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Biosensor analysis technology is a kind of technology with high specificity that can convert biological reactions into optical and electrical signals. In the development of drugs for Alzheimer's disease (AD), according to different disease hypotheses and targets, this technology plays an important role in confirming targets and screening active compounds. This paper briefly describes the pathogenesis of AD and the current situation of therapeutic drugs, introduces three biosensor analysis techniques commonly used in the discovery of AD drugs, such as surface plasmon resonance (SPR), biolayer interferometry (BLI) and fluorescence analysis technology, explains its basic principle and application progress, and summarizes their advantages and limitations respectively.
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This article for the first time presents the results of the study of qualitative and quantitative elemental and amino acid composition of the aboveground part of the plant Nepeta olgae Regel (L.) taken in the territory of Chust and Kosonsai districts (from the slopes of Gova and Kosonsai mountains) of Namangan region during the period before and during flowering (May-June, 2021-2022). The use of instrumental analysis of high-throughput energy dispersive X-ray fluorescence spectrometry, allowed to establish 20 mineral elements in the plant Nepeta olgae Regel (L.), among which to vital 9 elements and 3 to conditionally necessary. The amino acid composition of the plant Nepeta olgae Regel (L.) was studied by high performance liquid chromatography (HPLC) and 17 compounds were identified. Of these, 8 were substitutable and 9 essential amino acids.
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The pollution caused by improper handling of plastics has become a global challenge. In addition to recycling plastics and using biodegradable plastics, an alternative solution is to seek efficient methods for degrading plastics. Among them, the methods of using biodegradable enzymes or microorganisms to treat plastics have attracted increasing attention because of its advantages of mild conditions and no secondary environmental pollution. Developing highly efficient depolymerizing microorganisms/enzymes is the core for plastics biodegradation. However, the current analysis and detection methods cannot meet the requirements for screening efficient plastics biodegraders. It is thus of great significance to develop rapid and accurate analysis methods for screening biodegraders and evaluating biodegradation efficiency. This review summarizes the recent application of various commonly used analytical techniques in plastics biodegradation, including high performance liquid chromatography, infrared spectroscopy, gel permeation chromatography, and determination of zone of clearance, with fluorescence analysis techniques highlighted. This review may facilitate standardizing the characterization and analysis of plastics biodegradation process and developing more efficient methods for screening plastics biodegraders.
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Biodegradable Plastics/chemistry , Biodegradation, EnvironmentalABSTRACT
Objective@#To establish a fluorescence method based on turncated aptamer for the determination of bisphenol A in water.@*Methods@#The bisphenol A truncated aptamer containing 38 bases was selected as a recognition module, and was modified with the fluorophore 6-FAM at the 5'end. The 3'end of the complementary sequence cDNA was modified with the quencher DABCYL. The standard solutions of bisphenol A and interfering compounds were configured. The detection system was established after optimizing the number of bases in cDNA, the concentration ratio of truncated aptamer to cDNA, the incubation temperature and time, and the pH of the buffer. The specificity and recovery experiments were carried out. @*Results@#When the complementary sequence cDNA included 9 bases, the concentration ratio of the truncated aptamer to cDNA was 1:1.5, the pH value of the buffer solution was 7.5, the cDNA was incubated at 55 ℃ for 60 minutes, in the concentration range of 10-75 pmol/L, the linear regression equation was y=2 230.7x+110 825, the correlation coefficient was 0.926. The limits of detection was 3.3 pmol/L. The difference values of fluorescence intensity between tetrabromobisphenol A, estradiol, estriol, bisphenol S and bisphenol A were obviously different, so there was no significant interference to the test result. The recovery rates were 97.8%, 98.8% and 102.3% with the spiked concentrations of 20.0, 40.0 and 60.0 pmol/L. The relative standard deviations were 4.4%, 2.1% and 2.6% (n=5), respectively. @*Conclusion@#The fluorescence method based on turncated aptamer has the advantages of easy operation, high sensitivity and specificity, which can be used for the determination of bisphenol A in water.
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Abstract Concentrations of nickel, copper, zinc and lead in surface sediments from 16 stations located in Mampostón sub-watershed (Mayabeque, Cuba) were estimated by X-ray fluorescence analysis. The Cu, Zn and Pb contents in sediments shows a different level of contamination across the studied stations. The application of modified degree of contamination (mCd) allowed to classify the metal pollution in Ganuza and Mampostón rivers and in Pedroso reservoir. The comparison with Sediment Quality Guidelines and toxicity mean quotients shows that 100% of the sediments are associated with the occasional presence of possible adverse effects to human health.
Resumen Se determinan, por Fluorescencia de Rayos X, las concentraciones de Níquel, Cobre, Zinc y Plomo en los sedimentos superficiales de 16 estaciones en la subcuenca Mampostón (Mayabeque, Cuba).Los contenidos de Cu, Zn y Pb en los sedimentos muestran diferentes niveles de contaminación en las estaciones estudiadas. La aplicación del grado de contaminación modificado (mCd) permitió clasificar como alta o baja la contaminación de los ríos Ganuza y Mampostón, así como del embalse Pedroso. La comparación con las Guías de Calidad de Sedimentos y del cociente promedio de toxicidad, mostró que el 100% de los sedimentos estudiados están asociados a la presencia ocasional de posibles efectos adversos a la salud humana.
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Carica papaya is made to develop pharmacognostical characters of leaf with their morphological, microscopical, and physical characters including histochemical analysis. Morphological evaluation as color, odor, taste, size, shape, surface, and powder microscopy of plant shows the presence of endosperm cell which is polygonal in shape and contains aleurone grains and oil droplet, cell of testa, yellow coloring matter, and starch grains. Quantitative leaf microscopy to determine palisade ratio, stomata index, and vein-islet number is carried out. Peels are removed mechanically through epidermal peeling off and stomatal index (SI) is calculated. The vein-islet number, vein termination number, and palisade ratio of lamina are determined according to the standard method. We prepared the extracts of plant with different solvents for determining the different extractive values by maceration, Soxhlet extraction, successive extraction process, and determination of ash values, pH value, moisture content, and phytochemical screening to show the presence of carbohydrates, phenolic compounds, flavonoids, alkaloids, proteins, saponins, and lipids in the drug extract and fluorescence analysis in different solvent. Analysis of pesticide residues, aflatoxin, and heavy metals are also performed
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RESUMEN Una de las direcciones de aplicación de la Ciencia de Materiales que realiza el Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear CEADEN es el apoyo mediante un grupo de técnicas físicas a la restauración y el mantenimiento de estructuras y objetos de la ciudad de La Habana, entre otras localidades de Cuba, que poseen interés artístico y social . En el presente trabajo se abordan varias aplicaciones en la caracterización de materiales para contribuir a las actividades de conservación del patrimonio cultural e histórico cubano que se encuentra en La Habana. Se presentan dos ejemplos de análisis por las técnicas de Fluorescencia de Rayos X y Difracción de rayos X de los pigmentos de obras en lienzos y de la paleta de una reconocida artista de la plástica cubana; así como el de tejas cerámicas que fueron utilizadas en la restauración de los techos de la residencia conocida como Casa Verde de 5ta Avenida en el Municipio Playa.
ABSTRACT One of the applications in Materials Science carried out at the Center for Technological Applications and Nuclear Development (CEADEN) is the technical support through several methods used, based on applied Physics for the restoration and maintenance of structures and objects holding artistic and social relevance in Havana city. The aim of this paper is to present two examples of X -ray Fluorescence and Diffraction materials characterization, intended to support conservation and restoration activities of the Cuban cultural and historic heritage: analyzed objects were pottery roof tiles for the restoration of the mansion known as The Green House at 5th Avenue, Miramar, as well as pigments from a Cuban fine artist's canvas and palette.
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RESUMEN Se resumen las diferentes experiencias en la aplicación de las técnicas nucleares y conexas en el estudio de diversos problemas ambientales de la Ciudad de La Habana. El análisis medioambiental mediante las técnicas de Análisis por Activación Neutrónica (AAN) y Gamma (AAG), Fluorescencia de Rayos X (FRX), Espectrometría por Absorción Atómica (EAA) y por Inducción de plasma acoplado (ICP), así como la Espectrometría Gamma de Bajo Fondo (EGBF), han permitido obtener información muy relevante sobre el comportamiento de los metales pesados, antibióticos y radionúclidos en los sedimentos marinos y fluviales, suelos urbanos y agrícolas, aguas, arenas de balnearios, polvos urbanos y productos de la agricultura urbana de la ciudad de La Habana.
ABSTRACT Various nuclear and related analytical techniques applied to study different environmental problems in Havana city are presented. The environmental analysis by means of Neutron and Gamma Activation analyses, X-ray Fluorescence Atomic Abortion and Induced Coupled Plasma spectroscopies and Low Background , Gamma Spectrometry, have allowed to obtain important information about the behavior of heavy metals, antibiotics and radionuclides in sediments, urban and agricultural soils, waters, beach sands, urban dusts and agricultural products farmed in the Havana city.
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Background: Myrica esculenta (Family: Myricaceae) commonly known as Kaiphala or Katphala is a widelyused medicinal plant in Ayurveda. In spite of its numerous medicinal attributes, no published work isavailable till date on pharmacognostical characterization and HPTLC analysis of its leaves.Objectives: To investigate the pharmacognostical, physicochemical, and HPTLC profiles of M. esculentaleaves.Materials and methods: The measures taken for pharmacognostical characterization were organolepticstudy, macroscopy, microscopy, powder microscopy, leaf constant, fluorescence analysis, preliminaryphytochemical screening and HPTLC spectra profile.Results: Organoleptic and macroscopic studies found that leaves are lancoelate, thin, spirally arranged,dark green in color, with an astringent taste and acute apex. In transverse section, cuticularisedepidermis having polygonal cells were found. Mesophyll cells were differentiated into single layeredpalisade cells on each surface and 2e3 layered spongy parenchyma, unicellular and uniseriate hollowtrichomes, anomocytic stomata and bowl shaped vascular bundle in mid rib portion containing xylemand phloem tissues. Alkaloids, carbohydrates, flavonoids, glycosides, phenolic compounds and tanninswere found present. Analysis on the leaf constants, powder microscopy, fluorescence characteristics andphysical parameters resulted a valuable data to establish standards for the plant. HPTLC profile providesnumber of constituents present in the extracts with their respective Retention Factor (Rf).Conclusion: Present report on pharmacognostical characterization and HPTLC analysis of M. esculentaleaves provides a vital diagnostic tool for identification, authentication and development of quality parameters of the species. Data obtained by present study may be considered as standard for future studies.© 2017 Transdisciplinary University, Bangalore and World Ayurveda Foundation. Publishing Services byElsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
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Objective:To study and establish a method for the efficient screening of 14-3-3τ protein inhibitors from natural products, and analyze the sites of their interactions with the 14-3-3τ protein. Methods: The binding activity of natural compounds with the 14-3-3τ protein was tested by the liquid chromatography-fluorescence spectroscopy, and the binding activity of the potential compounds was further verified by the surface plasmon resonance(SPR)technique. The binding sites of the active compounds were predicted by the molecular docking technique. Furthermore, the key binding sites were selected and then validated using amino acid site-directed mutants. Results: A total of 17 different type compounds with potential 14-3-3τ binding activity were screened out from 82 natural products. The binding activi- ties of 10 compounds were verified by the SPR experiments. Then the binding sites of interactions between the 14-3-3τ protein and the 10 compounds were predicted by the molecular docking technology to be mainly at the Arg56, Arg127 and Y128A, dem- onstrate that the binding of five of the 10 compounds with the target protein was associated with the three sites Arg56, Arg127 and Tyr128. Conclusion: The established method is accurate and efficient, which could be used for rapid screening of small molecule 14-3-3τ inhibitors from natural products. The present study provides a reference and a new approach for the rapid screening of 14-3-3τ inhibitors for the new breast cancer therapeutic drugs.
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Heavy metal (Co, Ni, Cu, Zn and Pb) content in muds from some Cuban spas (San Diego, Elguea, Santa Lucía and Cajío) have been studied using X-ray fluorescence. The measured metal contents are in the same order of magnitude as those reported for average Earths upper crust average shales and muds as well as with worldwide reported peloids. The comparison with sediment quality guidelines (SQGs) shows a different degree of pollution for peloids from each studied spa. Nevertheless, the estimated sum of metal/probable effect level value ratios (0.9 - 2.4) correspond to a low potential acute toxicity of contaminants. Therefore, the heavy metal content present in peloids from the studied Cuban spas is not an obstacle for its use with therapeutic purposes
Se estudia mediante la técnica de Fluorescencia de rayos X, el contenido de metales pesados (Co, Ni, Cu, Zn y Pb) en lodos terapéuticos provenientes de varios balnearios cubanos (San Diego, Elguea, Santa Lucía y Cajío). Los contenidos de metales pesados determinados en los lodos terapéuticos se encuentran en el mismo orden que los reportados para lodos y esquistos representativos de la corteza terrestre, así como para lodos utilizados en balnearios internacionalmente. La comparación con las Guías de Calidad de sedimentos muestran diferentes grados de polución para los lodos de cada balneario. Independientemente de ello, los valores de las razones suma de metales/nivel de efecto probable (0,9-2,4) corresponden a un bajo potencial agudo de toxicidad por contaminantes. De esta manera, el contenido de metales pesados presentes en los lodos de los balnearios estudiados no representa impedimento alguno para su uso con fines terapéuticos.
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A terminal deoxynucleotidyl transferase ( TdT ) amplification based DNA-copper nanoclusters (CuNCs) sensor was developed for detection of L-histidine ( L-His). Single strand DNA containing poly-thymine ( T) sequences were synthesized by TdT in the presence of dTTP. In blank control, poly-T sequences worked as templates of CuNCs due to the affinity between thymine and copper ions( II) . Fluorescence intensity was enhanced when CuNCs formed with reducing agents. In the presence of L-His, the imidazolyl group of L-His worked as a chelating agent that formed L-His-Cu2+ chelated complex. Thus less copper ions were induced in poly-T sequences, and less CuNCs were obtained to produce week fluorescence signals. A good linear correlation was obtained between fluorescence change and the logarithm of the L-His concentration over the range of 5. 0 ×10-9-5. 0 ×10-4 mol/L. The detection limit was estimated as 3. 4 ×10-9 mol/L. And the recoveries were 97. 4%-104. 6% for the actual urine samples. Compared with other methods of synthetic CuNCs, this method allowed to specifically determining L-histidine without template or labeling, which showed good potential in biomedical and clinical analysis.
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A terminal deoxynucleotidyl transferase ( TdT ) amplification based DNA-copper nanoclusters (CuNCs) sensor was developed for detection of L-histidine ( L-His). Single strand DNA containing poly-thymine ( T) sequences were synthesized by TdT in the presence of dTTP. In blank control, poly-T sequences worked as templates of CuNCs due to the affinity between thymine and copper ions( II) . Fluorescence intensity was enhanced when CuNCs formed with reducing agents. In the presence of L-His, the imidazolyl group of L-His worked as a chelating agent that formed L-His-Cu2+ chelated complex. Thus less copper ions were induced in poly-T sequences, and less CuNCs were obtained to produce week fluorescence signals. A good linear correlation was obtained between fluorescence change and the logarithm of the L-His concentration over the range of 5. 0 ×10-9-5. 0 ×10-4 mol/L. The detection limit was estimated as 3. 4 ×10-9 mol/L. And the recoveries were 97. 4%-104. 6% for the actual urine samples. Compared with other methods of synthetic CuNCs, this method allowed to specifically determining L-histidine without template or labeling, which showed good potential in biomedical and clinical analysis.
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Concentrations of Cr, Co, Ni, Cu, Zn, Pb and Fe in the street dust from Camagüey city were studied by X-ray .uorescence analysis. The mean Cr, Co, Ni, Cu, Zn and Pb contents in the urban dust samples (97 ± 30, 14 ± 2, 35 ± 36, 94 ± 26, 199 ± 87 and 42 ± 29 mg.kg-1 dry weight, respectively) were compared with mean concentrations in other cities around the world. Spatial distribution maps indicated the same behaviour for Cr-Ni and Pb-Zn-Cu, respectively, whereas the spatial distribution of Co differs from other heavy metals. The metal-to-iron normalization, using Cuban average metal soil contents as background, showed that street dusts from Camagüey city are moderately or significantly Zn-Pb enriched in those areas associated with heavy traffic density and metallurgic plant location. However, the calculation of the potential ecological risk index shows that metal content in Camagüey street dust does not represent any risk for the city population.
Se determinan por fluorescencia de rayos X las concentraciones de Cr, Co, Ni, Cu, Zn y Pb en los polvos urbanos de la ciudad de Camagüey. Los contenidos medios de metales pesados en las muestras de polvos urbanos (97 ± 30, 14 ± 2, 35 ± 36, 94 ± 26, 199 ± 87 y 42 ± 29 mg.kg-1 en peso seco respectivamente) son comparados con las concentraciones medias determinadas en otras ciudades del mundo. Los mapas de distribución espacial indican comportamientos similares para Cr-Ni y Pb-Zn-Cu respectivamente, en tanto la distribución espacial de Co difiere del resto de los metales. La normalización a un metal de referencia, empleando como fondo los valores medios de concentraciones de metales pesados cubanos, mostró que los polvos urbanos de la ciudad de Camagüey tienen un enriquecimiento moderado o significativo de Zn y Pb en aquellas áreas que están asociadas a una elevada densidad del tráfico automotor y a la ubicación de plantas metalúrgicas. El cálculo del índice de riesgo ecológico potencial mostró que el contenido de metales pesados en los polvos urbanos de Camagüey no representa riesgo alguno para su población.
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Concentrations of chromium, nickel, copper, zinc and lead in surface sediments from six stations located in Nuevitas Bay (Cuba) were estimated by X-ray fluorescence analysis. The Cr content in sediments shows a strong variation across the studied stations (89-513 
), in contrast with the other elements studied. The application of modified degree of contamination (
) classifies as moderate the contamination of Nuevitas Bay. The comparison with Sediment Quality Guidelines (SQGs) and toxicity mean quotients shows that 100 % of the sediments are associated with the occasional presence of possible adverse effects to human health.
Se determinan, mediante el análisis por fluorescencia de rayos X, las concentraciones de cromo, níquel, cobre, zinc y plomo en sedimentos superficiales de seis estaciones de la Bahía de Nuevitas en Cuba. El contenido de cromo se determinó con un intervalo de gran variación (89-513 ) en las estaciones estudiadas. La aplicación del grado de contaminación modificado () clasificó la contaminación de los sedimentos de la Bahía de Nuevitas como de “grado moderado”. La comparación con las Guías de Calidad de Sedimentos y del cociente promedio de toxicidad, mostró que el 100 % de los sedimentos estudiados están asociados a la presencia ocasional de posibles efectos adversos a la salud humana.
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We reported a simple and fast fluorescence system based on quantum dots ( QDs ) to detect glutamate dehydrogenase ( GLDH) , which inverted glutamate to α-ketogrutarate using NAD+ as a coenzyme. The fluorescence of CdTe QDs was quenched by nicotinamide adenine dimucleotide ( NAD+) through an electron transfer pathway, and the quencher NAD+ could be consumed by adding NAD+-dependent enzymes and corresponding substrates. Based on this principle we introduced GLDH to consume NAD+ in the QDs/NAD+ system, leading to the enhancement of the fluorescence intensity of QDs, which was in proportional to the amounts of GLDH added. Using this fluorescence system, we measured GLDH in a wide concentration range from 10 U/L to 1000 U/L, which was of significance in clinical diagnosis of different kinds of liver diseases.
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Objective To investigate the similarities and differences of 3 methods for detecting hepatitis B virus S 1(PreS1) ,and select the appropriate method for detecting clinical samples .Methods The PreS1 of the serum samples from chronic hepatitis B pa-tients were tested with enzyme immunoassay analyzer ,time-resolved method and the manual method .To compare the repetition rate ,select PreS1 antigen strongly positive serum and weak positive serum were detected 15 times by three methods ;To compare the explicit rate ,the reaction temperature was raised or lowered by 3 ℃ .Results The positive rate of three methods was 93 .53% , 92 .81% ,92 .81% .Automated ELISA reproducibility CV strong positive CV3 .62% ,weakly positive CV was 13 .42% ,CV of time-resolved method for the 2 kinds of samples were 5 .10% ,7 .92% ,manual methods CV 11 .10% 29 .88% ;changing the reaction incu-bation temperature 3 ℃ ,automatic detection ELISA all specimens S/CO value decreased ,increasing the chance of a false negative . The manual methods and time-resolved detection method for all specimens S/CO values increased ,increasing the chance of a false positive .Conclusion The detection rate and repeatability of automated ELISA were better .The time-resolved method followed and the manual methods were poor .
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Objective: To evaluate the diagnostic pharmacognostical characters of Costus speciosus (aerial parts) along with their physico-chemical parameters and fluorosence analysis. Method: The pharmacognostical characters were determined in terms of macroscopy, microscopy, powder microscopy, leaf constant, fluorescence analysis and preliminary phytochemical investigation. Results: The findings of macroscopy revealed that leaves elliptic to oblong or oblong-lancoelate, thick, spirally arranged, with stem clasping sheaths up to 4 cm, flowers large, white, cone-like terminal spikes, with bright red bracts. Transverse section of leaflet showed the presence of cuticularised epidermis with polygonal cells on adaxial surface and bluntly angled cells on abaxial surface of lamina, mesophyll cells differentiated in to single layered palisade cells on each surface and 2-3 layered spongy parenchyma, unicellular and uniseriate multicellular covering trichomes, paracytic stomata and vascular bundles surrounded by sclerenchymatous multicellular sheath. Preliminary phytochemical screening exhibited the presence of various phytochemical groups like alkaloids, glycosides, steroids, phenolic constituents. Further, the leaf constants, powder microscopy and fluorescence characteristics indicated outstanding results from this investigation Conclusions: Various pharmacognostical and physico-chemical parameters have pivotal roles in identification, authentication and establishment of quality parameters of the species.
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Objective: To establish the pharmacognostic characters for the correct identification and quality control of Hilleria latifolia (H. latifolia), an important herb in Ghanaian folklore medicine, for the treatment of infections, pain and inflammation. Methods: The macro-morphological, qualitative and quantitative microscopic features, physicochemical and phytochemical features of the medicinally used parts of H. latifolia were evaluated using standard methods. Results: The plant has simple, alternate leaves with entire margin. The lamina is ovate to broadly lanceolate with an acuminate apex. It is hypostomatic with anomocytic stomata. The plant contains abundant prismatic crystals in all parts. Starch grains abound in the roots. The quantitative indices of the leaf and physicochemical parameters have also been established. Conclusions: The pharmacognostic features established in this study may be used as part of the pharmacopoeial standard for the correct identification and quality control of H. latifolia.
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Objective: To evaluate the diagnostic pharmacognostical characters of Costus speciosus (aerial parts) along with their physico-chemical parameters and fluorosence analysis.Method:microscopy, powder microscopy, leaf constant, fluorescence analysis and preliminary phytochemical investigation.Results:The findings of macroscopy revealed that leaves elliptic to oblong or oblong-lancoelate, The pharmacognostical characters were determined in terms of macroscopy, thick, spirally arranged, with stem clasping sheaths up to 4 cm, flowers large, white, cone-like terminal spikes, with bright red bracts. Transverse section of leaflet showed the presence of cuticularised epidermis with polygonal cells on adaxial surface and bluntly angled cells on abaxial surface of lamina, mesophyll cells differentiated in to single layered palisade cells on each surface and 2-3 layered spongy parenchyma, unicellular and uniseriate multicellular covering trichomes, paracytic stomata and vascular bundles surrounded by sclerenchymatous multicellular sheath. Preliminary phytochemical screening exhibited the presence of various phytochemical groups like alkaloids, glycosides, steroids, phenolic constituents. Further, the leaf constants, powder microscopy and fluorescence characteristics indicated outstanding results from this investigationConclusions:Various pharmacognostical and physico-chemical parameters have pivotal roles in identification, authentication and establishment of quality parameters of the species.