Vis Spectrophotometer Research Articles

A novel method for biosynthesis of copper oxide nanoparticles using banana blossom and E-waste: characterization and application in malachite green dye removal through response surface methodology optimization

Textile dyes pose a significant threat to water resources, adversely affecting living organisms. Treating such contaminated water demands sophisticated technology, often expensive and requiring meticulous care. The use of copper oxide nanoparticles as a photocatalyst for degrading textile dyes is a promising solution. However, conventional chemical synthesis of copper oxide nanoparticles can be lengthy and environmentally unfriendly. To address this, a green technology approach was adopted in this research. A novel process was developed by extracting copper sulfate solution from E-waste, utilizing it as a precursor. Simultaneously, banana blossom extract (Musa paradisiaca) acted as a reducing agent in the biosynthesis of copper oxide nanoparticles, serving as a biocatalyst for malachite green dye removal. Optical characterization using a UV–Visible spectrophotometer revealed a peak around ~250 nm, indicating the presence of copper oxide. Fourier-transform infrared spectroscopy identified chemical groups within the sample, and X-ray diffraction spectroscopy confirmed its crystalline nature. The morphology of the synthesized copper oxide nanoparticles was investigated using transmission electron microscopy and energy-dispersive X-ray analysis. The potential application of CuO-NP in malachite green dye removal was successfully demonstrated, achieving a dye removal efficiency of 92% under optimal conditions. A quantitative analysis of dye removal was conducted and optimized using response surface methodology and analysis of variance, which indicated significant interactions among the variables. This eco-friendly and cost-effective approach showcases the feasibility of green technology in addressing environmental challenges associated with textile dye contamination.

Synthesis of aluminum oxide nanoparticles using seeds of Carica papaya and evaluation of it for antimicrobial, antioxidant, and photocatalysis activity

The present work is aimed at the synthesis of aluminum oxide nanoparticles (AlONPs) using the seed extract of Carica papaya. The aluminum oxide nanoparticles were evaluated using X-ray diffraction (XRD), Fourier transforms infrared (FTIR), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray (EDX), ultraviolet–visible (UV–Vis) spectrophotometer, and zeta potential, respectively. This work also determines the antimicrobial and antioxidant activity of the seed extract AlONPs against pathogens such as Bacillus cereus (B. cereus), Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and Salmonella enterica (S. enterica) for antibacterial and Aspergillus niger (A. niger) for antifungal. The as-synthesized AlONPs were used for the degradation of EY dye in the presence of visible light. The presence of an absorption peak at a wavelength of 272 nm in the synthesized nanoparticles was detected by UV–Vis spectroscopy analysis. The results of the FTIR study confirmed the existence of various chemicals and functional groups in the 500–4000 cm−1 range. EDX results revealed that it included 68% aluminum and 22% oxygen established the high purity of the AlONPs. The average crystallite size of the synthesized AlONPs was found to be 52 nm by XRD analysis. Using DPPH activity, the synthesized AlONPs showed incredible antioxidant properties of 72.42% inhibition at the maximum concentration of 100 µg/ml. Moreover, it was found that the AlONPs significant antibacterial activity against tested strains viz. B. cereus (20 mm) and also showed antifungal efficacy against A. niger (30 mm) at higher concentrations of AlONPs. The photocatalytic degradation of the dye through the utilization of the synthesized AlONPs was clearly evident through the observation of a shift in color of the Eosin Y dye, transitioning from a deep pink hue to a nearly colorless state after exposure to UV light for 300 min. The green synthesized AlONPs show high photocatalytic degradation of EY 91.41% after 300 min under visible light irradiation. The current investigation has demonstrated that the seed extract of Carica papaya serves as a significant resource for the synthesis of AlONPs through a biological, eco-friendly, and non-toxic approach, while also possessing antibacterial, antioxidant, and photocatalytic properties.

Systematic long-term investigation on Cu2ZnCdS4 wide band gap semiconducting materials for optics and luminescence applications

Copper Zinc Cadmium Sulfide (Cu2ZnCdS4) semiconducting material compound synthesized using a new economic beneficial route. Copper sulfate, zinc sulfate, cadmium sulfate and thiourea salt solutions were utilized for Cu2ZnCdS4 compound formation. Basic characteristics like pH value, electrical conductivity, concentration measurements were investigated for several hundred samples. Optics transmittance was investigated by UV – Vis spectrophotometer within the 350 to 950 nm range. Photo luminescence measurement was examined by using photo–fluorometer. Optic properties of Cu2ZnCdS4 compound were investigated through photo-calorimeter measurements including mixed wavelength bands. The real time investigated noteworthy results from several hundred samples are presented and discussed.

Utilizing Fe2O3-β-CD magnetic nanocomposite for efficient removal of MG dye and Gunner 500 pesticide from wastewater

Among various techniques used for wastewater treatment, photocatalysis is one of the most preferred technique. Here, synthesis of a magnetic β-Cyclodextrin (β-CD) based Fe2O3 nanocomposite was carried out. The characterization of the synthesized materials were carried out by using P-XRD, TGA-DTA, FT-IR, PL, DRS, XPS,TEM and SEM-EDAX to study their different properties. Model pollutants Malachite green (MG) dye and Gunner 500 pesticide were selected for photocatalytic activity. These model pollutants were analysed in presence of Fe2O3 and Fe2O3-β-CD under visible light. Performance was monitored through measuring removal efficiency using UV–Visible spectrophotometer. 89.4 and 88.0 % degradation was observed with MG in 120 min and Gunner 500 in 100 min. Photocatalytic degradation efficiency was observed with initial pollutant concentration MG (10 mg L−1) and Gunner 500 (10 mg L−1) at neutral pH value. Reaction kinetics was measured and first order rate law is applicable with both pollutants. Probable mechanism and degradation pathway of pollutants were proposed. COD also favours degradation and demineralization. Reusability was also studied.

A silver lining in MRSA treatment: The synergistic action of poloxamer-stabilized silver nanoparticles and methicillin against antimicrobial resistance

BackgroundIncreasing antibiotic resistance in bacterial infections, including drug-resistant strains like methicillin-resistant Staphylococcus aureus (MRSA), necessitates innovative therapeutic solutions. Silver nanoparticles are promising for combating infections, but toxicity concerns emphasize the importance of factors like dosage, size, shape, and surface chemistry. Hence, exploring poloxamer as a stabilizing agent to reduce its toxicity and enhance the antibacterial effect on MRSA is investigated. MethodsSilver nanoparticles stabilized with poloxamer (AgNPs@Pol) were synthesized through the chemical reduction method and characterized using UV–visible spectrophotometer, HR-TEM, DLS, and Zeta potential measurements. Subsequently, the antibacterial activity of AgNPs@Pol alone and in combination with methicillin against MRSA and methicillin-susceptible S. aureus (MSSA) was evaluated using the broth microdilution method. ResultsAgNPs@Pol showed significant efficacy against MRSA and MSSA, achieving a 100 % reduction in colony-forming units (CFU) at 9.7 μg/ml. The minimum inhibitory concentration (MIC) against MRSA and MSSA was 8.6 μg/ml and 4.3 μg/ml, respectively. A synergistic effect was observed when AgNPs@Pol was combined with methicillin. Treatment with AgNPs@Pol increased reactive oxygen species (ROS) production in both strains, contributing to its antibacterial activity. Real-time qPCR analysis indicated the downregulation of genes involved in antimicrobial resistance and cell adhesion in both strains. Further, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay demonstrated low cytotoxicity for AgNPs@Pol against MCF-7, MG-63, and NIH-3T3 cell lines. ConclusionThe developed AgNPs@Pol demonstrated extensive colloidal stability, potent antibacterial activity and synergistic effect with methicillin against MRSA and MSSA. Further studies in primary cells and in vivo models may validate its potential for clinical applications.

Innovative S-Scheme heterojunctions: Boosting methylene blue degradation and antimicrobial efficacy with Ni–CoS@S-g-C3N4

The release of waste, including organic dyes from various industries, directly into water bodies significantly contributes to environmental pollution. Consequently, there is a need for photocatalytic materials that can effectively remove harmful pollutants from water, ensuring its purity and safety. Carbon-based photocatalysts have garnered significant attention in this context because of their exceptional stability, high conductivity, and very small band gap. In the current project, a series of CoS, Ni–CoS, and Ni–CoS/S-g-C3N4 with different concentrations of S-g-C3N4 were synthesized using a simple, efficient, and cost-effective co-precipitation technique, while S-g-C3N4 was constructed through a thermal degradation process using thiourea as a precursor. The produced photocatalysts underwent characterization utilizing sophisticated analytical methods including FTIR, XRD, SEM, and EDX. The photocatalytic degradation behavior of the prepared photocatalysts was assessed using a UV–visible spectrophotometer, and the doping of Ni-metal was found to significantly enhance the degradation rate of methylene blue (MB), a standard pollutant dye in the order of CoS < %8Ni–CoS <8%Ni–CoS@50 % S-g-C3N4.the maximum photocatalytic degradation was shown by the nanocomposites (8%Ni–CoS@50 % S-g-C3N4) i.e. 94 %. The EIS spectra for CoS, 8 % Ni–CoS, and Ni–CoS/50 % SCN were analyzed, and their antimicrobial effectiveness was evaluated.

The addition of Bi2WO6 nanoparticles to polyvinyl alcohol film: Improvements in optical, mechanical, and electrical properties

This study deals with the influence of adding Bi2WO6 (BWO) nanoparticles on the optical, structural, dielectric, and mechanical properties of polyvinyl alcohol (PVA). BWO nanoparticles synthesized by solvothermal method were characterized by X-Ray diffraction (XRD) and scanning electron microscope (SEM-EDS). The thick film nanocomposites were analyzed by Fourier Transformed Infrared (FTIR) spectrometer, XRD device, SEM, atomic force microscope (AFM), ultraviolet visible (UV–Vis) spectrophotometer, impedance analyzer, and tensile test machine. While FTIR analyses confirmed the formation of composite structure and the presence of BWO in the composites, AFM views indicated the reduced roughness for composites. Additionally, the UV–Vis light absorption spectra revealed a narrowed band gap in the composites. Moreover, with increasing BWO contribution, gradual increases were recorded in Young's modulus, toughness and % breaking strain parameters. The frequency dependent dielectric properties was also shown that the energy storage ability of the PVA matrix enhances 25 % and 50 % due to 2 % and 3 % BWO additives, respectively. However, the composite with higher ε′ and lower ε″ values than the pure PVA in the entire frequency range was the 2 % BWO-doped nanocomposite. Based on the serious and simultaneously improvements in electrical, optical and mechanical properties, it can be suggested that 2 % BWO additive provides the opportunity to expand the application area of PVA synergistically.

Hydrothermal Growth Zinc Oxide Nanorods for pH Sensor Application

The aim of this work is to apply synthesized zinc oxide (ZnO) Nanorods using hydrothermal (HTL) growth technique for pH sensor application. The highly crystallite of ZnO Nanorods was obtained by anneal the growth ZnO Nanorods in furnace at 200 °C for 2 hours. Besides that, XRD analysis shows the produced ZnO Nanorods belonged to the (002) plane. Furthermore, Scanning Electron Microscope (SEM) images confirm that the ZnO Nanorods with hexagonal-faceted structural were successfully produced by HTL growth technique. In addition, Ultraviolet–visible (UV-Vis) spectrophotometer analysis shows that the synthesized ZnO belongs to the wide band gap semiconductor material. The growing ZnO Nanorods were then subjected to electrical measurement with various pH levels. The outcome demonstrates that the current rises as the solution changes from acidic to alkaline. Overall, our study shows a relationship between the electrical as well as the structural characteristics of ZnO Nanorods at various pH levels.

Synthesis, characterization, and ameliorative effect of iron oxide nanoparticles on saline-stressed Zea mays

High soil salinity induces osmotic and ionic stress that threaten crop production worldwide and affect food security. This study evaluated the ameliorative effects of iron oxide nanoparticles on salinized Zea mays. Iron oxide nanoparticles were synthesized using an aqueous leaf extract of Diodella sarmentosa, and the results of the characterization using Fourier transform infrared (FTIR) spectroscopy, x-ray diffraction (XRD), energy-dispersive x-ray spectroscopy (EDX), transmission electron microscope (TEM), UV–visible spectrophotometer, and scanning electron microscope (SEM) revealed the presence of polydisperse spherical iron oxide nanoparticles (FeONPs) with a light absorption peak at 290 nm, and a size ranging from 3.03 nm to 87.04 nm. Daily foliar application of FeONPs on the salinized Zea mays for 10 days, significantly (p < 0.05) improved the plant’s photosynthetic pigments (total chlorophyl (175.71 %), chlorophyll a (256.34 %), chlorophyll b (77.01 %), carotenoid (39.36 %), root length (9.87 %), and antioxidant enzyme activities, compared to the untreated and bulk FeCl3·6H2O-treated controls. Since iron is known to promote photosynthetic pigment synthesis, the enhanced photosynthetic indices observed in the FeONPs-treated pot compared to the bulk FeCl3·6H2O-treated pot, may have resulted from the size-aided absorption of the FeONPs more than FeCl3·6H2O From the findings, it can be deduced that FeONPs can improve the growth and development of saline-stressed Zea mays by enhancing the activities of the antioxidant enzymes, while improving the photosynthetic pigments of the plant.

Green synthesis of carbon dots (CDs) and their use for selective determination of Pb2+

Carbon dots were synthesized from fenugreek seeds through a single step hydrothermal method. The method is simple, fast, pleasant to the environment and cheaper. The CDs were characterized by Fourier Transform Infrared (FTIR), UV–visible spectrophotometer, X-ray diffraction (XRD), High Resolution Transmission electron microscopy (HR-TEM), and fluorescence. The CDs obtained were extremely fluorescent. The fluorescent carbon dots exhibited excitation-dependent behavior with the maximum excitation at 372 nm. The interaction of CDs was studied with different selected cations Al3+, Ca2+, Cd2+, Cr3+, Co2+, Cu2+, Cu+, Fe2+, Fe3+, K+, Sn4+, Na+, Ni2+, Pb2+, Mn2+, Zn2+, Sr2+, (NH4)6Mo7O24, 4H2O, Cr6+, Sb3+, Ba2+, Li+, and Mg2+. None of the ions studied showed any effect on its fluorescence intensity except Pb2+ which decreased its intensity. A direct relationship was found between Pb2+ concentrations and quenching of CDs intensity. Detection limit (DL) and quantification limits (QL) were determined as three and ten times of the standard deviation of the blank for ten number of measurements. DL and QL were found in the order 9.345 μM and 31.15 μM respectively. This linear behavior between quenching and Pb2+ concentration is useful for analytical purpose.

Optimization of deposition time on structural, morphological, and optical properties of Cd1-xZnxS nanocrystalline thin films

In this work, Cd1-xZnxS nanocrystalline thin films have been synthesized over a glass substrate by a simple and cost-effective Chemical Bath Deposition (CBD) technique at various deposition time keeping other deposition parameters constant. The structural, morphological, and optical properties are studied by incorporating a range of characterization techniques, including X-ray diffraction (XRD), Field Emission Scanning Electron Microscopes (FESEM), Energy Dispersive X-rays (EDX), and UV–Visible spectrophotometers (UV–Vis). The films have been deposited at five different deposition time in the range from 30 mins to 150 mins to record the changes which address in depth the structural, morphological and optical properties. Empirical fitting equations have also been developed to obtain a more quantitative analysis of the effect of deposition time. The results obtained in this work are compared with some recent reported works for performance analysis of the buffer layer. The proposed buffer layer deposited at 30 mins not only attains all the desirable qualities required for maximum extraction of solar energy but also a low-cost and environment friendly option, making it a potential candidate for solar cell and optoelectronic applications.

Integration of orange peel derived carbon quantum dots with TiO2 for enhanced photocatalytic degradation of brilliant green dye

Brilliant green (BG) dye is a non-biodegradable, highly venomous and coloured pigment. BG dye possesses remarkably high visibility even at small concentration that causes diarrhea and abdominal pain in humans when being ingested. In addition, it is harmful to living organisms and polluting aquatic environments. Hence, eliminating BG dye from contaminated water is an urgent need. In this report, a photocatalyst encompasses hydrothermally prepared titanium dioxide (TiO2) integrated with orange peel derived oxygenated carbon quantum dots (O-CQDs) was developed for effective removal of BG dye. The O-CQDs were prepared using a single step eco-friendly hydrothermal process and an intense green fluorescence was observed upon exposing the O-CQDs to far UV light irradiation (254 nm). The formation of TiO2/O-CQDs nanohybrid was confirmed through UV–Visible spectrophotometer, X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM) and X-ray photoelectron spectroscopy (XPS) analyses. A random distribution of spherical shaped O-CQDs on the surface of TiO2 was clearly observed in FESEM images. The carboxyl groups present in O-CQDs not only increased interlayer spacing but also led to the attachment of TiO2 effectively. The TiO2/O-CQDs nanohybrid showed 94.70 % efficiency towards photocatalytic degradation of BG dye under UV light irradiation that was ∼20 % higher than the efficiency of pristine TiO2 photocatalyst. The presence of O-CQDs in the TiO2/O-CQDs nanohybrid boosted the photocatalytic degradation efficiency by enhancing UV light absorption and suppressing photo-generated electron–hole recombination. The integration of agricultural waste derived carbon with TiO2 by a facile synthesis method paves a way for large scale synthesis of TiO2/O-CQDs nanohybrid, which is anticipated to broaden its application potential in environmental remediation through photocatalytic degradation of organic compounds.

Effect of spin coating speeds on electrical and optical characteristic of perovskite SrTiO3 thin films prepared by sol-gel method

The perovskite strontium titanate (SrTiO3/STO) was prepared by the sol-gel process, and the STO thin film was deposited onto a glass substrate by the spin coating method. Effect of different spin coating speeds on the thickness, structural, optical, and electrical properties of the STO thin films was discussed. Five STO films with various spin coating parameters of 2000, 4000, 6000, 8000, and 10000 RPM were prepared. Thickness profilometer tests have shown that the thickness of the STO film changes from 802 nm at 10000 RPM to 1321 nm at 2000 RPM spin coating speed. The prepared STO films morphology was examined by scanning electron microscope. X-ray diffraction measurements have shown that crystalline STO films have been produced with a cubic perovskite structure. The optical properties of the prepared STO films were investigated using an ultraviolet visible spectrophotometer, and the results indicated that the STO film at 8000 and 4000 RPM spin speed show the lowest and the maximum optical band gap (2.83 and 2.90 eV, respectively). All STO films have absorption coefficient values higher than 103 cm−1. The prepared STO thin films had a refractive index between 2.40 and 2.42. The electrical characteristics of the prepared STO films were investigated using the four-point probe method, and it was found that as the spin coating speed increased from 2000 to 8000 RPM, the resistivity of the STO films reduced from 6.629∗1010 to 3.009∗1010 Ω. Moreover, the STO film at 8000 RPM spin speed has the best electrical conductivity (3.301∗10−5 S m−1).

Carica papaya L. Latex Mediated Green Synthesis of Zno Nanoparticles for its Antimicrobial Activity

Zinc oxide nanoparticles have gained potential recognition because of their distinctive characteristics and wide utilizatrion in various fields. Therefore, development of novel biological techniques is significant for the biosynthesis of ZnO nanoparticles using the latex of Carica papaya L. Plant latex is a natural product produced by a number of plant species which are used by different tribal communities in India as a folk medicinal treatment on natural wounds or cuts. Plant latex has a huge demand as herbal products in an aspect of clinical, therapeutical and also in agricultural sectors. Natural latex is composed of different important biomolecules like, tannins, flavonoids, glycosides, sterols, saponins etc. These different active chemical constituents have versatile medicinal activities against different pathogens such as bacteria, fungi, viruses and protozoans etc. This study reports on the biosynthesis of ZnO nanoparticles (Zn NPs)using latex of C. papaya as an effective reducing agent. Green synthesis of nanoparticles has advantageous over conventional methodsbecause it does not require the use of toxic chemicals and therefore environmentally sustainable. The elemental composition of C. papaya latex was also analysed using X-ray Fluorescence (XRF) technique. Properties of synthesized ZnO NPs were characterized using various methods such as ultra violet visible spectrophotometer (UV-Vis), scanning electron microscopy and Fourier transform infrared spectroscopy. Green synthesized ZnO nanoparticles also assessed for its antimicrobial activity against selected bacterial and fungal species.

Effect of Sugar on Anthocyanins in Rosella Kombucha Drink

Rosella kombucha is a fermented drink with a high antioxidant content and is known to be a solution that can neutralize free radicals and prevent oxidative stress. The ingredients in rosella kombucha drinks are anthocyanins, flavonoids, vitamin C, and polyphenols. Anthocyanin is a natural color pigment produced by plants. Anthocyanin is an antioxidant that is beneficial for the body. The fermentation process for the rosella kombucha drink was carried out for 14 days. This research aimed to determine the effect of sugar concentration on anthocyanin levels in rosella (Hibiscus sabdariffa L.) kombucha drinks. The method used in this research is quantitative experimental with a completely randomized research design (RAL) with 3 samples and 3 repetitions. The independent variable in this study is sugar concentration, while the dependent variable is anthocyanin content. The subject of this research is sugar concentration, with concentrations of 15%, 25%, and 35%. Anthocyanin levels were measured using a visible spectrophotometer using a wavelength of 700 nm. Data analysis used in this research used the Shapiro-Wilk test and the One Way ANOVA test. The results of the data analysis show that the highest average is found in the F3 sample at 38.743900 ppm. The results of data analysis using the One Way ANOVA test showed a p-value &lt;0.05, which means it has a real influence. The lowest pH value was found in sample F3, namely 2. The low pH helped stabilize the anthocyanin levels in the Rosella kombucha drink. The results showed that the sugar concentration used to make rosella kombucha drinks in all samples had a significant influence on anthocyanin levels (p&lt;0.05).

Antibacterial activity of biogenic and chemically synthesized silver nanoparticles and its application in wastewater treatment

The present work reports the synthesis of silver nanoparticles (Ag NPs) by chemical as well as biological approaches. Ag NPs have been synthesized using different plant extracts such as Aloe vera, Syzygium aromaticum (clove), Musa (banana leaf), and Citrus X Sinensis (orange peel). The effect of various reducing agents has been examined on the shape and morphology of the synthesized Ag NPs. The synthesized Ag NPs have been characterized using UV–visible spectrophotometer, Dynamic Light Scattering (DLS), and Transmission Electron Microscopy (TEM). The average size of the synthesized Ag NPs has been confirmed by DLS characterization as 64 ± 11 nm, 106 ± 8 nm, 500 ± 14 nm, 281 ± 9 nm and 105 ± 7 nm, respectively. when synthesized using Aloe vera, Syzygium aromaticum, Musa, Citrus X Sinensis, and trisodium citrate (TSC), respectively. The synthesized Ag NPs have been used for screening antibacterial activity against Escherichia coli, Staphylococcus aureus and Bacillus subtilis. The synthesized Ag NPs have also been evaluated for their bactericidal property against wastewater from polluted rivers and other water sources and have been found appropriate for use in bacteriological and wastewater treatment.

Health Risk Assessment of Exposure to Iron in Gravity Feed System Water among Indigenous People

This study aims to determine the health risk exposure of iron level in drinking water from gravity feed system among residents at Sungai Mas village, Sungai Lembing, Kuantan Pahang. A cross-sectional research was carried out based on inclusion and exclusion criteria. The purposive sampling method was used to select respondents of Jakun and Semaq Beri tribe. This research had two parts;questionnaire,as well aswater sample collection and analysis. The iron level was determined using Hanna Instruments HI801-02 iris Visible Spectrophotometer, while pH level was determined using EUTECHC Cyberscan pH 310 Series Meter. Median and IQR of iron were 0.080 and 0.030 mg/L, respectively.There was no relationship between iron and pH levels of drinking water samples in the study area. There was no significant difference between iron levels in drinking water and the National Standard for Drinking Water Quality, and the value ranged between 0.030-0.550 mg/L. There was no health risk of iron exposure among respondents. The HQ was &lt;1. Generally, drinking water containing iron had no adverse health effects. The iron in drinking water in this study was not influenced. So there are no carcinogenic effects on the community in Sungai Mas Village, Sungai Lembing.

In-Vitro Evaluation of Antioxidant Potential of Colocasia esculenta Corms

Introduction: Colocasia esculenta Linn (family: Araceae; synonym: Arum esculentum Linn; Taro) is one of the most important tubers crops worldwide and has been employed for medicinal applications for a significant period. Traditionally, in Indian and Chinese medicine, taro is utilized for many years for medicinal applications such as hypoglycaemic, antifungal, antimicrobial, hepatoprotective, and nervine tonic Taking into consideration the traditional claims, C. esculenta has the potential to be a useful for antioxidant activity. With this perspective in mind, the current research aimed to investigate the antioxidant potential of C. esculenta corms. Method: In vitro antioxidant activity aqueous extract of C. esculenta corms was studied by DPPH method. Ascorbic acid was used as a reference standard. The absorbance of various concentrations of corm extract and ascorbic acid were measured by using UV–Visible Spectrophotometer and the percent radical scavenging activity (% RSA) of the DPPH free radical was measured. Results: The Radical scavenging activity of corm extract of C. esculenta at 400μg/mL was found to be 80.33% at absorbance 0.142. The IC50 value of C. esculenta was found to be 120.16μg/mL which was calculated by using y = 0.0952x+38.56 equation. The Radical scavenging activity of Ascorbic acid at 400μg/ml was found to be 87.67% at absorbance 0.089. The IC50 value of Ascorbic acidwas found to be 28.05μg/mL which was calculated by using y = 0.091x+47.43 equation. Conclusion: Our study indicates that the corm extract has the potential as an antioxidant agent, possibly inhibiting DPPH, when compared with standard ascorbic acid. However, the chemical constituents present in the extract such as saponins, steroids, carbohydrates, glycosides, tannins, flavonoids and proteins may be responsible for such activity.

Effects of Spray Adjuvants on Droplet Deposition Characteristics in Litchi Trees under UAV Spraying Operations

In the last decade, unmanned aerial vehicles (UAVs) for plant protection have rapidly developed worldwide as a new method for pesticide application, especially in China and other Asian countries. To improve the deposition quality in UAV applications, adding appropriate types of spray adjuvants into pesticide solutions is one of the most effective ways to facilitate droplet deposition and control efficacy. At present, research on spray adjuvants for UAVs are mainly based on droplet drift and laboratory tests. Few studies have been conducted on the physicochemical properties of spray adjuvants and the effects of droplet deposition characteristics. To explore the properties of four different kinds of spray adjuvants (Mai Fei, Bei Datong, G-2801, and Agrospred 910) and the deposition characteristics of spray adjuvants on litchi leaves, an automatic surface tension meter, a contact angle measuring device, an ultraviolet visible spectrophotometer, and a DJI AGRAS T30 plant protection UAV was used to measure the surface tension, contact angle, and droplet deposition characteristics on litchi under UAV spraying operations. The results showed that the addition of spray adjuvants could significantly reduce the surface tension of the solution. The surface tension value of the solution after adding the spray additives was reduced by 53.1–68.9% compared with the control solution. Among them, the Agrospred 910 spray adjuvant had the best effect on reducing the surface tension of the solution. The contact angle of the control solution on the litchi leaves varied from 80.15° to 72.76°. With the increase in time, the contact angle of the spray adjuvant solution gradually decreased, the Agrospred 910 spray adjuvant had the best effect, and the contact angle decreased from 40.44° to 20.23° after the droplets fell on the litchi leaves for 60 s. The adjuvant solutions increased the droplet size, but the uniformity of the droplet size decreased. The Dv0.5 of different spray solutions ranged from 97.3 to 117.8 μm, which belonged to the fine or very fine droplets, and the Dv0.5 of adjuvants solutions were significantly greater than that of the control solution. The RSs of adjuvant solutions were very similar and ranged from 0.92 to 0.96, all of which were significantly greater than the result of the control solution (0.57). Compared with the deposition of the control solution, the Mai Fei, Bei Datong, and G-2801 solutions clearly increased spray deposition, with total depositions of 0.776, 0.705, and 0.721 μL/cm2, which are all greater than the total deposition of the control solution of 0.645 μL/cm2. The addition of tank-mixed adjuvants could effectively increase the uniformity of the spray deposition, and all the average CVs of adjuvant solutions were lower than 96.86%. On the whole, Mai Fei performed best in increasing the spray deposition and promoting penetration, followed by Bei Datong and G-2801. Meanwhile, the test can also provide a reference for improving the utilization rate of UAV pesticide applications.

Evaluation of antioxidant, catalytic and antidiabetic activity of Phaseolus vulgaris (French green bean) mediated nickel oxide and copper doped nickel oxide bimetallic nanoparticles

In this study, nickel oxide nanoparticles (NPs) and copper doped NiO bimetallic nanoparticles (Cu@NiO BMNPs) were synthesized using Phaseolus vulgaris extracts as reducing and stabilizing agents by sol gel methods. The chemical and physical properties of synthesized NiO NPs and Cu@NiO BMNPs were confirmed by various techniques, like UV Visible spectrophotometer (UV–Vis), Fourier transform infrared spectroscopy (FTIR), Scanning Electron Microscope (SEM), Energy Dispersive X-ray (EDX), Transmission Electron Microscope (TEM) and X-ray diffraction (XRD) analysis. The optical properties of both NPs observed by UV–Vis analysis with well-defined peak and band gap value 3.2 eV & 2.62 eV. FTIR analysis confirmed the presence of functional group of NPs with fruits extract. The morphology of NPs was confirmed by SEM and TEM analysis as polygonal, rod and spherical shape. The elements present in NPs were confirmed by EDX analysis. The crystalline size calculated based on the XRD analysis was 49.78 nm and 53.66 nm for NiO and Cu@ NiO NPs respectively which were found to be slightly smaller than particle size determined from SEM and TEM micrograph. Antioxidant activity of NPs was examined using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging radicals, Catalytic activities were screened by the degradation of Methylene blue (MB) and by the inhibition of alpha-amylase enzyme, antidiabetic activity of NPs were evaluated using acarbose as standard drug. The Cu@NiO BMNPs showed 77.60 % antioxidant, 76.98 % photocatalytic and 88.86 % antidiabetic activity, which were found to be more as compared to NiO NPs. The NiO and Cu@NiO BMNPs were synthesized for the first-time using P. vulgaris extracts. This study clearly showed that P. vulgaris extracts mediated mono- and bimetallic NPs were more stable and biocompatible than their respective bulk particles.