Suphiya Khan

Copper/zinc bimetal nanoparticles-dispersed carbon nanofibers: A novel potential antibiotic material

Copper (Cu) and zinc (Zn) nanoparticles (NPs) were asymmetrically distributed in carbon nanofibers (CNFs) grown on an activated carbon fiber (ACF) substrate by chemical vapor deposition (CVD). The CVD conditions were chosen such that the Cu NPs moved along with the CNFs during tip-growth, while the Zn NPs remained adhered at the ACF. The bimetal-ACF/CNF composite material was characterized by the metal NP release profiles, in-vitro hemolytic and antibacterial activities, and bacterial cellular disruption and adhesion assay. The synergetic effects of the bimetal NPs distributed in the ACFs/CNFs resulted from the relatively slower release of the Cu NPs located at the tip of the CNFs and faster release of the Zn NPs dispersed in the ACF. The Cu/Zn-grown ACFs/CNFs inhibited the growth of the Gram negative Escherichia coli, Gram positive Staphylococcus aureus, and Methicillin resistance Staphylococcus aureus bacterial strains, with superior efficiency (instant and prolonged inhibition) than the Cu or Zn single metal-grown ACFs/CNFs. The prepared bimetal-carbon composite material in this study has potential to be used in different biomedical applications such as wound healing and antibiotic wound dressing.

Genetic differentiation and diversity analysis of medicinal tree Syzygium cumini (Myrtaceae) from ecologically different regions of India

This study represents the agro-ecological zone wise surveys of molecular variation of important medicinal tree Syzygium cumini Linn. (Jamun) which is native to India. It is used world wide in treatment of diabetes. Despite of its diverse medicinal properties no molecular data is available about the pattern of variation in its natural range. Populations of S. cumini in India are located in different habitats which differ from each other with regard to ecological factors. In this study, random amplified polymorphic DNA (RAPD) markers were used to detect inter and intra levels of genetic variations of sixteen S. cumini genotypes collected from three major agro-ecological zones of India. A total of 220 amplification products were scored of which 87.50 % were polymorphic. The level of polymorphism ranged from 47.69 % to 74.87 % polymorphic bands per population and was correlated with population size. Different measures of diversity: Shannon’s index of phenotypic diversity (I) = 0.451 ± 0.230; Nei’s genetic diversity (h) = 0.300 ± 0.172; effective number of alleles per locus (Ne) = 1.51 ± 0.347; total species diversity (Hsp) = 0.315 ± 0.031 and within population diversity (Hpop) = 0.158 ± 0.104 showed high genetic diversity at species level. Coefficient of genetic differentiation (Gst =0.498; Nm = 0.503) revealed significant genetic differentiation among the populations. Most of the genetic variations are contained among the populations. The results of cluster analysis and principal component analysis (PCA) give only little evidence for an ecotypic differentiation of S. cumini populations. Present genetic structure of population suggests ex situ conservation in seed banks in which seeds from at least five populations need to collected and conserved. Secondly, our study provides practical information to herbal drugs manufactures who use Jamun as a raw material.

Highly effective Cu/Zn-carbon micro/nanofiber-polymer nanocomposite-based wound dressing biomaterial against the P. aeruginosa multi- and extensively drug-resistant strains

Pseudomonas aeruginosa (P. aeruginosa) is the most prevalent bacteria in the infections caused by burn, surgery, and traumatic injuries. Emergence of the P. aeruginosa bacterial resistance against various clinical drugs for wound treatment is the major concern nowadays. The present study describes the synthesis of the polyvinyl alcohol (PVA) and cellulose acetate phthalate (CAP) polymeric composite film (~0.2mm thickness) reinforced with the Cu/Zn bimetal-dispersed activated carbon micro/nanofiber (ACF/CNF), as a wound dressing material. The focus is on determining the efficacy of the prepared biomaterial against the multi and extensively drug-resistant P. aeruginosa strains isolated from the burning, surgical, and traumatic injury-wounds. The primary synthesis steps for the biomaterial include the mixing of a blend of CAP powder and the asymmetrically distributed Cu/Zn bimetals in ACF/CNF, into the polymerization reaction mixture of PVA. Biochemical tests showed that the prepared composite material significantly enhanced the in-vitro blood clotting rate, platelet aggregation, and macrophage cell proliferation, indicating the suitability of the material as a fast wound healer. The antibacterial tests performed against the P. aeruginosa strains showed that the material effectively suppressed the bacterial growth, with the bimetal nanoparticles dispersed in the material serving as an antibacterial agent. The PVA/CAP polymer composite served as an encapsulating agent providing a slow release of the nanoparticles, besides increasing the hemostatic properties of the biomaterial. The ACF/CNF served as a support to the dispersed bimetal nanoparticles, which also provided a mechanical and thermal stability to the material. Experimentally demonstrated to be biocompatible, the prepared metal-carbon-polymer nanocomposite in this study is an effective dressing material for the P. aeruginosa-infected wounds.

Defluoridation technology for drinking water and tea by green synthesized Fe 3 O 4 /Al 2 O 3 nanoparticles coated polyurethane foams for rural communities

Fluoride (F) contaminated ground water poses a serious public health concern to rural population with unaffordable purification technologies. Therefore, development of a cost-effective, portable, environment and user-friendly defluoridation technique is imperative. In the present study, we report on the development of a green and cost-effective method that utilizes Fe3O4 and Al2O3 nanoparticles (NPs) that were synthesized using jojoba defatted meal. These NPs were impregnated on to polyurethane foam (PUF) and made into tea infusion bags. The Al2O3 NPs-PUF displayed a higher water defluoridation capacity of 43.47 mg g−1 of F as compared to 34.48 mg g−1 of F with Fe3O4 NPs-PUF. The synthesized Al2O3-PUF infusion bags removed the F that was under the permissible limit of 1.5 mg L−1. The sorption experiments were conducted to verify the effect of different parameters such as pH, contact time, size of PUF and initial F concentration. The different properties of adsorbent were characterized using a combination of FESEM, EDX, XRD and FTIR techniques, respectively. The calculated total cost per NPs-PUF pouch developed is as low as US

Carbon nanofibers as a micronutrient carrier in plants: efficient translocation and controlled release of Cu nanoparticles

0.05, which makes the technology most suitable for rural communities. This paper will be beneficial for researchers working toward further improvement in water purification technologies.

Heavy Metal ATPase ( HMA2 , HMA3 , and HMA4 ) Genes in Hyperaccumulation Mechanism of Heavy Metals

An aqueous colloidal dispersion (∼230 nm average size) of the copper (Cu) nanoparticle (NP)-grown carbon nanofibers (CNFs) was used as a stimulant for crop yields. The Cu-CNFs (average diameter = 95 nm), separately prepared on an activated carbon microfiber substrate using chemical vapor deposition, were dispersed in Cicer arietinum seed-containing water. The CNFs served as a carrier for the Cu micronutrient, with a controlled release of the Cu NPs. The CNFs also served as a growth stimulant by increasing the water uptake capacity of the plants. The scanning electron microscopy images, elemental (Cu/C) mapping, and atomic absorption spectrometry data corroborated the effective translocation of the Cu-CNFs from the root to the shoot of the plants. The water uptake capacity, germination rate, shoot and root lengths, and chlorophyll and protein contents significantly increased in the plants using the Cu-CNFs. This is the first study showing the use of the Cu-CNFs as a carrier of micronutrients in plants, with an effective translocation ability.

Role of Phytochelatins (PCs), Metallothioneins (MTs), and Heavy Metal ATPase (HMA) Genes in Heavy Metal Tolerance

Abstract Heavy metals are the most important pollutants, which are nonbiodegradable and increasingly accumulate in the environment. Phytoremediation can be defined as the use of plants for the extraction, immobilization, containment, or degradation of contaminants. It provides an ecologically, environmentally sound, and safe method for restoration and remediation of contaminated land. Plant species vary in their capacity of hyperaccumulation of heavy metals. The present work reviews the current findings on the molecular mechanism involved in heavy metal tolerance, which is a valuable tool for the phytoremediation. The heavy metal tolerance genes help in the hyper accumulation trait of a plant. Heavy metal transporter ATPases genes help in the refluxing of heavy metal ions from the cytosol, either into the apoplast, the vacuole, or other organelles, and help in the hyperaccumulation of metal. Understanding the signaling mechanism of transporter genes will be an important tool to understand the genetics of hyperaccumulation.

Effect of Fe3O4 NPs application on fluoride (F) accumulation efficiency of Prosopis juliflora

Phytoremediation has been approved an economical technology for the cleanup of environmental contaminants and biomass production. Germplasm of hyperaccumulators is the backbone of this technology. Therefore, understanding the genetics of hyperaccumulation is an important tool for the enhancement of hyperaccumulation efficiency. Phytochelatins (PCs) and metallothioneins (MTs) and heavy metal ATPase (HMA) genes play a crucial role in signaling, uptake, detoxification, and accumulation of metal. Their combined role enhances the hyperaccumulation efficiency. This chapter highlights the role of these genes, their mechanism of action, their structure, and their applications in the transgenic approach of hyperaccumulation. Further, it also highlights the role of uptake and detoxification of metals by cellular mechanisms which facilitate the phytoremediation of heavy metals from contaminated areas.

Synthesis and Applications of Nanofungicides: A Next-Generation Fungicide

Fluoride (F) pollution is a major worldwide problem affecting approximately 200 million people. Hyperaccumulator plant Prosopis juliflora has been used for the removal of F from contaminated soils; however its low F accumulation efficiency and low biomass limits the phytoremediation efficiency. Present study deals with enhancement of F uptake efficiency of plant P. juliflora through iron oxide nanoparticles (Fe3O4 NPs) application for remediation of agricultural soils. For the study, Fe3O4 NPs were synthesized through green route using waste jojoba leaves. The application of Fe3O4 NPs significantly increased the shoot and root length of plant P. juliflora. Fe3O4 NPs treatment also promoted the F accumulation in shoot and root tissues upto 28.43 and 34.64 mg kg-1, respectively. Microscopic (FESEM and light microscopic) and EDX spectrum analysis of plant tissues confirmed the accumulation and translocation of Fe3O4 NPs and F in plant tissues This nano-phytoremediation approach could be a better option for F remediation for agricultural and commercial purpose.

Organ-wise accumulation of fluoride in Prosopis juliflora and its potential for phytoremediation of fluoride contaminated soil

With the increasing population, the pressure of enhancing food production and management of fungal diseases of food crops and fruits in agriculture sector needs urgent concern. Nanofungicides due to their vast physiochemical and functionalization properties could be easily applied for plant disease management. This chapter covers the different types of nanofungicide synthesis with mechanism. The chapter also gives comprehensive idea about fungal mycotoxins and its harmful effects on agricultural sector. Apart from it, this chapter also highlights the effects of nanoparticles (NPs) on mycotoxins produced by fungi and its mechanism of action.