Chapter 14 - Nanotechnological applications in agro-waste management with special reference to Indian agricultural sector

Agricultural wastes are considered residues resulted from the agricultural production and after harvesting fruit and vegetable and their processing, agro-industrial by/co-products from the grapes, banana, olives and milk processing. These wastes may represent a treasure when they are turning into valuable applications (i.e., composting, biochar, removing pollutants from the environment and organic fertilizers) or they may burn in open fields causing some environmental problems such as soil degradation and air pollution. The landfill disposal and open dumping of agro-wastes is a common practice in the developing countries generating huge amounts of ash, which may create serious health and environmental problems, primarily due to pollution of groundwater. Under the umbrella of the bioeconomy and based on industrial innovation and high technology, new and better approaches for the recovery of agricultural wastes have been developed. This has contributed to guaranteeing sustainable production and its consumption, resource efficiency, the conversation of these wastes into valuable products and the reduction of negative environmental impacts. The common management of Agro-wastes may include a lot of suggested uses such as production of biosynthesis of nanoparticles, biotechnological products, composting and biofuel production. A lot of bioactive compounds could be produced from the agro-wastes, which have many application possibilities such as functional food, pharmaceutical and cosmetic approaches. The nano-management of agro-wastes may include using of nanotechnology to convert the agro-wastes into a valuable product. This topic still has several open questions particularly under the sustainable and bioeconomy.

The rapid depletion of fossil fuel has pushed mankind to think about alternative fuel sources for a smart future. In this direction, biofuel is the most promising source of sustainable energy because of its environment-friendly and green nature. The production of biofuels is boosted by the application of nanoscience and nanotechnology. Nanomaterials show a better performance in the processing and production of biofuel due to the high surface-to-volume ratio and related high reactivity of these materials. Nanotechnology helps in enzyme immobilization and reduces production costs by recovering and reusing the catalysts. In this chapter, the use of various nanocatalysts and nanomaterials to improve the processing and production of biofuels are discussed in detail. The current status of biofuels for controlling the energy crisis and applications of nanotechnology in the production of various types of biofuel has been put forth. Further, issues and prospects regarding the nanotechnological and economic feasibility of the biofuel production process are also discussed in this chapter.KeywordsNanotechnologyBiofuelImmobilizationNanocatalystNanomaterialRenewable energy

Biofuels have received increasing attention as an alternate fuel to replace fossil fuels. Fossil fuels are nonrenewable and produce greenhouse gases, which cause global warming and climatic changes. The rate at which fossil fuels are used greatly exceeds their replenishment and hence there is a need for alternative fuels such as bioethanol, biodiesel, biogasoline, and biogas. Biofuels, being environmental friendly and renewable fuel resources, have attracted extensive attention as the best alternative energy source. Nanotechnology finds its potential application in biofuel production for developing efficient catalysts. Enzymes have a significant role in the biomass conversion processes. Enzymes are used for the hydrolysis of complex sugars in agricultural wastes and vegetable wastes to simple fermentable sugar. Enzymes can also catalyze the transesterification of lipids for biodiesel. The activity of these enzymes, their half-life, and recovery of enzymes can be greatly increased using nanotechnology. Carbon metallic/nonmetallic nanoparticles provide a larger surface area for immobilization of enzymes. One of the advantages of using zinc/nickel/iron nanoparticles is that they can serve as cofactors for enzyme catalysis and biofuel production. Nanotechnology improves the process of production, yielding higher amounts of biofuels. Enzymes involved in biofuel production are immobilized on nanoparticles, nanofibers, and nanotubes. Magnetic nanoparticles are widely used in biogas production which is an anaerobic process facilitated by microbiota and the presence of these metal ions increases the activity of methanogenic bacteria for a higher yield with good substrate conversion efficiency. Nanotechnology is a successful tool for sustainable production of bioenergy. This chapter gives a detailed overview on various aspects such as the recent global scenario of biofuel and bioenergy, emphasizing the significant application of nanotechnology in providing solutions for bioenergy and biofuel production. Also, the chapter highlights the various enzymes involved in biofuel and bioenergy production, and their association with nanotechnology and safety issues.

Nanomaterials have the potential to revolutionize the microalgae industry by addressing challenges faced by microalgae biorefinery and enabling sustainable production of biomass, biofuels, and high-value compounds. There is a growing emphasis on harnessing nanotechnology to accelerate the progress and development of microalgae biomass as a viable and eco-friendly feedstock for producing biofuels and other valuable products. This study presents a comprehensive bibliometric analysis of global research trends on microalgae – nanoparticle studies from 2010 to 30th October 2025. Data were retrieved from the Web of Science (WoS). A total of 2,330 relevant documents were identified and analyzed using the WoS, VOSviewer and Microsoft Excel. Results revealed that research articles were the most dominant publication type (83.4%), followed by review papers (10.8%). Publication output increased steadily over the years, reflecting rising scientific interest in nanotechnology-enhanced microalgae research. The global distribution of publications revealed Asia as the leading contributor, with China (498) and India (476) ranking highest, followed by the USA (314). In Africa, Egypt (128) contributes the most, followed by South Africa (24), Nigeria (15), and Ethiopia (14). The keyword co-occurrence analysis revealed four major thematic research clusters: nanoparticle toxicity and environmental impacts, nanoparticle-enhanced microalgae biorefinery for biofuel production, green synthesis of nanoparticles using microalgae, and metal oxide nanoparticle interactions with freshwater microalgae. Overall, this bibliometric analysis highlights growing interdisciplinary focus and provides valuable insight for guiding future research directions in microalgae – nanotechnology applications.

Recent development of nanobiomaterials in sustainable agriculture and agrowaste management

The applications and benefits of nanotechnology in the agricultural sector have attracted considerable attention, particularly in the invention of unique nanopesticides and nanofertilisers. The contemporary developments in nanotechnology are acknowledged and the most significant opportunities awaiting the agriculture sector from the recent scientific and technical literature are addressed. This review discusses the significance of recent trends in nanomaterial-based sensors available for the sustainable management of agricultural soil, as well as the role of nanotechnology in detection and protection against plant pathogens, and for food quality and safety. Novel nanosensors have been reported for primary applications in improving crop practices, food quality, and packaging methods, thus will change the agricultural sector for potentially better and healthier food products. Nanotechnology is well-known to play a significant role in the effective management of phytopathogens, nutrient utilisation, controlled release of pesticides, and fertilisers. Research and scientific gaps to be overcome and fundamental questions have been addressed to fuel active development and application of nanotechnology. Together, nanoscience, nanoengineering, and nanotechnology offer a plethora of opportunities, proving a viable alternative in the agriculture and food processing sector, by providing a novel and advanced solutions. © 2017 Society of Chemical Industry.

Application of nanotechnology truly brought advancement on different fields, including electronics, energy, environment, health sectors, agriculture and allied fields. Breakthrough on the application of nanotechnology in agriculture has revolutionized the plant production, plant protection, processing, and packaging transportation of agricultural products. Today, nanotechnology is widely utilized in the field of fisheries, including fish nutrition, fish health and detection, and water management. It has showed significant effect in improving the specificity and sensitivity on detecting opportunistic pathogens that attacked aquaculture species; development of efficient and effective nanovaccines and supplements; enhance the quality, absorption properties, bioavailability, and blending properties of the feed which significantly affect the growth rate of aquaculture species; and also showed excellent result in the purification of water resources including the elimination of unwanted contaminants. In this regard, this review aims to explore the different research and current trends, including issues and concerns on the application of nanotechnology in aquaculture.

Recently, applications of nanotechnology are in the lime light in all the sectors including food and nutrition. Food nanotechnology is becoming new frontiers of this century. The applications of nanotechnology in food and agriculture sector are comparatively more recent than the nano-drugs and nanopharmaceuticals. Smart and efficient delivery of active food components, protein bioseparation, nanoencapsulation of nutraceuticals are few of the emerging topics in food and agriculture nanotechnology. Other advancement in food and agriculture biotechnology is the nano-films and their applications in packaging also the smart materials for sensing properties make it more fit to be used in food and agriculture sector. Industrialists, scientists and researchers are focusing to meet their need with the help of nanotechnology e.g. high nutrition level, efficient nutritional delivery, more shelf life, good mechanical properties as well as longer shelf life and durability of food-products. In this review, we have summarized the applications of nanotechnology in food and nutraceuticals and also have identified the outstanding challenges to be overcome which further indicates future of this food nanotechnology. Here in this review, we have described (i) the recently launched marketed nano-foods; (ii) major applications of nanotechnology in food and its allied sectors (iii) challenges and opportunities in nano-food processing.

Indian agricultural growth has reduced from about 3.6% in 1985–1995 to less than 2% in 1995–2005. This is far below than the targeted 4% annual growth in agricultural sector for 2020. The major concern is food grain production. Among the many scientific advancements, nanotechnology (NT) has been identified as a potential technology for reviving the agriculture and food industry and can improve livelihood of poor. Various sectors like health care, materials, textile, information and communication technology (ITC), and energy can get huge benefits from nanotechnology. In agricultural sector in particular, nanotechnology plays an important role in crop production, food processing and packaging, food security and water purification, environmental remediation, crop improvement, and plant protection. Agricultural productivity can be improved through nanomaterial-induced genetically improved animals and plants, site-specific drug and gene delivery of molecules at cellular/molecular levels in animals and plants, and nano-array-based genetic modification in animals and plants in stress conditions. Nanotechnology has the potential of precise delivery of agrochemicals for improving disease resistance, plant growth, and nutrient use. Nanoencapsulated products show the ability of more effective and site-specific use of pesticides, insecticides, and herbicides in an eco-friendly and greener way. It is successfully used in postharvest for maintaining freshness, quality, and shelf life of stored product and preventing disease occurrences in a fairly safer way. The use of nanomaterials is quite new in agriculture and it requires additional research. Social and ethical repercussions of nanotechnology uses in agriculture have to be considered. Before commercialization and field application, toxicity of nanomaterials has to be evaluated.

Chapter 9 - The role of nanoparticles in sustainable agriculture

Numerous applications of nanochemistry and nanotechnology in electronics, medicine, catalysis, and environmental protection have become popular scientific disciplines in the last decades. Besides the presence of nanomaterials in pharmaceutical products, textiles, food, and packaging, or its applications in the catalysis of traditional organic synthesis at high efficiency, the relationship between nanoscience and environmental protection stands out. This relationship has two aspects. One aspect shows numerous possibilities of nanomaterials applications in drinking water treatment, wastewater treatment, gas emissions, and acceleration of anaerobic digestion in biogas production processes from organic waste, together with others. Another aspect is the production of nanomaterials from waste and its contribution to the valorization and elimination of waste that can significantly contribute to the environment. This chapter will show the tendency of nanochemistry and nanotechnology applications in sensors, catalytic degradations of pollutants, adsorption and filtration, and production of nanomaterials from industrial waste and the potential risks of nanomaterials.

Few valorization pathways have been implemented as alternatives to reduce the orange peel waste (OPW) disposal in landfills. OPW can be a source of income or economic savings in juice production factories since this waste is a potential source of value-added products (e.g., bioactive compounds) and energy vectors (e.g., biogas). Valorization alternatives should be based on (i) orange peel chemical composition, (ii) market analysis, and (iii) availability. Nevertheless, few literature papers have highlighted the chemical composition change caused by the different juice production schemes as a potential opportunity to obtain different value-added products and biorefinery schemes. Thus, the aims of this review paper are related to (i) reviewing different orange fruit processing pathways, (ii) analyzing several OPW chemical compositions reported in the open literature, (iii) providing a summary of OPW extraction pathways for bioactive compounds production, and (iv) evaluating the effect of applying different extraction methods on bioactive compound extraction performance. This review includes a description of the OPW matrix, market insights, packaging, physicochemical characterization, processing technologies, and suggested biorefinery approaches. Finally, different extraction methods for obtaining bioactive compounds from OPW are compared. As a result, the supercritical fluid extraction process has the highest extraction performance and selectivity since this method extracted a high amount of hesperidin (8.18 g/kg OPW db.). In conclusion, OPW is a source of bioactive compounds and valuable products that can be introduced in juice-producing factories to increase product portfolio or economic savings by changing the energy matrix.

In an interesting recent article in this Journal1 Richard C. Porter presents a model "to show that, in agrarian (or predominantly agricultural) economies it may be impossible to counteract apparently temporary shifts in the price level by means of traditional monetary policy". In Section III, to which this comment relates, he assumes a two-sector model, with one sector (agriculture) producing the single commodity (foodstuffs) in the economy and the other sector living on lump-sum transfer payments from the agricultural sector and producing nothing. These lump-sum taxes are fixed and in money form; Porter in a footnote (p. 61) assumes (incorrectly, as is discussed below) that "none of the conclusions would be altered if the tax were fixed in real terms". Output is independent of economic considerations (determined by the "caprice of nature"). A fixed money supply is given, as is a desire to hold a certain real wealth balance relative to real income and consumption. Speculation on the basis of expectations of price changes is assumed away. The non-agricultural sector holds its real wealth only in the form of money, while the agricultural sector holds both money and hoards of foodgrains. While Porter grants that we know almost nothing about "what causes changes (and by how much) in the relative proportions of foodgrain stocks and money in rural wealth balances", his analysis rests entirely on presumed changes in this fraction. As he indicates, with an unchanging fiaction, monetary policy is successful in maintaining a certain price level.

Microalgae are a group of photosynthetic microorganisms that can utilize atmospheric CO 2 as a carbon source. They are regarded as promising green cell factories for the production of biofuels and highly valuable products. However, the production of biofuels and other valuable products is currently not economically viable in microalgae, due to the low yield. Therefore, rational metabolic engineering of microalgae to obtain robust microalgal strains is required, and a comprehensive understanding of lipid metabolism is also essential. Moreover, state-of-the-art molecular genetic tools including synthetic biological strategies will also facilitate potentiation of microalgae as cell factories for bioresource and bioenergy production. Thus, it seems timely to launch this Research Topic to collect recent achievements on metabolic or process engineering in microalgae that can enhance the production of biofuels and other valuable products. This Research Topic includes eight research articles/original reviews on microalgal biology and biotechnology. These studies include strategic transgene selection, enzyme engineering, proteomic analysis, cultivation mode comparation, and mathematical modeling of growth. In addition, one review discussed the synthetic biology perspective on bioengineering tools for microalgae. Fluorescent proteins (FP) are useful reporters to monitor gene expression and subcellular localization. Gutiérrez et al. Demonstrated that a broad set of optimized synthetic FP can be used as fusion partners to monitor transgene expression in the eukaryotic model microalga Chlamydomonas reinhardtii (Figure 1A ). This technical advance will facilitate high-throughput screening of algal transformants to identify high transgenes expression or trait stacking cells, since the target recombinant-FP fusion protein can be visualized in situ after electrophoresis. In the green microalga Haematococcus pluvialis, a novel bifunctional wax ester synthase (HpWS), involved in early triacylglycerol (TAG) accumulation under high light conditions (HL), was identified (Figure 1B ) by Ma et al. Heterologous expression of HpWS in TAG-deficient Saccharomyces cerevisiae can restore the capability of wax and TAG biosynthesis. In addition, the overexpression of HpWS in Chlamydomonas reinhardtii enhanced TAG production (Ma et al.) This study provides a new molecular target for genetic manipulation to increase TAG and wax accumulation in microalgae. Dan et al. reported that overexpression of GlgP (glycogen phosphorylase) promoted effective glycogen

In recent years, potential of nanotechnology in agriculture and food biotechnology has received attention of agriculture/plant biotechnologists. Although the application of nanotechnology in the field of chemistry and physics are well known and several products resulting through the use of nanotechnology are already in the market, the application of nanotechnology in agriculture and food sector is relatively new and therefore, not so widely known. United States Department of Agriculture (USDA) was perhaps the first in addressing this issue, when they prepared a roadmap (published in September 2003) for the application of nanotechnology in agriculture and food. The prediction was that nanotechnology would transform the entire agriculture and food industries, changing the way the crops are grown and the food is produced, processed, packaged, transported, and consumed. After this initial effort in 2003, significant progress in the application of nanotechnology in agriculture and food has been made both in the developed and developing countries of the world. A brief account of the methods used in the application of nanotechnology in the field of agriculture and food industry and the progress already made through these applications will be presented in this Review.