Phytosynthesis of nanoparticles: concept, controversy and application

Nanotechnology is an exciting and powerful discipline of science; the altered properties of which have offered many new and profitable products and applications. Agriculture, food and medicine sector industries have been investing more in nanotechnology research. Plants or their extracts provide a biological synthesis route of several metallic nanoparticles which is more eco-friendly and allows a controlled synthesis with well-defined size and shape. The rapid drug delivery in the presence of a carrier is a recent development to treat patients with nanoparticles of certain metals. The engineered nanoparticles are more useful in increasing the crop production, although this issue is still in infancy. This is simply due to the unprecedented and unforeseen health hazard and environmental concern. The well-known metal ions such as zinc, iron and copper are essential constituents of several enzymes found in the human system even though the indiscriminate use of similar other metal nanoparticle in food and medicine without clinical trial is not advisable. This review is intended to describe the novel phytosynthesis of metal and metal oxide nanoparticles with regard to their shape, size, structure and diverse application in almost all fields of medicine, agriculture and technology. We have also emphasized the concept and controversial mechanism of green synthesis of nanoparticles

Current status of plant metabolite-based fabrication of copper/copper oxide nanoparticles and their applications: a review

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

Water purification and antibacterial efficacy of Moringa oleifera Lam

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

Light emitting diode (LED) lights for the improvement of plant performance and production: A comprehensive review

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