School Of Environment And Earth Sciences
Permanent URI for this communityhttps://kr.cup.edu.in/handle/32116/83
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Item Changes in the surface water quality of a tropical watershed in the southeastern amazon due to the environmental impacts of artisanal mining(Elsevier Ltd, 2023-04-12T00:00:00) Salom�o, Gabriel Negreiros; Dall'Agnol, Roberto; Sahoo, Prafulla Kumar; Almeida, Gabriel Soares de; Amarante, Rafael Tarantino; Zeferino, Leiliane Bozzi; Lopes, Jo�o Paulo Nobre; Souza Filho, Pedro Walfir Martins e; Costa, Normara Yane Mar da; Guimar�es, Jos� Tasso Felix; Silva, Marcio Sousa da; Martins, Gabriel Caixeta; Teixeira, Mayara Fraeda Barbosa; Marques, Eduardo Duarte; Ang�lica, R�mulo Sim�es; Ara�jo, Wilker Emmanoel OliveiraThe expansion of areas of human occupation and the increase in economic activity and deforestation are negatively impacting the Amazon ecosystem. Situated in the Caraj�s Mineral Province in the southeastern Amazon, the Itacai�nas River Watershed (IRW) encompasses several active mines and has a historical record of intense deforestation primarily linked with the expansion of pasturelands, but also of urban areas, and mining activities. Industrial mining projects are subjected to strict environmental control, but artisanal mining (ASM; �garimpos�) sites have not been controlled, despite their known environmental impacts. In recent years, the opening and expansion of ASM in the IRW for the exploitation of mineral resources (Au, Mn, and Cu) have been remarkable. This study presents evidence of anthropogenic impacts, mainly caused by ASM, on the quality and hydrogeochemical characteristics of the IRW surface water. The hydrogeochemical data sets of two projects carried out in the IRW, during 2017 and from 2020 until present, were used to evaluate these impacts within the region. Water quality indices were calculated for the surface water samples. For the whole IRW, water collected during the dry season tended to yield better quality indicators in comparison to those collected during the rainy season. Two sampling sites at Sereno Creek showed very poor water quality and extremely high concentrations of Fe, Al, and potentially toxic elements over time. From 2016 to 2022, ASM sites increased markedly. Moreover, there are indications that Mn exploitation via ASM in Sereno hill is the main source of contamination in the area. New trends of ASM expansion were observed along the main watercourses, related to the exploitation of Au from alluvial deposits. Similar anthropogenic impacts are registered in other regions of the Amazon and environmental monitoring should be encouraged to assess the chemical safety of strategic areas. � 2023 Elsevier LtdItem Evaluation of mycelial nutrients, bioactive compounds, and antioxidants of five Himalayan entomopathogenic ascomyceteous fungi from India(Begell House Inc., 2015) Sharma, S.K.; Gautam, N.; Atri, N.S.In this study, using standard methods, mycelial nutrients, bioactive compounds, and antioxidants were analyzed for the first time for five fungal species: Isaria sinclairii (Berk.) Lloyd, I. tenuipes Peck, I. japonica Yasuda, I. farinosa (Holmsk) Fr. and Cordyceps tuberculata (Lebert) Maire. All of these species were low in fat content and rich in protein, fiber, ash, and carbohydrates. Mineral elements (Fe, Mg, Cu, Mn, and Ca) were detected in appreciable amounts. All three types of fatty acids (saturated, monounsaturated, and polyunsaturated) as well as bioactive compounds (ascorbic acid, ?-carotene, lycopene, phenolic compounds, and polysaccharides) were detected for each species. The investigated species showed high ferric-reducing antioxidant power as well as 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity. Although differences were observed in the values of each species, each species showed richness in one or more components. ? 2015 Begell House, Inc.Item Chemical composition and antioxidant and antibacterial activities of cultured mycelia of four clavicipitaceous mushrooms (Ascomycetes) from the Indian Himalayas(Begell House Inc., 2017) Sharma, S.K.; Gautam, N.Cultured mycelia of 4 clavicipitaceous fungi belonging to 2 genera, Cordyceps (C. gracilis, C. cicadae, C. sinclairii) and Metacordyceps (M. dhauladharensis), were analyzed for their chemical composition and antioxidant and antibacterial activities. Experiments to determine these characteristics were performed following standard methods. The fatty acid profiles of mycelia of all the species were analysed using gas chromatography. Chemical composition analysis of mycelial samples revealed carbohydrates (46.72 ? 0.7% to 63.40 ? 0.3%), protein (14.19 ? 0.2% to 26.16 ? 0.1%), crude fibers (0.93 ? 0.0% to 1.22 ? 0.0%), and ash (0.77 ? 0.0% to 0.98 ? 0.0%). The amounts of calcium and iron in mycelia were significantly higher than amounts of magnesium, copper, and manganese. The amount of ?-carotene ranged from 0.67 to 1.17 ?g/100 g; lycopene, from 0.30 to 0.57 ?g/100 g; phenolic compounds, from 29.16 to 43.12 mg/100 g; polysaccharides, from 104 to 126 mg/g; and flavonoids, from 2.15 to 4.25 mg/g. All tested species showed significant (P ? 0.05) antioxidant activities measured based on half-maximal effective concentrations. C. cicadae possessed the lowest half-maximal effective concentration compared with the other species. All 4 species showed a broad spectrum of antibacterial activity against 7 tested pathogenic bacterial strains. ? 2017 Begell House, Inc.