b) 2023-Scopus Open Access (Pdf)

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NBCL5 FUNCTIONALIZED PERLITE: A POTENT AND RECYCLABLE CATALYST FOR SYNTHESIS OF PYRANS (Article)
(MDPI, 2023-02) Lakshminarayanan, Komalavalli; Sivanandhan, Monisha; Ramasundaram, Subramaniyan; Oh, Tae Hwan; Shah, Kinjal J; Saranraj, Kumaravel; Parasuraman, Amutha; Balu, Krishnakumar
Niobium pentachloride functionalised perlite was prepared via a solid state dispersion technique, which was utilized as an efficient heterogeneous catalyst for the synthesis of pyrans. The immobilisation of NbCl5 over perlite was examined by Fourier-transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), Thermogravimetric analysis (TGA), scanning electron microscope (SEM) with energy dispersive spectra (EDS), and Brunauer, Emmett and Teller (BET) surface area measurements. The wt% of NbCl5-loaded perlite was optimized based on the adequacy with respect to the yield of the pyrans in various solvents. The recyclability of the catalyst was validated in synthesizing pyrans and the results marked its efficiency up to five runs. The efficacy of the NbCl5/perlite catalyst was found to be comparable and better with respect to the other heterogeneous catalysts reported. The structures of pyrans were confirmed by FT-IR, 1H and 13C NMR spectral techniques. The proposed recyclable heterogeneous NbCl5/perlite catalyst simplifies the protocol, and has minimal chemical waste, a lower reaction time and a high-yield.
PESTICIDE RECOMMENDATION FOR DIFFERENT LEAF DISEASES AND RELATED PESTS USING MULTI-DIMENSIONAL FEATURE LEARNING DEEP CLASSIFIER (Article)
(International Information and Engineering Technology Association, 2023-02) Saleem, Jaithoon Bibi Mohammed; Shanmugam, Karpagavalli
In agricultural applications, the most essential task is to classify leaf diseases and their associated pests from various aspects. To achieve this, a Deep Convolutional Neural Network (DCNN) model was developed to classify the leaf diseases based on the soil and climatic features. But it needs a recommendation system to control the pesticide use for controlling the leaf diseases caused by specific pests. Hence, this paper hybridizes the Multi-dimensional Feature Learning-based DCNN (MFL-DCNN) with the Rough Set (RS) on an intuitionistic Fuzzy approximation space (RSF)-based decision support system to suggest the proper pesticides for a certain crop to be planted in a particular region. First, the leaf images are augmented by the Positional-aware Dual-Attention and Topology-Fusion with Evolutionary Generative Adversarial Network (PDATFEGAN) model. Then, the multi-dimensional data such as the created leaf images, pest, soil, weather, and pesticide data are fed to the DCNN with a softmax classifier for classifying leaf diseases and related pests. Then, the RSF-based decision model is applied, which determines the correlation between leaf disease and pests to recommend suitable pesticides. Finally, the experimental results reveal that the MFL-DCNN-RSF accomplishes a maximum efficiency than all other models for recommending pesticides to control leaf diseases and pests.
BIOSYNTHESIS AND BIODEGRADATION OF POLY(3-HYDROXYBUTYRATE) FROM PRIESTIA FLEXA; A PROMISING MANGROVE HALOPHYTE TOWARDS THE DEVELOPMENT OF SUSTAINABLE ECO-FRIENDLY BIOPLASTICS (Article)
(Elsevier GmbH, 2023-02) Chathalingath, Nayana; Kingsly, Joshua Stephen; Gunasekar, Anbarasi
The protracted persistence of petrochemical plastics in the environment and their non-biodegradability impede the survival of living creatures. Recently, biopolymers are being thoroughly researched as a potential replacement for conventional plastics. This present study sought to locate Poly(3-hydroxybutyrate) synthesizing bacterial species prevalent in the mangrove ecosystem. Six halophilic bacterial isolates were obtained from the mangrove habitat, four isolates displayed superior cell dry weight as well as PHB accumulation. Isolate PMPHB5 showed the highest cell dry weight (4.92 ± 0.02 g/L), while the maximum PHA yield (80%) was found with PMPHB7. Hence, PMPHB7 was chosen for further optimization of carbon source wherein glucose demonstrated improved cell growth as well as PHB production. The characterization of the PHB granules was performed by FT-IR spectroscopy and FE-SEM EDX. The presence of characteristic elements in the sample was confirmed using EDX. Isolate PMPHB7 was further identified as Priestia flexa through 16S rRNA gene sequencing (GenBank accession number: ON362236) and a phylogenetic tree was constructed to reveal the molecular relationships of this organism with others. The solvent-cast biopolymer film was made to check the biodegradability of the extracted PHB. When buried in soil, it was found that the biopolymer film exhibited approximately 73% biodegradation after 21 days. Thus, the present study sheds light on the potential of mangrove-associated halophytes to efficiently produce PHB that is readily biodegradable in soil.
PLANT DERIVED EXOSOME- LIKE NANOVESICLES: AN UPDATED OVERVIEW (Review)
(Elsevier B.V, 2023-02) Subha, D; Harshnii, K; Madhikiruba, K G; Nandhini, M; Tamilselvi, K S
Exosomes are nanovesicles in the size range of 30–150 nm, produced by mammalian and plant cells. They have the lipid bilayer enclosing a unique mix of biologically active components including proteins, nucleic acids, metabolites and lipids, that depend on their source of origin. The plant derived nanovesicles are gaining considerable research attention due to their ability to be absorbed from the dietary sources. Their bioactive components impart many therapeutic properties to them such as anti-tumorigenic, anti-oxidative, anti-inflammatory, hepatoprotective effects and tissue regeneration. The possibilities of using plant derived exosomes for drug delivery is also promising. This review focusses on the biogenesis and biological nature of exosomes derived from plants and describes their various inherent therapeutic properties. It sheds light on the recently developed methods to study them. The existing challenges in the exosomal research as well as the future prospective are highlighted. Overall, it is an update on the advancements on the research in plant exosomes which can provide a replacement for toxic synthetic drugs and possibilities for disease therapy.
AN AMINO ACID GRAFTED GRAPHENE OXIDE AS PROMISING MATERIAL IN POLY(UREA-FORMALDEHYDE)-EPOXY MICROCAPSULES FOR ENHANCING THE INTERFACIAL ADHESION OF EPOXY COATINGS (Article)
(Asian Publication Corporation, 2023-03) Priyanka, D; Nalini, D
Novel microencapsulated materials with superior anti-corrosion properties and improved adhesive strength on the metal substrate were produced by emulsion polymerization and characterized successfully. Initially, serine grafted graphene oxide was prepared and characterized through various sophisticated techniques. Then, MC-GO/epoxy and MC-GO-Ser were individually impregnated into th epoxy system and applied on the mild steel substrates. Corrosion tests were performed to evaluate the non-corrosive nature of MC-GO/epoxy and MC-GO-Ser/epoxy samples. After 7 days of exposure in saline media, MC-GO-Ser microcapsules demonstrated 80.6 % protective efficiency. Furthermore, the peel strength of 2.90 N revealed that the coating loaded with MC-GO-Ser microcapsules had improved adherence to the mild steel surface. Results of urea-formaldehyde GO-Ser microcapsules showed better corrosion protection and greater adhesive strength, which is probably because of the exceptional barrier action of microcapsules against the incursion of corrosion solution onto the mild steel surface.
MANNOSE: A POTENTIAL SACCHARIDE CANDIDATE IN DISEASE MANAGEMENT (Review)
(Springer, 2023-03) Dhanalakshmi, M; Sruthi, D; Jinuraj, K R; Das, Kajari; Dave, Sushma; Andal N, Muthulakshmi; Das, Jayashankar
There are a plethora of antibiotic resistance cases and humans are marching towards another big survival test of evolution along with drastic climate change and infectious diseases. Ever since the first antibiotic [penicillin], and the myriad of vaccines, we were privileged to escape many infectious disease threats. The survival technique of pathogens seems rapidly changing and sometimes mimicking our own systems in such a perfect manner that we are left unarmed against them. Apart from searching for natural alternatives, repurposing existing drugs more effectively is becoming a familiar approach to new therapeutic opportunities. The ingenious use of revolutionary artificial intelligence-enabled drug discovery techniques is coping with the speed of such alterations. D-Mannose is a great hope as a nutraceutical in drug discovery, against CDG, diabetes, obesity, lung disease, and autoimmune diseases and recent findings of anti-tumor activity make it interesting along with its role in drug delivery enhancing techniques. A very unique work done in the present investigation is the collection of data from the ChEMBL database and presenting the targetable proteins on pathogens as well as on humans. It shows Mannose has 50 targets and the majority of them are on human beings. The structure and conformation of certain monosaccharides have a decisive role in receptor pathogen interactions and here we attempt to review the multifaceted roles of Mannose sugar, its targets associated with different diseases, as a natural molecule having many success stories as a drug and future hope for disease management.
GENERATING NOVEL FOCAL PATTERNS FOR RADIAL VARIANT VECTOR BEAM FOCUSING THROUGH A DIELECTRIC INTERFACE
(Photonics Society of Poland, 2023-04-02) Maruthasalam, Lavanya; Thiruarul, Duraisamy; Rajesh, Karuppaiya Balasundaram
Electric and magnetic energy densities as well as energy flux (Poynting vector) for radial variant vector beam focusing through a dielectric interface is analyzed numerically based on vector diffraction theory. The electric and magnetic energy densities are tailored by properly manipulating the radial as well as initial phases to generates novel focal patterns in the focal area. These peculiar properties may find applications in fields such as optical trapping, optical recording, magnetic recording, and magnetic resonance microscopy and semiconductor inspection.
GREEN NANOBIOPOLYMERS FOR ECOLOGICAL APPLICATIONS: A STEP TOWARDS A SUSTAINABLE ENVIRONMENT (Review)
(Royal Society of Chemistry, 2023-04-20) Chincholikar, Preeti; Singh, Kshitij RB; Natarajan, Arunadevi; Kerry, Rout George; Singh, Jay; Malviya, Jitendra; Singh, Ravindra Pratap
To minimize the usage of non-renewable resources and to maintain a sustainable environment, the exploitation of green nanobiopolymers should be enhanced. Biopolymers are generally developed from various microorganisms and plants in the specified condition. This review article discusses the current advances and trends of biopolymers, particularly in the arena of nanotechnology. In addition, discussion on various synthesis steps and structural characterization of green polymer materials like cellulose, chitin, and lignin is also encompassed. This article aims to coordinate the most recent outputs and possible future utilization of nanobiopolymers to the ecosystem with negligible effects by promoting the utilities of polymeric materials like polycaprolactones, starch, and nanocellulose. Additionally, strategic modification of cellulose into nanocellulose via rearrangement of the polymeric compound to serve various industrial and medical purposes has also been highlighted in the review. Specifically, the process of nanoencapsulation and its advancements in terms of nutritional aspects was also presented. The potential utility of green nanobiopolymers is one of the best cost-effective alternatives concerning circular economy and thereby helps to maintain sustainability.
DOES FINANCIAL DEEPENING FOSTER CLEAN ENERGY SUSTAINABILITY OVER CONVENTIONAL ONES? EXAMINING THE NEXUS BETWEEN FINANCIAL DEEPENING, URBANIZATION, INSTITUTIONAL QUALITY, AND ENERGY CONSUMPTION IN CHINA (Article)
(MDPI, 2023-05) Wang, Yingyi; Qamruzzaman, Md; Serfraz, Ayesha; Theivanayaki, Manickavasagam
Energy availability and the selection of suitable energy sources have substantial implications on both economic and environmental sustainability, and it is because the environmental protection cost is directly linked to overall energy inclusion in the economy. Thus, the importance of clean energy has been noticed in the literature regardless of the economic structure. The purpose of the study is to discover the effects of financial deepening (FD), urbanization (UR), and institutional quality (IQ) on China’s energy consumption. Annual time series date for 1985 to 2019 utilized for documenting the coefficients of explanatory variables by implementing both linear and nonlinear Autoregressive Distributed Lagged (ARDL) and the Fourier-TY causality test. In terms of the test statistics for combined and Maki cointegration, the study revealed that a long-run association prevails in the empirical nexus. Moreover, the symmetric and asymmetric framework established long-run associations. Referring to the coefficients of financial deepening, UR, and governmental effectiveness, the study found a statistically significant and favorable impression of REC. While financial deepening and governmental effectiveness unveiled negatively influenced NREC and fossil energy consumption. The asymmetric linkage between explained and explanatory variables was confirmed through the execution of a standard weld test with a null symmetry. The asymmetry coefficients of FD, UR, and IQ were positive and statistically significant at the 1% level in both the long and short runs. The directional causality revealed feedback hypothesis holds in understanding the causal relationship between explanatory factors and RE usage. The policy recommendations for the future were generated from the research findings.
TARGETING THE ENV SPIKE PROTEIN OF HIV WITH NATURALLY OCCURRING COMPOUNDS: AN IN-SILICO STUDY FOR DRUG DESIGNING (Article)
(Springer, 2023-06) Sreeram, S; Sathishkumar, R; Amritha, P.S
Human Immunodeficiency Virus (HIV) infects human by destroying the immune system. The types of HIV strains HIV-1 and HIV-2, among HIV-1 being more prevalent and considered deadly. Eventually either of the strains leads to disease Acquired Immunodeficiency Syndrome (AIDS). Traditional medicinal plants have a pivotal role in the modern pharmacological process due to their rich composition of secondary metabolites with significant biological activity. Computational tools are gaining momentum as they predict with higher accuracy, robust and provide insight in the interaction of small molecule with the disease target protein. This study was conducted for understanding the interaction mode of Phyto compounds with Env spike proteins of HIV. The compounds are studied for ADME properties and molecular docking using Schrödinger software was performed. From the results, Ethyl gallate was observed with least docking score and higher binding affinity for HIV-ENV protein (4CC8) and Cinnamyl acetate (cis/trans) with HIV-1-ENV protein (6ULC).
AN OPTIMIZED UNCERTAINTY AWARE FINE-TUNED TRANSFER LEARNING FOR COVID-19 DIAGNOSIS FROM MEDICAL IMAGES (Article)
(Intelligent Network and Systems Society, 2023-07) Selvam, Deepika; Murugesan, Rajeswari
: In worldwide, COVID-19 has had a significant influence on patients and healthcare systems. Earlier stage of COVID-19 diagnosis and identification are the primary problems in the current pandemic condition. The identification of COVID-19 in CT and chest-X-ray (CXR) imaging is essential for diagnosis, treatment, and evaluation. However, radiologists face a foreseeable issue when it comes to coping with analytical ambiguity in medical imaging. In that situation, a paradigm based on convolutional neural network (CNN) with transfer learning (TL) and taking uncertainty into account was suggested to identify COVID-19 from CT and CXR scan images. However, this method was less capable to extract more useful and distinct image attributes. By fine-tuning the TL network design, this issue can be resolved. The fine tuning model can only fine tune specific layers associated with various goal objectives. However, one of the primary issues with such a method is the selection of layers. To solve this issue, this research uses an enhanced spider monkey optimization (ESMO) technique to select layers of ResNet architecture. Every population of an initialized spider monkey (SM) selects layer and parameter for fine tuning architecture. The fitness value of each SM is used to find best optimal solutions. Categorical cross-entropy loss (CCEL) is considered as fitness of SM. The fitness value of each SM is employed to determine the highest optimal solutions. Subsequent processes such as the stance update process, the learning and decision phase for the local and global leaders of ESMO algorithms, iteratively search for near optimal solutions until convergence. The proposed method can automatically estimate the various CNN layers, which can then be fine-tuned to extract more significant and discriminative features for efficient COVID-19 identification. Finally, the results reveal that the proposed ESMO-ResNet model on SARS-CoV-2 CT database achieves 91.23% accuracy, which is 21.46%, 20.2%, 12.4%, and 6% higher than the AlexNet, multi-source deep transfer learning (MSDTL), stacked convolutional neural network (S-CNN) and dynamic mutual training (DMT) models, respectively. Similarly, the ESMO-ResNet model on Covi-19 Radiography dataset achieves 90.06% accuracy, which is 21.34%, 20%, 9.7%, and 3.5% higher than AlexNet, MSDTL, S-CNN, and DMT models, respectively.
MICROBIAL DEGRADATION AND TRANSFORMATION OF PPCPS IN AQUATIC ENVIRONMENT: A REVIEW (Article)
(Elsevier Ltd, 2023-08) Narayanan, Mathiyazhagan; Kandasamy, Sabariswaran; Lee, Jintae; Barathi, Selvaraj
The Pharmaceuticals and Personal Care Products (PPCPs) presence at harmful levels has been identified in aquatic ecosystems all over the world. Currently, PPCPs are more common in aquatic regions and have been discovered to be extremely harmful to aquatic creatures. Waste-water treatment facilities are the primary cause of PPCPs pollution in aquatic systems due to their limited treatment as well as the following the release of PPCPs. The degree of PPCPs elimination is primarily determined by the method applied for the remediation. It must be addressed in an eco-friendly manner in order to significantly improve the environmental quality or, at the very least, to prevent the spread as well as effects of toxic pollutants. However, when compared to other methods, environmentally friendly strategies (biological methods) are less expensive and require less energy. Most biological methods under aerobic conditions have been shown to degrade PPCPs effectively. Furthermore, the scientific literature indicates that with the exception of a few extremely hydrophobic substances, biological degradation by microbes is the primary process for the majority of PPCPs compounds. Hence, this review discusses about the optimistic role of microbe concerned in the degradation or transformation of PPCPs into non/less toxic form in the polluted environment. Accordingly, more number of microbial strains has been implicated in the biodegradation/transformation of harmful PPCPs through a process termed as bioremediation and their limitations.
FOCUSING PROPERTIES OF AZIMUTHALLY POLARIZED LORENTZ GAUSS VORTEX BEAM THROUGH A DIELECTRIC INTERFACE (Article)
(Photonics Society of Poland, 2023-09) Saraswathi, R.C; Lavanya, Maruthasalam; Udhayakumar, M; Jaroszewicz, Z
Tight focusing properties of azimuthally polarized Lorentz Gaussian vortex beam through a dielectric interface are numerically studied by vector diffraction theory. The focusing properties, such as spot size, depth of focus, and maximum intensity position, are numerically calculated by properly manipulating the Lorentz parameter with/without annular obstruction values. Thus, using annular obstruction, one can generate a highly confined focal spot of long focal depth when using an azimuthally polarized Lorentz Gaussian vortex beam.
MULTI-OBJECTIVE METAHEURISTIC OPTIMIZATION ALGORITHMS FOR WRAPPER-BASED FEATURE SELECTION: A LITERATURE SURVEY (Article)
(Institute of Advanced Engineering and Science, 2023-10) Gopalakrishnan, Anitha; Vadivel, Vinodhini
In the data mining and machine learning (ML) discipline, feature selection problem is considered among many researchers in the recent times. Feature selection process targets to minimize feature set number and maximize performance accuracy by identifying optimal features. Multiple objectives are considered while identifying the optimal feature hence multi-objective metaheuristic optimization algorithms (MOMOAs) are applied. In this study, literature review is performed MOMOAs-for solving wrapper feature selection problem (WFS). The literature review for solving WFS problem and discuss the challenges faced by the researchers in solving the feature selection problem. The literature review is performed on all relevant studies published in the last 12 years [2009-2022]. A detailed overview of the feature selection preliminaries, MOMOAs-WFS, role of the classifier in feature selection problem are presented. The outcome of this literature review is to highlight the existing works related to WFS problem using MOMOAs. Finally, the research areas for improvement are identified and emphasized for the scientists to survey in the field of MOMOAs.
FIRST REPORT OF PANTOEA ANANATIS CAUSING LEAF BLIGHT DISEASE OF POMEGRANATE IN INDIA (Article)
(John Wiley and Sons Inc, 2023-10) Chathalingath, N; Gunasekar, A
Pomegranate (Punica granatum) is an economically important fruit crop and India ranks first for its cultivation globally (Chathalingath & Gunasekar, 2023). During December 2022, pomegranate in Tamil Nadu, India was found with leaf abnormalities. Diseased leaves showed brown necrotic spots surrounded by yellowish margins and the edges of the leaves were wrinkled (Figure 1). Diseased leaves were collected and surface sterilised with 0.2% sodium hypochlorite, and then the lesion-bearing areas were cut and ground with sterile water. The suspension was spread onto nutrient glucose agar and incubated at 28±2°C for five days (Doddaraju et al., 2019). All the colonies on the medium showed similar morphological features and a single colony was selected and assigned the name PBL5. The isolate was Gram-negative and yellow-pigmented, circular with a glistening morphology, positive for starch hydrolysis, catalase, oxidase and methyl red but negative for citrate utilisation, Voges-Proskauer and casein hydrolysis. The isolate was incapable of producing indole and urease.
CONTROLLABILITY ANALYSIS OF IMPULSIVE MULTI-TERM FRACTIONAL-ORDER STOCHASTIC SYSTEMS INVOLVING STATE-DEPENDENT DELAY (Article)
(Multidisciplinary Digital Publishing Institute (MDPI), 2023-10) Arthi, G; Vaanmathi, M; Ma, Yong-Ki
This study deals with the controllability of multi-term fractional-order stochastic systems with impulsive effects and state-dependent delay that exhibit damping behavior. Based on fractional calculus theory, the Caputo fractional derivative is utilized to analyze the controllability of fractional-order systems. Mittag–Leffler functions and Laplace transform are used to derive the solution set of the problem. Sufficient conditions for the controllability of nonlinear systems are achieved using fixed-point techniques and stochastic theory. Finally, the results stated in the paper are validated using examples.
ORGANIC REMOBILIZATION OF ZINC AND PHOSPHORUS AVAILABILITY TO PLANTS BY APPLICATION OF MINERAL SOLUBILIZING BACTERIA PSEUDOMONAS AERUGINOSA (Article)
(Elsevier Ltd, 2023-11) Sunitha kumari, K; Devi, Padma S.N.; Rajamani, Ranjithkumar; Sinouvassane, Djearamane; Lai-Hock, Tey; Ling Shing, Wong; Saminathan, Kayarohanam; Natarajan, Arumugam; Abdulrahman, I. Almansour; Karthikeyan, Perumal
Incessant utilization of chemical fertilizers leads to the accumulation of minerals in the soil, rendering them unavailable to plants. Unaware of the mineral reserves present in the soil, farming communities employ chemical fertilizers once during each cultivation, a practice that causes elevated levels of insoluble minerals within the soil. The use of biofertilizers on the other hand, reduces the impact of chemical fertilizers through the action of microorganisms in the product, which dissolves minerals and makes them readily available for plant uptake, helping to create a sustainable environment for continuous agricultural production. In the current investigation, a field trial employing Arachis hypogaea L was conducted to evaluate the ability of Pseudomonas aeruginosa to enhance plant growth and development by solubilizing minerals present in the soil (such as zinc and phosphorus). A Randomized Complete Block Design (RCBD) included five different treatments as T1: Un inoculated Control; T2: Seeds treated with a liquid formulation of P. aeruginosa; T3: Seeds treated with a liquid formulation of P. aeruginosa and the soil amended with organic manure (farmyard); T4: Soil amended with organic manure (farmyard) alone; T5: Seeds treated with lignite (solid) based formulation of P. aeruginosa were used for the study. Efficacy was determined based on the plant's morphological characters and mineral contents (Zn and P) of plants and soil. Survival of P. aeruginosa in the field was validated using Antibiotic Intrinsic patterns (AIP). The results indicated that the combination treatment of P. aeruginosa liquid formulation and organic fertilizer (farmyard) (T3) produced the highest biometric parameters and mineral (Zn and P) content of the groundnut plants and the soil. This outcome is likely attributed to the mineral solubilizing capability of P. aeruginosa. Furthermore, the presence of farmyard manure increased the metabolic activity of P. aeruginosa by inducing its heterotrophic activity, leading to higher mineral content in T3 soil compared to other soil treatments. The AIP data confirmed the presence of the applied liquid inoculant by exhibiting a similar intrinsic pattern between the in vitro isolate and the isolate obtained from the fields. In summary, the Zn and P solubilization ability of P. aeruginosa facilitates the conversion of soil-unavailable mineral form into a form accessible to plants. It further proposes the utilization of the liquid formulation of P. aeruginosa as a viable solution to mitigate the challenges linked to solid-based biofertilizers and the reliance on mineral-based chemical fertilizers.
STRUCTURE AND REACTIVITY OF HALOGENATED GC PNA BASE PAIRS – A DFT APPROACH (Article)
(Editorial board of Journal of Experimental Biology and Agricultural Sciences, 2023-11-30) Ranjithkumar, Rajamani; Indumathi, K; Srimathi, P; Praveena, G; Ling, Shing Wong; Sinouvassane, Djearamane
The present study explored the structural and reactivity relationship of halogenated G-C PNA base pairs using density functional theory (DFT) calculations. The halogens such as F, Cl, and Br are substituted by replacing H atoms involved in H-bonds of the base pairs. All structures were optimized using the B3LYP/6-311++G** theory level, and positive frequencies confirmed their equilibrium states. To understand the structural variations of the considered halogenated systems, the bond distances of R─X, R─H, and X/H•••Y and the bond angles of R─X•••Y were analyzed. The obtained structural parameters and interaction energies are comparable with the previous theoretical reports. In addition, the interaction energies (Eint) and quantum molecular descriptors (QMD) are also calculated to understand the difference between halogenated PNA systems and their non-halogenated counterparts. In this study, the enhancement in the reactivity properties of halogenated PNA systems has been demonstrated, which indicates their improved responsive characteristics in various chemical reactions. Based on the available results, the halogenated PNA systems, carefully considering their substitutional position, facilitate better accommodation for the triplex formation of dsDNA/dsRNA. Therefore, it is concluded that the improved reactivity properties of halogenated PNA base pairs would make them potential candidates for various biological applications.
A SYSTEMATIC INVESTIGATION OF LUMINESCENT SCHIFF BASES: PHOTOPHYSICAL AND DFT STUDIES (Article)
(Elsevier B.V., 2023-12) Sowmya, Ramkumar; Kaviarasi, R; Kavyasri, E; Sathya Priyadarshini, G
Conjugated molecular materials with fused rings are of considerable interest in area of organic electronics, because of their excellent charge carrier mobility and high stability. A highly Conjugated new Schiff base molecules have been designed, synthesized from p-hydroxyacetophenone, 1-naphthaldehyde and o-dianisidine, and characterized by standard spectroscopic techniques such as FT IR, NMR and Mass Spectral studies. DFT studies are performed to optimise the geometry of the molecule to study the electronic properties. From the DFT studies, the energy gap between first singlet and triplet excited state are found to be 0.102 eV, the value confirmed that molecule possessed better intersystem crossing ability. In order to evaluate the photostability of the molecule, the photophysical properties in various solvents (DMF, DMSO, acetonitrile, and ethanol) at different intervals of time were investigated systematically to demonstrate the relationships between molecular structures and photophysical properties. The results obtained indicated that the molecule showed good stability towards in DMSo medium as compared to the other solvents. The studies of electronic, optical and structural properties of the compound SB proves it to be a more efficient functional photovoltaic organic materials.
PLANT EXOSOMES: NANO CONVEYORS OF PATHOGEN RESISTANCE (Review)
(Springer, 2023-12) Subha, D; AnuKiruthika, R; Harsha, Sreeraj; Tamilselvi, K S
The entry of a pathogen into a plant host is a complex process involving multiple steps. Survival techniques from the pathogen and the defense mechanisms of the plant lead to a plethora of molecular interactions during the operation. Plant extracellular vesicles, especially the exosomes in the size range of 50-150 nm play a crucial role in plant defense. They act as signalosomes capable of transporting bioactive lipids, proteins, RNA and metabolites between the host and the pathogen. Recent research works have revealed that anti-microbial compounds, stress response proteins and small RNA are among the contents of these extracellular vesicles. The current review article analyses the cruciality of the cross-talk between the host and the pathogen organized through trafficking of small RNA via exosomes towards RNA induced gene silencing in the pathogenic organisms. Recent studies have shown that extracellular vesicles released by both plants and the pathogens, play a crucial role in cross-kingdom communication, thereby regulating the host response and contributing to plant immunity. An in-depth understanding of the mechanism by which the EVs mediate this inter-species and cross-kingdom regulation is currently needed to develop sustainable plant-protection strategies. The review highlights on the latest advances in understanding the role of EVs in establishing host-pathogen relationship, modulating plant immunity and approaches for how these findings can be developed into innovative strategies for crop protection.