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It has been noticed that Saraca asoca (Roxb. de Wilde) populations are drastically declining in the wild. Conserving such populations is crucial because of the numerous ecological, cultural, and economic values. The purpose of our study was to determine if germination and seedling growth could be improved for globally vulnerable Ashoka populations. The study analyzed the effect of various hydro, mechanical, and chemical pre-sowing treatments on the germination and one-year growth of Ashoka seedlings. Our results demonstrated that mechanical (exposing the seed cotyledons) and soaking of seeds in hot water treatments (60 °C) were better than all other water- and chemical-based pre-sowing treatments used in the study of enhancing germination. Nevertheless, chemical treatments were better for the growth and survival of the seedlings. This methodology offers to restore the scattered populations of Ashoka that are facing the risk of extinction in the wild while successfully meeting the commercial demand for this medicinal tree.

Nanotechnology offers promising solutions for climate-resilient agriculture, countering challenges like stagnant yields, emerging pests, and environmental stresses posed by changing global climates. Nanoparticles (NPs) possess unique properties and biological interactions. Metal-based NPs have been tailored for functions like antimicrobial activity, insecticidal properties, and weed inhibition and hold promise for combating biotic stresses and offer the potential for plant pest control, disease detection and management, stress resilience, weed control, and enhancing biomass and crop yield. Metallic NPs repel pests, exhibit larvicidal and ovicidal properties, combat plant pathogens, deliver agrochemicals precisely, and prevent weed growth, eventually boosting agricultural productivity. Numerous NP-based metal and metal oxide nanoproducts, including nanocarriers for nanofertilizers and nanopesticides, nanobiosensors for early pathogen detection, and nanoclays for weed control have flooded the market. Though, mechanistic details of NPs action in mitigating biotic stresses are poorly accounted for, metallic NPs combat pathogens by incurring DNA damage and generating reactive oxygen species (ROS). They fortify plant defense by activation of regulatory factors, induction of antioxidant systems, activation of stress-related genes, and modulation of the metabolic pathways to enhance plant growth. Nevertheless, nanotechnology in agriculture is in its infancy yet, necessitating further research to comprehend its merits and demerits. The potential toxicological effects of NPs underscore the importance of optimizing their dosage to maximize benefits while minimizing negative impacts. Further, redressal of regulatory and safety concerns associated with NPs application in agriculture is essential to ensure their safe and sustainable usage. Clear universal guidelines and standardized testing protocols need to be mandated to uphold their global implementation to transform agriculture.

Light quality (spectral arrangement) and quantity (photoperiod and intensity) influence plant growth and metabolism and also interact with several factors including environmental parameters in defining the plant behavior. The Light Emitting Diode (LED) lights are extensively utilized in the cultivation of several plant species, especially horticultural plants due to their lower power consumption and higher luminous efficiency compared to the conventional fluorescent lights. The aim of this review paper is to examine the potential of LED technology as it relates to plant lighting in greenhouses and other horticultural environments. It also desires to give an in-depth study of the advantages of LED lighting on plant development, yield, the production of secondary metabolites, and defense mechanisms. Horticultural lighting might undergo a revolution because LEDs are used in solid-state lighting, which would be a tremendous advancement after decades of research. LEDs may be used in a variety of horticulture lighting applications, such as tissue culture lighting, controlled environment research lighting, supplementary lighting, and photoperiod lighting for greenhouses. The primary impacts of light colors on plant performance are shown by the spectrum effects of LEDs as an independent source of light, together with the diverse sensitivity of many plant species and alternatives. LED light influences performance of enzyme, gene expression, cell wall formation, plant defense and postharvest quality. The spectrum reactions are mediated by the ambient lighting in a greenhouse, which also indicates a strong relationship between the additional supplementary lighting and changing environmental factors. LEDs are growing further to become cost-effective for even large-scale horticulture lighting applications as light output increases and device expenditures decrease.

ABSTRACTThe allelopathic effect of Callistemon viminalis’s leaf extracts on seed germination and growth of Triticum aestivum and Cicer arietinum, as well as associated weeds (Anagallis arvensis, Poa annua, Lepidium didymium, and Vicia sativa), was studied. Different concentrations (2–10%) of aqueous extracts were used, and physiological parameters were measured. Higher concentrations (6–10%) significantly inhibited the germination and growth of wheat and chickpea. In pot assay, the extract did not affect shoot length, dry plant mass, chlorophyll, carotenoid, proline, protein content, stomatal conductance, photosynthetic and transpiration rate, and antioxidant enzymes in crop and various parameters of soil properties in comparison to the control. Both crops grew significantly at lower concentrations. This study suggests that extract of C. viminalis can inhibit the growth of A. arvensis and V. sativa without affecting germination, photosynthetic and biochemical properties of C. arietinum and T. aestivum, and soil properties, making it a potential candidate for bioherbicide development.

Abstract Wild and underutilized plants bearing fruits widely grow throughout the northern Himalayas, including Himachal Pradesh, Jammu and Kashmir, Ladakh, and Uttarakhand states of India. The fruits of these plants have the potential for rural development in Northern Himalayas by developing more commercial products. Ficus auriculata, Rubus ellipticus, Myrica esculenta, Ficus palmata, Pyracantha crenulate, Prunus armeniaca, Berberis asiatiica, Pyrus pashia, Rubus niveus, Carissa spinarum, Cordia dichotoma, Flacourtia indica, Malus sikkimensis, Olea ferruginea, Elaeagnus latifolia, Corylus jacquemontii, and Pinus gerardiana are some examples of the plant species. Local people mainly consume the fruits of these plant species and a few of them are used for different processed food items such as jam, jelly, juice, squash, and sauce on a small scale. Therefore, fruits of wild and underutilized plants have potential nutritional values. They are widely used as sources of protein, fat, carbohydrate, macronutrients, and micronutrients. These fruits also contain multipurpose and diversified classes of phytochemical compounds such as flavonoids, tannins, terpenoids, saponins, glycosides, and alkaloids, which are applied to treat various human and livestock health ailments. The extracts of underutilized fruits are widely applied to treat cold, fever, fertility disorders, diabetes, and skin diseases. Their phytochemical compounds also demonstrated antipyretic, analgesic, anti-inflammatory, anticancer, antimicrobial, antiplasmodial, and antinociceptive activities. Thus, this review highlights the current research status about the nutritional profiling, chemical composition, and utilization of these valuable fruits effectively/adequately to develop new food and pharmaceutical products. Graphical Abstract

Plant-derived bioactive products and their structural diversity have made a significant contribution to various pharmacological activities including cancer and other infectious diseases. Application of natural products and their derivatives in multi-faceted anti-cancer effects and advanced disease management is extensively under consideration at the level of primary, secondary and tertiary care prevention. Hemidesmus indicus (L.) R. Br. ex Schult belongs to the family Apocynaceae and extensively used in poly-herbal preparations and several biological activities. The connection between chronic inflammation and cancer has drawn considerable interest and acceptance. The activation of genes that regulate cell signaling pathways associated with inflammation can take control over various aspects of the disease process. Among the various signaling pathways (STAT-3, HIF-1, NF-κB, IL-1, Cox-2, TNF-α, and oncogenic Kinase (P13k, IKK, IRAK1/4, JAK, MARK/ERK, and Syk/Src) are essential for establishing a connection between inflammation and cancer. Due to this theoretical basis, the inflammatory response to cancer has emerged as the center of attention for novel preventive and therapeutic approaches. To reduce inflammation, immunomodulatory medications are often used in cancer therapy. Although considering the adverse reactions associated with synthetic immunomodulatory substances and cytotoxic cancer drugs, it is essential to explore the development of innovative anti-inflammatory agents to enhance cancer treatment. Several reports suggest that bioactive phytochemicals obtained from H. indicus demonstrate anti-inflammatory properties in the context of cancer. There is a need for further investigation into the cellular processes underlying anti-inflammatory effects of H. indicus, in order to develop a comprehensive understanding of its potential in cancer treatment. However, many phytochemicals need to be further explored for their application in biomedical treatments. Moreover, studies regarding molecular mechanisms and mode of action, effective and safe doses of H. indicus, and its phytochemicals for the treatment of inflammation associated with cancer and other pharmacological activities needs to be explored. Overall, the present review describes and concludes the role of H. indicus to investigate the mechanism and to improve the cancer prevention. In addition, safety, toxicity and clinical evaluation is also discussed.

A rapid surge in world population leads to an increase in worldwide demand for agricultural products. Nanotechnology and its applications in agriculture have appeared as a boon to civilization with enormous potential in transforming conventional farming practices into redefined farming activities. Low-cost portable nanobiosensors are the most effective diagnostic tool for the rapid on-site assessment of plant and soil health including plant biotic and abiotic stress level, nutritional status, presence of hazardous chemicals in soil, etc. to maintain proper farming and crop productivity. Nanobiosensors detect physiological signals and convert them into standardized detectable signals. In order to achieve a reliable sensing analysis, nanoparticles can aid in signal amplification and sensor sensitivity by lowering the detection limit. The high selectivity and sensitivity of nanobiosensors enable early detection and management of targeted abnormalities. This study identifies the types of nanobiosensors according to the target application in agriculture sector.

Abstract Conventional agriculture solely depends upon highly chemical compounds that have negatively ill-affected the health of every living being and the entire ecosystem. Thus, the smart delivery of desired components in a sustainable manner to crop plants is the primary need to maintain soil health in the upcoming years. The premature loss of growth-promoting ingredients and their extended degradation in the soil increases the demand for reliable novel techniques. In this regard, nanotechnology has offered to revolutionize the agrotechnological area that has the imminent potential over conventional agriculture and helps to reform resilient cropping systems withholding prominent food security for the ever-growing world population. Further, in-depth investigation on plant-nanoparticles interactions creates new avenues toward crop improvement via enhanced crop yield, disease resistance, and efficient nutrient utilization. The incorporation of nanomaterial with smart agrochemical activities and establishing a new framework relevant to enhance efficacy ultimately help to address the social acceptance, potential hazards, and management issues in the future. Here, we highlight the role of nanomaterial or nanocomposite as a sustainable as well stable alternative in crop protection and production. Additionally, the information on the controlled released system, role in interaction with soil and microbiome, the promising role of nanocomposite as nanopesticide, nanoherbicide, nanofertilizer, and their limitations in agrochemical activities are discussed in the present review.

The objective of this study was to determine the effects of Murraya koenigii (curry leaf) aqueous extract on the seed germination and growth of two crops and their associated weeds (Anagallis arvensis, Poa annua, Lepidium didymum, and Vicia sativa). Wheat (Triticum aestivum) and Chickpea (Cicer arietinum) seeds were soaked in solutions containing 2, 4, 6, 8, and 10% concentrations of aqueous extracts of M. koenigii leaves, while distilled water was used as a control. Higher concentrations of the extract significantly increased the percentage of germination inhibition and decreased the radicle length and plumule length of both crops compared to the control. It was interesting to find that the pot-based experiment had no influence on the shoot length, plant dry mass, chlorophyll, carotenoid, proline, or protein content, stomatal conductance, or photosynthetic and transpiration rate in either crop. Similarly, in comparison to the control, the activity of antioxidant enzymes (peroxidase (PER), superoxide dismutase (SOD), and catalase (CAT)) had no significant influence. Soil physiochemical parameters and weed shoot growth were also investigated. In a Petri plate experiment, 6, 8, and 10% concentrations inhibited germination of both crops. In comparison, in the pot experiment, the growth of both crops was significant at lower concentrations, and 1% aqueous extract of M. koenigii was reported to be lethal to weeds without affecting the soil physiochemical properties. Based on the results of this study, it can be inferred that the reduced germination rate of the tested species after treatment with the extract could be attributed to damage caused by the extracts to the membrane system of the seed. This study concluded that an aqueous leaf extract of M. koenigii can inhibit the growth of weeds without affecting the germination, growth, photosynthetic, and biochemical properties of C. arietinum and T. aestivum or the physiochemical properties of soil; thus, it may be a potential candidate for the development of new bioherbicides.

Abstract Previous decades have witnessed a lot of challenges that have provoked a dire need of ensuring global food security. The process of augmenting food production has made the agricultural ecosystems to face a lot of challenges like the persistence of residual particles of different pesticides, accretion of heavy metals, and contamination with toxic elemental particles which have negatively influenced the agricultural environment. The entry of such toxic elements into the human body via agricultural products engenders numerous health effects such as nerve and bone marrow disorders, metabolic disorders, infertility, disruption of biological functions at the cellular level, and respiratory and immunological diseases. The exigency for monitoring the agroecosystems can be appreciated by contemplating the reported 220,000 annual deaths due to toxic effects of residual pesticidal particles. The present practices employed for monitoring agroecosystems rely on techniques like gas chromatography, high-performance liquid chromatography, mass spectroscopy, etc. which have multiple constraints, being expensive, tedious with cumbersome protocol, demanding sophisticated appliances along with skilled personnel. The past couple of decades have witnessed a great expansion of the science of nanotechnology and this development has largely facilitated the development of modest, quick, and economically viable bio and nanosensors for detecting different entities contaminating the natural agroecosystems with an advantage of being innocuous to human health. The growth of nanotechnology has offered rapid development of bio and nanosensors for the detection of several composites which range from several metal ions, proteins, pesticides, to the detection of complete microorganisms. Therefore, the present review focuses on different bio and nanosensors employed for monitoring agricultural ecosystems and also trying to highlight the factor affecting their implementation from proof-of-concept to the commercialization stage.

Abstract Due to the global rise of the human population, one of the top-most challenges for poor and developing nations is to use the food produces safely and sustainably. In this regard, the storage of surplus food (and derived products) without loss of freshness, nutrient stability, shelf life, and their parallel efficient utilization will surely boost the food production sector. One of the best technologies that have emerged within the last twenty years with applications in the packaging of food and industrial materials is the use of green mode-based synthesized nanoparticles (NPs). These NPs are stable, advantageous as well as eco-friendly. Over the several years, numerous publications have confirmed that these NPs exert antibacterial, antioxidant, and antifungal activity against a plethora of pathogens. The storage in metal-based NPs (M-NPs) does not hamper the food properties and packaging efficiency. Additionally, these M-NPs help in the improvement of properties including freshness indicators, mechanical properties, antibacterial and water vapor permeability during food packaging. As a result, the nano-technological application facilitates a simple, alternate, interactive as well as reliable technology. It even provides positive feedback to food industries and packaging markets. Taken together, the current review paper is an attempt to highlight the M-NPs for prominent applications of antimicrobial properties, nanosensors, and food packaging of food items. Additionally, some comparative reports associated with M-NPs mechanism of action, risks, toxicity, and overall future perspectives have also been made.

Abstract Background Biogenic fabrication of nanoparticles from naturally occurring biomaterials involves plants, herbs, bacteria and fungi using water as neutral solvent, while chemical synthesis involves hazardous chemicals and leaves unwanted byproduct which unnecessarily pollute the environment. In order to prevent atmospheric pollution a safe, clean and green strategy for the synthesis of cupric oxide nanoparticles from aqueous leaf extract of Diospyros montana has been employed. D. montana of Ebenaceae family is a poisonous tropical plant which grows wild in Asia. Its extract is commonly known as fish poison. The rate of formation of NPs from plant extract is thought to be facile and rapid relative to those formed by fungi and bacteria, but it depends on the concentration of reducing chemicals available in the extract. We report, in this communication, a benign method of biogenic synthesis of cupric oxide nanoparticles (CuO-NPs) from leaf extract of D. montana and their characterization by UV–visible, FTIR, SEM, TEM, DLS, SAED and EDX analyses. Their antimicrobial activity against seven Gram-positive and four Gram-negative bacteria has been screened. Photocatalytic degradation of methylene blue by ascorbic acid as reducing agent and cupric oxide nanoparticles as catalyst has been done under sunlight. Results Cupric oxide nanoparticles of varying size starting from 5.9 to 21.8 nm have been fabricated from aqueous leaf extract of D. montana at room temperature. The pure extract absorbs at 273 nm while CuO-NPs exhibit a broad peak at 320 nm. FTIR spectrum of the leaf extract shows the presence of a double quinonoid molecule. There are three types of CuO-NPs with different hydrodynamic radii. Their average hydrodynamic radii fall between 495 ± 346 nm. SEM and TEM images show spherical shaped CuO-NPs of different size. SAED suggests crystalline nature of CuO-NPs. They are highly polydispersed in solution. EDX analysis reveals the presence of Ca, C, O, Na and Si besides copper. Oxygen content is over 50% by mass. Reduction of methylene blue dye (MB) by ascorbic acid as reducing agent, in presence of CuO-NPs as catalyst, has been achieved in 90 s at room temperature while their reduction by ascorbic acid alone takes more than 10 min. Antibacterial activity of CuO-NPs against seven Gram-positive (Staphylococcus aureus, Streptococcus mutans, Streptococcus pyogenes, Streptococcus viridans, Staphylococcus epidermidis, Corynebacterium xerosis and Bacillus cereus) and four Gram-negative bacterial strains (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Proteus vulgaris) has been investigated. The results indicated that NPs are highly effective against growth inhibition of Gram-positive bacteria than Gram-negative bacteria. Copper oxide nanoparticles are even more toxic than the standard antibiotic, norfloxacin. Conclusion In this project cupric oxide NPs of 5.9–21.8 nm have been fabricated from aqueous leaf extract of D. montana. It is most inexpensive and easy process to fabricate NPs from plant material because no toxic chemicals are used. Since CuO-NPs are toxic to several Gram-positive and Gram-negative bacterial strains, attempt may be made to use them as antibacterial agent to protect food, vegetable and crops. Also, the reduction of methylene blue dye by ascorbic acid as reducing agent in presence of CuO NPs as catalyst has been done very efficiently at a rapid rate which prompts us to use them as catalyst in the reduction of dyes, other toxic materials and industrial effluents. Further investigation of other beneficial properties of CuO-NPs can also be explored.

Fruits and vegetables are an important part of a healthy diet. In this regard, Carica papaya (papaya) is one of them, a native to Mexico and northern South America, now naturalized in many parts of the world including tropical and subtropical regions. The papaya fruit pulp is rich in minerals and many vitamins, while seed contains glucosinolates, tocopherols, carotenoids, and benzyl isothiocyanate. Papaya is known for numerous activities such as antioxidant, antibacterial, anticancer activity, anti-fertility agent, anti-inflammatory, antiulcer, antidiabetic, hepatoprotective, and many more due to the presence of phenolics, flavonoids, and alkaloids as the key phytochemicals. Many commercial products obtained from different plant parts are available in the market and are being utilized for various purposes. More specifically, papaya fruit is used to produce a large number of processed foods such as jam, jelly, pickle, candied fruit, puree, concentrate, and canned slices/chunks. Fruit peels find its application in cosmetics, in wastewater treatment, as animal feed, and as a binder in ceramics. Papaya leaf, bark, root, and seeds have also shown the insecticidal and repellent activities. More interestingly, in the recent past, papaya and different parts are used for nanoparticle synthesis which has shown numerous applications. This review mainly focuses on the various phytochemicals present in different parts of plant C. papaya, their pharmacological activities, and several other applications. For writing this review paper, a literature survey was carried out via classic books of medicinal and fruit plants. Online scientific databases, for instance, PubMed, Scopus, Sci Finder, Science Direct, the Web of Science, Wiley Online, Google Scholar, ResearchGate, and other search engines were explored up to October 2020 to detect valid reports, studies, and investigations. All literature on the proposed topics were analyzed and summarized in this review paper.

Dodonaea (family Sapindaceae) - a genus of flowering plant (above 70 species recorded) and used for various activities. Dodonaea viscosa, D. angustifolia, D. spatulate, D. polyandra and D. ceratocarpa are well-known species of this genus. In spite of the possible health support, different plant species from this genus are not extensively noticed in the modern medicine system. Dodonaea genus has been traditionally used in the treatment of scurvy, inflammation, kidney pain, sore throat, intestinal parasite, herpes, wounds burn, rheumatism, cough, backache, toothache, skin burn, skin infection, tumor and wound healing. Plant leaves, stem and fruits are occasionally used in the formulation of traditional medicine. In terms of phytoconstituents, flavonoids, flavones and their derivatives, terpenoids and saponins are major isolated compounds. They have shown antimicrobial, antioxidant, anti-inflammatory, antidiabetic, hepatoprotective and anti-plasmodial activities. Plants of Dodonaea genus show insecticide, weedicide, pesticide activity and exhibit allelopathic effect. Further, some isolated bacteria from roots of D. viscosa have been used in other plants as a plant growth-promoting rhizobacteria. Additionally, leaf extract has also been used in nanoparticle synthesis. These particles have shown a significant antioxidant activity; and antibacterial activity towards both gram positive and gram negative bacteria. Overall, this review paper aims to describe the different aspects of Dodonaea genus such as botanical description, ethnomedicinal uses, phytochemistry, pharmacological and agricultural applications of Dodonaea genus. Besides, some other miscellaneous studies and applications have been also reviewed.

Abstract Since green mode of nanoparticles (NPs) synthesis is simple, advantageous and environment friendly relative to chemical and physical procedures, various plant species have been used to fabricate copper and copper oxide nanoparticles (Cu/CuO-NPs) owing to the presence of phytochemicals which often act as capping as well as stabilizing agent. These Cu/CuO-NPs are highly stable and used in the degradation of organic dyes like methylene blue and reduction of organic compounds such as phenols. They are also used as antibacterial, antioxidant and antifungal agent due to their cytotoxicity. They are also examined for agricultural crops growth and productivity. Cu-NPs increased the root and shoot growth of mung bean. In wheat plants, these particles reduced shoot growth; and enhanced the grain yield and stress tolerance through starch degradation. Similarly, CuO-NPs treated seedlings have shown reduced chlorophyll, carotenoid and sugar content, whereas proline and anthocyanins were increased in Brassica rapa seedlings. Overall, this review presents the recent understanding of plant-mediated Cu and CuO-NPs fabrication and their application in biomedicine, environmental remediation and agricultural practices. A comparison of the traditional/conventional method of fabrication of NPs with those of green protocols has also been made. Some misconception of copper chemistry has also been critically discussed in terms of oxidation and reduction reactions.

Abstract Jasmonates (JAs) are universally known lipid-derived phytohormones which regulate overall plant growth under both abiotic and biotic stresses. They are helpful in developing root and reproductive system in plants. Also, JA signaling triggers gene expression. They coordinate with other plant hormones under changing environmental conditions. JAs alone or sometimes in combination with other plant hormones ameliorate stress conditions. They also participate in upregulation of antioxidant metabolism, osmolyte synthesis, and metabolite accumulation. Pretreatment and/or exogenous application of JA exhibited multi-stress resilience under changing environment as well as other biotic stress conditions. The present review focuses on our current understanding of how plants respond to JAs’ application under extremely low or high temperature, highly alkaline condition, or even when attacked by herbivorous insects/animals. As a consequence of injury, the plant produces defense molecules to protect itself from damage. Their major role and mechanism of action under heavy metal/metalloid-induced toxicity have also been discussed.

The combination of green-nanotechnology and biology may contribute to anticancer therapy. In this regard, using gold nanoparticles (GNPs) as therapeutic molecules can be a promising strategy. Herein, we proposed a novel biocompatible nanogold constructed by simply microwave-heating (MWI) Au3+ ions and kenaf seed (KS) extract within a minute. The phytoconstituents of KS extract have been utilized for safe synthesis of gold nanoparticles (KS@GNPs). The biogenic KS@GNPs were characterized by UV-vis Spectra, TEM, HR-TEM, XRD, FTIR, DLS, EDX, and SEAD techniques. The legitimacy and toxicity concern of KS@GNPs were tested against RAW 264.7 and NIH3T3 cell lines. The anticancer efficacy was verified using LN-229 cells. The pathways of KS@GNPs synthesis were optimized by varying the KS concentration (λmax 528 nm), gold salt amount (λmax 524 nm), and MWI times (λmax 522 nm). TEM displayed spherical shape and narrow size distribution (5–19.5 nm) of KS@GNPs, whereas DLS recorded Z-average size of 121.7 d·nm with a zeta potential of −33.7 mV. XRD and SAED ring patterns confirmed the high crystallinity and crystalline face centered cubic structure of gold. FTIR explored OH functional group involved in Au3+ ions reduction followed by GNPs stabilization. KS@GNPs exposure to RAW 264.7 and NIH3T3 cell lines did not induce toxicity while dose-dependent overt cell toxicity and reduced cell viability (26.6%) was observed in LN-229 cells. Moreover, the IC50 (18.79 µg/mL) treatment to cancer cell triggered cellular damages, excessive ROS generation, and apoptosis. Overall, this research exploits a sustainable method of KS@GNPs synthesis and their anticancer therapy.

Abstract Background Biogenic fabrication of silver nanoparticles from naturally occurring biomaterials provides an alternative, eco-friendly and cost-effective means of obtaining nanoparticles. It is a favourite pursuit of all scientists and has gained popularity because it prevents the environment from pollution. Our main objective to take up this project is to fabricate silver nanoparticles from lichen, Usnea longissima and explore their properties. In the present study, we report a benign method of biosynthesis of silver nanoparticles from aqueous-ethanolic extract of Usnea longissima and their characterization by ultraviolet–visible (UV-vis), Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) analyses. Silver nanoparticles thus obtained were tested for antimicrobial activity against gram positive bacteria and gram negative bacteria. Results Formation of silver nanoparticles was confirmed by the appearance of an absorption band at 400 nm in the UV-vis spectrum of the colloidal solution containing both the nanoparticles and U. longissima extract. Poly(ethylene glycol) coated silver nanoparticles showed additional absorption peaks at 424 and 450 nm. FTIR spectrum showed the involvement of amines, usnic acids, phenols, aldehydes and ketones in the reduction of silver ions to silver nanoparticles. Morphological studies showed three types of nanoparticles with an abundance of spherical shaped silver nanoparticles of 9.40–11.23 nm. Their average hydrodynamic diameter is 437.1 nm. Results of in vitro antibacterial activity of silver nanoparticles against Staphylococcus aureus, Streptococcus mutans, Streptococcus pyrogenes, Streptococcus viridans, Corynebacterium xerosis, Corynebacterium diphtheriae (gram positive bacteria) and Escherichia coli, Klebsiella pneuomoniae and Pseudomonas aeruginosa (gram negative bacteria) showed that it was effective against tested bacterial strains. However, S. mutans, C. diphtheriae and P. aeruginosa were resistant to silver nanoparticles. Conclusion Lichens are rarely exploited for the fabrication of silver nanoparticles. In the present work the lichen acts as reducing as well as capping agent. They can therefore, be used to synthesize metal nanoparticles and their size may be controlled by monitoring the concentration of extract and metal ions. Since they are antibacterial they may be used for the treatment of bacterial infections in man and animal. They can also be used in purification of water, in soaps and medicine. Their sustained release may be achieved by coating them with a suitable polymer. Silver nanoparticles fabricated from edible U. longissima are free from toxic chemicals and therefore they can be safely used in medicine and medical devices. These silver nanoparticles were stable for weeks therefore they can be stored for longer duration of time without decomposition.

Abstract Nanomaterials (NMs) are receiving remarkable attention due to their unique properties and structure. They vary from atoms and molecules along with those of bulk materials. They can be engineered to act as drug delivery vehicles to cross blood-brain barriers (BBBs) and utilized with better efficacy and safety to deliver specific molecules into targeted cells as compared to conventional system for neurological disorders. Depending on their properties, various metal chelators, gold nanoparticles (NPs), micelles, quantum dots, polymeric NPs, liposomes, solid lipid NPs, microparticles, carbon nanotubes, and fullerenes have been utilized for various purposes including the improvement of drug delivery system, treatment response assessment, diagnosis at early stage, and management of neurological disorder by using neuro-engineering. BBB regulates micro- and macromolecule penetration/movement, thus protecting it from many kinds of illness. This phenomenon also prevents drug delivery for the neurological disorders such as Alzheimer’s disease (AD), Parkinson’s disease (PD), multiple sclerosis, amyotrophic lateral sclerosis, and primary brain tumors. For some neurological disorders (AD and PD), the environmental pollution was considered as a major cause, as observed that metal and/or metal oxide from different sources are inhaled and get deposited in the lungs/brain. Old age, obesity, diabetes, and cardiovascular disease are other factors for rapid deterioration of human health and onset of AD. In addition, gene mutations have also been examined to cause the early onset familial forms of AD. AD leads to cognitive impairment and plaque deposits in the brain leading to neuronal cell death. Based on these facts and considerations, this review elucidates the importance of frequently used metal chelators, NMs and/or NPs. The present review also discusses the current status and future challenges in terms of their application in drug delivery for neurological disease management.

Abstract Background Soil salinity is considered as one of the major environmental factors that has reduced plant productivity worldwide. This study investigates the impact of salinity on plant growth attributes, biochemical and physiological leaf characteristics in two cultivars (Adet and Merawi) of Brassica carinata and also explores the role of salicylic acid (SA) in mitigating the effect of salt stress. Methods Four-week-old cultivars were treated with NaCl (50, 100 and 150 mM) and SA (0.5 mM) and watered regularly with 100% field capacity. Thus, they were grown under eight different treatments (T1 = no NaCl, no SA; T2 = 0 mM NaCl with 0.5 mM SA; T3 = 50 mM NaCl without SA; T4 = 50 mM NaCl with 0.5 mM SA; T5 = 100 mM NaCl without SA; T6 = 100 mM NaCl with 0.5 mM SA; T7 = 150 mM NaCl without SA; and T8 = 150 mM NaCl with 0.5 mM SA). Nine-week-old cultivars were sampled for analyzing the growth attributes, plant water status, nitrate reductase activity, proline accumulation, photosynthetic traits, lipid peroxidation level and activity of antioxidant enzymes. Results Salinity treatments hampered the overall plant growth performance in a dose-dependent manner. Salinity also reduced photosynthetic efficiency by inhibiting chlorophyll synthesis, nitrate reductase activity, chlorophyll fluorescence, stomatal conductance, net photosynthetic and transpiration rates and plant water status. On the other hand, SA application alleviated the adverse effects of salinity and improved the performance of the studied parameters in both the cultivars. Higher dose of salinity increased proline production, but SA application mitigates this impact in both the cultivars studied. The activity of antioxidant enzymes increased under salt stress in a dose-dependent manner. SA treatment to normal or salinity-stressed plants increased the enzymes activity, showing that SA has a crucial role in modulating the cell redox balance and protecting the plants from oxidative damage. SA significantly reduced the salinity-caused effects on the overall performance of plants and their antioxidant systems in both the cultivars. Of the two cultivars, Adet was more tolerant to salinity than Merawi. Conclusions Foliar application of SA improved the performance of Ethiopian mustard cultivars and mitigated the damage caused by salt stress.

Abstract Zinc oxide is an essential ingredient of many enzymes, sun screens, and ointments for pain and itch relief. Its microcrystals are very efficient light absorbers in the UVA and UVB region of spectra due to wide bandgap. Impact of zinc oxide on biological functions depends on its morphology, particle size, exposure time, concentration, pH, and biocompatibility. They are more effective against microorganisms such as Bacillus subtilis, Bacillus megaterium, Staphylococcus aureus, Sarcina lutea, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia, Pseudomonas vulgaris, Candida albicans, and Aspergillus niger. Mechanism of action has been ascribed to the activation of zinc oxide nanoparticles by light, which penetrate the bacterial cell wall via diffusion. It has been confirmed from SEM and TEM images of the bacterial cells that zinc oxide nanoparticles disintegrate the cell membrane and accumulate in the cytoplasm where they interact with biomolecules causing cell apoptosis leading to cell death.

Abstract Background Plants are rich in secondary metabolites and are being used for the treatment of various ailments in the indigenous system of medicine. Many developing countries are facing illnesses, and deaths among children are caused by germs, which get into the mouth via water and food. In addition, it has been estimated that up to 80% of all disease and sickness in the world is caused by inadequate sanitation, polluted water or unavailability of water. Thus, this study investigates the water purifying property of Moringa oleifera seed powder and determines the role of seed extracts against a few bacterial growths. Methods Water samples were obtained randomly during January and February, 2015, from the Angereb and Shinta rivers, Gondar, Ethiopia. Both sites of water samples were subjected for purification studies and treated with dried seed powder. Treated water samples were subjected to bacteriological analysis using most probable number technique. Results Addition of aluminum sulfate as a coagulant lowered the water pH from 7.2 to 3.66, while the seed extract water pH remained the same. Treatment of 0.016 g/L of M. oleifera decreased water turbidity from 208.3 nephelometric turbidity units (NTU) to 33.66 NTU (83.84%) and from 129 NTU to 16.8 NTU (86.98%) for the Shinta and Angereb river water samples, respectively. The highest microbial load reduction was found with the Angereb (97.17%) and Shinta (97.50%) rivers. The acetone extracts showed maximum antibacterial activity with 19.00 mm against Salmonella typhii (clinical isolate), while Shigella dysenteriae (clinical isolate) was the least sensitive with 7.66 mm on the aqueous extract. The most frequent MIC value was 6.25 mg/mL followed by 12.5 mg/mL. The acetone extract is the most potent in inhibiting and killing the test organisms at a very low concentration for Shigella typhii. Conclusion Taken together, the seed powder exhibits a remarkable reduction in turbidity and coliform count which makes the seed powder a good source for water purification. The acetone extract of seed had a strong antibacterial activity. It reveals that the seed powder and its extract can control and reduce waterborne bacterial diseases. This investigation facilitates benefits to those who cannot afford and or have access to clean drinking water in Ethiopia and elsewhere.

Abstract Use of silver and silver salts is as old as human civilization but the fabrication of silver nanoparticles (Ag NPs) has only recently been recognized. They have been specifically used in agriculture and medicine as antibacterial, antifungal and antioxidants. It has been demonstrated that Ag NPs arrest the growth and multiplication of many bacteria such as Bacillus cereus, Staphylococcus aureus, Citrobacter koseri, Salmonella typhii, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumonia, Vibrio parahaemolyticus and fungus Candida albicans by binding Ag/Ag+ with the biomolecules present in the microbial cells. It has been suggested that Ag NPs produce reactive oxygen species and free radicals which cause apoptosis leading to cell death preventing their replication. Since Ag NPs are smaller than the microorganisms, they diffuse into cell and rupture the cell wall which has been shown from SEM and TEM images of the suspension containing nanoparticles and pathogens. It has also been shown that smaller nanoparticles are more toxic than the bigger ones. Ag NPs are also used in packaging to prevent damage of food products by pathogens. The toxicity of Ag NPs is dependent on the size, concentration, pH of the medium and exposure time to pathogens.