Anisotropic nanocatalysts have attracted considerable attention in comparison to bulk/nanocatalysts for their enhanced activity and reactivity. The demand toward anisotropic palladium (Pd) ...nanostructures has increased rapidly in the field of catalysis. Pd is a well-known active catalyst for several carbon–carbon (C–C) cross-coupling reactions; among them, the Suzuki–Miyaura cross-coupling reaction is one of the most versatile and dominant methods for constructing the extraordinarily useful unsymmetrical biaryls and also for hydrogenation of organic contaminants like p-nitrophenol (p-NP). This paper provides a brief explanation about the controlled synthesis, characterization, and catalytic activity of well-defined palladium nanocubes (Pd NCs) prepared by a seed-mediated method. The synthesized monodispersed Pd NCs were characterized by spectroscopic and microscopic tools such as UV–visible, XRD, FESEM, HRTEM, and EDS analyses. Pd NCs proved as an efficient catalyst for Suzuki–Miyaura cross-coupling reactions and p-NP reduction. The catalyst shows enhanced activity, greater stability, and higher selectivity with remarkable recyclability up to 92% for five consecutive cycles. The catalytic performance of the synthesized Pd NCs was also studied in the reduction of the organic contaminant p-NP, which showed an excellent performance screening of 99% conversion in 6 min.
Efficacy of blue (462 ± 3 nm) Light emitting diode (LED) illumination to inactivate the foodborne pathogens like Escherichia coli and Staphylococcus aureus in the presence of exogenous ...photosensitizer (curcumin) was studied in vitro. The effect of temperature, concentration of photosensitizer and incubation time with photosensitizer for microbial inactivation was investigated and sublethal injury of cells was determined. Mechanism of inactivation by the combination of photosensitizer and blue light was also examined. A maximum reduction of 5.94 ± 0.22 and 5.91 ± 0.20 log CFU/ml was obtained for E. coli and S. aureus, respectively, when treated with photosensitizer (20 μM) at 13 J/cm2 of blue light. There was no significant change in the inactivation of these pathogens both at 9 °C and 27 °C in the presence of photosensitizer. Even, the incubation with the photosensitizer didn't show any significant difference on the inactivation of these food-borne pathogens. Sublethal injury (>90% injury) was also observed for the cells treated with photosensitizer and blue light simultaneously. Confocal laser scanning microscopy analysis revealed that membrane integrity was disturbed due to photodynamic activity of curcumin in both the bacteria. Further, both cells produced intracellular reactive oxygen species by the action of photosensitizer and blue light. Scanning electron microscopy of E. coli and S. aureus cells treated with photosensitizer and blue light showed morphological changes in the cell wall compared to untreated group. The study indicated that photodynamic inactivation of foodborne pathogens using LED-based photosensitization can be explored as a potential technique for food safety.
•Combination of photosensitizer and blue light (462 nm) had synergistic effect on inactivation of E. coli and S. aureus.•Inactivation of Food-borne pathogens increased as the photosensitizer concentration increased.•Processing temperature and pre-illumination incubation didn’t affect the inactivation efficiency.•Mode of action can be attributed to the loss of membrane integrity caused by the production of ROS.
•First report on the application of US, PS and BL on liquid foods like orange juice.•PS + BL treatment had synergistic effect on inactivation of E. coli and S. aureus.•Ultrasound and photodynamic ...inactivation had additive effect on E. coli reduction.•TPC, TFC and hesperidin content was not significantly altered by these treatments.•US and BL in presence of PS reduced ascorbic acid content and antioxidant activity.
Efficiency of blue (462 ± 3 nm) light emitting diode (LED) illumination to inactivate Escherichia coli and Staphylococcus aureus in the presence of exogenous photosensitizer (curcumin) was studied in freshly squeezed orange juice. Further, the combinational effect of ultrasound (US), photosensitizer (PS) and blue light (BL) on inactivation of microbes was evaluated. The effect of process parameters such as concentration of PS, US and volume of the juice on E. coli and S. aureus inactivation was also investigated. The US alone and PS + BL treatments resulted in 3.02 ± 0.52 and 1.06 ± 0.13 log reduction of E. coli; 0.18 ± 0.14 and 2.34 ± 0.13 log reduction of S. aureus, respectively. The combination of PS + US + BL treatment at optimized conditions resulted in 2.35 ± 0.16 log reduction of S. aureus. An additive effect on the inactivation of E. coli (4.26 ± 0.32 log reduction) was observed with PS + US + BL combination treatment. The US treatment showed significant change in cloud value, colour and browning index of orange juice. The combinational non-thermal processes (PS + BL and PS + US + BL) did not have any significant effect on total phenolic content, total flavonoid content, and hesperidin content of the orange juice. However, these processes affected ascorbic acid content and antioxidant activity negatively. Thus, this study indicated that photodynamic inactivation of E. coli and S. aureus using LED-based photosensitization in fruit juices could be a potential method for microbial inactivation. Nevertheless, the effect on quality parameters needs to be considered while optimizing the process.
Abstract
Surface‐enhanced enhanced Raman spectroscopy (SERS) has emerged as a powerful analytical technique for ultrasensitive and label‐free detection of chemical species, with numerous applications ...in various fields. Recently, 2D MXenes, have evoked substantial intrigue as promising substrates for SERS. Hence, a comprehensive understanding of the developments in the Raman effect and the mechanisms involved in SERS is highly crucial. The review reflects the advances, working principle, and dual mechanisms, including SERS's electromagnetic and chemical mechanisms. Noble metal nanostructures are highly prioritized as SERS substrates owing to their excellent sensitivity. However, due to certain disadvantages that they pose, metal‐free SERS substrates with exceptional tunable properties are extensively researched in the current days. The combination of 2D MXenes and nanostructures can be effective in producing enhanced SERS signals. SERS performance of different MXene‐based materials is emphasized. The performance of this combination is credited to their large surface‐to‐volume ratio, good electrical conductivity, and surface‐terminated functionalities. The recent advancements in MXenes and MXenes‐based heterostructures driven SERS sensing concerning the structural design of the material, its performance, and the mechanisms are studied. Finally, a detailed conclusion is provided with the challenges and future perspectives for designing 2D materials for efficient SERS sensors.
Elucidation of genome size (GS), genetic and phenotypic variation is the fundamental aspect of crop improvement programs. Mulberry is a cross-pollinated, highly heterozygous tree eudicot, and ...comprised of huge ploidy variation with great adaptability across the world. However, because of inadequate information on GS, ploidy-associated traits, as well as the correlation between genetic and phenotypic variation hinder the further improvement of mulberry. In this present research, a core set of 157 germplasm accessions belonging to eight accepted species of Morus including promising functional varieties were chosen to represent the genetic spectrum from the whole germplasm collection. To estimate the GS, accessions were subjected to flow cytometry (FCM) analysis and the result suggested that four different ploidies (2n = 2x, 3x, 4x, and 6x) with GS ranging from 0.72±0.005pg (S-30) to 2.89±0.015pg (M. serrata), accounting~4.01 fold difference. The predicted polyploidy was further confirmed with metaphase chromosome count. In addition, the genetic variation was estimated by selecting a representative morphologically, diverse population of 82 accessions comprised of all ploidy variations using simple sequence repeats (SSR). The estimated average Polymorphism Information Content (PIC) and expected heterozygosity showed high levels of genetic diversity. Additionally, three populations were identified by the model-based population structure (k = 3) with a moderate level of correlation between the populations and different species of mulberry, which imply the effect of genetic variation instead of ploidy on trait plasticity that could be a consequence of the high level of heterozygosity imposed by natural cross-pollination. Further, the correlation between ploidies, especially diploid and triploid with selected phenotypic traits was identified, however, consistency could not be defined with higher ploidy levels (>3x). Moreover, incite gained here can serve as a platform for future omics approaches to the improvement of mulberry traits.
The rapid, ultralow detection, degradation, and complete removal of pesticides demand the design of potential substrates. Herein, we discussed gold nanorods (Au NRs) as the potential substrate for ...the naked eye detection and degradation of two common and broad-spectrum pesticides, chlorpyrifos (CPF) and malathion (MLT), up to 0.15 ppt concentration within 2 min. Under certain environmental conditions, both the pesticides degraded and adsorbed on the surface of Au NRs. The degraded moieties of CPF and MLT on the surface of Au NRs formed side-to-side and end-to-end interactions, respectively, leading to a long-range assembly. This shows that no external agent is required, and only CPF and MLT analytes are quite enough for the formation of assembly of Au NRs. Assembly of Au NRs is confirmed by transmission electron microscopy (TEM) analysis, and degradation is supported by Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, and gas chromatography–mass spectrometry (GC–MS) analyses. Au NRs were recovered and reused for four consecutive cycles. The fast and ultralow detection of pesticides demonstrates that Au NRs are a potential substrate for the detection and degradation of pesticides.
The diminishing nutritional quality of rice with increasing concentrations of atmospheric CO
2
is currently a major global concern. The present study was designed with the objective of assessing the ...impact of biofertilisers on grain quality and iron homeostasis in rice under elevated CO
2
. A completely randomised design with four treatments (KAU, POP (control), POP+Azolla, POP+PGPR, and POP+AMF), each replicated three times under ambient and elevated CO
2
conditions, was followed. The analysed data revealed that yield, grain quality, and iron uptake and translocation were modified in an unfavourable manner under elevated CO
2
, which was reflected in the lower quality and iron content of the grains. The response of iron homeostasis in the experimental plants to the application of biofertilisers, especially plant-growth-promoting rhizobacteria (PGPR), under elevated CO
2
strongly suggests the possibility of utilising them for designing iron management strategies for achieving higher quality in rice.
Abstract Major research interests on quantum key distribution (QKD) are primarily focused on increasing 1. Point-to-point transmission distance (1000 km). 2. Secure key rate (Mbps). 3. Security of ...quantum layer (device-independence). It is great to push the boundaries in these fronts but these isolated approaches are neither scalable nor cost-effective due to requirements of specialised hardware and different infrastructure. Current and future QKD network requires addressing different set of challenges apart from distance, key rate and quantum security. In this regard, we present ChaQra—a sub quantum network with core features as 1. Crypto agility (integration in the already deployed telecommunication fibres). 2. Software defined networking (SDN paradigm for routing different nodes). 3. reliability (addressing denial-of-service with hybrid quantum safe cryptography). 4. upgradability (modules upgradation based on scientific and technological advancements). 5. Beyond QKD (using QKD network for distributed computing, multi-party computation etc). Our results demonstrate a clear path to create and accelerate quantum secure Indian subcontinent under national quantum mission.
Maize is an important industrial crop where yield and quality enhancement both assume greater importance. Clean production technologies like conservation agriculture and integrated nutrient ...management hold the key to enhance productivity and quality besides improving soil health and environment. Hence, maize productivity and quality were assessed under a maize-wheat cropping system (MWCS) using four crop-establishment and tillage management practices FBCT-FBCT (Flat bed-conventional tillage both in maize and wheat); RBCT-RBZT (Raised bed-CT in maize and raised bed-zero tillage in wheat); FBZT-FBZT (FBZT both in maize and wheat); PRBZT-PRBZT (Permanent raised bed-ZT both in maize and wheat, and five P-fertilization practices P
(100% soil applied-P); P
+ 2FSP (50% soil applied-P + 2 foliar-sprays of P through 2% DAP both in maize and wheat); P
+ PSB + AM-fungi; P
+ PSB + AMF + 2FSP; and P
(100% NK with no-P) in split-plot design replicated-thrice. Double zero-tilled PRBZT-PRBZT system significantly enhanced the maize grain, starch, protein and oil yield by 13.1-19% over conventional FBCT-FBCT. P
+ PSB + AMF + 2FSP, integrating soil applied-P, microbial-inoculants and foliar-P, had significantly higher grain, starch, protein and oil yield by 12.5-17.2% over P
besides saving 34.7% fertilizer-P both in maize and on cropping-system basis. P
+ PSB + AMF + 2FSP again had significantly higher starch, lysine and tryptophan content by 4.6-10.4% over P
due to sustained and synchronized P-bioavailability. Higher amylose content (24.1%) was observed in grains under P
+ PSB + AMF + 2FSP, a beneficial trait due to its lower glycemic-index highly required for diabetic patients, where current COVID-19 pandemic further necessitated the use of such dietary ingredients. Double zero-tilled PRBZT-PRBZT reported greater MUFA (oleic acid, 37.1%), MUFA: PUFA ratio and P/S index with 6.9% higher P/S index in corn-oil (an oil quality parameter highly required for heart-health) over RBCT-RBCT. MUFA, MUFA: PUFA ratio and P/S index were also higher under P
+ PSB + AMF + 2FSP; avowing the obvious role of foliar-P and microbial-inoculants in influencing maize fatty acid composition. Overall, double zero-tilled PRBZT-PRBZT with crop residue retention at 6 t/ha per year along with P
+ PSB + AMF + 2FSP while saving 34.7% fertilizer-P in MWCS, may prove beneficial in enhancing maize productivity and quality so as to reinforce the food and nutritional security besides boosting food, corn-oil and starch industry in south-Asia and collateral arid agro-ecologies across the globe.
Fresh-cut fruits are susceptible for microbial contamination during handling and storage. Hence, there is a need for minimal processing of such foods using non-thermal technology that can inactivate ...both bacterial pathogens and undesirable enzymes while retaining the quality. In this regard, synergistic effect of light emitting diode (LED) based blue light (BL) and natural exogenous photosensitizer- curcumin (PS) on the inactivation of bacterial pathogens (
Escherichia coli, Staphylococcus aureus
), and enzymes (polyphenol oxidase, peroxidase, bromelain) of fresh-cut pineapple slices were evaluated. The effect of photodynamic treatment (PS+BL) on quality attributes like color, phenolics, flavonoids, ascorbic acid content and antioxidant activity was also investigated. The PS+BL treatment at optimized conditions resulted in 3 and 4 log reduction of
E. coli
and
S. aureus
, respectively. PS(100 μM)+BL treatment led to partial inactivation of polyphenol oxidase (33.5%) and peroxidase (25.7%), synergistically, but preserved desired enzyme bromelain. The PS+BL didn’t show any significant (p<0.05) consequence on color, phenolics, flavonoids and antioxidant activity, while it affected the ascorbic acid content negatively (reduced by ~30%). The current investigation showed that the photodynamic inactivation of
E. coli
and
S. aureus
using LED-based photosensitization in fresh-cut fruit slices could be used as a potential method for microbial control although some phytochemical losses.
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