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A new type of optically pure primary amino aromatic Tf-amide organocatalyst can be easily prepared from 8-amino-1-tetralone, and its chemical behavior was investigated in the context of asymmetric aldol and Mannich reactions. Most notably, the asymmetric aldol reaction proceeded smoothly in brine. [ABSTRACT FROM AUTHOR]

• Laser scribing of lignin-derived graphene coupled in-situ decoration of Mg-Al LDH. • Functionalized LSG prevents self-agglomeration of delaminated Mg-Al LDH. • A neutral electrolyte, PAAS/K2SO4 was used for flexible MSC application. • Optimal Mg-Al LDH infused Lignin-LSG reveals enhanced electrochemical performance. Innovations in the synthesis of hybrid materials have led to technology advancement of the microsupercapacitor. Delaminated layered double hydroxide (LDH) reduces self-agglomeration and increases energy density in graphene-based supercapacitors. The incorporation of delaminated LDH with oil palm lignin derived laser scribed graphene in neutral PAAS/K 2 SO4 gel electrolyte for flexible microsupercapacitor applications was investigated. Various concentrations of positively charged sucrose-delaminated Mg-Al LDH nanosheets produced through the coprecipitation method were hybridised with negatively charged oil palm lignin-derived laser scribed graphene (L-LSG) through electrostatic interaction. Hybrid laser scribed graphene developed from delaminated Mg-Al LDH at a concentration of 10 gL−1 (L-LSG/D-MgAl-10) had the largest surface area of 49.335 m2g−1. The incorporation of Mg-Al LDH nanosheets on l-LSG were further validated by FESEM, TEM, XRD, Zeta potential and other characterizations. It also had the highest areal capacitance and energy density, measuring 40 mFcm−2 and 0.00296 mWhcm−2, respectively, at a current density of 0.08 mAcm−2. The fabricated microsupercapacitor has exceptional bending capabilities and capacitance retention of 89.2% after 5000 cycles. In summary, by inducing additional pseudocapacitance, delaminated Mg-Al LDH improved the overall effectiveness of the oil palm lignin derived graphene electrode compared to pristine graphene. [Display omitted] [ABSTRACT FROM AUTHOR]

Failure of chemical control methods in conferring protection against Cercospora leaf spot (CLS) disease in mung bean crop led to the investigation of biocontrol agents for effective management of the CLS. The current study was focused on increased defense response (histochemical and biochemical) in mung bean plants by alginate pellet formulation of endophytic Amycolatopsis sp. SND-1 (SND-1) against CLS disease. The sodium alginate bioformulation of SND-1 was prepared by standard method using CaCl2 and evaluated for viability and contamination. Greenhouse study of prepared SND-1 formulation was performed on mung bean plants against CLS infection. Further, the acceleration of histochemical depositions (lignin, H 2 O 2 and phenol) by differential staining methods and biochemical defense enzymes like PAL, GLU, and POX, phenolic, flavonoid and chlorophyll contents and cell death analysis were evaluated through microscopic and spectroscopic studies. The viability assay of the prepared formulation exhibited a negligible reduction in SND-1 spores (99.5% to 86.55%) throughout the six months of storage period. In-vivo (Greenhouse) study exhibited increased growth parameters in alginate pellet formulation of SND-1challenged with Cercospora pathogen (SND-1+Pathogen) treated mung bean plants in comparison with Control (SDW) and only pathogen infested plants. Consequently, the plants with SND-1+Pathogen treatment showed significant reduction in disease severity up to 56%. Furthermore, the microscopic evaluation of histochemical defense markers depicted increased deposition of lignin (82.43±0.31%), H 2 O 2 (47.97±0.66%), and phenol (76.74±0.79%) and cell death analysis through microscopic observation exhibited lesser dead cells of 31% in SND-1+Pathogen treatment in comparison with other treatments. Defense patterns at biochemical level hinted the elevation in activities of defense enzymes like PAL, GLU and POX at 12 and 24 h post pathogen inoculation (hpi) in SND-1+Pathogen treatment. The formulation treatment with pathogen (SND-1+Pathogen) also substantiated that enhanced total phenolic, flavonoid, and chlorophyll contents at different time intervals. Overall the present investigation showed that Amycolatopsis sp. SND-1 formulation confers the protection in mung bean upon Cercospora infection and it might be an effective eco-friendly approach towards sustainable agriculture. [ABSTRACT FROM AUTHOR]

Lignin is a renewable natural resource that could be derived from oil palm empty fruit bunches. It has generated significant interest as a precursor in synthesizing graphene as anode and cathode material for supercapacitors. In this paper, we report the synthesis of 3D hierarchical Laser Scribed Graphene (LSG) on a flexible polyimide substrate from lignin extracted from empty fruit bunches (EFB) of oil palm for microsupercapacitor applications. The intensity and speed of the laser have been tuned to yield densely compacted oil palm lignin LSG at a laser power of 70% and a speed of 30% (OPL-LSG 7030). OPL-LSG 7030 possessed lower equivalent series resistance of 60.1 Ω and a larger crystalline size of ∼31 nm than the rest of the tested samples. It exhibited exceptional areal capacitance of 30.77 mFcm−2 at a current density of 0.08 mAcm−2, an energy density of 0.00176 mWhcm−2 and a power density of 0.25 mWcm−2 when using a unique neutral PAAS/K 2 SO 4 gel electrolyte. It achieved excellent capacitance retention of 88.4% after 5000 charge/discharge cycles and remarkable mechanical stability of 95% after 400 bending cycles. Furthermore, electrochemical studies revealed the redox properties of readily available quinone/ hydroquinone in the oil palm lignin, which could be inherited in graphene electrodes through a feasible and affordable approach for flexible green energy storage applications. [Display omitted] • A new EFB lignin derived 3D LSG was developed via one-step laser scribing method. • A unique PAAS/K 2 SO 4 electrolyte was used to assemble flexible microsupercapacitor. • LSG produced at higher laser power and lower speed has highly porous structure. • OPL-LSG 7030 exhibits excellent electrochemical and bending performance. [ABSTRACT FROM AUTHOR]

Bismuth telluride (Bi2Te3), due to its thermoelectric properties, is an interesting semiconducting material for optoelectronics and energy conversion devices; still, it has limited stability and durability. Under high pressure, we can fine-tune its performance, potentially enhancing its capabilities. The presented work uses the semi-automatic Reddy tube to explore the behavior of bismuth telluride under dynamic pressure. Commercially available bismuth telluride was purchased and subjected to different numbers of shock pulses of 100, 200, 300, and 400 with 2 MPa transient pressure and 864 K transient temperature. XRD, Raman, UV-DRS, PL, and SEM were used to characterize Bi2Te3 and shock-loaded Bi2Te3. The XRD and Raman study confirms that the Bi2Te3 underwent phase transition from Bi2Te3 to Bi4Te5 (rhombohedral to hexagonal) at 300 shock pulses. The optical property of Bi2Te3 was determined using UV-DRS and PL; the bandgap and PL intensity changed with respect to the number of shock pulses. A scanning electron microscope was used to analyze sample morphology. Our findings reveal the reversible phase transition of bismuth telluride from Bi2Te3 to Bi4Te5 under dynamic shock waves, something that has not been reported earlier. Using traditional synthesis methods, Bi4Te5 consume a lot of time, leading to impurities and problems of sample quality. Our results reveal that a rapid and reversible phase transition and unique response to dynamic shock waves will allow excellent technological applications without requiring lengthy and complex synthesis methods, offering enhanced stability and potential advancements in energy conversion devices. The process detailing how shock waves initiate the phase transition is explained. [ABSTRACT FROM AUTHOR]

A straightforward, highly chemoselective hydrogenation of α,β-unsaturated aldehydes was developed using unsupported nanoporous gold (AuNPore) as a heterogeneous catalyst with bio-renewable formic acid (HCO2H) as hydrogen source. Various α,β-unsaturated aldehydes were reduced to their corresponding allylic alcohols in good to high chemical yields with excellent selectivity. AuNPore offers several attractive features as a catalyst, such as high activity and selectivity, easy recyclability, and no leaching. [ABSTRACT FROM AUTHOR]

In this study, the unique characteristics of chitosan, reduced graphene oxide (rGO) and cerium oxide (CeO 2) based hybrid bionano-composites make a carrier for various drug delivery and antimicrobial applications. The recent literatures shown that addition of biopolymers to rGO and CeO 2 based nanocomposites exhibit excellent performance in design and development of biosensors, wound dressings, electrodes, microfluidic chips, drug delivery systems and energy storage applications. Chitosan (CS), reduced graphene oxide (rGO) mixed with cerium oxide (CeO 2) to form CS-rGO and CS-rGO-CeO 2 hybrid bionano-composites using precipitation method. The physiochemical characterization of casted nanocomposite sheet was done using FTIR, XRD, UV–Vis spectrum, SEM and TGA. The XRD results of CS-rGO-CeO 2 revealed that the nanoparticle was found to be crystalline structure. FTIR revealed that nitrogen functionalities of CS interacted with rGO-CeO 2 to form hybrid nanocomposites. The thermal gravimetric analysis (TGA) showed that the CS-rGO-CeO 2 has better thermal stability up to 550 °C. The SEM confirms the surface morphology of CS-rGO-CeO 2 has large surface area with smooth surface. Moreover, the antibacterial properties of nanocomposites exhibit excellent zone of inhibition against Staphylococcus aureus and Escherichia coli. The NIH3T3 cell line evaluations showed superior cell adhesion on hybrid nanocomposites. Hence bionano-composite based on CS, rGO and CeO 2 are potential biomaterials for drug delivery and antibacterial applications. [Display omitted] • CS-rGO-CeO 2 bionano-composite was prepared by simple, facile one-pot co-precipitation method. • CS-rGO-CeO 2 bionano-composite has better biocompatibility and superior antimicrobial efficacy against tested pathogens. • CS-rGO-CeO 2 bionano-composite exerted strong drug release and significant cytotoxicity against A549 cell lines. [ABSTRACT FROM AUTHOR]

Anthracnose is a devastating disease caused by the fungus Colletotrichum lindemuthianum (CL) in Vigna radiata (L.) R. Wilczek (mung bean). In the present study, an eco-friendly approach to control anthracnose infection, growth promotion and enhancement of defense response in mung bean plants using endophytic actinomycetes was performed. Among the 24 actinomycetes isolates from the Cleome rutidosperma plant, the isolate SND-2 exhibited a broad spectrum of antagonistic activity with 63.27% of inhibition against CL in the dual culture method. Further, the isolate SND-2 was identified as Streptomyces sp. strain SND-2 (SND-2) through the 16S rRNA gene sequence. In-vitro screening of plant growth trials confirmed that SND-2 has the potential to produce indole acetic acid, hydrogen cyanide, ammonia, phosphate solubilization, and siderophore. The in-vivo biocontrol study was performed with exogenous application of wettable talcum-based formulation of SND-2 strain to mitigate CL infection in mung bean seedlings. The results displayed maximum seed germination, vigor index, increased growth parameters, and lowest disease severity (43.63 ± 0.73) in formulation treated and pathogen challenged mung bean plants. Further, the application of SND-2 formulation with pathogen witnessed increased cellular defense through the maximum accumulation of lignin, hydrogen peroxide and phenol deposition in mung bean leaves compared with control treatments. Biochemical defense response exhibited upregulation of antioxidant enzymes such as phenylalanine ammonia-lyase, β-1,-3-Glucanase, and peroxidase enzymes activities with increased phenolic (3.64 ± 0.11 mg/g fresh weight) and flavonoid (1.14 ± 0.05 mg/g fresh weight) contents in comparison with other treatments at 0, 4, 12, 24, 36, and 72 h post pathogen inoculation. This study demonstrated that formulation of Streptomyces sp. strain SND-2 is a potential source as a suppressive agent and plant growth promoter in mung bean plants upon C. lindemuthianum infestation and witnesses the elevation in cellular and biochemical defense against anthracnose disease. • Anthracnose is a devastating disease in Vigna radiata (L.) R. Wilczek (mung bean). • Endophytic actinomycetes are the excellent biocontrol and growth promoting agents. • Streptomyces sp. SND-2 exhibited biocontrol growth promotion in mung bean seedlings. • SND-2 strain enhanced cellular defense in mung bean against anthracnose infection. • SND-2 strain triggered biochemical defense in mung bean against anthracnose infection. [ABSTRACT FROM AUTHOR]

The biopolymer melanin is reported for many biological processes to secure biological entities over unfavorable environmental factors. The present study aimed to isolate soil fungi and screen for melanin production. The potent fungus was identified as Penicillium citrinum NP4 based on morphological and molecular characterization with accession number OP070954. Using standardized tyrosine broth conditions melanin was produced by NP4 and extracted by acidification. Extracted melanin exhibited maximum UV–visible absorption at 223 nm; FTIR peaks validate the occurrence of C O, C N, C H, and C C functional groups present in the indole/pyrrole structure. TLC analysis exhibited a prominent single band with a Retardation factor (Rf) of 0.68, resonance peaks at 6.621, 7.061, and 7.185 ppm exhibited aromatic hydrogen in the indole/pyrole system in 1H NMR. The EDX peaks confirm the presence of carbon, oxygen, sulfur, and nitrogen elements which are the key factors in melanin structure, and TGA reports the thermal stability of the melanin. An in silico molecular docking approach on lung cancer causing proteins EGFR (3g5z), KRAS (6vc8), and TP53 (8 dc4) were conducted to determine the active binding sites of the melanin, and proteins exhibited binding affinity of −8.0 for 3g5z, −9.8 for 6vc8, and − 10.1 kcal/mol for TP53 protein with melanin. Anticancer activity of the melanin showed significant inhibition of A549 cells in dose-dependent mode with significant IC 50 of 65.49 μg/mL; apoptotic examination reveals 46.14 % apoptosis for melanin and 46.36 % apoptosis for standard drug (cisplatin). Melanin exhibited good photoprotection capacity at 1 μg/mL. In conclusion, the extracted melanin exhibited significant results on many biological applications and it can be used in the pharmaceutical field to avoid chemical-based drugs. • Isolated Penicillium citrinum NP4 from soil showed potency for melanin production. • Melanin was produced from NP4 strain and extracted by acidification. • Characterization confirms the nature of the melanin. • Molecular docking reports binding affinity of melanin with cancer causing proteins. • NP4-melanin exhibited the significant anticancer efficacy on A549 cells and photoprotection. [ABSTRACT FROM AUTHOR]

AChE interacting with spiropyrrolidines, 4h. [Display omitted] New class of highly functionalized dispiropyrrolidine tethered indandione heterocycles in good yield were obtained through stereo- and regioselective single-pot three component cycloaddition methodology between benzylidene-indandione and non-stabilized azomethine ylide. The ylide generated from active diketone and aminophenylpropanoic acid via dehydration/decarboxylative pathway. The synthesized dispiropyrroldine comprising indandiones were elucidated through 1H and 13C NMR spectroscopic analysis, the stereo and regioselective formation of the dispiropyrrolidine were unequivocally assigned by X-ray diffraction analysis. Compound thus synthesized were assayed as potential inhibitor for the treatment of AD. Spiropyrrolidine 4h that bearing methoxy group on the phenyl ring showed significant activity, IC 50 of 3.24 ± 0.25 and 10.25 ± 0.16 μM against acetyl and butyryl cholinesterase enzyme, respectively. The lead compound 4h executed to investigate for their docking simulation that showed strong binding affinity with binding site of the cholinesterase protein. [ABSTRACT FROM AUTHOR]

An efficient method was developed for the synthesis of highly substituted naphthalenes through rhodium-catalyzed oxidative benzannulation of N-pivaloylanilines with internal alkynes. The benzannulation reaction proceeded smoothly through dual C−H bond activation to produce the corresponding highly substituted naphthalene products in satisfactory to good yields. [ABSTRACT FROM AUTHOR]

series of benzimidazole-tethered oxazepine heterocyclic hybrids has been synthesized in good to excellent yields from an N-alkylated benzimidazole 2-carboxaldehyde, which in turn was accomplished from o-phenylenediamine in three good yielding steps. The calculated molecular structure of compounds 2-methyl-4-(2-((phenylimino)methyl)-1H-benzo-[d]imidazol-1-yl)-butan-2-ol 9 and 10 3,3-dimethyl-N-phenyl-1,2,3,5-tetrahydrobenzo-[4,5]imidazo[2,1-c][1,4]oxazepin-5-amine using the B3LYP/6-31 G(d, p) method were found to agree well with their X-ray structures. The charge distributions at the different atomic sites were computed using the natural bond orbital (NBO) method. The regions of electrophilic and nucleophilic reactivity were shown using a molecular electrostatic potential (MEP) map. In addition, the frontier molecular orbitals of these compounds were discussed at the same level of theory. Nonlinear optical (NLO) properties have also been investigated by computational hyperpolarizability studies, and it was found that Compound 9 is the best candidate for NLO applications. [ABSTRACT FROM AUTHOR]

An efficient method was developed for the synthesis of 1-naphthols through NaO tBu-promoted SNAr reaction of ortho-haloacetophenones followed by Lewis acid CuI-catalyzed intramolecular condensation and isomerization. 1-Naphthol derivatives were obtained in satisfactory yields from aryl bromide and aryl iodide substrates. [ABSTRACT FROM AUTHOR]