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multi-functional pharmacological credence of triterpenoid 16-hydroxy betulinic acid isolated from mikania cordata

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中国药理学与毒理学杂志 2018年第4期32卷 253-254页

作者： m. Oliur rahman Shah Alam SIDDIQUI Atiqur rahman mohammad Ahsanul AKBAR mohammad Ajmal ALI Department of Botany University of Dhaka Dhaka 1000 Bangladesh Department ofApplied Chemistry and Chemical Engineering Islamic University Kushtia 7003 Bangladesh Department of Clinical Pharmacy and Pharmacology University of Dhaka Dhaka 1

OBJECTIVE To isolate and characterize bioactive compound from traditionally important medicinal plant mikania cordata,and to investigate muti-faced pharmacological activities of the isolated *** A triterpeenoid,16-hydroxy betulinic acid(16 HBA) was isolated from mikania cordata leaf and the structure of the compound was determined by NmR spectroscopic *** activity of 16 HBA was tested by disc diffusion method and minimum inhibitory concentration(mIC) against the tested microorganisms was *** analgesic property of 16 HBA was tested using acetic acid-induced writhes in mice and hot plate thermal stimulation in *** anti-inflammatory activity was studied using carrageenin-induced paw edema *** antipyretic potential of 16 HBA was evaluated by using yeast-induced hyperthermia in *** The triterpenoid 16 HBA showed potent antibacterial activity with inhibition zone of diameter ranging from 12.0~17.5 mm and antifungal activity with mycelial growth inhibition ranges from 37.6%~54.5%.The mIC values for antibacterial and antifungal activities ranged from 31.5~125 and 250~1000 μg·mL-1 *** compound(50 and100 mg·kg^(-1) body weight) showed potent peripheral and central analgesic activity having 55.19% and41% of writhing inhibition at 90 min after administration of the compound and the highest 55.98%,79.18% elongation of reaction time,*** anti-inflammatory activity screening,the compound(100 mg·kg^(-1)) revealed the highest 77.08% edema inhibition at 4 h after administration of *** antipyretic assay,16 HBA exhibited a strong antipyretic effect in yeast-induced *** The present study confirmed that 16-hydroxy betulinic acid isolated from mikania cordata has potent antimicrobial,analgesic,anti-inflammatory and antipyretic *** results can be seen as scientific support for the traditional and folklore usage of mikania cordata in Bangladesh for the treatment of differen

关键词：药用植物薇甘菊活性化学物药物分析

Effect of Al Doping on Structural, Electrical, Optical and Photoluminescence Properties of Nano-Structural ZnO Thin Films

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Journal of materials Science & Technology 2012年第4期28卷 329-335页

作者： m. mozibur rahman m.K.R. Khan m. Rafiqul Islam m.A. Halim m. Shahjahan m.A. Hakim Dilip Kumar Saha Jasim Uddin Khan Department of Physics University of Rajshahi Rajshahi 6205 Bangladesh materials Science Division Atomic Energy Centre Dhaka Bangladesh Industrial Physical Division BCSIR Dhaka Bangladesh

The nano-structural Al-doped ZnO thin films of different morphologies deposited on glass substrate were successfully fabricated at substrate temperature of 350 ℃ by an inexpensive spray pyrolysis method. The structural, electrical, optical and photoluminescence properties were investigated. X-ray diffraction study revealed the crystalline wurtzite （hexagonal） structure of the films with nano-grains. Scanning electron microscopy （SEm） micrographs indicated the formation of a large variety of nano-structures during film growth. The spectral absorption of the films occurred at the absorption edge of -410 nm. In the present study, the optical band gap energy 3.28 eV of ZnO decreased gradually to 3.05 eV for 4 mol% of AI doping. The deep level activation energy decreased and carrier concentrations increased substantially with increasing doping. Exciting with the energy 3.543 eV （A=350 nm）, a narrow and a broad characteristic photoluminescence peaks that correspond to the near band edge （NBE） and deep level emissions （DLE）, respectively emerged.

关键词： Thin film Nano-structure ZnO Surface morphology Photolumlnescence

Antioxidant and Cytotoxic Activities of A Novel Isomeric molecule(PF5)Obtained from methanolic Extract of Pleurotus Florida mushroom

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Journal of Bioresources and Bioproducts 2021年第4期6卷 338-349页

作者： D.menaga Pattanathu K.S.m.rahman S.Rajakumar P.m.Ayyasamy Department of microbiology Periyar UniversitySalem 636011India Department of microbiology Vivekanandha College of Arts and Sciences for WomenTiruchengode 637205India Research and Development Tara Biologics LimitedWokingSurrey GU216BPUnited Kingdom Department of marine Biotechnology Bharathidasan UniversityTiruchirappalli 620024India

The Pleurotus florida is recognized as a medicinal and edible mushroom and the present study intends to reveal the active isomeric molecules from this *** *** was cultivated using different nutrient supplements:groundnut husk,maize powder,horse gram powder and coconut oil-cake *** gram supplement showed the higher mushroom yield and henceit was used for the cultivation of *** extract of *** was found to be efficient in antioxidant activity among ethanol,aqueous,ethyl acetate and hexane *** bioactive fraction 3-methoxy-4-hydroxy cinnamic acid(PF5)was isolated and purified from the methanolic extract of *** by column chromatography,thin layer chromatography(TLC)and gas chromatography-mass spectrum(GC-mS)and further it was characterized by Nuclear magnetic resonance(NmR).The PF5 was tested for its DPPH and reducing power assays,and the IC_(50) values were found to be 21.7μg/mL and 105μg/mL,*** found that the cytotoxic effect of 3-methoxy-4-hydroxy cinnamic acid was tested against the lung cancer cell line using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(mTT),sulphorodamine B(SRB)and trypan blue assays which exhibited a higher cytotoxic effect(CTC_(50),645μg/mL).These results suggested that 3-methoxy-4-hydroxy cinnamic acid from *** could be explored as a novel and potent natural antioxidant and cancer preventive agent,alternative to existing synthetic molecules.

关键词： Pleurotus florida methanolic extract Isomeric molecule Antioxidant activity Cytotoxic activity

Unraveling the nature of sensing in electrostatic mEmS gas sensors

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microsystems & Nanoengineering 2024年第3期10卷 109-117页

作者： Yasser S.Shama Sasan rahmanian Hamza mouharrar Rana Abdelrahman Alaaeldin Elhady Eihab m.Abdel-rahman Systems Design Engineering University of Waterloo200 University Ave WWaterloo N2L 3G1 ONCanada mechanical Engineering Benha Faculty of EngineeringBenha UniversityBenha 13511Egypt

This paper investigates the fundamental sensing mechanism of electrostatic mEmS gas *** compares among the responsivities of a set of mEmS isopropanol sensors before and after functionalization,and in the presence and absence of electrostatic fields when operated in static and dynamic detection *** the static mode,we found that the sensors do not exhibit a measurable change in displacement due to added *** the other hand,bare sensors showed a clear change in displacement in response to isopropanol *** the dynamic mode,functionalized sensors showed a measurable frequency shift due to the added mass of isopropanol *** the presence of strong electrostatic fields,the measured frequency shift was found to be threefold larger than that in their absence in response to the same concentration of isopropanol *** enhanced responsivity of dynamic detection allows the sensors to measure the vapor mass captured by the functional material,which is not the case for static *** detection of isopropanol by bare sensors in static mode shows that change in the medium permittivity is the primary sensing *** enhanced responsivity of dynamic mode sensors when operated in strong electrostatic fields shows that their sensing mechanism is a combination of a weaker added mass effect and a stronger permittivity *** findings show that electrostatic mEmS gas sensors are independent of the direction of the gravitational field and are,thus,robust to changes in *** is erroneous to refer to them as‘gravimetric’sensors.

关键词： mechanism electrostatic measurable

Interaction of tetradecyltrimethylammonium bromide with bovine serum albumin in different compositions: Effect of temperatures and electrolytes/urea

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Chinese Journal of Chemical Engineering 2021年第1期34卷 279-287页

作者： Joynal Abedin Shamimmahbub mohammad majibur rahman Anamul Hoque Dileep Kumar Javed masood Khan Ahmed m.El-Sherbeeny Department of Chemistry Jahangirnagar UniversitySavarDhaka 1342Bangladesh Department of Chemistry&Physics Gono BishwabidyalaySavarDhaka 1344Bangladesh Department of Environmental Sciences Jahangirnagar UniversitySavarDhaka 1342Bangladesh 4 Division of Computational Phys ics Institute for Computational ScienceTon Duc Thang UniversityHo Chi Minh CityViet Nam Faculty of Applied Sciences Ton Duc Thang UniversityHo Chi Minh CityViet Nam Department of Food Science and Nutrition Faculty of Food and Agricultural SciencesKing Saud University2460Riyadh 11451Saudi Arabia Industrial Engineering Department College of EngineeringKing Saud UniversityP.O.Box 800Riyadh 11421Saudi Arabia

Herein,the interaction of a protein,bovine serum albumin(BSA),with tetradecyltrimethylammonium bromide(TTAB,a cationic surfactant),has been investigated using the conductivity measurement technique in pure water and some sodium salts(NaCl,Na_(2) SO_(4),Na_(2) CO_(3), and Na_(3) PO_(4)) solutions at temperature range of 295.15-320.15 *** reveal that,in the plot of specific conductivity versus the concentration of TTAB,only a single critical micelle concentration(cmc) was found for the TTAB+BSA mixed system in all solvents media *** addition of BSA in aqueous TTAB solution,the value of cmc undergoes a change from its pure form,which indicates the presence of strong interaction operating between the BSA and TTAB *** aqueous system,the cmc values of the TTAB+BSA mixtures are obtained higher compared to the values found for single TTAB surfactant However,the addition of salt decreases the cmc value of mixed TTAB+BSA *** values of cmc of the BSA+TTAB mixed system at 310.15 K and 1.00 mmol·kg^(-1) ionic strength of salt followed the order:cmc_(Na_(2) CO_(3))> Cmcc_(Na_(3) PO_(4))> cmcNaCl>cmC_(Na_(2) SO_(4)).The cmc values of TTAB+BSA mixture were found to be lowered in urea solution within the concentrations *** values of degree of dissociation(α) and fraction of counter ion binding(β) were found to be dependent on additives and *** free energy of micellization(AGm) is negative for all the systems,which manifests that the micellization phenomenon is energetically *** enhancement of the negative value of △G_(m)^(0) in aqueous salt solutions reveals an increase of spontaneity of the TTAB+BSA micellization *** values of △G_(m)^(0) also reveal that the spontaneity of micelle formation is enhanced at higher temperatures in all media *** values of free energy of transfer(△G_(m,t)^(o)) were also determined for numerous solvent media used in the present study and described with appropriate reasoning.

关键词： TTAB BSA Conductivity Electrolyte Exothermic interaction

Biochar derived from invasive plants improved the pH,macronutrient availability and biological properties better than liming for acid rain-affected soil

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Biochar 2023年第1期5卷 1029-1044页

作者： Yazheng Li Ahmed I.Abdo Zhaoji Shi Abdel-rahman m.A.merwad Jiaen Zhang Department of Ecology College of Natural Resources and EnvironmentSouth China Agricultural UniversityGuangzhou 510642China Guangdong Provincial Key Laboratory of Utilization and Conservation of Food and medicinal Resources in Northern Region Yingdong College of Biology and AgricultureShaoguan UniversityShaoguan 512005China Soil Science Department Faculty of AgricultureZagazig UniversityZagazig 44519Egypt Guangdong Laboratory for Lingnan modern Agriculture Guangdong Provincial Key Laboratory of Eco-Circular AgricultureSouth China Agricultural UniversityGuangzhou 510642China Guangdong Engineering Technology Research Centre of modern Eco-Agriculture and Circular Agriculture Guangzhou 510642China

Rapid development in industrialization and urbanization causes serious environmental issues,of which acid rain is one of the quintessential hazards,negatively affecting soil *** has been investigated for a long time as the most effective amendment to alter the adverse effects of soil acidity resulting from acid ***,this study tested the biochar produced from invasive plants as an alternative amendment and hypothesized that biochar can maintain better availability of macronutrients under acid rain than liming by improving soil chemical and biological ***,a pot experiment was conducted to compare the effects of lime and biochar at two rates(1%and 3%)on soil available nitrogen(N),phosphorous(P)and potassium(K)under simulated acid rain of two pH levels(4.5:pH_(4.5) and 2.5:pH_(2.5))as compared with tap water(pH7.1)as a control *** was produced using different invasive plants,including Blackjack(Biden Pilosa),Wedelia(Wedelia trilobata)and Bitter Vine(mikania micrantha Kunth).Liming decreased the availability of soil N,P,and K by 36.3%as compared with the control due to the great increment in soil pH and exchangeable calcium(Ca^(2+))by 59%and 16-fold,***,liming reduced the alpha diversity of soil bacteria and fungi by 27%and 11%,*** contrast,biochar at different types and rates resulted in a fourfold increment in the available N,P,and K as an average under acid rain(pH_(4.5) and pH_(2.5))owing to maintaining a neutral pH(6.5-7),which is the most favorable level for soil microbial and enzymatic activites,and the bioavailability of soil ***,biochar caused balanced increments in Ca^(2+)by threefold,cation exchange capacity by 45%,urease activity by 16%,and fungal diversity by 10%,while having a slight reduction in bacterial diversity by 2.5%.Based on the path,correlation,and principal component analyses,the exchangeable aluminum was a moderator for the reductions in macronutrien

关键词： Acidic soil Liming Invasive plants Biochar feedstock Soil chemical properties

Absence of postzygotic isolating mechanisms:evidence from experimental hybridization between two species of tropical sea urchins

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第10期13卷 797-810页

作者： m.Aminur rahman Tsuyoshi UEHARA Aziz ARSHAD Fatimah md.YUSOFF mariana Nor SHAmSUDIN Laboratory of marine Biotechnology Institute of BioscienceUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Department of Chemistry Biology and Marine ScienceFaculty of ScienceUniversity of the Ryukyus1 SenbaruNishihara-choOkinawa 903-0213Japan Department of Aquaculture Faculty of AgricultureUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia

Two reef margin species of tropical sea urchins,Echinometra sp.C(Ec) and Echinometra oblonga(Eo),occur sympatrically on Okinawa intertidal reefs in southern *** between these species was examined through a series of cross-fertilization *** limited sperm concentrations,where conspecific crosses reached near 100% fertilization,both heterospecific crosses showed high fertilization rates(81%-85%).The compatibility of the gametes demonstrated that if gamete recognition molecules are involved in fertilization of these species,they are not strongly *** found that conspecific crosses reached peak fertilization levels much faster than did heterospecific crosses,indicating the presence of a prezygotic barrier to hybridization in the *** survival,metamorphosis,and juvenile and adult survival of hybrid groups were nearly identical to those of their parent *** from crosses in both directions developed normally through larval stages to sexually mature adults,indicating that neither gametic incompatibility nor hybrid inviability appeared to maintain reproductive isolation between these *** adults,Ec×Ec crosses gave the highest live weight,followed by Eo(ova)×Ec(sperm),Ec(ova)×Eo(sperm),and Eo×*** growth performance measures(viz.,test size,Aristotle's lantern length,and gonad index) of hybrid groups and their parental siblings showed the same *** phenotypic color patterns of the hybrids were closer to the maternal coloration,whereas spine length,tube-foot and gonad spicule characteristics,pedicellaria valve length,and gamete sizes showed intermediate *** F 1 hybrids were completely fertile and displayed high fertilization success in F 1 backcrosses,eliminating the likelihood that hybrid sterility is a postzygotic mechanism of reproductive ***,intensive surveys failed to find hybrid individuals in the field,suggesting the lack or rarity of natural *** stron

关键词： Sea urchins Echinometra Hybridization Gamete compatibility Reproductive isolation Speciation

A critical review of the emerging research on the detection and assessment of microplastics pollution in the coastal,marine,and urban Bangladesh

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Frontiers of Environmental Science & Engineering 2022年第10期16卷 39-52页

作者： Zaki Alam Pushan Ehsanur rahman Nafisa Islam Nirupam Aich Department of Chemical Engineering Bangladesh University of Engineering and TechnologyDhaka 1000Bangladesh Department of Civil Environmentaland Geo-EngineeringUniversity of Minnesota-Twin CitiesMinneapolisMN 55455USA Department of Civil Structural and Environmental EngineeringUniversity at BuffaloThe State University of New YorkBuffaloNY 14260USA

The research on the extent and effects of microplastics pollution in the Global South is only getting *** is a South Asian country with one of the fastest growing economies in the world,however,such exponential economic growth has also increased the pollution threats to its natural and urban *** this paper,we reviewed the recent primary research on the assessment of the extent of microplastics pollution in *** online databases,we developed a compilation of emergingresearch articles that detected and quantified microplastics in different coastal,marine,and urban environments in *** of the studies focused on the coastal environment(e.g.,beach sediment)and marine fish,while limited data were available for the urban *** also discussed the relationship of the type of anthropogenic activities with the observed microplastic *** Cox's Bazar sea beach in south-east Bangladesh experienced microplastics pollution due to tourism activities,while fishing and other anthropogenic activities led to microplastics pollution in the Bay of *** microplastics larger than 1 mm were prevalent in the beach sediments,smaller microplastics with size below 0.5 mm were prevalent in marine fish ***,the differences m microplastic abundance,size,shape,color,and polymer type found were depended on the sampling sites and relevant anthropogenic *** is imperative to identify majorsources of microplastics pollution in both natural and urban environment,determine potential environmental and human health effects,and develop mitigating and prevention strategies for reducing microplastics pollution.

关键词： Plastic pollution Waste management Global south Sustainability marine pollution

Distribution of heavy metals in water and sediment of an urban river in a developing country:A probabilistic risk assessment

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International Journal of Sediment Research 2022年第2期37卷 173-187页

作者： mir mohammad Ali Saima rahman md Saiful Islam md Refat Jahan Rakib Shaharior Hossen md Zillur rahman Tapos Kormoker Abubakr m. Idris Khamphe Phoungthong Institute of Disaster management Khulna University of Engineering and Technology Department of Aquaculture Sher-e-Bangla Agricultural University Department of Urban and Regional Planning Khulna University of Engineering and Technology Department of Soil Science Patuakhali Science and Technology University Department of Fisheries and marine Science Noakhali Science and Technology University Department of Fisheries Science Chonnam National University Quality Control Chemistry Lab Department of Fisheries Department of Emergency management Patuakhali Science and Technology University Department of Chemistry College of Science King Khalid University Research Center for Advanced materials Science (RCAmS) King Khalid University Environmental Assessment and Technology for Hazardous Waste management Research Center Faculty of Environmental Management Prince of Songkla University

River water and sediment embody environmental characteristics that give valuable eco-environmental *** to rapid industrialization,the aquatic environment of any urban river can be seriously polluted by heavy metals(Hms).The global concern is caused by heavy metal pollution because of its potential harm to aquatic ecosystems and human *** the Bhairab River,Bangladesh,surface sediment concentrations of globally alarming toxic metals such as arsenic(As),chromium(Cr),cadmium(Cd),and lead(Pb) were measured to determine the ecological and human health risks of the riverine *** average As,Cr,Cd,and Pb concentrations in water were 3.55,31.74,1.44,and23.82 μg/L,respectively,and in sediment were 4.13,34.17,1.66,and 25.46 mg/kg,*** the winter,metals in sediment were higher than during the *** most sediment samples,the enrichment factor(EF),contamination factor(CF),geoaccumulation index(I),pollution load index(PLI) of As,Cr,Cd,and Pb indicated moderate *** potential ecological risk(PER) in sediment followed the descending order of Cd> As> Pb> *** contamination level of toxic metals implied that the condition is frightening and probably severely affecting the aquatic ecology of this riverine ecosystem.

关键词： Toxic metals Environmental risk Bioaccumulation Ecological risk Bangladesh