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Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第1期68卷 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang Zhi-Li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids

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Atmospheric reductive catalytic fractionation of lignocellulose integrated with one-pot catalytic conversion of carbohydrate yielding valuable lignin monomers and platform chemicals from corn straw

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Green Energy & Environment 2025年第1期10卷 161-172页

作者： Meng-Ying Liu Zhe-Hui Zhang Xue-Qi Wang Qian Sun Chen Zhang Yu Li Zhuohua Sun Katalin Barta Feng Peng Tong-Qi Yuan State Key Laboratory of Efficient Production of forest Resources Beijing Forestry UniversityBeijing100083China Beijing Key Laboratory of Lignocellulosic Chemistry Beijing Forestry UniversityBeijing100083China department of Chemistry Organic and Bioorganic ChemistryUniversity of GrazHeinrichstrasse 28/II8010 GrazAustria

Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent ***,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps *** key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney Ni catalyst and high boiling point ethylene *** utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling *** the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%.

关键词： Atmospheric reductive catalytic fractionation Corn straw Ethylene glycol Raney Ni 5-Methoxymethylfurfural

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Smart Cellulose‑Based Janus Fabrics with Switchable Liquid Transportation for Personal Moisture and Thermal Management

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Nano-Micro Letters 2025年第1期17卷 333-347页

作者： Jianfeng Xi Yanling Lou Liucheng Meng Chao Deng Youlu Chu Zhaoyang Xu Huining Xiao Weibing Wu Jiangsu Co‑Innovation Center of Efficient Processing and Utilization of forest Resources International Innovation Center for Forest Chemicals and MaterialsJiangsu Provincial Key Lab of Sustainable Pulp and Paper Technology and Biomass MaterialsNanjing Forestry UniversityNanjing 210037People’s Republic of China College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037People’s Republic of China department of Chemical Engineering University of New BrunswickFrederictonNB E3B 5A3Canada Macromolecular Chemistry and Bavarian Polymer Institute University of BayreuthBayreuth 95440Germany

The Janus fabrics designed for personal moisture/thermal regulation have garnered significant attention for their potential to enhance human ***,the development of smart and dynamic fabrics capable of managing personal moisture/thermal comfort in response to changing external environments remains a ***,a smart cellulose-based Janus fabric was designed to dynamically manage personal moisture/*** cotton fabric was grafted with N-isopropylacrylamide to construct a temperature-stimulated transport ***,hydrophobic ethyl cellulose and hydrophilic cellulose nanofiber were sprayed on the bottom and top sides of the fabric to obtain wettability *** fabric exhibits anti-gravity directional liquid transportation from hydrophobic side to hydrophilic side,and can dynamically and continuously control the transportation time in a wide range of 3–66 s as the temperature increases from 10 to 40℃.This smart fabric can quickly dissipate heat at high temperatures,while at low temperatures,it can slow down the heat dissipation rate and prevent the human from becoming too *** addition,the fabric has UV shielding and photodynamic antibacterial properties through depositing graphitic carbon nitride nanosheets on the hydrophilic *** smart fabric offers an innovative approach to maximizing personal comfort in environments with significant temperature variations.

关键词： Directional water transport Cotton fabric Anti-gravity directional liquid transportation Janus wettability

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Biomass and carbon stocks in mangrove ecosystems of Kerala,southwest coast of India

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Ecological Processes 2020年第1期9卷 355-363页

作者： K.M.Harishma S.Sandeep V.B.Sreekumar department of forest botany Kerala Forest Research InstitutePeechiKerala 680653India department of Soil Science Kerala Forest Research InstitutePeechiKerala 680653India

Background:Mangroves are important tropical carbon sinks,and their role in mitigating climate change is well documented across the ***,the ecosystem carbon stocks in the mangroves of India have not been studied *** from this region is very limited for providing sufficient insights and authentic evaluation of carbon stocks on a regional *** this study,we evaluated the ecosystem carbon stock and its spatial variation in mangroves of Kerala,southwest coast of ***:The mean biomass stored in mangrove vegetation of Kerala is 117.11±1.02 t/ha(ABG=80.22±0.80,BGB=36.89±0.23 t/ha).Six mangrove species were found distributed in the study *** the different species,Avicennia marina had the highest biomass(162.18 t/ha)and least biomass was observed in Sonneratia alba(0.61 t/ha).The mean ecosystem carbon stock of mangrove systems in Kerala was estimated to be 139.82 t/ha,equivalent to 513.13 t CO2 e/ha with the vegetation and soil storing 58.56 t C/ha and 81.26 t C/ha ***:The present study reveals that Kerala mangroves store sizable volume of carbon and therefore need to be preserved and managed sustainably,to retain along with the increase in carbon *** features the need of broadening mangrove cover as well as restoring deteriorated land in the past 50 *** mangrove forests in this region are protected by the Kerala forest department,they have been frequently facing illegal encroachment,prawn cultivation,and coastal erosion.

关键词： Mangrove ecosystem Biomass Aboveground carbon Belowground carbon Ecosystem carbon stock

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Comparative tree-ring anatomy of Fraxinus excelsior with Chalara dieback

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Journal of forestry Research 2018年第6期29卷 1741-1749页

作者： Mirela Tulik Barbaros Yaman Nesibe Kose department of forest botany Warsaw University of Life Sciences– SGGWWarsaw 02-787Poland Wood Anatomy and Dendrochronology Laboratory Bartin UniversityFaculty of ForestryBartinTurkey department of forest botany Istanbul UniversityFaculty of Forestry34473 IstanbulTurkey

We tested the hypothesis that the biometrical characters of wood elements in ash trees(Fraxinus excelsior L.) become modified in response to the progression of disease caused by Chalara fraxinea. Anatomical analyses were performed on wood samples collected at breast height from the trunks of groups of ash trees which contained healthy, weakened and dead trees. We measured(1) treering width,(2) earlywood vessel diameter,(3) earlywood vessel element length,(4) fibre length,(5) fibre diameter,(6) fibre lumen diameter, and(7) fibre wall thickness. We showed that tree-ring width diminished in all analysed groups during disease progression. However, the greatest suppression of growth was observed in dead trees. In both weakened and dead ash trees, the reduction in tree-ring width was accompanied by diminished vessel diameter in the earlywood of the outermost annual rings. The annual rings of dead trees had shorter fibres having greater lumen diameter and thinner cell walls. Consequently, water conduction in the sapwood of dead ash trees was less efficient owing to reduced vessel diameter, and this seems to be one of the greatest disease-induced morphological modifications. All the anatomical modifications might be due to leaf loss and crown dieback triggered by Chalara fraxinea.

关键词： Ash Dieback Fibres Vessels Wood

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The Potential Contribution of Wildlife Sanctuary to forest Conservation: A Case Study from Binsar Wildlife Sanctuary

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Journal of Mountain Science 2013年第5期10卷 854-865页

作者： Balwant RAWAT Vikram S.NEGI Janhvi MISHRA RAWAT Lalit M.TEWARI Laxmi RAWAT G.B. Pant Institute of Himalayan Environment and Development Kosi-Katarmal forest Research Institute DehradunMolecular TaxonomyBotany Division department of botany D.S.B. CampusKumaun University forest Research Institute DehradunForest Ecology and Environment Division

forest vegetation of a protected area （Binsar Wildlife Sanctuary） in Kumaun region （west Himalaya） was analysed for structure, composition and representativeness across three different altitudinal belts, lower （1,6oo-1,8oo m a.s.1.）, middle （1,900-2,100 m a.s.1.） and upper （2,200-2,400 m a.s.1.） during 2oo9-2011 using standard phytosociological methods. Four aspects （east, west, north and south） in each altitudinal belt were chosen for sampling to depict maximum representation of vegetation in the sanctuary. Population structure and regeneration behaviour was analysed seasonally for two years to show the establishment and growth of tree species. A total of 147 plant species were recorded from the entire region of which 27 tree species were selected for detailed study. Highest number was recorded at upper （18 species）, and lowest at lower altitudinal belt （15 species）. The relative proportion of species richness showed higher contribution of tree layer at each altitudinal belt. The population structure, based on the number of individuals, revealed a greater proportion of seedling layer at each altitudinal belt. The relative proportion of seedlings increases significantly along altitudinal belts （p〈0.05） while opposite trends were observed in sapling and tree layers. The density of sapling and seedling species varied non-significantly across seasons （p〉0.05）. The density values decreased in summer and increased during rainy season. As far as the regeneration status is concerned, middle and upper altitudinal belts showed maximum number of species with fair regeneration as compared to lower altitudinal belt. Overall density diameter distribution of tree species showed highest species density and richness in the smallest girth class and decreased in the succeeding girth classes. This study suggests that patterns of regeneration behaviour would determine future structural and compositional changes in the forest communities. It is suggested that the compositional changes v

关键词： Altitudinal gradient Populationstructure Regeneration status West Himalaya Wildlife Sanctuary.

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Comparative Evaluation and Performance Analysis of Heat Exchangers Featured with Peened Surface

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Journal of Thermal Science 2025年第1期34卷 50-61页

作者： DINESHBABU Chinnadurai SHIVA SANKARAN Nallasamy VENKATESH RAJA Krishnan VENKATESH Rathinavelu department of Mechanical Engineering Kongunadu College of Engineering and Technology department of Mechanical Engineering Selvam College of Technology department of Mechanical Engineering Sona College of Technology department of Mechanical Engineering Saveetha School of EngineeringSaveetha Institute of Medical and Technical Sciences (SIMATS)Saveetha University

Heat exchangers have the potential for various engineering applications,and their performance is enriched by surface *** proposed system enriches the heat exchanger's performance by adapting a peened stainless steel（SS） surface blasted with copper,grinding,sand,and *** influences peened SS surface modified with a copper blast,grinding,sandblast,and iron blast on the surface morphology of shell and tube heat exchanger surface（STHE） is analyzed via tungsten heated cathode electron gun featured scanning electron microscope and observed coarse grain *** SS surface featured STHE performance is experimentally evaluated by different flow rates（30,60,90,and 120 L/min） underwater fluid medium functioned by the temperature ranges of 25-75℃ and its results are compared with computational fluid dynamic（CFD）/heat transfer research（HTRI） analyzed *** 60 L/min flow rate was spotted as an optimum value for both shell and tube side *** STHE is operated with a 60 L/min flow rate under the different peened surfaces and evaluated its Stanton number,Nusselt number,logarithmic mean temperature difference（LMTD）,overall heat transfer coefficient,number of transfer units（NTU）,effectiveness,and exergy *** iron blasted SS peened surface was observed to have better SHTE performance like Stanton number（0.0012）,Nusselt number（2180）,reduced LMTD of 31℃,improved overall heat transfer co-efficient of 2400 W/（m2·K）,better NTU of 0.5532,good effectiveness value of 0.451 62,and hiked exergy efficiency of 10% respectively.

关键词： penned surface performance analysis shell and tube heat exchanger stainless steel

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Phytotoxic effect of Sesbania virgata(Cav.) *** seeds of agronomic and forestry species

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Journal of forestry Research 2015年第2期26卷 339-346页

作者： Vera Lygia El Id Bárbara Vale da Costa Daiane Salete Broch Mignoni Marina Belloni Veronesi Kelly Simoes Marcia Regina Braga Nelson Augusto dos Santos Junior Seed department Institute of Botany Plant Physiology and Biochemistry department Institute of Botany

Sesbania virgata（Cav.） *** a pioneer species native to South America able to release allelochemicals that affect germination and development of other plant *** aim of this work was to evaluate the allelopathic effect of *** on the germination and development of co-occurring species from gallery forest and on agronomic *** forest native species,Enterolobium contortisiliquum（Vell.） Morong and Sapindus saponaria L.,and two agronomic species（these as control）,Oryza sativa *** Solanum lycopersicum *** used in the lab and greenhouse assays with seeds and leaf extracts of *** species were more affected than native species when co-germinated with seeds of *** germination percentage and speed germination index of the agronomic species were reduced in both in vitro and greenhouse *** the same assays,the seeds of native species showed no significant differences in the parameters ***,the initial growth of the four species assayed was affected,with reduction in plant length and shoot diameter followed by significant reduction in plantlet shoot and root *** the assays with irrigation of *** leaf extracts,no significant inhibitory effects on germination were observed for all *** and shoot diameter of the native species were not affected by the leaf extracts,nor were fresh and dry ***,these parameters increased in the agronomic species as they were irrigated with leaf *** on our data we conclude that seed leachates of *** affect germination and seedling development of other species,suggesting that its invasive behavior is due mainly to seed *** with less pronounced effects on native species,allelopathy of *** might also influence Interspecific competition in its natural environment.

关键词： Allelochemicals Allelopathy Catechin Fabaceae Gallery forest

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Vegetation Geo-climatic Zonation in the Rocky Mountains, Northern Utah, USA

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Journal of Mountain Science 2014年第3期11卷 656-673页

作者： Antonin KUSBACH Helga VAN MIEGROET Janis L.BOETTINGER James N.LONG department of Wildland Resources and Ecology Center Utah State University Utah State University department of forest botany Dendrology and Geobiocoenology Mendel University in Brno

We developed a vegetation geo-climatic zonation incorporating the zonal concept, gradient and discriminant analysis in Wasatch Range, northern Utah, USA. Mountainous forest ecosystems were sampled and described by vegetation, physiographic features and soil properties. The Snowpack Telemetry and National Weather Service Cooperative Observer Program weather station networks were used to approximate the climate of sample plots. We analysed vegetation and environmental data using clustering, ordination, classification, and ANOVA techniques to reveal environmental gradients affecting a broad vegetation pattern and discriminate these gradients. The specific objective was to assess and classify the response of the complex vegetation to those environmental factors operating at a coarse-scale climatic level. Ordination revealed the dominant role of regional, altitude-based climate in the area. Based on vegetation physiognomy, represented by five tree species, climatic data and taxonomic classification of zonal soils, we identified two vegetation geo-climatic zones:(1) a montane zone, with Rocky Mountain juniper and Douglas-fir; and(2) a subalpine zone, with Engelmann spruce and subalpine fir as climatic climax species. Aspen was excluded from the zonation due to its great ecological amplitude. We found significant differences between the zones in regional climate and landformgeomorphology/soils. Regional climate was represented by elevation, precipitation, and air and soil temperatures; and geomorphology by soil types. This coarse-scale vegetation geo-climatic zonation provides a framework for a comprehensive ecosystem survey, which is missing in the central Rocky Mountains of the United States. The vegetation-geoclimatic zonation represents a conceptual improvement on earlier classifications. This framework explicitly accounts for the influence of the physical environment on the distribution of vegetation within a complex landscape typical of the central Rocky Mountains an

关键词： Ecological classification Ecosystemsurvey Land classification Zonal concept Vegetation zone Vegetation geo-dimatic zone Climate change

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Syncytes during male meiosis resulting in 2n pollen grain formationin Lindelofia longiflora ***

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Journal of Systematics and Evolution 2011年第5期49卷 406-410页

作者： Vijay Kumar SINGHAL Pawan Kumar RANA Puneet KUMAR department of botany Punjabi University

Lindelofia longiflora(Royle ex Benth.) ***(Cl.) Brand(Family:Boraginaceae) is investigated cytologically(n = 12) for the first time from the cold deserts of Pangi Valley,Chamba District(Himachal Pradesh) in *** report the formation of syncytes and 2n pollen grains in the *** meiosis,the majority of the pollen mother cells(PMCs) exhibited 12 bivalents,equal segregation of chromosomes during anaphases,regular tetrads,and normal-sized pollen grain ***,two proximate PMCs fused during the early stages of prophase-I and resulted in the formation of *** frequency of syncytes in the accession is rather low,at 25 out of 1866(1.33%).Such syncyte PMCs are detectable during meiosis due to their larger size compared to typical *** syncytes or polyploid cells showed normal 24 bivalents and depicted perfectly regular meiotic *** the products of such PMCs yield 2n or larger sized pollen grains that are almost double the size of typical normal or n pollen *** origin of syncytes as a consequence of the fusion of meiocytes during the early stages of meiosis-I could be attributed to low temperature stress conditions prevailing in the Pangi Valley,where temperature during May and June dip to below freezing,the time the plants enters the reproductive/flowering bud *** is possible that such apparently fertile 2n pollen grains originating from syncytes might play a role in the origin of intraspecific polyploids in the species.

关键词： bivalents cold deserts low temperature stress Pangi Valley PMCs pollen grains.

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