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Elucidation of Microbial Exopolysaccharide for Managing Environmental Contaminants
Published in Nitin Kumar Singh, Siddhartha Pandey, Himanshu Sharma, Sunkulp Goel, Green Innovation, Sustainable Development, and Circular Economy, 2020
Koushik Singha Roy, Soham Desai
The EPS is a complex heteropolymer containing the building blocks of glucose, arabinose, galactose, pentose, ribose, mannose etc. The complexity in the EPS structure depends on the branching structure of the monomers and the microbial sources from where these are extracted. The quantification process of the EPS is highly tedious. There are different sophisticated analytical techniques that ensure the rapid quantification of the EPS. Dubois et al. (1956) proposed the carbohydrate quantification method using phenol-sulfuric acid that indirectly offers quantification of EPS. The measurement of the carbohydrate concentration was refined by orcinol-sulfuric acid method (Bruckner, 1955) and resorcinol sulfuric acid method (Monsigny et al., 1988) also considered as the alternative way to quantify EPS. Moreover, the quantification of sugar concentration in EPS was also measured by researchers through the instrumentation technique of high-performance liquid chromatography (Baldev et al., 2015; Bhattacharyya et al., 2019). Ruiz-Matute et al. (2011) investigated EPS structure through the GC-MS (gas chromatography–mass spectrometry) technique. Chentir et al. (2017) studied the structural composition of EPS through FTIR spectra analysis (Fourier-transform infrared spectroscopy). A proper understanding of EPS structure is required in order to ascertain ecological roles and in bioremediation technology.
Organic Compounds in Raw and Finished Waters
Published in Samuel D. Faust, Osman M. Aly, Chemistry of Water Treatment, 2018
One of the first reports on formation of THMs in natural surface waters came from chlorination practices in the Rotterdam Waterworks.43 Gas-liquid chromatographic and mass spectrometric techniques were employed to identify CHCl3, CCl4, CHCl2Br, CHClBr2, and CHBr3 (Figure 2.2). The observation of these compounds led to two perplexing questions: (1) What is/are the precursor(s)? and (2) What is the source of the bromine? Considerable research has been conducted since the early 1970s to answer these questions. Early studies, 1974–1980, were summarized in the first edition of this tome that sought precursors yielding the above THMs.48 This early research looked at such model compounds as: acetone, polyhydric phenols, and natural organic color compounds (humic and fulvic acids) by Rook.43,49 For example, such degradation products of humic and fulvic acids as: resorcinol, phloroglucinol, pyrogallol, catechol, orcinol, 2,6- dihydroxytoluene, o- and m-phthalic acids, and 3,5-dihydroxybenzoic acids have been researched as precursors for THMs.50 On the basis of these compounds and proposed structures for humic and fulvic acids, “hydroxylated aromatic rings with two free meta-positioned OH groups are available active sites for haloform formation.”50
Thin-Layer Chromatography in Parasitology
Published in Bernard Fried, Joseph Sherma, Practical Thin-Layer Chromatography, 2017
Analysis of glycolipids in parasite material has been undertaken in the 1990s. A recent study analyzed glycolipids in chloroform–methanol(2:1) extracts of Schistosoma mansoni adults. The extract was centrifuged and the residue reextracted in chloroform–methanol (2:1). The supernatants were pooled and dried on a rotary evaporator. Glycolipids were separated as acetylated derivatives from other constituents by Florisil® column chromatography. The glycolipid fraction was then deacylated, and samples were applied on HPTLC plates and developed in chloroform–methanol–water (65:25:4).The glycolipids were visualized by spraying with orcinol reagent.55
Effect Of vacuum plasma on structure and function of fibers of Ichnocarpus frutescens
Published in Radiation Effects and Defects in Solids, 2021
Subrajeet Rout, Biswajit Mallick, Debabrata Dash, Nihar Ranjan Nayak, Chhatrapati Parida
In order to determine the percentage of total solid and moisture content, the IF fibers were incubated in a hot air oven (Labotech, India) at 105°C till the constant weight was achieved for analysis. The final oven dry weight (ODW) of the biomass was deducted from the initial weight of the biomass to get total solid in biomass (8). The glucan, xylan and lignin content were measured using the standard National Renewable Energy Laboratory (NREL) protocol. Primarily about 300 mg of biomass was digested with 72% H2SO4 at 30°C in a water bath (Osworld, India) for 60 min and secondary hydrolysis was carried out by using 4% H2SO4 at 121°C for 60 min in an autoclave (Osworld, India). To determine the amount of glucan and lignin, 4% hydrolysate was used and for the determination of hemicelluloses, 1% hydrolysate was used. To estimate the amount of glucan and hemicellulose, 1–2 mL of the respective hydrolysate was transferred to another micro centrifuge tube, CaCO3 was added to neutralize the pH to 6. These were then subjected to glucose and pentose sugar estimation. The glucan estimation was done using the glucose assay kit with the help of a microplate reader and pentose sugar estimation was done by using the Orcinol method. The total pentose sugar estimated was considered as the hemicellulose content of the biomass. The digested solid residues were filtered in a crucible with the help of a vacuum pump (Millipore, India) to estimate the acid-insoluble lignin (AIL) by burning the residues at 575°C in a muffle furnace (Labotech, India) for 4 h. A spectrophotometer (Eppendorff, India) was used to estimate the acid-soluble lignin (ASL) at 240 nm. The total lignin content of the biomass was estimated by adding the two lignin component (ASL and AIL) (9).
Bioethanol production from four abundant Indian agricultural wastes
Published in Biofuels, 2020
K. M. Harinikumar, R. L. Kudahettige-Nilsson, A. Devadas, M. Holmgren, A. Sellstedt
Samples were ground to powder using a ball mill (MM400, Retsch, Germany). Carbohydrate polymers were hydrolyzed using 72% sulfuric acid followed by an anthrone assay for the detection of released hexoses [28]. Pentose content was determined by orcinol assay [29] using the same hydrolysates. Total carbohydrate was calculated as a sum of hexose and pentose content.