. These interests are constructed on and governed by institutions. Both the resource use patterns and institutions are dynamic spatially and temporally and these changes determine sustainability of natural resource systems. This research used a methodology combing quantitative and qualitative techniques to study institutional and resource use pattern shifts in Mvuha watershed situated in the East Uluguru Mountains and implications of these shifts on sustainable management of the watershed. The analysis shows that institutional and resource use patterns have changed simultaneously but with some spatial and temporal congruencies and tensions. While the main institutional shifts occurred from traditional management regime through formal state‐centred management regime to the current collaborative institutional framework, the resource use shift was translated in changes in vegetation cover mainly due to the following anthropogenic factors. However, at some temporal points, changes in the institutions could not result in anticipated changes in resource use patterns. The analysis has further uncovered that the failure of centralised governmental efforts to effectuate sustainable natural resources management has led to the re‐accommodation of local institutions in the management regimes. However, local institutions should not be viewed monolithically and simplistically because within the local field exist diverse local institutions wherein some support sustainable natural resources management while others constrain this virtue. It is concluded that, first, thorough understanding of the informal institutional framework is imperative before formal institutional arrangements are proposed. Second, sustainable natural resource management cannot be attained until alternative livelihood strategies for the local people to meet their basic needs are considered and integrated.

Institutional and Natural Resource Use Dynamics and their Implications on Sustainable Watershed Management in the East Uluguru Mountains in Tanzania

Mattee, A.Z.,Mahonge, C.P.I.,Nsenga, J.V.,Nindi S.,H. Kayeye 한국외국어대학교 아프리카연구소 2010 Asian Journal of African Studies Vol.28 No.-

The mountainous areas are made of multiple and diverse natural resources with multiple uses as well as intricate interactions of socio-economic and ecological interests. These interests are constructed on and governed by institutions. Both the resource use patterns and institutions are dynamic spatially and temporally and these changes determine sustainability of natural resource systems. This research used a methodology combing quantitative and qualitative techniques to study institutional and resource use pattern shifts in Mvuha watershed situated in the East Uluguru Mountains and implications of these shifts on sustainable management of the watershed. The analysis shows that institutional and resource use patterns have changed simultaneously but with some spatial and temporal congruencies and tensions. While the main institutional shifts occurred from traditional management regime through formal state-centred management regime to the current collaborative institutional framework, the resource use shift was translated in changes in vegetation cover mainly due to the following anthropogenic factors. However, at some temporal points, changes in the institutions could not result in anticipated changes in resource use patterns. The analysis has further uncovered that the failure of centralised governmental efforts to effectuate sustainable natural resources management has led to the re-accommodation of local institutions in the management regimes. However, local institutions should not be viewed monolithically and simplistically because within the local field exist diverse local institutions wherein some support sustainable natural resources management while others constrain this virtue. It is concluded that, first, thorough understanding of the informal institutional framework is imperative before formal institutional arrangements are proposed. Second, sustainable natural resource management cannot be attained until alternative livelihood strategies for the local people to meet their basic needs are considered and integrated.

The Potential of Rural Farm Families in Resource Management in Tanzania

Nindi, S. J.,Mhando, D. G.,Mahonge, C. P. I.,Itani, J. 한국외국어대학교 아프리카연구소 2014 Asian Journal of African Studies Vol.35 No.-

Natural environment and socio-economic dimensions are interdependent because people get their basic needs from the environment, and inversely, for the integrity of the environment to be sustained, livelihood practices must become environmental friendly. Deterioration of environment and livelihoods interests in the Matengo highlands in Mbinga district triggered farmer-based initiatives through the facilitation of external based development partners. However, while farmers have organised themselves into groups in attempt to address the experienced livelihood-environment challenges since 2002, scant information exists on the role of farmers’ groups in that regard and hence this is the rationale for the present article. Using satellite data the article first substantiates the contention on deterioration of the natural environment by estimating the change in forest cover. Then, the role of farmers’ groups in improving the livelihood and conserving the environment is unveiled through focus group discussion, key informant interviews, informal interviews and observation methods. Consequently, recommendations are given as a way forward for improving the harmony between livelihood integrity and the sustainability of the natural environment.

The Potential of Rural Farm Families in Resource Management in Tanzania

Nindi, S. J.,Mhando, D. G.,Mahonge, C.P.I,Itani, J. 한국외국어대학교(글로벌캠퍼스) 아프리카연구소 2014 Asian Journal of African Studies Vol.35 No.-

Natural environment and socio-economic dimensions are interdependent because people get their basic needs from the environment, and inversely, for the integrity of the environment to be sustained, livelihood practices must become environmental friendly. Deterioration of environment and livelihoods interests in the Matengo highlands in Mbinga district triggered farmer-based initiatives through the facilitation of external based development partners. However, while farmers have organised themselves into groups in attempt to address the experienced livelihood-environment challenges since 2002, scant information exists on the role of farmers’ groups in that regard and hence this is the rationale for the present article. Using satellite data the article first substantiates the contention on deterioration of the natural environment by estimating the change in forest cover. Then, the role of farmers’ groups in improving the livelihood and conserving the environment is unveiled through focus group discussion, key informant interviews, informal interviews and observation methods. Consequently, recommendations are given as a way forward for improving the harmony between livelihood integrity and the sustainability of the natural environment.

Rice Os9BGlu31 Is a Transglucosidase with the Capacity to Equilibrate Phenylpropanoid, Flavonoid, and Phytohormone Glycoconjugates

Luang, Sukanya,Cho, Jung-Il,Mahong, Bancha,Opassiri, Rodjana,Akiyama, Takashi,Phasai, Kannika,Komvongsa, Juthamath,Sasaki, Nobuhiro,Hua, Yan-ling,Matsuba, Yuki,Ozeki, Yoshihiro,Jeon, Jong-Seong,Cairns American Society for Biochemistry and Molecular Bi 2013 The Journal of biological chemistry Vol.288 No.14

<P>Glycosylation is an important mechanism of controlling the reactivities and bioactivities of plant secondary metabolites and phytohormones. Rice (<I>Oryza sativa</I>) Os9BGlu31 is a glycoside hydrolase family GH1 transglycosidase that acts to transfer glucose between phenolic acids, phytohormones, and flavonoids. The highest activity was observed with the donors feruloyl-glucose, 4-coumaroyl-glucose, and sinapoyl-glucose, which are known to serve as donors in acyl and glucosyl transfer reactions in the vacuole, where Os9BGlu31 is localized. The free acids of these compounds also served as the best acceptors, suggesting that Os9BGlu31 may equilibrate the levels of phenolic acids and carboxylated phytohormones and their glucoconjugates. The Os9BGlu31 gene is most highly expressed in senescing flag leaf and developing seed and is induced in rice seedlings in response to drought stress and treatment with phytohormones, including abscisic acid, ethephon, methyljasmonate, 2,4-dichlorophenoxyacetic acid, and kinetin. Although site-directed mutagenesis of Os9BGlu31 indicated a function for the putative catalytic acid/base (Glu<SUP>169</SUP>), catalytic nucleophile residues (Glu<SUP>387</SUP>), and His<SUP>386</SUP>, the wild type enzyme displays an unusual lack of inhibition by mechanism-based inhibitors of GH1 β-glucosidases that utilize a double displacement retaining mechanism.</P>