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1.
Molecules ; 29(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38398517

RESUMO

Obesity is a source of significant pathologies and deadly diseases, including heart disease, diabetes, and cancer. One of the most intriguing strategies in the hunt for new anti-obesity medications is the inhibition of pancreatic lipase (PL). This study presents a novel application of short α and ß-mixed peptides as pancreatic lipase inhibitors. These peptides were synthesized in the solution phase and characterized using FTIR and 1H-NMR. L-proline is present in a high percentage of natural anti-lipase peptides and was used as a ß-amino acid in this study to enhance anti-lipase activity and proteolytic stability. Moreover, L-α-proline was converted to ß-amino acid derivatives using the Arndt-Eistert method with the advantage of stereo control at the α-carbon. The synthesized peptides with anti-lipase activity are N-Boc-ß-Pro-Gly-OBz (93%), N-Boc-O-Bz-Tyr-ß-Pro-ß-Pro-Gly-OBz (92%), N-Boc-O-Bz-Tyr-ß-Pro-COOH (91%), N-Boc-Phe-ß-Pro-OCH3 (90%), and N-Boc-O-Bz-Tyr-ß-Pro-OCH3 (89%). These peptides may function as lead molecules for further modification to more significant molecules, which can help control obesity.


Assuntos
Peptídeos , Prolina , Humanos , Peptídeos/farmacologia , Peptídeos/química , Aminoácidos , Lipase , Obesidade
2.
Chem Asian J ; : e202301051, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216532

RESUMO

Enhanced electrocatalysts that are cost-effective, durable, and derived from abundant resources are imperative for developing efficient and sustainable electrochemical water-splitting systems to produce hydrogen. Therefore, the design and development of non-noble-based catalysts with more environmentally sustainable alternatives in efficient alkaline electrolyzers are important. This work reports ferrocene (Fc)-incorporated nickel sulfide nanostructured electrocatalysts (Fc-NiS) using a one-step facile solvothermal method for water-splitting reactions. Fc-NiS exhibited exceptional electrocatalytic activity under highly alkaline conditions, evident from its peak current density of 345 mA cm-2 , surpassing the 153 mA cm-2 achieved by the pristine nickel sulfide (NiS) catalysts. Introducing ferrocene enhances electrical conductivity and facilitates charge transfer during water-splitting reactions, owing to the inclusion of iron metal. Fc-NiS exhibits a very small overpotential of 290 mV at 10 mA cm-2 and a Tafel slope of 50.46 mV dec-1 , indicating its superior charge transfer characteristics for the three-electron transfer process involved in water splitting. This outstanding electrocatalytic performance is due to the synergistic effects embedded within the nanoscale architecture of Fc-NiS. Furthermore, the Fc-NiS catalyst also shows a stable response for the water-splitting reactions. It maintains a steady current density with an 87% retention rate for 25 hours of continuous operation, indicating its robustness and potential for prolonged electrolysis processes.

3.
Faraday Discuss ; 246(0): 11-46, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37395363

RESUMO

In many practical applications, ions are the primary charge carrier and must move through either semipermeable membranes or through pores, which mimic ion channels in biological systems. In analogy to electronic devices, the "iontronic" ones use electric fields to induce the charge motion. However, unlike the electrons that move through a conductor, motion of ions is usually associated with simultaneous solvent flow. A study of electroosmotic flow through narrow pores is an outstanding challenge that lies at the interface of non-equilibrium statistical mechanics and fluid dynamics. In this paper, we will review recent works that use dissipative particle dynamics simulations to tackle this difficult problem. We will also present a classical density functional theory (DFT) based on the hypernetted-chain approximation (HNC), which allows us to calculate the velocity of electroosmotic flows inside nanopores containing 1 : 1 or 2 : 1 electrolyte solution. The theoretical results will be compared with simulations. In simulations, the electrostatic interactions are treated using the recently introduced pseudo-1D Ewald summation method. The zeta potentials calculated from the location of the shear plane of a pure solvent are found to agree reasonably well with the Smoluchowski equation. However, the quantitative structure of the fluid velocity profiles deviates significantly from the predictions of the Smoluchowski equation in the case of charged pores with 2 : 1 electrolyte. For low to moderate surface charge densities, the DFT allows us to accurately calculate the electrostatic potential profiles and the zeta potentials inside the nanopores. For pores with 1 : 1 electrolyte, the agreement between theory and simulation is particularly good for large ions, for which steric effects dominate over the ionic electrostatic correlations. The electroosmotic flow is found to depend very strongly on the ionic radii. In the case of pores containing 2 : 1 electrolyte, we observe a reentrant transition in which the electroosmotic flow first reverses and then returns to normal as the surface change density of the pore is increased.

4.
Plants (Basel) ; 12(13)2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37447099

RESUMO

Nomenclatural types for twenty-nine names belonging to the genus Asparagus are typified and discussed. The following names are lectotypified: A. altiscandens Engl. & Gilg, A. altissimus Munby, A. baumii Engl. & Gilg, A. benguellensis Baker, A. burchellii Baker, A. curillus Buch.-Ham. ex Roxb., A. deflexus Baker, A. duchesnei L.Linden, A. equisetoides Welw. ex Baker, A. fasciculatus Thunb., A. griffithii, Baker, A. homblei De Wild., A. kaessneri De Wild., A. lecardii De Wild., A. longicladus N.E.Br., A. longiflorus Franch., A. monophyllus Baker, A. palaestinus Baker, A. pastorianus Webb & Berthel., A. persicus Baker, A. poissonii H.Perrier, A. psilurus Welw. ex Baker, A. ritschardii De Wild., A. sapinii De Wild., A. scandens Thunb., A. schumanianus Schltr. ex H.Perrier, A. stellatus Baker, A. subfalcatus De Wild., and A. undulatus (L.f.) Thunb. (synonym of Dracaena undulata L.f.). A new name, Asparagus neofasciculatus, is proposed as a replacement name for A. fasciculatus Thunb., which is an illegitimate later homonym of A. fasciculatus R.Br. The original protologue of these names and the original materials are evaluated. Nomenclature remarks discussing the selection of type specimens are given for each name, and known isotypes or isolectotypes are also cited. This information could be utilized as a reference for future taxonomic and systematic studies on Asparagus around the world.

5.
Artigo em Inglês | MEDLINE | ID: mdl-37504956

RESUMO

The developed article considers SIR problems for the recent COVID-19 pandemic, in which each component is divided into two subgroups: young and adults. These subgroups are distributed among two classes in each compartment, and the effect of COVID-19 is observed in each class. The fractional problem is investigated using the non-singular operator of Atangana Baleanu in the Caputo sense (ABC). The existence and uniqueness of the solution are calculated using the fundamental theorems of fixed point theory. The stability development is also determined using the Ulam-Hyers stability technique. The approximate solution is evaluated using the fractional Adams-Bashforth technique, providing a wide range of choices for selecting fractional order parameters. The simulation is plotted against available data to verify the obtained scheme. Different fractional-order approximations are compared to integer-order curves of various orders. Therefore, this analysis represents the recent COVID-19 pandemic, differentiated by age at different fractional orders. The analysis reveals the impact of COVID-19 on young and adult populations. Adults, who typically have weaker immune systems, are more susceptible to infection compared to young people. Similarly, recovery from infection is higher among young infected individuals compared to infected cases in adults.

6.
Environ Sci Pollut Res Int ; 30(60): 124992-125005, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37498427

RESUMO

Graphene quantum dots (GQDs), a new solid-state electron transfer material was anchored to nitrogen-doped TiO2 via sol gel method. The introduction of GQDs effectively extended light absorption of TiO2 from UV to visible region. GQD-N-TiO2 demonstrated lower PL intensity at excitation wavelengths of 320 to 450 nm confirming enhanced exciton lifespan. GQD-N-TiO2-300 revealed higher surface area (191.91m2 g-1), pore diameter (1.94 nm), TEM particle size distribution (4.88 ± 1.26 nm) with lattice spacing of 0.45 nm and bandgap (2.91 eV). In addition, GQDs incorporation shifted XPS spectrum of Ti 2p to lower binding energy level (458.36 eV), while substitution of oxygen sites in TiO2 lattice by carbon were confirmed through deconvolution of C 1 s spectrum. Photocatalytic reaction followed the pseudo first order reaction and continuous reductions in apparent rate constant (Kapp) with incremental increase in RB5 concentration. Langmuir-Hinshelwood model showed surface reaction rate constants KC = 1.95 mg L-1 min-1 and KLH = 0.76 L mg-1. The active species trapping, and mechanism studies indicated the photocatalytic decolorization of RB5 through GQD-N-TiO2 was governed by type II heterojunction. Overall, the photodecolorization reactions were triggered by the formation of holes and reactive oxygen species. The presence of •OH, 1O2, and O2• during the photocatalytic process were confirmed through EPR analysis. The excellent photocatalytic decolorization of the synthesized nanocomposite against RB5 can be ascribed to the presence of GQDs in the TiO2 lattice that acted as excellent electron transporter and photosensitizer. This study provides a basis for using nonmetal, abundant, and benign materials like graphene quantum dots to enhance the TiO2 photocatalytic efficiency, opening new possibilities for environmental applications.


Assuntos
Grafite , Pontos Quânticos , Luz , Nitrogênio
7.
J Chem Phys ; 158(14): 144902, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37061472

RESUMO

In this work, we perform molecular dynamics simulations to study a spherical polyelectrolyte brush. We explore the effects of surface polarization and electrostatic coupling on brush size and distribution of counterions. The method of image charges is considered to take into account surface polarization, considering a metallic, an unpolarizable, and a dielectric nano-core. It is observed that, for all cases, a moderate shrinking-swelling effect appears with an increase in the electrostatic coupling parameter. This effect occurs under high Manning ratios. The curves relating the average size of polyelectrolyte brush as a function of coupling show a minimum. The results show that the grafting density of polyelectrolytes on the nano-core surface plays an important role in the polarization effect. We consider a modified Poisson-Boltzmann theory to describe the counterion profiles around the brush in the case of unpolarizable nano-cores and weak electrostatic coupling.

8.
Plants (Basel) ; 12(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36616342

RESUMO

Phaseolus vulgaris L. is the major pulse cultivated and culturally inculcated in the food habits of the locals in the Himalayan mountainous region of Azad Jammu and Kashmir (AJK), Pakistan. The current study was designed to investigate the role of P. vulgaris cultivation in providing livelihood support and to evaluate its production and consumption patterns correlated with the household variables in the state of AJK. The socio-economic data was collected from nine bean cultivated areas in six districts of AJK. The data was acquired by administrating a total of 522 detailed semi structured questionnaires from a diverse array of the respondents following the snowball technique focusing on yield, consumption, revenue generation and livelihood support provided by bean cultivation. The results revealed that common bean cultivation provided significant livelihood support to the local mountainous populations with an average annual income of 50.80 $/family. Subsequently, bean production contributed an average annual per capita income of 6.81 $ in the area, which was attributed to the large family size. Local populations showed an average bean production of 33.93 kg/family, whereas the average annual bean consumption was recorded as 31.99 kg/family in the region. Bean crops were recorded to have an average price of $1.49/kg, with significant variations in the study area correlated with local yield. A data analysis indicated a strong correlation in bean production and consumption patterns. Common bean farmers had a very small farm size, averaging 0.24 ha, where 100% of farmers cultivated common beans as an intercrop with Maize as the primary crop. A Pearson's test (p value < 0.05) revealed significant correlations between land holding and bean production as well as consumption, and bean production with annual per capita income. Small farm size, declining soil fertility, low bean pricing and the unavailability of market mechanisms were identified as the major challenges faced by the common bean farmers. It is recommended to employ an integrated bean farming approach to enhance the economic impact of common bean cultivation in the socioeconomic appraisal of the local populations.

9.
Comput Methods Biomech Biomed Engin ; 26(1): 98-112, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35271386

RESUMO

In the given manuscript, the fractional mathematical model for the current pandemic of COVID-19 is investigated. The model is composed of four agents of susceptible (S), infectious (I), quarantined (Q) and recovered (R) cases respectively. The fractional operator of Atangana-Baleanu-Caputo (ABC) is applied to the considered model for the fractional dynamics. The basic reproduction number is computed for the stability analysis. The techniques of existence and uniqueness of the solution are established with the help of fixed point theory. The concept of stability is also derived using the Ulam-Hyers stability technique. With the help of the fractional order numerical method of Adams-Bashforth, we find the approximate solution of the said model. The obtained scheme is simulated on different fractional orders along with the comparison of integer orders. Varying the numerical values for the contact rate ζ, different simulations are performed to check the effect of it on the dynamics of COVID-19.

10.
Med Biol Eng Comput ; 60(11): 3169-3185, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36107356

RESUMO

This manuscript is devoted to investigate the mathematical model of fractional-order dynamical system of the recent disease caused by Corona virus. The said disease is known as Corona virus infectious disease (COVID-19). Here we analyze the modified SEIR pandemic fractional order model under nonsingular kernel type derivative introduced by Atangana, Baleanu and Caputo ([Formula: see text]) to investigate the transmission dynamics. For the validity of the proposed model, we establish some qualitative results about existence and uniqueness of solution by using fixed point approach. Further for numerical interpretation and simulations, we utilize Adams-Bashforth method. For numerical investigations, we use some available clinical data of the Wuhan city of China, where the infection initially had been identified. The disease free and pandemic equilibrium points are computed to verify the stability analysis. Also we testify the proposed model through the available data of Pakistan. We also compare the simulated data with the reported real data to demonstrate validity of the numerical scheme and our analysis.


Assuntos
COVID-19 , Dinâmica não Linear , Humanos , Modelos Teóricos
12.
Microsc Res Tech ; 85(7): 2409-2427, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35302261

RESUMO

Palynological characterization is considered to be one of the significant taxonomic tools for the delimitation and identification of morphologically complicated taxa. Hence, the pollen morphology of 12 species of spineless Astragalus L. was examined using light and scanning electron microscopy. Studied pollen were small to medium, monad, prolate to per-prolate and tricolporate type in all studied taxa. The exine sculpturing varied from reticulate to microreticulate whereas colpus ornamentation ranged from scabrate to granulate. Furthermore, maximum polar and equatorial diameter was recorded in Astragalus leucocephalus Bunge. (45.00 µm) and A. pyrrhotrichus Boiss. (22.91 µm) while minimum in A. amherstianus Benth. ex Royle (28.75 µm) and A. amherstianus Benth. ex Royle (15.00 µm), respectively. Similarly, the ratio of polar to equatorial diameter was recorded maximum in A. ophiocarpus Boiss. (2.05). The width of colpi was larger in A. hamosus L. (1.29 µm) and smaller in A. ophiocarpus Boiss. (0.62 µm). We have also found the maximum value of mesocolpium in A. retamocarpus Boiss. (2.08 µm) while minimum in A. oxyglottis Steven ex M.Bieb. (1.87 µm). The quantitative pollen attributes helped in the development of pollen keys for the accurate and quick identification of the studied species. Furthermore, ordination and cluster analysis were performed for the differentiation of the investigated taxa at species level. Based on our results, we conclude that pollen features can be used for the delimitation and identification of the studied taxa. RESEARCH HIGHLIGHTS: Pollen micromorphology is a useful tool for classifying complicated taxa. The pollen micromorphology of 12 spineless species of Astragalus L. was studied using LM and SEM. The observed pollen characteristics aided in Astragalus L. serve for the identification and classification of taxa at specific level.


Assuntos
Fabaceae , Fosmet , Elétrons , Microscopia Eletrônica de Varredura , Pólen/ultraestrutura
13.
Front Plant Sci ; 13: 850567, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35251114

RESUMO

It has been established that wheat (Triticum aestivum L.) has a higher Cd absorption capacity than other cereal crops causing an excess daily Cd intake and a huge threat for public health. Therefore, the reduction of Cd accumulation in wheat from the soil is a crucial food-security issue. A pot trial was performed on Cd-stressed wheat seedlings to evaluate the morphological and physio-biochemical responses via foliage spray of two different bio-stimulants, i.e., ascorbic acid (AsA) and moringa leaf extract (MLE). Two wheat cultivars (Fsd-08 and Glxy-13) were exposed to cadmium (CdCl2.5H2O) stress (0, 500, and 1,000 µM), along with foliar spray of AsA (0 and 50 mM) and MLE (0 and 3%). The most observable growth reduction was documented in plants that are exposed to a higher Cd concentration (1,000 µM), followed by the lower Cd level (500 µM). The wheat growth attributes, such as number of leaves per plant, number of tillers per plant, biomass yield, shoot/root length, and leaf area, were greatly depressed under the Cd stress, irrespective of the cultivar. Under the increasing Cd stress, a significant diminution was observed in maximum photochemical efficiency (Fv/Fm), photochemical quenching (qP), and electron transport rate (ETR) accompanied with reduced gas exchange attributes. However, Cd-induced phytotoxicity enhanced the non-photochemical quenching (NPQ) and internal carbon dioxide concentration (Ci), which was confirmed by their significant positive correlation with Cd contents in shoot and root tissues of both cultivars. The contents of proline, AsA, glycine betaine (GB), tocopherol, total free amino acid (TFAA), and total soluble sugar (TSS) were greatly decreased with Cd stress (1,000 µM), while MLE and AsA significantly enhanced the osmolytes accumulation under both Cd levels (especially 500 µM level). The Cd accumulation was predominantly found in the root as compared to shoots in both cultivars, which has declined after the application of MLE and AsA. Conclusively, MLE was found to be more effective to mitigate Cd-induced phytotoxicity up to 500 µM Cd concentration, compared with the AsA amendment.

14.
Environ Sci Pollut Res Int ; 29(32): 48869-48879, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35199269

RESUMO

Exploring extractable phytochemicals from locally adapted sisal plant vegetation vary seasonally at different locations. This study elaborated proximate composition and phytochemical heterogeneity in sisal due to varying environmental conditions analyzed from five districts, i.e., Chakwal, Khushab, Rawalpindi, Faisalabad, and Layyah in Punjab, Pakistan. Extensive surveying and plant sampling across 2 years 2017-2018 and 2018-2019, during mid-spring, summer, autumn, and winter seasons were carried out for understanding the seasonal impact on sisal. The present study was designed in a randomized complete block design (RCBD) and analyzed considering seasonal, yearly, and locational impact. The spatial differences in phytochemicals concentration were strongly associated with environmental conditions prevailing in different seasons. Autumn season reflected saponins, tannins, and flavonoids in higher concentrations during 2018-2019 while steroids and terpenoids were higher during spring 2018-2019. Spatio-temporal variations in the proximate analysis were more apparent in different samples collected from different districts. Data recorded for the Khushab district and autumn season reflected the higher composition of a proximate analysis and phytochemical contents as compared to other seasons. Overall, the spatial differences in phytochemicals concentration were strongly associated with soils and environmental conditions prevailing in different seasons in selected districts.


Assuntos
Agave , Agave/química , Paquistão , Compostos Fitoquímicos , Estações do Ano , Solo
15.
Microsc Res Tech ; 85(5): 1671-1684, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34913535

RESUMO

Biodiesel is a promising, bio-based, renewable, nontoxic, environment friendly, and alternative fuel for petroleum derived fuels which helps to reduce dependency on conventional fossil fuels. In this study, six novel, nonedible seed oil producing feedstock were explored for their potential for sustainable production of biodiesel. It is very important to correctly identify oil yielding plant species. Scanning electron microscopy (SEM) was used as reliable tool for authentic identification of oil yielding seeds. Macromorphological characters of seeds were studied with light microscopy (LM). Outcomes of LM of seeds exposed distinctive variation in seed size from 16.3 to 3.2 mm in length and 12.4 to 0.9 mm in width, shape varied from oval to triangular, and color from black to light brown. Oil content of nonedible seed ranged from 25 to 30% (w/w). Free fatty acid content of seed oil varied from 0.32 to 2.5 mg KOH/g. Moreover, ultra structural study of seeds via SEM showed variation in surface sculpturing, cell arrangement, cell shape, periclinal wall shape, margins, protuberances, and anticlinal wall shape. Surface sculpturing varied from rugged, reticulate, varrucose, papillate, and striate. Periclinal wall arrangements confirmed variation from rough, wavy, raised, depressed, smooth, and elevated whereas, anticlinal walls pattern showed variation from profuse undulating, smooth, raised, grooved, deep, curved, and depressed. It was concluded that SEM could be a latent and advanced technique in unveiling hidden micromorphological characters of nonedible oil yielding seeds which delivers valuable information to researchers and indigenous people for precise and authentic identification and recognition.


Assuntos
Biocombustíveis , Sementes , Humanos , Microscopia Eletrônica de Varredura , Óleos de Plantas , Sementes/anatomia & histologia
16.
Urol Case Rep ; 40: 101946, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34840959

RESUMO

Priapism is defined as a whole or partial penile erection that persists for more than 4 hours without stimulation. Hematologic disorders are a significant risk factor for ischemic priapism. Here, we report a case of priapism due to chronic myelocytic leukemia. This is rare considering that the epidemiology of priapism in hematologic malignancies includes only 1% of patients with chronic myelocytic leukemia. Priapism has a relatively high complication rate, and management generally focuses on prompt treatment. Hematologic screening should be performed to rule out the possibility of these disorders that could underlie priapism.

17.
Microsc Res Tech ; 85(2): 591-606, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34534384

RESUMO

Petiole anatomy of 15 species of family Asteraceae was examined which aimed to investigate petiolar anatomical structures for species level identification. Shandon Microtome was used for petiole histological preparations. Both qualitative and quantitative features were studied under microscope which showed significant variation in petiole, collenchyma, parenchyma shape/size, vascular bundles arrangement/size, and vessel elements quantity. Artemisia japonica Thunb., Cirsium vulgare (Savi) Ten., Myriactis nepalensis Less., Seriphidium brevifolium Ling & Y.R.Ling, Taraxacum officinale (L.) Weber ex F.H.Wigg., and Xanthium strumarium L. showed winged petioles. Maximum length and width of upper and lower epidermis was found in Tagetes erecta L. which is 23.05 ± 0.89 µm, 24.9 ± 1.257 µm length and 21.75 ± 1.38067 µm, 22.75 ± 0.467 µm width, respectively. Petioles of Parthenium hysterophorus L. was longest one with 9.85 ± 10.45 µm while A. japonica Thunb. showed highest number of vessel elements. Maximum size of vascular bundles was found in T. erecta L. with 5.05 ± 14.25 µm. Artemisia annua L., C. vulgare (Savi) Ten, Cyanthillium cinereum (L.) H.Rob., Helianthus annus L., M. nepalensis Less., P. hysterophorus L., Senecio chrysanthemoides DC. have trichomes while Tussilago farfara L. has highest number of vascular bundles. All species have angular collenchyma type except M. nepalensis Less., P. hysterophorus L., S. brevifolium Ling & Y.R.Ling, Tagetes minuta L., T. officinale L., S. chrysanthemoides DC., and T. farfara L. Cluster analysis implemented that distinct plant species in cluster. Petiolar anatomical structures and taxonomic key will helpful for distinguishing Asteraceous taxa at genus and species level. This taxonomic significant investigation will also provide baseline to taxonomists for other Asteraceae studies and phylogenetic research.


Assuntos
Asteraceae , Tricomas , Microscopia Eletrônica de Varredura , Paquistão , Filogenia , Folhas de Planta
18.
Biomolecules ; 11(7)2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34356629

RESUMO

Soil salinity is the major limiting factor restricting plant growth and development. Little is known about the comparative and combined effects of gibberellic acid (GA3) seed priming and foliar application on maize under salt stress. The current study determined the impact of different application methods of GA3 on morpho-physiological, biochemical and molecular responses of maize seedlings under three salinity stress treatments (no salinity, moderate salinity-6 dS m-1, and severe salinity-12 dS m-1). The GA3 treatments consisted of control, hydro-priming (HP), water foliar spray (WFS), HP + WFS, seed priming with GA3 (GA3P, 100 mg L-1), foliar spray with GA3 (GA3FS, 100ppm) and GA3P + GA3FS. Salt stress particularly at 12 dS m-1 reduced the length of shoots and roots, fresh and dry weights, chlorophyll, and carotenoid contents, K+ ion accumulation and activities of antioxidant enzymes, while enhanced the oxidative damage and accumulation of the Na+ ion in maize plants. Nevertheless, the application of GA3 improved maize growth, reduced oxidative stress, and increased the antioxidant enzymes activities, antioxidant genes expression, and K+ ion concentration under salt stress. Compared with control, the GA3P + GA3FS recorded the highest increase in roots and shoots length (19-37%), roots fresh and dry weights (31-43%), shoots fresh and dry weights (31-47%), chlorophyll content (21-70%), antioxidant enzymes activities (73.03-150.74%), total soluble protein (13.05%), K+ concentration (13-23%) and antioxidants genes expression levels under different salinity levels. This treatment also reduced the H2O2 content, and Na+ ion concentration. These results indicated that GA3P + GA3FS could be used as an effective tool for improving the maize growth and development, and reducing the oxidative stress in salt-contaminated soils.


Assuntos
Antioxidantes/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Giberelinas/farmacologia , Tolerância ao Sal/efeitos dos fármacos , Zea mays , Tolerância ao Sal/genética , Zea mays/genética , Zea mays/crescimento & desenvolvimento
19.
Microsc Res Tech ; 84(12): 2988-2999, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34250676

RESUMO

Date palm (Phoenix dactylifera L.) is an important traditional crop having socioeconomic values. To best of literature review and our knowledge, there is a gap of taxonomic study on the role of morpho-anatomical features of date palm for correct identification of its varieties. With the advancement in the field of microscopy, anatomical features are considered very effective taxonomical markers. The present study was aimed to analyze the taxonomic variations using leaf epidermal anatomy and to highlight the importance of leaf epidermis to resolve identification ambiguities among the different varieties of date palms. The study includes analysis of leaf epidermal anatomy of 18 different commercial varieties of date palm collected from different areas of Pakistan. A diverse range of shape and size of epidermal cells, subsidiary cells, guard cells, stomata, stomatal pore was observed on abaxial as well as adaxial among studied date palm varieties via LM and found to be very helpful tool in discrimination of varieties. The shape of epidermal cells on both abaxial and adaxial surfaces varies including elongated, irregular, polygonal, curved, and spherical or sometime mixed of these. The values of stomatal indices on both surfaces showed wide variations.


Assuntos
Phoeniceae , Epiderme Vegetal , Microscopia Eletrônica de Varredura , Folhas de Planta , Estômatos de Plantas , Tricomas
20.
Saudi J Biol Sci ; 28(5): 2655-2666, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34025150

RESUMO

Salinity is extremely hazardous to agriculture worldwide and its expanding constantly. Soil of almost 100 countries facing salinity problem including Pakistan. Cyperus laevigatus also act as salinity indicator species is a naturally adapted halophyte dispersed in subtropical regions of world. Six populations of C. laevigatus were collected from different saline habitats to evaluate adaptations regarding anatomical and physiological characteristics. C. laevigatus is perfectly adapted to harsh environmental conditions like dry barren soils, saline lakes, hyper-saline wetlands and salt marshes. Ecological success of this species is due to plasticity in physiological and anatomical characteristics to adapt variable environmental conditions. C. laevigatus is a halophyte, exhibited increased biomass production in moderately saline habitat. Higher uptake of K+ occurs to compensate the uptake of Na+ ion contents, a striking feature of salt-tolerant and halophytic species. Accumulation of osmoprotectants like proline, free amino acids, soluble sugar and protein contribute significantly to osmotic adjustment. Stem thickness enhanced as salinity level of habitat increased to store water in parenchymatous tissues under physiological drought. Intensive sclerification in root cortex provide mechanical strength to plant as well as prevent the radial leakage of water. Well-developed aerenchyma, increased vascular bundle area, broader vessels, small and dense stomata are critical to cope with environmental hazards. Population of Jahlar lake showing maximum biomass production indicate that this species grows better in moderate salinities. Therefore, this species will prove very useful for revegetation of salt affected rangeland and prairies by direct growth of such halophytic ecotypes.

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