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Identification of Secondary Metabolites in Tunisian Tilia platyphyllos Scop.Using MALDI-TOF and GC-MS

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Journal of Renewable Materials 2024年第4期12卷 827-842页

作者： Ayda Khadhri Mohamed Mendili Marwa Bannour-Scharinger Eric Masson Antonio Pizzi University of El-Manar II Faculty of SciencesPlantSoilEnvironment Interactions LaboratoryCampus AcademiaTunis2092Tunisia LERMAB University of Lorraine27 Rue Philippe SeguinEpinal88000France

This study is the first to evaluate the phytochemical content and biological properties of Tunisian T.platyphyllos Scop.A total of 23 compounds of essential oils were identified by gas chromatography-mass spectrometry(GC-MS)analysis of bracts and fruit extracts.The results show that oxygenated monoterpenes were the dominant class of essential oils.The phenolic composition was investigated by matrix-assisted laser desorption/ionizationtime of flight(MALDI-TOF).The analysis showed that the chemical profiles of the ethanolic extracts of bracts and fruits are substantially similar.The highest polyphenol content was found in the ethanolic extracts of the fruits(7.65 mg gallic acid equivalents(GAE).g−1 on dry weight(DW).As for the antioxidant capacity,it was recorded in the essential oils of the fruits(IC_(50)=0.91 mg.mL^(−1)).The results obtained showed that the antioxidant activity of the fruit essential oil was higher than that of the ethanol extract.The fruit essential oil was also found to have the highest reducing power(IC_(50)=0.67 mg.mL^(−1)).In terms of iron-chelating power,fruit essential oil has the highest chelating power(IC_(50)=2.03 mg.mL^(−1)).Compared to the ethanolic extract,the essential oil had the maximum antioxidant capacity.The enzymatic activity of acetylcholinesterase(AChE)inhibition of the essential oil from T.platyphyllos bracts had the most potent inhibitory effect(IC_(50)=0.77 mg.mL^(−1)),followed by the essential oil from the fruits(IC_(50)=0.95 mg.mL^(−1)).The results suggest that T.platyphyllos can be used as a potential source of naturally occurring bioactive compounds and antioxidants.

关键词： T.platyphyllos antioxidant activity acetylcholinesterase inhibition essential oil MALDI-TOF GC-MS

The RNA-binding domain of DCL3 is required for long-distance RNAi signaling

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aBIOTECH 2024年第1期5卷 17-28页

作者： Jie Li Bo-Sen Zhang Hua-Wei Wu Cheng-Lan Liu Hui-Shan Guo Jian-Hua Zhao State Key Laboratory of Plant Genomics Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China CAS Center for Excellence in Biotic interactions University of the Chinese Academy of SciencesBeijing 100049China Qilu Zhongke Academy of Modern Microbiology Technology Jinan 250022China

Small RNA(sRNA)-mediated RNA silencing(also known as RNA interference,or RNAi)is a conserved mechanism in eukaryotes that includes RNA degradation,DNA methylation,heterochromatin formation and protein translation repression.In plants,sRNAs can move either cell-to-cell or systemically,thereby acting as mobile silencing signals to trigger noncell autonomous silencing.However,whether and what proteins are also involved in noncell autonomous silencing have not been elucidated.In this study,we utilized a previously reported inducible RNAi plant,PDSi,which can induce systemic silencing of the endogenous PDS gene,and we demonstrated that DCL3 is involved in systemic PDS silencing through its RNA binding activity.We confirmed that the C-terminus of DCL3,including the predicted RNA-binding domain,is capable of binding short RNAs.Mutations affecting RNA binding,but not processing activity,reduced systemic PDS silencing,indicating that DCL3 binding to RNAs is required for the induction of systemic silencing.Cucumber mosaic virus infection assays showed that the RNA-binding activity of DCL3 is required for antiviral RNAi in systemically noninoculated leaves.Our findings demonstrate that DCL3 acts as a signaling agent involved in noncell autonomous silencing and an antiviral effect in addition to its previously known function in the generation of 24-nucleotide sRNAs.

关键词： RNAi signaling DCL3 RBD RNAs Cucumber mosaic virus

The combined effect of bromadiolone and ivermectin (iBr) in controlling both rodents and their fleas

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Integrative Zoology 2024年第1期19卷 156-164页

作者： Ming LIU Xinrong WAN Wei LIU Xingan MA Zhibin ZHANG State Key Laboratory of Integrated Pest Management Institute of ZoologyChinese Academy of SciencesBeijingChina CAS Center for Excellence in Biotic interactions University of Chinese Academy of SciencesBeijingChina Inner Mongolia Minzu University TongliaoInner MongoliaChina International Society of Zoological Sciences BeijingChina

Rodent pests not only cause severe agricultural loss but also spread zoonotic pathogens to human beings.Antico-agulant rodenticides are widely used to decrease the population densities of rodents but often lead to the spillover of ectoparasites becausefleas and ticks may gather on surviving rodents.Therefore,it is necessary to killfleas and ticks before culling rodents to minimize the risk of pathogen transmission.In this study,we used a mixture of ivermectin(an antiparasitic drug)and bromadiolone(an anticoagulant rodenticide)to control both rodent andflea/tick abundances.We found that in a laboratory test,0.01%ivermectin bait was not lethal for greater long-tailed hamsters after 7 days of treatment,while 0.1%ivermectin bait was lethal for approximately 33%of treated rodents.In afield test,bait containing 0.001%,0.005%,0.01%,and 0.05%ivermectin decreased the number offleas per vole of Brandt’s voles to 0.42,0.22,0.12,and 0.2,respectively,compared with 0.77 in the control group,indicating that 0.01%ivermectin bait performed best in removingfleas.In another laboratory test,bait containing a 0.01%ivermectin and 0.005%bromadiolone mixture caused the death of all voles within 6–14 days after the intake of the bait.In thefield test,the bait containing 0.01%ivermectin and 0.005%bromadiolone reduced the average number offleas per vole to 0.35,which was significantly lower than the 0.77 of the control group.Our results indicate that a 0.01%ivermectin and 0.005%bromadiolone mixture could be used to control both rodents andfleas to minimize the spillover risk of disease transmission when using traditional rodenticides.

关键词： bromadiolone flea iBr ivermectin rodent synergistic control

Gradient-induced long-range optical pulling force based on photonic band gap

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Light(Science & Applications) 2024年第5期13卷 865-874页

作者： Wenlong Lu Alexey V.Krasavin Sheng Lan Anatoly V.Zayats Qiaofeng Dai Guangdong Basic Research Center of Excellence for Structure and Fundamental interactions of Matter Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and DevicesSchool of Information and Optoelectronic Science and EngineeringSouth China Normal UniversityGuangzhou 510006China Department of Physics and London Centre for Nanotechnology King’s College LondonLondon WC2R 2LSUK

Optical pulling provides a new degree of freedom in optical manipulation.It is generally believed that long-range optical pulling forces cannot be generated by the gradient of the incident field.Here,we theoretically propose and numerically demonstrate the realization of a long-range optical pulling force stemming from a self-induced gradient field in the manipulated object.In analogy to potential barriers in quantum tunnelling,we use a photonic band gap design in order to obtain the intensity gradients inside a manipulated object placed in a photonic crystal waveguide,thereby achieving a pulling force.Unlike the usual scattering-type optical pulling forces,the proposed gradient-field approach does not require precise elimination of the reflection from the manipulated objects.In particular,the Einstein-Laub formalism is applied to design this unconventional gradient force.The magnitude of the force can be enhanced by a factor of up to 50 at the optical resonance of the manipulated object in the waveguide,making it insensitive to absorption.The developed approach helps to break the limitation of scattering forces to obtain longrange optical pulling for manipulation and sorting of nanoparticles and other nano-objects.The developed principle of using the band gap to obtain a pulling force may also be applied to other types of waves,such as acoustic or water waves,which are important for numerous applications.

关键词： optical waveguide scattering

Spin-polarized pairing induced by the magnetic field in the Bernal bilayer graphene

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Chinese Physics B 2024年第4期33卷 650-654页

作者：黄妍周涛 Guangdong Basic Research Center of Excellence for Structure and Fundamental interactions of Matter Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum MaterialsSchool of PhysicsGuangdong-Hong Kong Joint Laboratory of Quantum Matterand Frontier Research Institute for PhysicsSouth China Normal UniversityGuangzhou 510006China

Recent experimental findings have demonstrated the occurrence of superconductivity in Bernal bilayer graphene when induced by a magnetic field.In this study,we conduct a theoretical investigation of the potential pairing symmetry within this superconducting system.By developing a theoretical model,we primarily calculate the free energy of the system with p+ip-wave parallel spin pairing,p+ip-wave anti-parallel spin pairing and d+i d-wave pairing symmetry.Our results confirm that the magnetic field is indeed essential for generating the superconductivity.We discover that the p+ip-wave parallel spin pairing leads to a lower free energy for the system.The numerical calculations of the energy band structure,zero-energy spectral function and density of states for each of the three pairing symmetries under consideration show a strong consistency with the free energy results.

关键词： superconductivity magnetic field induction pairing symmetry Bernal bilayer graphene

Effects of simulated gut pH environment on bacterial composition and pheromone production of Dendroctonus valens

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Insect Science 2024年第1期31卷 225-235页

作者： Qingjie Cao Yu Zhao Tuuli-Marjaana Koski Huiping Li Jianghua Sun College of Forestry Hebei Agricultural UniversityBaodingHebei ProvinceChina State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijingChina College of Life Science/Hebei Basic Science Center for Biotic interactions Institute of Life Science and Green DevelopmentHebei UniversityBaodingHebei ProvinceChina

Bark beetles are an economically and ecologically important insect group,with aggregation behavior and thus host colonization success depends on pheromone-mediated communication.For some species,such as the major invasive forest pest in China,red turpentine beetle(Dendroctonus valens),gut microbiota participates in pheromone production by converting tree monoterpenes into pheromone products.However,how variation in gut microenvironment,such as pH,affects the gut microbial composition,and consequently pheromone production,is unknown.In this study,we fed wild caught D.valens with 3 different pH media(main host diet with natural pH of 4.7;a mildly acidic diet with pH 6 mimicking the beetle gut pH;and highly acidic diet with pH 4),and measured their effects on the gut pH,bacterial community and production of the main aggregation and anti-aggregation pheromone(verbenone).We further tested the verbenone production capacity of 2 gut bacterial isolates in different pH environments(pH 6 and 4).Compared to natural state or main host diet,feeding on less acidic diet(pH 6)diluted the acidity of the gut,whereas feeding on highly acidic diet(pH 4)enhanced it.Both changes in gut pH reduced the abundance of dominant bacterial genera,resulting in decreased verbenone production.Similarly,the highest pheromone conversion rate of the bacterial isolates was observed in pH mimicking the acidity in beetle gut.Taken together,these results indicate that changes in gut pH can affect gut microbiota composition and pheromone production,and may therefore have the potential to affect host colonization behavior.

关键词： Dendroctonus valens gut bacteria gut pH verbenone

Impact of mechanical compaction on crop growth and sustainable agriculture

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 243-252页

作者： Zijian LONG Yifei WANG Baoru SUN Xiaoyan TANG Kemo JIN College of Resources and Environmental Sciences National Academy of Agriculture Green DevelopmentKey Laboratory of Plant–Soil Interactions(Ministry of Education)China Agricultural UniversityBeijing 100193China College of Resources Sichuan Agricultural UniversityChengdu 611130China

With the development of agricultural technology to meet the growing demands of a rapidly increasing population and economic development,intensive agriculture practices have been widely adopted globally. However,this intensification has resulted in adverse consequences for soil structure due to intensified farming activities and increased usage of heavy farm machinery.Of particular concern is soil compaction, which leads to the degradation of physical, chemical and biological properties of the soil. Soil compaction negatively impacts crop growth, reduces yields and poses a significant threat to food security and the overall sustainability of agricultural systems.Recognizing these challenges, this review aims to deepen understanding of the factors contributing to soil compaction and to develop effective mitigation strategies. By doing so, it is intended to attenuate the adverse impacts of soil compaction, improve soil structure, increase crop yield and ultimately enhance the sustainability of agricultural practices.

关键词： Soil compaction mechanical compaction bio-tillage agricultural production

Effect of biochar application on rice,wheat,and corn seedlings in hydroponic culture

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Journal of Environmental Sciences 2024年第1期135卷 379-390页

作者： Yingjie Yin Jikai Li Sihang Zhu Qing Chen Chong Chen Yukui Rui Jianying Shang College of Land Science and Technology China Agricultural UniversityKey Laboratory of Plant-Soil InteractionsMinistry of Educationand Key Laboratory of Arable Land Conservation in North ChinaMinistry of Agriculture and Rural AffairsBeijing 100193China Agricultural Management Institute Ministry of Agriculture and Rural AffairsBeijing 102208China College of Resources and Environmental Sciences China Agricultural UniversityBeijing Key Laboratory of Farmland Soil Pollution Prevention and RemediationBeijing 100193China

In recent years,biochar has attracted considerable attention for soil quality improvement and carbon sequestration due to its unique physicochemical properties.However,the mechanism by which biochar application negatively affects the growth of crop seedlings has not been fully investigated.In this study,a hydroponic experiment was conducted to evaluate the response of rice,wheat,and corn seedlings to biochar application(CK,0 g/L;BC1,0.5 g/L;and BC2,1.0 g/L).Compared with the CK treatment,the BC1 and BC2 treatments decreased the fresh shoot and root weights of rice and corn seedlings(P0.05).For the contents of nutrient elements in seedlings,both BC1 and BC2 treatments hindered the roots from absorbing Fe and Cu and increased the uptake of Ca and Mn.Compared with the CK treatment,the translocation factor(TF)values of Ca,Mn,and Zn were significantly decreased especially in rice seedlings(35.3%-36.8%,68.7%-76.5%,and 29.8%-22.0%,respectively)under the BC1 and BC2 treatments,while only Mn was significantly decreased in wheat and corn seedlings(P<0.05).Transmission electron microscope(TEM)analysis of root cross-sections showed that nano-sized biochar particles(10~23 nm)were found in the root cells under BC2 treatment conditions.Our findings reveal that a large amount of biochar application can reduce nutrient absorption and translocation,and hinder rice,wheat,and corn seedlings,particularly rice seedling,in hydroponic system.

关键词： Biochar Toxicity Seedling growth Hydroponic cultivation

Large-scale interplant exchange of macromolecules between soybean and dodder under nutrient stresses

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Plant Diversity 2024年第1期46卷 116-125页

作者： Jingxiong Zhang Shalan Li Wenxing Li Zerui Feng Shuhan Zhang Xijie Zheng Yuxing Xu Guojing Shen Man Zhao Guoyan Cao Xuna Wu Jianqiang Wu Department of Economic Plants and Biotechnology Yunnan Key Laboratory for Wild Plant ResourcesKunming Institute of BotanyChinese Academy of SciencesKunming 650201China CAS Center for Excellence in Biotic interactions University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Conservation and Utilization of Bio-Resources in Yunnan and Center for Life Science School of Life SciencesYunnan UniversityKunming 650500China

Parasitic plants and their hosts communicate through haustorial connections.Nutrient deficiency is a common stress for plants,yet little is known about whether and how host plants and parasites communicate during adaptation to such nutrient stresses.In this study,we used transcriptomics and proteomics to analyze how soybean(Glycine max)and its parasitizing dodder(Cuscuta australis)respond to nitrate and phosphate deficiency(-N and-P).After-N and-P treatment,the soybean and dodder plants exhibited substantial changes of transcriptome and proteome,although soybean plants showed very few transcriptional responses to-P and dodder did not show any transcriptional changes to either-N or-P.Importantly,large-scale interplant transport of mRNAs and proteins was detected.Although the mobile mRNAs only comprised at most 0.2%of the transcriptomes,the foreign mobile proteins could reach 6.8%of the total proteins,suggesting that proteins may be the major forms of interplant communications.Furthermore,the interplant mobility of macromolecules was specifically affected by the nutrient regimes and the transport of these macromolecules was very likely independently regulated.This study provides new insight into the communication between host plants and parasites under stress conditions.

关键词： Cuscuta Mobile molecules Nutrient deficiency host plant-parasitic plant interaction Interplant transport Systemic signaling