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Arsenic (As) contamination in paddy soils and its further translocation to the rice is a serious global issue. Arsenic loading to the rice depends on soil physico-chemical parameters and agronomic practices. To minimize this natural threat, as a natural substance, rice straw was used to produce rice biochar (RBC) and doped with iron oxide (IO) nanoparticles, another eco-friendly composite. In this study, RBC was used at three different concentrations- 0.5%, 1%, and 1.5% alone as well as conjugated with fixed 20 ppm IO nanoparticles. These treatments were compared with the control soil and control plants that had only As in the setup, without any amendments. The application of these treatments was efficient in reducing soil As bioavailability by 43.9%, 60.5%, and 57.3% respectively. Experimental data proved a significant percentage of As was adsorbed onto the RBC + IO conjugate. Further, the 1% RBC + IO conjugate was found to be the best treatment in terms of making soil macro-nutrients bioavailable. Rice seedlings grown under this treatment was more stress tolerant and produced less antioxidant enzymes and stress markers compared to the control plants grown under As-stress only. Rice plants from these different growth setups were observed for internal anatomical integrity and found that the RBC alone and RBC + IO conjugate, both improved the internal vascular structure compared to the control plants. To minimize soil As stress in crops, IO-doped RBC was proven to be the best sustainable amendment for improving soil-crop quality and achieving the proposed motto of Sustainable Development Goals by the United Nations.

Thiourea (TU) is a chemo-priming agent and non-physiological reactive oxygen species (ROS) scavenger whose application has been found to reduce As accumulation in rice grains along with improved growth and yield. The present field study explored TU-mediated mechanistic changes in silicon (Si) assimilation in root/shoot, biochemical and molecular mechanisms of arsenic (As) stress amelioration in rice cultivars. Gosai and Satabdi (IET-4786) rice cultivars were selected for field experiment at three different places; control field and two other As contaminated experimental fields (EF1 and EF2) in West Bengal, India. The average As reduction was observed to be 9.5% and 19.8% whereas the yield increment was 8.8% and 17.7% for gosai and satabdi, respectively among all the three experimental fields. The positive interrelation was also observed between improved internal ultrastructure anatomy and enhanced Si assimilation (36%-423%) upon TU application. The level of photosynthetic pigments was increased by 29.8%-99.2%. Further, activities of antioxidant enzymes were harmonically altered in TU supplemented plants. The expression of various As related transporter genes in flag leaf and developing grains (inflorescence) was changed in both the rice cultivars (gosai and satabdi). It was also presumably responsible for observed As reduction in grains. Thus, TU application was found to be an efficient and sustainable agronomic practice for amelioration of As toxicity in rice plants in As contaminated field conditions.

The study implements a periodical intermittent water cycle during rice cultivation providing insight potential in minimizing soil bio-available arsenic. Soil As concentrations were 34 ± 0.49 and 72.03 ± 0.54 mg kg-1 As respectively in two selected fields with rice cultivars gosai and satabdi, in comparison to 42.26 ± 0.37 and 83.69 ± 0.48 mg kg-1 in continuously flooded field soil, determined through ICP-MS. The study found higher translocation of silicon from soil to rice plant parts under intermittent irrigation having pH range of 7.6–9.4 and greater availability of soil organic content that in turn release more labile silicon from soil to aqueous phase for plant accumulation. This increased uptake of silicon strengthens rice shoots, nodes and leaf xylem-phloem integrity compared to conventional continuously flooded rice cultivation approach, suppressing the arsenic translocation, as observed under FE-SEM real-time imaging. Fresh plants were analysed for bioaccumulation and translocation factors of arsenic and silicon to justify the enhanced silicon uptake under proposed practice. Plant stress regulator enzymes viz. malondialdehyde (MDA), total protein, superoxide dismutase (SOD), guaiacol peroxidase (GPX) and ascorbate peroxidase (APX) from both conditions and found to be better in intermittent method over conventional practice with higher productivity.

The present study measured arsenic (As) concentrations in soil, groundwater and rice grain samples in two villages, Sarapur and Chinili, under Chakdaha block, Nadia district, West Bengal, India. This study also included a survey of the two villages to understand the knowledge among villagers about the As problem. Soil and groundwater samples were collected from fields in two villages while rice grain samples were collected from villagers’ houses. The results revealed the presence of As in higher concentrations than the maximum permissible limit of As in drinking water (10 µg L−1 and 50 µg L−1 by WHO and Indian standard, respectively) in groundwater [124.50 ± 1.11 µg L−1 (Sarapur) and 138.20 ± 1.34 µg L−1 (Chinili)]. The level of As in soil was found to range from 47.7 ± 0.14 to 49.3 ± 0.19 mg Kg−1 in Sarapur and from 57.5 ± 0.25 to 62.5 ± 0.44 mg Kg−1 in Chinili which are also higher than European Union maximum acceptable limit in agricultural soil (i.e. 20 mg Kg−1). The analysis of As in rice grains of five varieties, collected from residents of two villages, showed the presence of higher than recommended safe level of As in rice by FAO/WHO (0.2 mg Kg−1). The As concentration order was Gosai (0.95 ± 0.044 mg kg−1), Satabdi (0.79 ± 0.038 mg kg−1), Banskathi (0.60 ± 0.026 mg kg−1), Kunti (0.47 ± 0.018 mg kg−1) and Ranjit (0.29 ± 0.021 mg kg−1). Importantly, Gosai and Satabdi were the most popular varieties being consumed by local people. The data of consumption of rice per day in the survey was used for the measurement of average daily dose and hazard quotient. It was seen that the As hazard was negatively correlated to the age of residents. Therefore, children and toddlers were at higher risk of As exposure than elderly people. In addition, people with skin related As toxicity symptoms were also cited in the two villages. The study emphasized the severity of As problem in remote areas of West Bengal, India where people consume As tainted rice due to lack of awareness about the As problem and associated health issues.

Arsenic (As) is a ubiquitous environmental carcinogen that enters the human food chain mainly through rice grains. In the present study, we evaluated the potential of thiourea (TU; non-physiological reactive oxygen species scavenger) in mitigating the negative effects of arsenic (As) stress in indica rice variety IR64, with the overall aim to reduce grain As accumulation. At seedling stage, As + TU treatment induced the formation of more numerous and longer crown roots compared with As alone. The As accumulation in main root, crown root, lower leaf and upper leaf was significantly reduced to 0.1-, 0.14-, 0.16-, 0.14-fold, respectively in As + TU treated seedlings compared with those of As alone. This reduced As accumulation was also coincided with light-dependent suppression in the expression levels of aquaporins and photosynthesis-related genes in As + TU treated roots. In addition, the foliar-supplemented TU under As-stress maintained reducing redox conditions which decreased the rate of As accumulation in flag leaves and, eventually grain As by 0.53-fold compared with those of As treatment. The agronomic feasibility of TU was validated under naturally As contaminated sites of Nadia (West Bengal, India). The tiller numbers and crop productivity (kg seed/ha) of TU-sprayed plants were increased by 1.5- and 1.18-fold, respectively; while, grain As accumulation was reduced by 0.36-fold compared with those of water-sprayed control. Thus, this study established TU application as a sustainable solution for cultivating rice in As-contaminated field conditions.

The present study delineates the interactions of arsenic (As), a carcinogenic metalloid, and thiourea (TU), a non-physiological reactive oxygen species (ROS) scavenger, in rice plants grown in As contaminated fields in West Bengal, India. The study was performed for four consecutive seasons (two boro and two aman) in 2016 and 2017 with two local rice cultivars; Gosai and Satabdi (IET-4786) in a control and two As contaminated experimental fields. Thiourea (0.05% wt/vol) treatment was given in the form of seed priming and foliar spray. Thiourea significantly improved growth and yield of rice plants and reduced As concentration in root, shoot, husk and grains in both cultivars and fields. The reduction in As concentration ranged from 10.3% to 27.5% in four seasons in different fields. The average (four seasons) increase in yield was recorded about ~8.1% and ~11.5% in control, ~20.2% and ~18.6% in experimental field 1, and ~16.2% and ~24.1% in experimental field 2, for gosai and satabdi, respectively. Mean hazard quotient (HQ) and incremental lifetime cancer risk (ILCR) values of As reduced upon TU supplementation for both cultivars as compared to that of non-TU plants. Hence, TU can be effectively used to cultivate rice safely in As contaminated fields.

Arsenic (As) assessment in agricultural soils and corresponding crops is necessary from the global health safety perspective. To the best of our knowledge, we are reporting for the first time, As flux determining parametric equations for paddy field with seasonal rice cultivation under conventional flooding and dry-wet irrigation approaches. Rigorous field experiments and measuring quantitative parameters, flushed out or percolated into the deeper soil As flux was assessed. A wintery (boro)-monsoonal (aman) study from 2016 to 2019 has been conducted showing the efficiency of dry-wet irrigation on reduction of soil As bioavailability. The reduction in boro was 52.4% in 2016 to 64.8% in 2019 while in aman, it was 61% in 2016 to 74.9% in 2019. Low bioavailability was correlated to plant’s internal vascular structure that was found more rigid and firm in dry-wet field grown plants. Observed soil physico-chemical parameters clearly influenced As bioavailability as well as soil microbial community. Assessment of microbial diversity using metagenomics under altered water regime was done by population analysis, relative abundance, species richness, Krona chart comparison. Dry-wet field was found to be more diverse and enriched in microbial community than that of the flooded soil indicating an affective reduction of As bioavailability under biotic-abiotic factors.

With increasing anthropogenic activities, soil pollution by heavy metals and metalloids is causing serious quality issues in variable crops irrespective of irrigation pattern or seasonal impact. Rice, wheat, all kinds of lentils and leafy vegetables are contaminated with such metal(loid)s, and soil microbiota has been proven to be a vital biomanagement agent in remediation of such pollution. Rhizospheric bacteria, fungi, along with the mycorrhizal association, and algae are experimentally proven by many researchers over the years that these bioagents have the potential to mitigate metal toxicity at high level and can be applied at fields with proper implementation processes for alleviating the toxic metal(loid) stress on crops. This chapter has summarized the role of soil microbial communities in mitigation of soil metal(loid)s from being phyto-available and compromising crop’s quality.

The increasing industrialization and urbanization are also triggering environmental pollution, mostly unnoticed, in the case of soil pollution due to uncontrolled contamination by toxic elemental dispersion. The present study focused on this aspect and studied the clean-up of urban soil in a low-cost and eco-friendly way to restrict arsenic (As), lead (Pb) and mercury (Hg) contamination. Four potential ornamental plants, Catharanthus roseus (vinca), Cosmos bipinnatus (cosmos), Gomphrena globose (globosa) and Impatiens balsamina (balsamina) were used along with zero valent iron (ZVI) nanoparticles (Fe NPs) for remediation of the soil spiked with As (70 mg kg−1), Pb (600 mg kg−1) and Hg (15 mg kg−1) in a 60 d pot experiment. All plants were divided into four groups viz. control, spiked, spiked+20 mg kg−1 ZVI NP and spiked+50 mg kg−1 ZVI NP. FTIR and SEM were used for ZVI NP characterization. Soil and plant analyses and elemental assessments were done using ICP-MS, XRF and SEM. Among the four plants, cosmos showed the maximum accumulation of toxic elements (41.24 ± 0.022 mg kg−1 As, 139.15 ± 11.2 mg kg−1 Pb and 15.57 ± 0.27 mg kg−1 Hg) at 60 d. The application of ZVI NP at 20 mg kg−1 dosage was found to further augment plants’ potential for metal(loid)s accumulation without negatively hampering their growth. Cosmos were observed to reduce soil As from 81.35 ± 1.34 mg kg−1 to 28.16 ± 1.38 mg kg−1 (65.38%), Pb from 1132.47 ± 4.66 to 516.09 ± 3.15 mg kg−1 (54.42%) and Hg from 17.35 ± 0.88 to 6.65 ± 0.4 mg kg−1 (61.67%) at 60 d in spiked + 20 mg kg−1 ZVI NP treatment. Balsamina was the most sensitive plant and showed the least metal(loid)s accumulation. In conclusion, three of these plants are potent enough to use together for a better and enhanced removal of toxic elements from the contaminated soil with cosmos to be the best amongst these in urban areas.

Eichhornia crassipes (water hyacinth), imparts deficiency of soluble arsenic and other toxic metal (loid)s through rhizofiltration and phytoaccumulation. Without proper management strategy, this phytoremediation of metal (loid)s might fail and get reverted back to the environment, contaminating the nearby water bodies. This study, focused on bio-conversion of phytoremediating hyacinths, spiked with 100 times and greater arsenic, lead and cadmium concentrations than the average water contamination, ranging in 58.81 ± 0.394, 16.74 ± 0.367, 12.18 ± 0.153 mg Kg−1arsenic, 18.95 ± 0.212, 9.53 ± 0.054, 6.83 ± 0.306 mg kg−1 lead and 2.79 ± 0.033, 1.39 ± 0.025, 0.92 ± 0.045 mg kg−1 cadmium, respectively in root, shoot and leaves, proving it's phytoaccumulation capacity. Next, these hyacinths has been used as a source of organic supplement for preparing vermicompost using Eisenia fetida following analysis of total metal content and sequential extraction. Control soil was having 134.69 ± 2.47 mg kg−1 arsenic in compare to 44.6 ± 0.91 mg kg−1 at premature stage of compost to 23.9 ± 1.55 mg kg−1 at mature compost indicating sustainable fate of phytoremediated vermicompost. This vermiremediation of arsenic and other toxic elements, restricted the bioavailability of soil pollutants. Furthermore, processed compost amended as organic fertilizer, growing chickpea, coriander, tomato and chilli plant, resulted in negligible metal(loid)s in treated samples, enhancing also plant's growth and production.

With the ever-increasing demand for coal, the drawbacks associated with it also increase. Accelerating accumulation of fly ash, a byproduct in coal combustion processes, is of major environmental concern at present. Fly ash finds its maximum utilization in concrete and cement factory due to its pozzolanic property. However, fly ash is also used in the agricultural division as a “fertilizer” especially in West Bengal. However, there is no upper limit to how much fly ash should be added to agricultural soil. Current study deals with fly ash, that has been mixed with soil in four proportions namely, 0% (FA0), 25% (FA25), 50% (FA50) and 75% (FA75). A wetland emerged plant – Typha latifolia - has also been incorporated in the system. Mobility and metal(loids) relation has been established determining soil-ash physico-chemical properties along with nutritional enrichment to the plant system. Sequential Extraction methods are therefore employed to examine the element speciation. Application of 25 percent Fly ash was found to enhance the N(0.11%), P(0.09%), K(0.051%) and Si(7.7%) availability in soil and also resulted in better plant growth and xylem integrity as justified by electron microscopic observation. At end of final sampling, total arsenic concentration was 50.07 ± 0.25 mg Kg – 1 in Typha associated sample comparing to 59.51 ± 0.19 mg Kg - 1 in without Typha system using 25% ash. This study reflects the utility strategies of fly ash and Typha latifolia in combination for the better expunge of phyto-available metals form agricultural soil during a stop gap, before further crop production particularly another wetland plant, rice.

In the Bengal deltaic region, the shallow groundwater laced with arsenic is used for irrigation frequently and has elevated the soil arsenic in agricultural soil. However, the areas with seasonal flooding reduce arsenic in top layers of the soils. Study shows arsenic accumulation in the deeper soil layers with time in the contaminated agricultural soil (19.40±0.38mg/kg in 0-5cm, 27.17±0.44mg/kg in 5-10cm and 41.24±0.48mg/kg in 10-15cm) in 2013 whereas depletion in 2014 and its buildup in different parts of monsoon rice plant in Nadia, India. Principal Component Analysis and Cluster Analysis were performed, and Enrichment Factor was calculated to identify the sources of arsenic in the soil. Potential Ecological Risk was also calculated to estimate the extent of risk posed by arsenic in soil, along with the potential risk of dietary arsenic exposure. Remarkably, the concentration of arsenic detected in the rice grain showed average value of 1.4mg/kg in 2013 which has increased to 1.6 in 2014, both being above the permissible limit (1mg/kg). These results indicate that monsoon flooding enhances the infiltration of arsenic in the deeper soil layer, which lead to further contamination of shallow groundwater.

Rice plant cultivation around the world requires huge volume of fresh water, and depending on the soil constituents and enrichment profiling of elements present, uptake of metal(loid)s varies. Arsenic (As) predominates in its inorganic form in the soil system and gets altered in concentration of bioavailable fraction depending on various soil physico-chemical parameters and water application strategies used for rice cultivation. There is a proven correlation between different irrigation management processes and arsenic dissolution and mobility dynamics in soil system. Ferrous-manganese oxyhydroxides, phosphate, sulphur, silicate, and different soil organic matter (OM) compositions affect soil-As release from bound fractions in soil. Active microbial biomass, radial oxygen loss, and redox changes along with pH can potentially alter the plant available fraction of As in soil. With seasonal variation, irrigation practice applies several strategies of water management like continuously flooded, periodical irrigation, intermittent flooding, and sprinkler dripping and involves different field designs like permanent raised bed or occasional raised bed. As a way to nutrient-enriched rice cultivation, pisciculture in paddy field is also in practice. This chapter aims to discuss all the possible irrigation practices for rice cultivation alongside the soil environmental conditions that either triggers faster dissolution of As or hinders the mobility of being bioavailable.

Over the past three decades, the occurrence of high concentrations of arsenic (As) in drinking-water and its subsequent poisoning in rice has been recognized as a major public-health concern globally, especially in Ganga Delta Plain with more than 80 million peoples in serious As exposure far beyond than its allowable limit. An extensive field study was conducted for consecutive four years viz. 2013 to 2016, introducing a process of intermittent irrigation pattern comparing to the conventional practice of rice cultivation in India. The practice provides a combination of aerobic and anaerobic irrigation resulting better rice productivity with lesser arsenic mobility and accumulation in rice grains. This present research finding clearly points out to the marked reduction of arsenic load from average 1.6 mg/kg to 0.5 mg/kg in rice grain, much closer to FAO/WHO prescribed safe limit and in the continuous practice of proposed agricultural strategy resulting in a gradual decrease of 15% bioavailable arsenic in each year. Total productivity (in kg/hectare) also increased by 540 kg/year in boro and 340 kg/year in amon subsequently achieving the prescribed safe limit of As in grain.

This case study examines the policies formulated by the Indira Gandhi National Open University (IGNOU), an open and distance learning university of India for regulating the practices related to the assignments of its Bachelor of Education programme. Following the examination it argues that some policies are formulated in the context of the pedagogic significance of assignments in distance education and aim to support learning, while others seem to have been formulated for coping with the financial and administrative limitations imposed by the high enrolment in the programme. It infers that the dichotomy in the policy objectives reflects the diverging perspectives of the policies that have not been reconciled during policy formulation. It also suggests the way the policies that subordinate quality to quantity can be revised.

Tuberculosis, caused by the obligate intracellular pathogen Mycobacterium tuberculosis (Mtb), is responsible for 2–3 million deaths annually worldwide. Intracellular adaptability, which is critical for long-term persistence, requires the pathogen to neutralize host-mediated insults. The iron–sulphur (Fe–S) cofactor is essential for many enzymes critical for such ‘adaptation’. The Mtb genome harbors only one putative iron–sulphur cluster (ISC) operon (rv1460-66) predicted to be involved in the generation of the Fe–S cofactor. Except for rv1460, all other genes in this operon are anticipated to be essential. The current study investigated the role of rv1460, an sufR homologue of Mtb (sufRTB), in maintaining intracellular Fe homeostasis and its implications on mycobacterial pathogenesis. We found that Mtb ISC locus (rv1461–66) was transcribed as a single multigene transcript. We successfully generated the sufRTB null mutant strain (ΔsufRTB) of Mtb, suggesting nonessentiality of the gene under normal growth conditions. The mutant strain demonstrated enhanced biofilm generation and failed to grow under a low-Fe condition. Growth characterization studies indicated that SufRTB-mediated intracellular Fe homeostasis is essential for Mtb to persist in the host. Targeting mycobacterial persistence by inhibiting SufRTB protein activity may be a novel intervention strategy in tuberculosis treatment.

With ever-increasing arsenic (As) pollution in agricultural lands due to various and extensive anthropogenic activities, crop plants, rice to be particular, appeal for immediate attention with possible restriction mechanisms. Arsenic toxicity on rice plants also reveals simultaneous tolerance capacity of intracellular molecules that bind to arsenate/arsenite [As(V)/As(III)]. Interchange of As(III) and As(V) depends on the redox status of the rice field environment and that triggers the transportation competition between arsenate [AS(V)] to phosphate (PO43−) and arsenite [AS(III)] to water molecules as well as silica. Phyto-tolerance of As by rice plants is a dependent variable of As transport. Furthermore, studies suggest that inorganic forms of As are more mobile and toxic compared to organoarsenic compounds like monomethylarsonic acid (MMAA) and dimethylarsinic acid (DMAA). In response to As toxicity, various reactive oxygenic species (ROS) develop which in turn are subdued by the stress suppressor enzymes along with some specialized peptide molecules derived from glutathione (GSH), known as phytochelatins (PC). These protein molecules are well known to form PC-As complex that minimizes the toxicity by chelation. In addition, rice plant root cells are also equipped with Si transporter Lsi1 (OsNIP2;1) as well as aquaglyceroporin (AqpS) molecules that involve ATPase complex and effluxes out the As from the cellular matrix, sometimes transforming into volatile form engaging methylation cascade enzymes. Studies also reported, after analyzing rice genome, the presence of As tolerance gene regulating the quantitative trait locus (QTL) of phosphate uptake controller that suppresses As uptake and holds subsequent tolerance capacity in rice plant.

Nanoscience has caused revolutions in all spheres of the food industry, ranging from agricultural and livestock production to final tastes and nutritional values imparted to food, to the packaging of food products. With the rapid increase in the understanding of the human body and medicine, we are now able to understand much more clearly how our body interacts with the physical world. This enables us to design and engineer products to be introduced into the human body for various purposes, of which nutrition and drug delivery are the major areas. The applications include the following broad areas: agriculture and livestock rearing, food processing, food packaging, and nutritional supplementation. Under agriculture and livestock rearing, interesting topics, such as nanoparticle delivery of pesticides and insecticides, sustained release of growth hormones via differentially activating nanomaterial spheres, targeted drug and vaccine delivery, and site-specific genetic engineering by targeted use of DNA-filled nanocrystals, are found.

The potential of arsenic-resistant bacteria in association with Pteris vittata to reduce the level of arsenic from soil was studied. The physicochemical characteristics of contaminated paddy soil were analyzed, and 3 bacterial isolates amongst 11 were screened and were selected for further study. These three isolates were characterized by 16S rDNA sequencing and identified as Bacillus altitudinis Strain SS8 (KJ432582), Bacillus megaterium Strain SS9 (KJ432583) and Lysinibacillus sp. Strain SS11 (KJ432584). Of these, Lysinibacillus sp. Strain SS11 displayed arsenic tolerance of 3256 mg L−1 for arsenate and 1136 mg L−1 for arsenite. Additionally, it showed bioaccumulation capacity of 23.43 mg L−1 for arsenate and 5.65 mg L−1 for arsenite. It also showed resistance to other heavy metals, especially towards iron, copper and chromium. It was also observed that Pteris vittata was able to take up more arsenic and iron from soil in the presence of these bacterial strains than in their absence, leading to contamin...

Teacher education in India, including that offered by the open distance learning (ODL) system to thousands every year, imparts mainly pedagogic knowledge, although the need for integrated teacher education programmes has been underscored. As the Indira Gandhi National Open University (IGNOU), an ODL institution, will develop an integrated Bachelor of Education programme for secondary-level teachers, a model based on the Technological Pedagogical Content Knowledge (TPACK) framework has been proposed for developing and implementing it. The model takes cognisance of the systemic challenges to TPACK-based teacher education, but it does not envision radical changes in IGNOU’s teacher education framework for addressing these challenges. It includes propositions with theoretical underpinnings for redesigning the major components of the framework while retaining its basic structure. The model has been described in terms of its rationale, its structure and the way it envisages the progress of teacher trainees from...

Plastic in any form is a nuisance to the well-being of the environment. The ‘pestilence’ caused by it is mainly due to its non-degradable nature. With the industrial boom and the population explosion, the usage of plastic products has increased. A steady increase has been observed in the use of plastic products, and this has accelerated the pollution. Several attempts have been made to curb the problem at large by resorting to both chemical and biological methods. Chemical methods have only resulted in furthering the pollution by releasing toxic gases into the atmosphere; whereas; biological methods have been found to be eco-friendly however they are not cost effective. This paves the way for the current study where fungal isolates have been used to degrade polyethylene sheets (HDPE, LDPE). Two potential fungal strains, namely, Penicillium oxalicum NS4 (KU559906) and Penicillium chrysogenum NS10 (KU559907) had been isolated and identified to have plastic degrading abilities. Further, the growth medium for the strains was optimized with the help of RSM. The plastic sheets were subjected to treatment with microbial culture for 90 days. The extent of degradation was analyzed by, FE-SEM, AFM and FTIR. Morphological changes in the plastic sheet were determined.

Wazirpur industrial area of Delhi generates a huge quantity of sludge per day, which is highly acidic in nature (pH 2.7 to 4.4) and contains macronutrients, micronutrients as well as toxic metals. A pot-culture experiment was conducted by taking the two soils (JNU and Chhattarpur) amended with sludge (0%, 10%, 20%, 30%), pretreated with lime (0%, 0.5% and 1%). Two wheat seedlings were planted per pot containing 3 kg sludge amended or control soil and the experiment was carried out till harvesting (four months) in a glass house. Lime treatments enhanced the N content in wheat plant in almost all cases. Sludge and lime treatments enhanced dry weight in wheat plants grown in Chhattarpur soil and dry weight increased with time. Maximum growth was observed in 0.5 lime treated and 20% sludge amended soils. But we have to take an account about any kind of metal toxicity before disposal of this waste to land.

Indira Gandhi National Open University (IGNOU) of India uses multiple media and modes for reaching out to its distant learners. For most of the programmes offered to these learners, print is the master medium and other media supplement it. Instructions for the Bachelor in Education (B.Ed.), one of the popular programmes of IGNOU, are also delivered similarly. A survey was undertaken to determine the extent of utilization of instructions provided through various media by the students of B.Ed of two Indian metropolises –Delhi and Kolkata, having high penetration of advanced communication technologies. As the students of B.Ed. happen to be teachers who are supposed to be using ICT for teaching in their schools, the survey aimed to determine whether they were also using ICT for learning. The survey was carried out with a questionnaire with closed and open ended questions. It was found that only print medium was used for learning while the other media of the multimedia package remained mostly unused. The reason for this trend was found to be mainly the perception that the print medium is sufficient for assessment purposes. Suggestions have been made that to utilize the multiple media instructional system, interesting programmes that can hook learners be developed for delivery by electronic media and that gradually ICT may be integrated into the programmes from the present supplementary mode so that complacence in using it is reduced among learners.

A pot-culture experiment was conducted to observe the effects of acidic sludge addition to the soils on bioavailability and uptake of heavy metals in different parts of pea plant as well as its influence on the growth of that plant. It is observed from our result the abundances of total and bio-available heavy metals in sludge vary as follows: Fe > Mn > Cr > Ni > Cu > Pb > Zn > Cd and Fe > Ni > Mn > Cr > Cu > Zn > Pb > Cd. Sludge applications increased both the total metals, DTPA-extractable metals and total N in the soils. On the other hand lime application has decreased the bioavailability of heavy metals with no change in total N in sludge amended soils. Organic carbon showed positive correlation with all metals except Zn, Cr and Pb. CEC also showed a strong positive correlation ( R 2 > 0.7) with the low translocation efficiency of pea plants. The value of translocation factor from shoot to seed was found to be smaller than root to shoot of pea plants. Our study thus shows that pea plants were found to be well adapted to the soil amended with 10% sludge with 0.5% lime treatment, minimizing most of the all metal uptake in the shoot of that plant. So, on the basis of the present study, possible treatment may be recommended for the secure disposal of acidic electroplating sludge.

Typha angustata L. is a wetland plant commonly found in the marshy land or flood planes of the Ganges riverine system. A field study was taken on T. angustata L. to evaluate the uptake and transport of heavy metals (Mn, Cu, Zn, Cr, Ni and Pb) in different parts of plants grown on waste amended soils in water logged condition for 3 months. T. angustata L. accumulated Mn, Cu, Zn, Cr, Ni and Pb up to 119.21 ± 5.8 µg g− 1, 4.18 ± 0.5 µg g− 1, 5.72 ± 1.1 µg g− 1, 15.4 ± 1.9 µg g− 1, 5.3 ± 0.8 µg g− 1 and 7.21 ± 0.9 µg g− 1 in below ground organ (BL) respectively. Whereas, the maximum metal contents in above ground organ (AG) were 43.86 ± 3.2 µg g− 1, 1.73 ± 0.04 µg g− 1, 2.11 ± 0.07 µg g− 1, 6.31 ± 0.3 µg g− 1, 1.8 ± 0.04 µg g− 1 and 2.75 ± 0.03 µg g− 1 respectively. The plant also retained the tissue nitrogen up to 6.1 ± 0.38% in BL and 9.82 ± 0.54% in AG. It accumulated the maximum concentration of phosphorus 0.25 ± 0.02% in BL and 0.41 ± 0.02% in AG. Metals in both BL and AG were enriched with exposure, but the translocation factor was higher in BL in all amendments. Metal translocation factor was higher in BL/soil than AG/soil to a large extent. The translocation factor of metal from water to below ground organ was higher than water to above ground organ with a maximum value for Cr. There is a strong positive correlation of metal contents in plant tissue with soil organic matter (OM), and phosphorus contents in plant tissue. There is no significant correlation between metal uptake and nitrogen contents in plant tissue. This study reveals that T. angustata L. can be used for remediation of heavy metals containing waste when used in 25% waste amendment.

The concentrations of different forms of Zn, Cu, Mn, Ni, Cd, Cr, Pb and Fe metals were determined for the roadside sludge collected from pickling-rolling and electroplating industrial area. In sludge the relative abundance of total heavy metals were Fe>Mn>Cr>Ni>Cu>Pb>Zn>Cd and DTPA-extractable metals were in the order--Fe>Ni>Mn>Cr>Cu>Zn>Pb>Cd. Pot-culture experiment was conducted in soils amended with sludge (0%, 10%, 20%, 30%), pretreated with lime (0%, 0.5% and 1%). The soils were alkaline in nature (pH>8.3) with organic carbon contents were 0.34% and 0.72%. The most abundant total and bio-available metal was Fe. Two wheat seedlings were grown in each pot containing 3kg sludge-amended or control soil and the experiment was conducted till harvesting. Application of sludge increased both total and bio-available forms of metals in the soils, while lime application decreased the bioavailability of heavy metals in sludge-amended soils. The content of organic carbon showed positive correlation with all metals except Zn, Cr and Pb. CEC also showed a strong positive correlation (R2>0.7) with Fe, Mn, Cu, Ni and Cd. Though wheat plants are not accumulators, the translocation efficiency was appreciably high. The translocation factor from shoot to grain was found smaller than that of root to shoot of wheat plants. This makes an implication that the heavy metal accumulation was proportionally lesser in grain than in shoot. In, 10% sludge with 0.5% lime-amended soils; each of these toxic heavy metals was found to be within permissible range (USEPA). Hence, on the basis of present study, the best possible treatment may be recommended.

Nanotechnology has proven its competence in almost all possible fields we are aware of. However, today nanotechnology has evolved in true sense by contributing to a very large extent to the food industry. With the growing number of mouths to feed, production of food is not adequate. It has to be preserved in order to reach to the masses on a global scale. Nanotechnology made the idea a reality by increasing the shelf life of different kinds of food materials. It is not an entirely full-proof measure; however it has brought down the extent of wastage of food due to microbial infestation. Not only fresh food but also healthier food is being designed with the help of nano-delivery systems which act as a carrier for the food supplements. There are regulations to follow however as several of them pose serious threats to the wellbeing of the population. In coming days, newer modes of safeguarding food are going to be developed with the help of nanotechnology. In this paper, an overview has been given of the different methods of food processing, packaging, and preservation techniques and the role nanotechnology plays in the food processing, packaging, and preservation industry.

The study area comes in one of the eight districts of West Bengal where groundwater contains arsenic above the prescribed limit by WHO (10 μg/l). Each day groundwater is being withdrawn by the village people for the fulfillment of their basic needs and for agricultural purposes. With the groundwater along with high concentration of arsenic (As), many other heavy metals are also getting introduced in the environment. In the areas with a long history of use of such groundwater, the agricultural lands have been affected severely. The extent of contamination has increased to a level where the crops grown in those lands are becoming a major source for arsenic and other heavy metals poisoning and subsequently transfer to different trophic levels. Based on this concern a somewhat detailed study was carried out to obtain an idea about the magnitude of soil and water contamination in the area. The mean concentrations (mg/kg) of As (9.67), Fe (9275.58), Mn (190.04), Cu (26.53), and Zn (36.04) in the control land soils were found within the normal range. Whereas the mean As (54.40), Fe (15745.50), Mn (307.90), Cu (69.33), and Zn (44.56) were found to be in higher, mainly arsenic which is at an alarming point. In case of water samples, the pond water was having the mean concentration (μg/l) of As (32.63), Fe (57.21), Mn (30.25), Cu (0.82). Whereas in case of shallow groundwater there was more increase in the case of As (76.43), Fe (5493.22), Mn (253.63), and Cu (1.82). It was also observed that Zn although present in soil samples, it was below detection limits in case of water samples. The As concentration in soil and water showed a positive correlation. Also the correlation analyses between soil arsenic and other heavy metals shows a positive co-relation with all of them.

The recalcitrant nature of heavy metals and organic pollutants plays the key role in environmental degradation. Microalgae have emerged as one of the potential sink for removal of toxic and harmful substances from the surrounding. In recent years, there has been increasing interest in the use of biomass from microbial sources, particularly the microalgae, to absorb heavy metal ions as part of remediation efforts. They sequester, adsorb, or metabolize these noxious elements into substantial level. Algae require certain heavy metals for their normal functioning, these include iron for photosynthesis and chromium for metabolism. The use of algae has several advantages over bacteria based bioremediation as the process takes place under light conditions and does not need oxygen, instead, pollutants are taken up and digested, oxygen is added while carbon dioxide is removed. Microalgae in particular have been found to be suitable vectors for detoxification and have emerged as a potential low-cost alternative to physicochemical treatments.

Enzymes are the large biomolecules that are required for the numerous chemical interconversions that sustain life. They accelerate all the metabolic processes in the body and carry out a specific task. Enzymes are highly efficient, which can increase reaction rates by 100 million to 10 billion times faster than any normal chemical reaction. Due to development in recombinant technology and protein engineering, enzymes have evolved as an important molecule that has been widely used in different industrial and therapeutical purposes. Microbial enzymes are currently acquiring much attention with rapid development of enzyme technology. Microbial enzymes are preferred due to their economic feasibility, high yields, consistency, ease of product modification and optimization, regular supply due to absence of seasonal fluctuations, rapid growth of microbes on inexpensive media, stability, and greater catalytic activity. Microbial enzymes play a major role in the diagnosis, treatment, biochemical investigation, and monitoring of various dreaded diseases. Amylase and lipase are two very important enzymes that have been vastly studied and have great importance in different industries and therapeutic industry. In this review, an approach has been made to highlight the importance of different enzymes with special emphasis on amylase and lipase in the different industrial and medical fields.

A pot experiment was carried out to assess the effect of different amendments of industrial sludge on the growth of Canna indica L. as well as the translocation potential of heavy metals of this plant. The accumulation of metals (Cr, Fe, Cd, Cu, Ni, Zn, Mn and Pb) in different parts of C. indica L. grown on industrial sludge-amended soil increased with time and increasing doses of sludge amendments. Sequential extraction method was followed to estimate the different fractions of heavy metals in sludge-amended soils collected from different periods of this study. The results showed that Mn, Zn, Cd, Cr and Pb were mostly associated with Fe–Mn oxide fraction in all amendments, whereas, Ni was mostly found in residual (RES) fraction. Cu and Fe were found to be higher in organically bounded form (OM) and RES fraction. The metal concentration in C. indica L. after 90 days of experiment started, was in the order of Fe > Cr > Mn > Zn > Ni > Cu > Cd > Pb and the metal translocation was found lesser in shoot. With the increasing percentage of sludge amendments in soil the metal concentrations increased in different parts of plants. Overall, the plant C. indica L. was found to be well adapted in industrial sludge amendments and it may be recommended that this plant was found suitable for phytoremediation of most of the studied metals.