Environmental Science And Technology - Research Publications
Permanent URI for this collectionhttps://kr.cup.edu.in/handle/32116/88
Browse
3 results
Search Results
Item Agricultural Wastes: A Feedstock for Citric Acid Production Through Microbial Pathway(CRC Press, 2023-06-02T00:00:00) Sachdeva, Saloni; Banu, Rajesh; Nandabalan, Yogalakshmi KadapakkamCitric acid holds a dominant position in industrial manufacturing due to its widespread application. It can be extricated as natural products through microbial pathways. A greater part of citric acid production is currently achieved by fermentation techniques where molasses/starch-based media are used. Microbial strains such as Penicillium spp, Aspergillus spp, Acremonium spp, and many others excrete variable amounts of citric acid as a primary metabolite. So far, Aspergillus niger has been recognized to produce a higher yield of around 112 g of citric acid /100 g of sucrose. However, the increasing demands has necessiated the need for more efficient procedures to enhance the yield. Several studies have been documented where agri-wastes such as rice straw, coconut husk, corn stalk, apple pomace, sugarcane bagasse, and many others were subjected to varied microorganisms (mainly fungal species) to increase the productivity of citric acid. Substantial citric acids have been produced using genetically modifying organisms (fungi Aspergillus and yeast Candida) and divergent combinations of microbe-substrate, but large-scale production has not yet been established. Also, the utilization of these fossil carbon sources has caused environmental deterioration, which instigates interest in agricultural waste as a potential substrate. Agricultural wastes are considered an economically feasible option and a renewable source that can be consumed by plenty of microorganisms. This chapter covers a detailed description of agri-waste bioconversion to citric acid which can further help in this fast-moving domain. � 2023 selection and editorial matter Gustavo Molina, Minaxi Sharma, Vipin Chandra Kalia, Franciele Maria Pelissari, Vijai Kumar Gupta, individual chapters, the contributors.Item Meta-analysis of uranium contamination in groundwater of the alluvial plains of Punjab, northwest India: Status, health risk, and hydrogeochemical processes(Elsevier B.V., 2021-11-23T00:00:00) Sahoo, Prafulla Kumar; Virk, Hardev Singh; Powell, Mike A.; Kumar, Ravishankar; Pattanaik, Jitendra Kumar; Salom�o, Gabriel Negreiros; Mittal, Sunil; Chouhan, Lokesh; Nandabalan, Yogalakshmi Kadapakkam; Tiwari, Raghavendra PrasadDespite numerous studies, there are many knowledge gaps in our understanding of uranium (U) contamination in the alluvial aquifers of Punjab, India. In this study, a large hydrogeochemical dataset was compiled to better understand the major factors controlling the mobility and enrichment of uranium (U) in this groundwater system. The results showed that shallow groundwaters (<60 m) are more contaminated with U than from deeper depths (>60 m). This effect was predominant in the Southwest districts of the Malwa, facing significant risk due to chemical toxicity of U. Groundwaters are mostly oxidizing and alkaline (median pH: 7.25 to 7.33) in nature. Spearman correlation analysis showed that U concentrations are more closely related to total dissolved solids (TDS), salinity, Na, K, HCO3?, NO3? Cl?, and F? in shallow water than deep water, but TDS and salinity remained highly correlated (U-TDS: ? = 0.5 to 0.6; U-salinity: ? = 0.5). This correlation suggests that the salt effect due to high competition between ions is the principal cause of U mobilization. This effect is evident when the U level increased with increasing mixed water species (Na-Cl, Mg-Cl, and Na-HCO3). Speciation data showed that the most dominant U species are Ca2UO2(CO3)2? and CaUO2(CO3)3?, which are responsible for the U mobility. Based on the field parameters, TDS along with pH and oxidation-reduction potential (ORP) were better fitted to U concentration above the WHO guideline value (30 ?g.L?1), thus this combination could be used as a quick indicator of U contamination. The strong positive correlation of U with F? (? = 0.5) in shallow waters indicates that their primary source is geogenic, while anthropogenic factors such as canal irrigation, groundwater table decline, and use of agrochemicals (mainly nitrate fertilizers) as well as climate-related factors i.e., high evaporation under arid/semi-arid climatic conditions, which result in higher redox and TDS/salinity levels, may greatly affect enrichment of U. The geochemical rationale of this study will provide Science-based-policy implications for U health risk assessment in this region and further extrapolate these findings to other arid/semi-arid areas worldwide. � 2021 Elsevier B.V.Item Multi-parametric groundwater quality and human health risk assessment vis-�-vis hydrogeochemical process in an Agri-intensive region of Indus basin, Punjab, India(Taylor and Francis Ltd., 2021-06-14T00:00:00) Jaswal, Vijay; Kumar, Ravishankar; Sahoo, Prafulla Kumar; Mittal, Sunil; Kumar, Ajay; Sahoo, Sunil Kumar; Nandabalan, Yogalakshmi KadapakkamThe groundwater quality of the Indus basin of Punjab, India, is a serious concern due to the existence of toxic contaminants. Although, this contamination has been documented in some studies, some part of this basin is scantily explored. This is true for the Fazilka district of Malwa region, Punjab. In the present study, a total of 78 groundwater samples were collected from this district to evaluate their suitability for drinking and irrigation purpose, to understand the current hydrogeochemical processes involved and assess the human health risk status of the region. The results of the water quality index (WQI) revealed that majority of the groundwater samples were of poor quality with U, F?, SO42?, and NO3? exceeding the BIS limit in 60%, 94%, 43%, and 19% of samples, respectively. The groundwater geochemistry is mainly influenced by rock-water interaction. Ca-Mg-Cl water type is identified as the dominant hydrogeochemical facies, followed by Ca-Mg-SO42? and Na-Cl types. The Mg2+ and Na+ were identified as the major cations, while SO42? and HCO3? existed as the dominant anions. Furthermore, the results of Principal Component Analysis (PCA), Hierarchical cluster and Pearson correlation matrix (PCM) analyses corroborated the elevated level of U, F?, SO42? with geogenic activity supplemented with agrochemical activities. The annual effective intake dose of U exceeded the WHO recommended mean annual effective dose of U (100 �Sv y?1) for all age groups with infants recording the highest dose of U (151 �Sv y?1). Moreover, the non-cancer risk of U and F? exceeded the USEPA limit (HQ-1) in majority of the sites. The high cumulative risk of non-carcinogenic contaminants (HI-4.6) in the entire study area is a matter of grave concern. � 2021 Informa UK Limited, trading as Taylor & Francis Group.