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Application of Nanobiofertilization for Bioremediation and Ecorestoration of Polluted Soil/Farmland

Oluwafemi Adebayo Oyewole1, Konjerimam Ishaku Chimbekujwo2*, Margaret Oniha3, Isibor Patrick Omoregie3, Opeyemi Isaac Ayanda3, Charles Oluwaseun Adetunji4 and John Tsado Mathew5

1Department of Microbiology, Federal University of Technology, Minna, Nigeria

2Department of Microbiology, Modibbo Adama University, Yola, Nigeria

3Department of Biological Sciences, Covenant University, Ota, Nigeria

4Department of Microbiology, Edo State University, Uzairue, Nigeria

5Department of Chemistry, Ibrahim Badamasi Babangida University, Lapai, Niger State, Nigeria

Abstract

Nanotechnology is a novel field of research that solves issues in relation to environmental contamination. It opens doors for an environmentally friendly substitutes without altering the ecosystem. The combination of the two methods, nanobiofertilization and bioremediation is a recently developed approach which gives hope for decontamination of the environment and restoring a livable future. It has proven to effectively absorb contaminates in a short period of time and in a friendlier manner. Microorganisms in nanobioremediation play an important role in the removal, detoxifying, degrading, and immobilization of pollutant into less toxic form. Bio- and phytoremediations are exclusively preferred approaches because of the edge it has over numerous methods like high waste cleaning abilities, its cheap, ecofriendly, and generally acceptable. This approach has exceptionally added to the tolerability and ecorestoration of the environment based on the upper hand it has over other innovations. More so, its efficacy signifies high level of pollutant removal and has lay out new prospect to tackle problem within the environment.

Keywords: Nanobiofertilization, bioremediation, ecorestoration, pollution, nanobioremediation, nanoparticle

1.1 Introduction

Soil pollution poses a danger to livelihoods, quality of life, and sustainable development [1]. Therefore, safeguarding soil is imperative in the present time due to the pressures of a growing population and the reduction of cultivable land caused by human activities. Nanotechnological methods are emerging as one of the most modern approaches to restoring the environment, which can be utilized to eliminate various pollutants. The integration of nanoparticles with microorganisms enhances degradation of harmful contaminants in the environment [2].

Soil restoration is one primary field where nanotechnological approaches have been extensively utilized. Recently, nanobioremediation (NBR) has been used in addressing soil pollution via biodegradation using nanoparticles. Nanobioremediation is concerned with the integration of plants or microorganism with nanoparticles to eliminate pollutants in the environment [3] through various mechanisms, basically precipitation, adsorption, co-precipitation, and redox reactions [4]. This mechanism is facilitated as a result of their exceptionally large surface area of the particle [5]. By utilizing nanoparticles (NPs), hyperaccumulators and native soil microorganisms can enhance biodegradation processes, thus expanding the potential scope of restoration. This approach can be referred to as nanophytoremediation and microbe-mediated nanorestoration [6]. Given the rising costs of chemical and physical techniques, phytoremediation and bioremediation have gained ground. The reason nanoparticles is combined with bioremediation is because of their surface area being able to interact with the surroundings, enhancing the remediation process. Therefore, nanobioremediation aims to reduce the concentration of pollutants to an extent that is deemed safe, while also minimizing secondary environmental effects. Additionally, this reclamation approach is very effective, quicker, and eco-friendly compared to bioremediation methods [7]. Nanobioremediation (NBR) uses a technique that require the application of nanocatalyst to breakdown pollutants by enabling them to penetrate down into pollutants, thus carrying out the entire process safely without altering the environment [3]. The establishment of the connection between microorganisms and nanoparticles is crucial to effectively utilized the technique [8]. The surface covering, size, nature, and chemical makeup of nanoparticles influences the kind of interactions the exist between NPs, organisms, and pollutants. Additionally, the type of pollutants organism used and environmental factors are known to significantly affect the process [9]. Pollutants are usually dissolved, assimilated, and transformed as a result of the interactions between microorganism and nanoparticles [10]. However, interactions between NPs and biota may be harmful or stimulated, leading to either a positive or negative impact on the microbial performance in the NBR process [11].

1.2 Nanoparticles

Nanoparticles (NPs) are molecular aggregates with smaller sizes ranging from 1-100 nm, this alters their physico-chemical characteristics in comparison to the bulk materials [12]. Nanoparticle sizes define their characteristics [12]. Nanoparticles' small size and large surface area has aided its stability, surface modification, and biocompatibility [13]. Nanoparticles could either be in the form of rods, round, box, or triangular shapes [14]. Nanomaterials are essentially divided into three sorts primarily based on their materials [15] such as the inorganic (metallic, metallic oxide), carbon (nanotubes), and polymer. Polymer is most preferred because of their capacity to the identify and remove heavy metals [16]. Sensors are produced as a result of small size, which are used in controlled locations. Nanoparticles have gained more ground because of their efficacy, low cost, and are ecofriendly substitutes to perfectly eliminated toxic chemical substances, poisonous end product, and environmental clean-up [2]. Microorganisms have reportedly been used to manufacture different nanoparticle including gold, zinc, silver, copper, and iron [17]. Biosynthesis of nanoparticles is growing rapidly within nanotechnology because it employs numerous biological entities within the process [18]. Nanomaterials additionally can be engineered to broaden quite miniature, correct, and sensitive pollutants-tracking gadgets. Nanoparticles as sensor not only tract pollutants but also break them down to a less poisonous form [19]. The use of nanoparticles in site remediation has presented a great opportunity for the cleanup of the environment [20]. The involvement of nanoparticles in the breakdown and chemical reduction has created an avenue to control pollution. This particle is applicable in vast areas of bioremediation like in wastewater and hydrocarbon remediation [21].

1.2.1 Nanoparticles as Nano-Adsorbents

The nanomaterials work with greater achievements when taken up both inorganic and natural waste from water [22]. Nano-absorbents have been applied in many fields of life due to their unique chemical and physical properties [23]. Particles are able to stick to surfaces due to the property of adsorption. Physical adsorption is triggered by means of an interplay caused by Vander Waals force involving sharing of electron while in the chemical perspective, it takes place via a bond existing between the adsorbent and adsorbate and the fabric, the chemical adsorbed is hard to be removed. The process is irreversible while the physical is reversible [24]. In wastewater remedy, nanomaterial as an absorbent is environmentally friendly based on its pore and surface sizes, site of absorption, moderate temperature, and surface interaction properties. The capacity of the nanomaterial is based on its physical characteristics and shape [24]. There are four exclusive kinds of nano-absorbent which are: polymeric, carbon nanotube, zeolites, and metals [24]. Table 1.1 shows the list of nanomaterials, adsorbate and their adsorption capacity.

1. Carbon nanotube is circular, having excessive sorption and surface sites with one or more nanotube wall [25]. The water-resistant form of nanomaterials stops the reduction of its activity on the surface. The interplay between nanotube and metallic positive charge is a result of the electrostatic desirability and chemical bond [26], and this aids in waste removal from sewage [27]. Desalination by means of adsorption strategies nevertheless constrained due to excessive energy consumption and technical problems; however, the usage of long plasma altered carbon tubes remove pollutant and salts effectively in contrast to the ordinary absorbent when purifying wastewater [28]. The fundamental hinderance for its industrial scale utility is its manufacturing price.
2. Nano polymeric adsorbent is the most enhanced approach than the traditional approach and has greater relevance in some situations [29] due to some interesting properties like pores arrangement, rigidity, surface attraction adaptability, and large surface area [30]. Carbon polymer, metal and metal oxide, graphene, and dendrimer are categorically formed based on the polymeric composition of the nanomaterial [31]. The makeup of dendrimer nanopolymer has an internal water-resistant portion which removes both inorganic and natural pollutant and a surface area that also removes heavy metals. Based on its molecule branched repeat structure, it is said to be the ideal...